Solution Spot | Carboline

Tue, 26 Mar 2024 09:41:17 -0400

Douglas Channel in British Columbia, Canada, is no stranger to big ships.

The fjord connects the Pacific Ocean to the deep-sea terminal at Kitimat, a name borrowed from the indigenous Haisla First Nation, where Alcan and then Rio Tinto have operated an aluminum smelter since the 1950s.

Bauxite comes in, smelted aluminum comes out. But soon, more big ships will ply these waters.

That’s because a joint venture led by Royal Dutch Shell is building Canada’s largest liquefied natural gas (LNG) export terminal here. Another joint venture—Texas-based Fluor and the Japanese engineering firm JGC Corporation—is the project’s engineering, procurement, and construction (EPC) contractor.

Instrumental to that project has been the application of a massive amount of passive fire protection (PFP) material that will protect the facility’s staff and infrastructure once it opens in 2025.

Foundational to successful operation

The process of building LNG Canada’s Kitimat facility has been complex and involves impressive global logistics.

The plant consists of modules which were fabricated at a Fluor shop in Zhuhai, China. Following fabrication, cargo ships hauled the modules across the Pacific and up Douglas Channel to the port at Kitimat. From there, the modules were strapped to special flatbed trailers for the slow, careful journey to the job site a mile up the road.

Over 200 of these modules comprise the sprawling facility. They rest on steel piles driven into the earth, which is too soft here—and too seismically active—for a conventional slab foundation. Steel support stools bolted to the tops of the piles anchor the modules in place.

Because these stools bear structural loads, code requires that they be fireproofed.

Pyrocrete 341 simplifies hazard planning inside battery limits

Fire protection requirements are not one-size-fits-all. They typically vary across areas of a facility depending on the processes located there and the fire risks that attend them.

Oil & gas and other processing facilities are organized according to battery limits, where anything which is directly related to the primary facility process is inside battery limits (ISBL) and anything related to a secondary, indirect function is outside battery limits (OSBL).

These boundaries are meant to clearly organize responsibility over separate areas, but they also provide a convenient way to specify fire protection. In the case the LNG Canada plant at Kitimat, structures located OSBL where fireproofing is required must have one-hour fire protection. Structures ISBL—including the steel support stools—require two hours.

The operative Shell specification dictated that Carboline’s Pyrocrete 241 be applied to the steel support stools.

A mainstay in the oil & gas industry since its launch in the late 1970s, Pyrocrete 241 offered excellent protection in both cellulosic and hydrocarbon thermal scenarios. The Portland-cement based material offered better thermal performance than concrete at one-third the installed weight. It became the industry’s version of a household name.

But Carboline representatives suggested instead that Pyrocrete 341 be applied to the steel stool supports at Kitimat instead of its predecessor.

Pyrocrete 341, launched in 2020, is a next-generation, Portland-cement based fire resistive material tested to meet the following criteria:

• UL 1709 hydrocarbon fire up to four hours
• ISO 22899-1 hydrocarbon jet fire from 30 minutes to four hours
• ISO 20088-1 cryogenic spill protection to -319°F (-195°C)
• ISO 20088-1 cryogenic spill followed by ISO 22899-1 hydrocarbon jet fire
• NFPA 290 simultaneous torch and hose stream-resistant (extended to 150 minutes)
• 4-bar overpressure blast resistance
• 4-bar overpressure blast resistance followed by hydrocarbon fire

Aware that LNG plants deal with a commodity held at cryogenic temperatures, we believed that Pyrocrete 341’s more comprehensive protective features would simplify LNG Canada’s fire protection regimen. One product covered all the bases.

Additionally, Pyrocrete 341 is easy to apply, which made a big difference given the scope of fireproofing application: First, crews would wrap the stools in a steel mesh to give the material something to cling to as it cured. Then, they would build forms around the mesh-wrapped stools. Finally, they would trowel the material onto the mesh and within the forms, stool by stool, of which there are more than 3,000. The time saved would add up.

Persuaded that Pyrocrete 341 was the better fit for this facility’s specific needs, the project EPC agreed to our proposed change.

A new chapter in Canada's energy saga

Depending on whose statistics you cite, Canada is either the fifth or sixth-largest energy producer in the world.

Could the Kitimat facility help it earn a spot higher on that list? Indeed, demand for Canadian energy exports has increased in recent years, and the very existence of this new facility demonstrates that industry players expect that to remain the case long-term.

But when the LNG Canada facility opens in 2025, it will mark a new chapter. Most of the LNG it produces there will go to Asia or points beyond, and not to the U.S., which previously has been the destination for around 90% of the energy Canada extracts for export.

Diversifying exports is a good thing. It means smoother sailing for the Canadian economy.

A rising tide lifts all ships, including those big ones in Douglas Channel.

Solution Spot | Carboline

Wed, 20 Mar 2024 11:58:32 -0400

How do you judge whether a corrosion protection system is “good?”

Manufacturers pre-judge their products as good all the time.

But talk is cheap, and even a strong score from the lab will never be as convincing as field performance.

Here, we discuss two bridge coating projects where the same “ordinary” corrosion protection system was specified. And while in many ways the projects were similar, they couldn’t have been more different in terms of their context.

One of these bridges, you’ve probably never heard of. The other, nearly everyone has.

Photo courtesy of Famartin.

Point-No-Point Bridge, New Jersey

Even if locals around Newark or Hoboken do know about this plain steel swing-type railroad bridge crossing the Passaic River, they probably don’t know how it got such a strange name.

We don’t, either. We tried.

Owned by Conrail and serving CSX freight trains, Point-No-Point is one of many swing bridges common to this area. The Passaic is still navigable at this location 2.6 miles in from Newark Bay, so when barges need to pass, Point-No-Point swings open.

It’s worked this way since the bridge was built in 1901.

It could work better, though.

The distance between Point-No-Point’s piers restricts the size of vessels traveling past them. Bigger boats could go farther upriver if not for this limitation. Another limitation is the time it takes to open and close the bridge: Five hours each way. Scheduling freight trains would be much easier on CSX if a passing boat didn’t trigger a 10-hour outage of their tracks.

So at the end of 2022, a long-awaited replacement project began. The feet of the new swing bridge will stand wider apart, allowing bigger vessels to reach customers farther upriver. It will take just five minutes to open or close the span.

A marked improvement, but this is an ordinary modern swing bridge. Its design is familiar to anyone who’s seen a railroad overpass before, and it does what its predecessor did for over 120 years.

The three-coat zinc-epoxy-urethane system specified to protect the bridge’s steel is also familiar to anyone in the coatings industry.

Carbozinc 11 HS is an ultra-low VOC inorganic zinc primer with very high zinc loadings ideal for environments where salting is expected. Being a railroad bridge, road salt is not a concern, but the Passaic River at this location is brackish at times owing to tides.

Carboguard 893 is a high-solids epoxy commonly specified as an intermediate over zinc-rich primers and suitable beneath a wide range of urethane topcoats. It offers very good corrosion protection and meets current AIM VOC criteria.

Carbothane 133 LV is a high-solids, high-build urethane topcoat with exceptional weathering characteristics. In addition to strong performance, its low VOC and HAPs content are critical for specification in areas with stricter environmental regulations such as the northeast U.S.

These products together are considered a standard coating system, but do not interpret “standard” to mean “average.” Rather, this system has set the standard—and sets it again and again with incremental improvements toward higher solids and lower VOC content.

That’s why it’s so familiar. It’s worked so well for so long.

No mystery, then, why that same system was essential to the rapid reopening of one of the busiest stretches of highway in the country.

I-95 bridge replacement, Philadelphia

The bridge carrying I-95 over Cottman Avenue in northeast Philadelphia was as ordinary as overpasses get. But an extraordinary crash on the morning of June 11, 2023, brought the bridge down—and news cameras brought everyone the story.

A tanker truck laden with 8,500 gallons of gasoline lost control on the off-ramp, overturned, and exploded beneath the highway. Heat from the fire was so intense that steel support girders melted, and part of the highway collapsed eight minutes before the first firefighters even arrived.

I-95 runs from Miami to the Canadian border, and is one of the busiest roads in the U.S. The bridge over Cottman Avenue in Philadelphia served 160,000 or so vehicles each day. There was no doubt the bridge would be replaced, but the question was just how quickly.

A temporary solution opened to traffic just 12 days later—a miraculous feat—but executing the permanent solution was similarly stunning. The new overpass was built in just 30 days.

Most of that heroic work had nothing to do with us. But we will take credit for the protective coating system applied to the bridge’s steel members. It was the same one as at Point-No-Point, just an hour’s drive up the highway. Once again, everyone involved in the project was quite familiar with the system.

Here's why that familiarity made a difference:

• The Pennsylvania Department of Transportation approved the system in no time because it is NEPCOAT-approved and well-known to their engineers
• The steel fabricator knows the system very well and its shop painters executed the work flawlessly
• This being such a common bridge corrosion protection system, we had plenty of product already in stock for rapid delivery to the fabricator

In praise of ordinary

Specifiers and painters today probably regard Carboline’s Carbozinc 11 + Carboguard 893 + Carbothane 133 system as a completely ordinary system to achieve 30 years of maintenance-free bridge steel protection.

No need to dress it up any more than that. Because calling it ordinary is to pay us a high compliment. We’d put that on one of those billboards you might pass on I-95.

The billboard would read: “Ordinary system. Extraordinary peace of mind.”

Solution Spot | Carboline

Thu, 07 Mar 2024 14:46:37 -0500

Habitable spaces today are constructed with more synthetic materials than in the past. And into these spaces we cram all manner of battery-powered devices that burn very hot and release toxic smoke.

In part 1 of this series, we wondered if it’s time to debate the adequacy of the cellulosic fire test standards we use to evaluate a material’s thermal response.

And in our view, the answer is yes.

In fact, recent history is rife with near misses and tragic events that, as we argue below, have already settled the debate.

Luton, United Kingdom

An accidental ignition inside a vehicle parked at London Luton Airport Terminal Car Park 2 on Oct. 10, 2023, led to the catastrophic fire during which part of the multi-level structure collapsed.

The incident is recent enough at this writing in February 2024 that formal findings remain pending. But a principal criticism that emerged in the immediate aftermath was that Terminal Car Park 2 had no fire suppression sprinklers.

The frenzied claim on social media that an electric vehicle (EV) was the source of the fire was false.

But even though an EV battery thermal runaway did not cause the event, EVs were parked inside the structure, and some fueled the blaze. Law firm Browne Jacobson noted that it takes more than twice the amount of water to douse an EV battery fire compared to a traditional vehicle fire.

In fact, firefighters ordinarily elect not to fight battery fires at all because it’s safer for everyone. They only initiate a firefight to contain some more catastrophic risk.

EV market penetration will only grow. There will never be fewer of them in parking structures than there are right now.

Fortunately, no one died in the fire, although some firefighters and an airport employee suffered smoke inhalation. But the cost of the Luton disaster will still be mighty, mostly to insurers. The Bedfordshire Fire & Rescue Service Fire said in late 2023 it’s unlikely that any of the 1,405 cars they knew to be in the car park at the time of the fire would be usable after what remains of the car park is demolished.

Stavanger, Norway

Much more is known about the fire, first response, and aftermath of the Jan. 7, 2020 car park fire at Stavanger Airport Parking Building 3.

The fire resulted in a partial collapse of the multi-level parking structure and the destruction of hundreds of vehicles.

A RISE Fire Research report establishes key facts which are crucial to any discussion of modern fire loads and the adequacy of legacy material response test methods.

One is that there were no fire suppression sprinklers, same as Luton.

Another is that the fire originated in a parked car in an upper level, a location which fire service personnel reported was difficult to access with their large apparatus. The report also indicated firefighters initially had difficulty locating fire hydrants, delaying their firefight.

Next, the portion of the parking structure that collapsed was a newer build, utilizing different materials not considered in older fire safety designs which were repurposed for its construction. Newer designs existed but their changes compared to older designs were not adequately emphasized, according to the report.

Also noteworthy is the fire development timeline. For the first 15 or so minutes from ignition, the fire was apparently contained to a single vehicle. But then, witnesses reported hearing a “bang” from an electric vehicle parked near the burning car (the EV, to be clear, was not the cause of the fire). Just a minute after the bang, witnesses observed flames, heard more bangs, and saw several more cars on fire.

After only 18 minutes and 17 seconds, 10 cars were burning. The first fire trucks were not deployed until 19 minutes after ignition. Crews fought the fire for little more than an hour before evacuating ahead of the structure’s imminent collapse.

No fire service response can be instantaneous or perfect. But keep Stavanger in mind as you consider that structural steel loses half its load-bearing integrity once it reaches 1,000°F (538°C), and that an EV battery can reach 1,832°F (1,000°C) in as little as five seconds in a thermal runaway event.

As EVs proliferate, it is urgent that stakeholders scrutinize trends in construction materials, the performance of passive fire protection (PFP) products, and operative thermal response test methods—and to say so frankly if these all fall short against modern fire loads.

Liverpool, United Kingdom

The fire that destroyed the King’s Dock car park in Liverpool on New Year’s Eve 2017 also began in a parked combustion-engine car. The Merseyside Fire & Rescue Service protection report published in the aftermath details the convergence of factors that made this as bad as it was.

For one example, the Service’s evidence strongly refuted a decades-old assertion that fires in multi-story, reinforced concrete parking structures tend not to spread from floor to floor. In the early stage of the King’s Dock fire, intense heat melted plastic and aluminum drainage infrastructure above the burning vehicle which provided a vector for its spread to the floor above.

Another serious hazard was plastic petrol tanks in most of the parked cars. Investigators reported that as tank after tank failed, an intense running fuel fire developed.

Further, there was clear evidence of widespread heat-induced failure of the structure’s concrete floor slabs which aided the spread of the fire from level to level.

It could have been far worse. The King’s Dock car park was adjacent to the Arena Convention Center of Liverpool, where the Liverpool International Horse Show was in progress at the time of the fire. Thousands of spectators were safely evacuated. Also evacuated were the residents of two apartment buildings erected just beside the car park.

Firefighters noted that the location of these residential structures prevented them from deploying aerial firefighting appliances in ideal positions. Fortunately, those apartment buildings and their occupants survived the fire. Minor injuries were reported, most of them smoke inhalation.

Jecheon, South Korea

Bad as they are, the disasters described above do not represent the worst-case scenario.

But the fire that destroyed the multi-story Jecheon Sports Center in the small town of Jecheon, South Korea, does.

Twenty-nine people died and dozens more were injured on Dec. 17, 2017, after a fire that started in the ceiling above a partially enclosed ground-floor parking area spread quickly upward.

According to the investigation following the fire, a faulty electrical wire installed to prevent piping from freezing sparked the blaze which spread rapidly once it encountered insulation in the ceiling of the parking area.

This small town’s firefighters were completely overwhelmed, the most agonizing example being their choice to try preventing the explosion of a nearby propane storage tank instead of entering the building to attempt immediate rescues. They did not have enough people or equipment to do both at once.

That the Jecheon Sports Center did not collapse only demonstrates that a structural failure is not a prerequisite for tragedy. Thick plumes of toxic smoke and an under-equipped, under-staffed fire service were the culprits here.

Coming in part 3: What change looks like

The events narrated above do not constitute anything like an exhaustive list. The more we looked, the more examples we found.

Nor does our selection of the events suggest that EVs are bad or that we should be afraid of parking structures.

But these examples are instructive in demonstrating the many and complex hazards that modern fire loads pose in today’s built environment:

First, EVs and even larger, grid-scale energy storage systems will proliferate. Thermal runaways did not cause these fires, but it is still true that EVs and other energy storage assets release more heat, release it more quickly, and create more toxic byproducts when they burn versus conventional materials.

Second, the construction of mixed-use spaces favoring higher density will continue accelerating. So will the use of synthetic building materials and furnishings, which feature higher calorific potentials than the traditional materials on which today’s thermal response testing methods are based.

Third, parking structures are an exceptionally difficult venue for firefighters because they often impede access and cause decisive action to be delayed. When these structures are incorporated within a mixed-use envelope, the difficulties and risks each compound.

Our objective in part 1 of this series was to suggest that, owing to modern fire loads, the adequacy of cellulosic fire test standards in use today to evaluate materials’ fire resistive properties should be up for debate.

The objective here was to argue that what happened in Luton, Stavanger, Liverpool, and Jecheon demonstrate that this debate is already settled.

In the final installment of this series, we’ll explore the quandary of modern fire loads against obsolete material response evaluation methods from the lens of the myriad stakeholders—insurers, architects, engineers, builders, and others—who will bear the high and growing cost that will accrue until that gap is closed.

And, we’ll suggest alternative material response evaluation methods that might be better suited to a present and future of hotter, more dangerous fires.

Solution Spot | Carboline

Tue, 13 Feb 2024 13:47:21 -0500

When the astronauts of NASA's Artemis III space mission launch in 2026, the world will stand still and watch as one of humanity's great stories is written in real time.

The first crewed lunar landing since Apollo 17 in 1972 will also be the end of an era: It will be the last time astronauts leave Earth in the Block 1 Space Launch System (SLS).

Photo courtesy of NASA

Bigger and more powerful Block 1B and Block 2 SLSs will carry missions starting with Artemis IV. That mission marks the beginning of construction of "Gateway," the first deep-space outpost of its kind. Before its crew lands on the moon some time in 2028, they will put the first module of the new space station into lunar orbit.

But before that project begins, crews must complete a construction project underway right now in 2024. That's why we're watching the fabrication, assembly, and protective coating of NASA's ML-2 launcher so closely.

We’ve been here before.

Unbeatable corrosion protection from Carbozinc 11 and Armorlast I

In layman's terms, the ML-2 launcher is the big tower that supports the rocket and its payload during assembly, preparation, transit to the launch pad, and liftoff. Once complete, it will stand 377 feet tall and weigh 12.9 million pounds.

NASA is spending big to build ML-2, so they chose a resinous coating system they know from past experience will protect their investment against corrosion in this humid coastal region.

Carbozinc 11 HS is an ultra-low VOC variant of the same inorganic zinc-rich primer technology that has protected structural steel in the VAB since 1966. It imparts excellent galvanic protection in the humid coastal environment to which it is exposed, and also features low-temperature curing down to 15°F (-9°C).

That's followed by Armorlast I, an inorganic finish coat that further enhances corrosion protection. Its inorganic composition imparts superior weatherability and good resistance to high temperatures.

A secondary and often overlooked benefit of inorganic systems is that, though they do eventually break down, the byproducts of their degradation consist of inert particles rather than microplastics.

The Carbozinc and Armorlast system represents most of the volume of paint required for this project, but other Carboline products in a wide range of colors also were specified for logos, insignias, safety markings, and other needs:

• Carboguard 893 epoxy primer and intermediate coat offers excellent corrosion protection, good abrasion resistance, and complies with current AIM VOC regulations.
• Carbomastic 15 aluminum-pigmented epoxy mastic has a long history of excellent barrier protection, including over minimally prepared surfaces.
• Carbothane 133 LH polyurethane finish features outstanding performance in aggressive environments with very low HAPs content.
• Carbothane 134 HG polyurethane finish has high-gloss characteristics and exceptional weathering, corrosion, abrasion, and chemical resistance.
• Carboxane 2000 siloxane finish is applied over a compatible primer and provides exceptional weathering and outstanding color and gloss retention. It completes a two-coat system that meets or exceeds the performance of a traditional three-coat system.
• Carbocrylic 3359 MC single-component water-based acrylic is a versatile interior/exterior coating with excellent color and gloss retention.

Comparing inorganic zinc coatings against galvanizing and metallizing

Painting ML-2's structural steel is not the only way to protect it from corrosion.

Other methods, like hot-dip galvanizing or thermal spray metallizing, have grown in popularity in recent years. This growth has spurred debate over which method is best in light of engineers' and builders' push for corrosion protection that can last the lifetime of an asset—usually 50 years.

Actually, "best" is too vague to be helpful. Proponents of each method can furnish testing to demonstrate strong performance. But we know that galvanizing is a bit more expensive than resinous coatings on a per-square-foot basis. And we know that metallizing can be far more expensive; it also is more time-consuming and there is risk of incomplete coverage over complex geometries.

So anyone's lofty suggestion of a 50-year service life for corrosion protection is purely marketing. We wouldn't claim it, and no one should: No industry-accepted standard testing method evaluates 50-year performance for paint, galvanizing, or metallizing.

Presently, the only way to evaluate 50-year performance is to wait 50 years.

Coating choreography

On larger construction projects such as ML-2, the way corrosion protection is installed can matter just as much as material selection. When wisely chosen, it can create cost savings and compress construction schedules.

In some cases, applying coatings in the field makes the most sense. In others, it is more sensible to coat as much square footage as possible in the shop prior to shipment. Each project's individual circumstances drive that decision.

ML-2 is unique in that coating application is ongoing in three separate locations:

• Steel fabricator Paxton & Vierling Steel's shop in Carter Lake, Iowa
• PK Industrial's coating facility in Augusta, Kansas
• A temporary PK Industrial "shop" at Kennedy Space Center

It seems complicated, but this divide-and-conquer method was the right call to keep construction on track. For our part, it is essential that our team ensures the right amounts of the right products are manufactured consistently and arrive promptly to Iowa, Kansas, and Florida. An error here would cause costly delays.

Another countdown

Carboline's role in decades of NASA space missions has been modest but meaningful. It's the kind of working relationship we like best: A meeting of strong minds who exchange deeply technical information aimed at solving unique challenges.

Artemis IV is still years away from launching, but it's no time to relax. This isn't just a coatings project. We know what's at stake. And we know from experience how it feels to watch years of hard work pay off when the countdown hits zero, and to see our name in a footnote to a story like this one.

That never gets old.

Solution Spot | Carboline

Mon, 05 Feb 2024 09:18:42 -0500

Fully 120 years after the first cellulosic fire curve was published, it remains the basis on which building materials are tested for fire safety today.

It also is important in the scientific assessment of the performance of passive fire protection (PFP) measures.

But they don’t make building materials like they used to.

And, for all their performance and cost benefits, the modern synthetic or hybrid-synthetic materials common in our built environment today demonstrate that they don’t make fires like they used to, either.

Now, they’re worse. They ignite faster, they burn hotter, they release more toxic smoke, and they’re harder to fight. Fire loads have evolved. Is it time for fire safety test standards to do the same?

As the first in our series on the subject of modern-day fire loads and legacy cellulosic test standards, we elaborate on the debate surrounding the adequacy of these standards to assess the fire safety of today’s building materials.

Different fuels, different fires

The cellulosic time-temperature curve which formed the basis of what became the ASTM E119 (formerly C19) standard first appeared in 1903, and it turned fire safety from an art to a science. The curve shows temperature rise over actual time in conditions simulating a “standard” cellulosic fire, the primary fuel being wood.

Over time, industry has developed testing methods to understand how well common construction materials contain such a “standard” fire, and based on these materials tests, building code authorities regulate their use.

However, these standards were developed based on a 20th century understanding of fires and the wood, paper, and textile products that fueled them. While they have served as a fundamental benchmark for decades, there is an ongoing debate about their adequacy for assessing the thermal efficiency of fire resistive materials because today’s occupied spaces contain vastly different fuels than before.

A principal shortcoming of cellulosic test standards is that they do not adequately account for the behavior of synthetic materials, which feature much higher calorific potentials. The materials are everywhere: building components, home furnishings, and the long list of electronics inside practically every occupied space. In contrast, cellulosic materials tend to char and insulate better in a fire. These are no longer representative of modern building materials.

Ignition speed: Modern materials usually ignite more quickly than traditional cellulosic materials. The time it takes for a fire to reach critical stages is significantly shorter, meaning that occupants have less time to evacuate, first responders have less time to manage the situation effectively, and the applied stress on the passive fire protection measures intensifies. Cellulosic test standards were developed when fires took longer to develop, so their continued use as fire safety benchmarks can lead to a false sense of security in modern structures.

Toxic smoke and gases: Another critical concern is the toxic smoke and gases produced by modern materials during a fire. Cellulosic test standards primarily focus on temperature and flame spread but do not account for the release of hazardous gases from synthetic materials. These toxic emissions significantly threaten the safety of building occupants and first responders. This is particularly acute in electric vehicle, e-bike, and energy storage system hazard scenarios. These are discussed briefly below, as well as in Part 2 of this series.

Electric vehicles and energy storage systems: Product design and battery chemistry have converged to create a troubling threat scenario. The chemistry required for modern energy storage to be effective also burns quite hot and vents highly toxic gases in the event of a thermal runaway. Unfortunately, the very structural design elements that are meant to contain thermal runaways make it exceptionally difficult for firefighters to meaningfully contain them if those elements fail.

Time for different test methods?

The standards and methods we’ve questioned are essential to our work engineering cementitious and intumescent PFP products.

So, are they still useful? Do they need updating? Or, is it time to pivot away from cellulosic test standards in certain group occupancy classifications based on understanding of modern day risks?

Such a pivot would not mean wandering aimlessly: Industry already has other standards and methods that assess fire safety and material response in more intense fire events.

Our chemists use hydrocarbon pool and jet fire standards (for example, UL 1709, ISO 22899-1 or RWS) to develop products that can resist the intensity, erosive forces, and higher heat fluxes associated with rapid-rise and intense thermal scenarios to mitigate the time it takes for structural steel or protected substrates to reach critical limiting temperatures where structural integrity degrades and a local or global collapse could occur.

Of course, these standards were not meant for general occupancy environments. But we’ve shown that modern fire loads exceed the ability of these environments to meaningfully arrest or delay the spread of fire. Are we due a debate on the adoption of the more rigorous testing methods?

As you’ll read in part 2, which is coming soon, it might be that the debate is already settled.

Solution Spot | Carboline

Thu, 28 Dec 2023 11:45:25 -0500

Angelenos and their neighbors rely on a complex network of reservoirs, canals, and pipelines that bring water from the wetter parts of northern California to the parched basins and valleys of the south.

Protecting any water distribution infrastructure from corrosion is essential to its performance. But the stakes are that much higher when the basic habitability of an entire region depends on manmade infrastructure for a reliable water supply.

The Metropolitan Water District of Southern California’s (MWD) Etiwanda Pipeline is one piece of the region’s water puzzle. The 12-foot wide pipeline stretches 10 miles beneath the communities of Fontana and Rancho Cucamonga north of Los Angeles.

Inside the pipeline, a serious problem had emerged: The original cement mortar lining applied when the pipeline was first built in the 1990s had begun falling apart. And though the start of a rehab of the pipeline in autumn 2022 was welcome news, it took the pipeline out of service. Existing redundancies meant that water would still flow for customers, but relying on backups for primary supply is riskier the longer it persists.

MWD was clear that the work needed to be fast and efficient. And that was before it started raining.

Severe drought conditions led to mortar lining failure

The Etiwanda Pipeline’s original cement mortar lining was a perfectly adequate corrosion protection solution for its time.

But times have changed.

Mortar linings must remain damp for optimal performance, and for most water pipelines, that’s not a problem. But more frequent and more severe droughts across California left the Etiwanda Pipeline dry at times. In periods of no water, the mortar dried out and began to crack. When water again filled the pipeline, the force of its motion caused chunks of weakened mortar to break free.

The result: unimpeded corrosion of newly exposed steel.

During an initial phase of the rehab, MWD trialed various lining products from a host of manufacturers. Carboline’s Polyclad 767, a rigid polyurethane formula designed for water and wastewater pipeline and water tank lining applications, performed best and was specified for the remainder of the work. Its fast-cure properties would end up being critical to the project.

A firm 10-month timeline for the reline was agreed.

But before the new protective lining could go on, the old cement mortar needed to come off. This was as tedious as it was complex because the only way to remove it was by breaking it up into pieces small enough to lift out of manholes.

Crews from project contractor F.D. Thomas started by breaking the mortar off the pipeline with jackhammers and loading the waste into a motorized carrier. The carrier, which looks like a cross between a forklift and a tiny dump truck, would then make its way to the nearest manhole, where the mortar pieces were transferred to a conveyor and hoisted out of the pipeline piece by piece.

Surface preparation and lining application followed. Specialized rotary spray equipment would assure consistent application of the lining.

Crews moved methodically along the pipeline, manhole by manhole, mile by mile, 24 hours a day and five days a week.

The good and the bad of too much rain

The first months of 2023 were marked by atmospheric rivers that dumped intense rains across California and the western U.S. The storms brought with them severe floods and landslides, but they also erased what had been a deep drought.

With its reservoirs replenished, California authorities announced in the spring that water districts served by the State Water Project would be allocated 100% of the water they had asked for.

A 100% allocation is rare, so no water district in its right mind would turn it down. That included the MWD, even as its crucial Etiwanda Pipeline was out of service and would remain so for months.

The district had planned to return the Etiwanda Pipeline to service in October 2023, but in June they informed F.D. Thomas that they needed to press hard to finish as quickly as they could.

Now, spray crews were working nonstop seven days a week, knowing that the moment they finished, MWD would open the gates to more water than it had seen in years.

Polyclad 767 features prove critical to success

It’s challenging enough to staff up spray crews on short notice to deliver a project ahead of schedule. But adding to the challenge is that a crew must confront certain inherent limitations of the products they’re working with—limitations which can put a project’s desired schedule at odds with what’s possible on the ground.

Or, under the ground in this instance, and the limitations were cure time and recoat window. For the new polyurethane lining to perform as intended, two coats were needed. Polyclad 767 ended up being the perfect choice because its cure time is short enough that the crew applying the second coat could safely guide the rotary spray equipment over the first coat after a very short wait, and its recoat window is long enough that the crew wouldn’t need to wipe down or abrade the first coat to ensure the second coat would adhere properly.

F.D. Thomas crews’ blitz—made possible partly due to the characteristics of Polyclad 767—paid off. Lining application wrapped up a staggering two months ahead of the initial schedule.

MWD placed the Etiwanda Pipeline back in service in August 2023, in time to receive the water that millions in this region needed so badly.

Solution Spot | Carboline

Wed, 20 Dec 2023 15:02:34 -0500

At midstream oil & gas terminals around the world, quick-turn maintenance and emergency paint jobs are a constant in the business.

In Philadelphia, one terminal’s emergency doubled as a successful field trial for Carboline's new Carbothane DTM Mastic.

Carbothane DTM Mastic is a urethane-based hybrid mastic with excellent performance over minimally prepared surfaces and which requires no finish coat. Its mastic properties additionally offer some moisture tolerance during application; as a urethane, it retains its color and gloss longer and weathers far better than competing epoxy mastic maintenance coatings.

With Carbothane DTM Mastic, paint crews get in, do the job, and get out. And because the work holds up longer, you won't be seeing them back for a while.

Paint It Now, Or Pay a Fine

To comply with U.S. Environmental Protection Agency (EPA) regulations, American liquid terminals' piping must be white. But crisp white piping rarely stays that way for long, especially when located within a Delaware River port serving the Philadelphia terminal's heavy industrial neighbors.

Some sections of the piping contained rust on the surface of its existing coating. Other sections had a yellow coating applied as patches. Much of it was caked in stubborn grime because it was located inside a dyke where dirty water frequently pooled.

The piping was performing nominally, it just didn't look great. The EPA in July 2023 threatened to fine Kinder Morgan if they did not immediately repaint it.

Kinder Morgan's painting contractor, Ponns & Co., asked a Carboline sales representative to recommend the best product given that:

• The work had to proceed quickly
• The only surface preparation would be a pressure wash
• The coating needed to be applied by hand, not sprayed, to eliminate overspray risk
• The weather during application would be very hot with high relative humidity and dew points
• There was constant moisture in the vicinity of the piping

Our representative realized that these circumstances fit perfectly with the intended use of Carbothane DTM Mastic, which was then still in development. Ponns & Co. agreed to the trial, trusting the representative's instinct.

According to a Carboline report generated the day of the trial:

"The condition of the pipe is spots of bare steel and rust, and it is marginally cleaned. The pipe has been pressure washed but black dirt and debris remained on much of the underside of the pipe, especially closest to the ground."

"Contractor applied with whizz rollers and ½-inch (1.3 cm) nap rollers.The coating appeared to cover/hide very well.An area of yellow was overcoated and covered adequately in one coat. Film thickness build was checked and built to 4-6 wet mils with no runs observed. Most of application was being done at 2-4 wet mils overcoating the white areas. The film had a uniform appearance with no application issues."

Why a Successful Field Trial Matters

Carbothane DTM Mastic was successful in its trial-by-fire for the same reason it is a paint crew's darling.

Because it can be applied and cures properly in a wider range of temperature and humidity conditions, crews can begin applying it in the morning and work through the day without worrying about how changes in the weather will impact their work.

The product can also reduce the total amount of time and material needed for emergency and small maintenance jobs because it is designed to perform in a single coat. And as a urethane, that single coat still provides better weathering performance compared to an epoxy. This is a compelling bonus particularly for midstream oil & gas terminals or any other site containing pipe under the EPA's purview.

The pipe must be white, and with Carbothane DTM Mastic, it will stay white longer.

Solution Spot | Carboline

Tue, 12 Dec 2023 11:11:19 -0500

On the southeastern outskirts of Austin, Texas, where subdivisions surrender to farms, a factory three-quarters of a mile long sits beside a bend in the Colorado River.

This EV manufacturing facility contains a staggering 10 million square feet of floor space. It is the second-largest building by volume in the world—only a Boeing factory north of Seattle encloses more space.

Structural steel figured prominently in the EV facility's design, and building codes required that that steel be fireproofed. To achieve the required fire ratings, over half a million gallons of material were needed.

That’s a lot of material, and the aggressive construction schedule allowed no time for delay.

The challenge for specifiers was to choose high-performance fireproofing products under evolving construction conditions. There was no single silver bullet.

Here, there were two.

Scope and schedule drive PFP material selection and application

The fireproofing specification for this EV facility called for an intumescent product to protect structural columns and beams.

Generally, intumescent products cost more than their cementitious counterparts, but they achieve their ratings in a far lower film thickness and offer an aesthetically pleasing finish. Construction teams also encounter the question of whether applying fireproofing in the field or in off-site fabrication shops is ideal.

In Texas, specific project conditions drove the decision to specify a field-applied intumescent product:

Amount and type of steel – Structural steel components vary from rudimentary shapes (I-columns or -beams, or pipe or tube) to far more complex geometries. At the EV facility, the steel was quite simply shaped, which was one factor in the decision to specify field application. It’s easy to do and the risk of missing areas or not applying enough millage is comparatively low. Another factor was the huge amount of steel involved in construction. It was so much that no shop would likely have enough closed space or application equipment to be able to apply fireproofing off-site without becoming a significant bottleneck to the project.

Equipment – The equipment needed to apply a large volume of water- or solvent-based intumescent fireproofing in the field is smaller, more portable, and requires less energy than what is needed for cementitious products or intumescent epoxies applied in shop settings.

Cost – On a related note, shop application adds an additional layer of shipping. This added time and cost is an acceptable trade-off if complex steel geometry requires off-site shop application, but that was not a factor here.

Product formula – Intumescent products are formulated differently for different use cases. Variations in formula lead to variety in how they are applied as well as how they cure. On this project, specifiers needed to choose a product with a comparatively short cure time to maximize application throughput while minimizing on-site time for sprayers.

Based on these conditions, two Carboline products were specified: Thermo-Sorb VOC and A/D Firefilm III.

Thermo-Sorb VOC, a solvent-based intumescent product, went first. Sprayers applied just short of 400,000 gallons of it in all. It is rated for 180 days of exposure in general conditions, meaning it will cure as intended even when a building envelope is not enclosed. It also features a comparatively fast recoat time, allowing spray crews to work around the clock to apply two coats per day. It is especially suited for service in EV manufacturing facilities because it has shown strong resistance to chemicals commonly found in them.

(Thermo-Sorb VOC’s characteristics were instrumental in keeping another EV-related construction project on track in Quebec—read more from Canadian Manufacturing.)

A/D Firefilm III is a water-based product intended for application in enclosed spaces where moisture won’t intrude. This was applied to the remaining steel needing fireproofed, and application occurred once the building envelope was enclosed.

Protecting mechanical piping through thoughtful flexibility

Achieving fire safety ratings is just one aspect of many comprising personnel and asset protection at this EV facility. Another is preventing corrosion of the large-diameter chilled water piping serving the HVAC system there.

As progress continued at its rapid clip, the construction team realized that the pace of manufacture of the mechanical piping did not always match the pace of the crew installing it in Austin. This could have upset a delicate balance in which piping was supposed to be coated before it was hung. Complicating matters somewhat was the fact that some of the pipe was to be insulated, and some of it not.

The non-insulated pipe was to be protected by a standard three-coat atmospheric system consisting of products in Carboline's Carbozinc, Carboguard, and Carbothane product lines. Insulated pipe was to be coated with the Thermaline 450 series before the foam insulation and stainless steel jacketing was installed.

For optimum performance, these systems each require an abrasive-blasted surface to properly adhere. But because piping production and installation were occurring at different speeds, the owner and the construction team faced a choice: They could slow down installation, or they could keep hanging pipe, and find an alternative course of action for its protective coating.

The owner would not budge on the schedule. Speed to market is the prevailing motivator for EV manufacturers.

Abrasive blasting is not permitted inside an enclosed construction site unless it is properly contained. The EV manufacturer wanted to avoid an unplanned containment because the process takes up space and its setup and cleanup requirements cause delays. It’s also expensive, particularly when that cost is bolted onto a budget later instead of forecast in advance.

But quick-thinking Carboline technical experts offered an alternative: coat the installed bare pipe with Carbomastic 15, a high-solids epoxy amine noteworthy for decades of exceptional performance when applied to marginally prepared surfaces. It is particularly beloved in shipyards, where fleet owners have seen huge savings by dramatically reducing maintenance requirements when vessels are periodically dry docked (such as what happened with the Harvey Discovery in Louisiana—read this case study for more.)

Importantly for this project, Carbomastic 15 performs as well as the prior-specified products would have done, with the added benefit of being the best product in its class for minimally prepared surfaces. The construction team agreed to a change in the spec in real time. Ultimately over 1,000 linear feet (305 meters) of chilled water pipe was coated in Carbomastic 15, and no one missed a beat.

Strong partnerships keep the critical path intact

Applying fireproofing and protective coatings are critical path activities. Certain construction phases cannot begin until these are complete. The story of this project is the story of a construction team that was given flexibility—up front, but also on the fly—and performed well under immense pressure because of it.

Such immense pressure is becoming more the rule than the exception. All over the world, automakers, their suppliers, and governments are investing huge sums of money to ramp up EV and EV component manufacturing capacity quickly. It’s challenged architects, engineers, general contractors, and subcontractors to deliver this infrastructure in new ways.

They will be successful when they seek out and leverage the technical expertise of their suppliers. These collaborative partnerships are opening new doors in a building boom that will change the manufacturing landscape—and maybe society as a whole—forever.

Solution Spot | Carboline

Mon, 20 Nov 2023 09:36:08 -0500

Barges plying America’s navigable rivers play an understated but vital role in the economy.

If you’re moving non-perishable commodities in bulk, you won’t find a more reliable or cost-effective mode of transportation.

For this to remain so, owners and operators devote much energy and investment toward ensuring that their barges receive the maintenance attention they require with as little dry time as possible. A barge out of water is sunken money.

And a barge not returned to service on time owing to a clerical mix-up creates even more costly ripples.

But it doesn’t always need to be that way.

Testing a Worst-Case Scenario

Small things sometimes slip through the cracks, as was the case when a barge owned by a Louisiana-based shipper came due for a recoat.

The barge was dry docked between assignments in Houston, and a coating contractor began work. But there was a problem: The job’s spec offered no guidance for surface preparation of the voids’ steel plates or weld seams.

The contractor approached Carboline for assistance and presented these basic facts:

•A preconstruction primer had been applied to the steel prior to the barge’s final assembly
•Once assembled, the interior voids were pressure washed
•At this same time, the interior void weld seams were cleaned up

Pressure washing of pre-primed steel plate is rarely sufficient prior to applying a protective coating system. And weld seams are considered new steel, where an SSPC-SP 2 or SP 3 profile is advised for proper adhesion of any coating. Merely cleaning the weld seams would not result in an appropriate surface profile.

Instead of immediately recommending the conventional surface preparation, we proposed to do some science first. Carboline’s portfolio includes many products capable of strong performance over minimally prepared surfaces. How well would one of those products do inside this barge?

Carbomastic 15 and its variants are our best-performing product series for minimally prepared surfaces. Lamellar aluminum flakes included in its epoxy amine mastic formula impart superior barrier protection properties that asset owners across a wide range of industrial, civil, and marine applications have relied on for decades. That’s due to its flexibility: In addition to strong performance over minimally prepared surfaces, it has shown great performance over existing finishes as well as bare steel prepared to SP 2/3. It also performs well as a touch-up option over zinc-rich primers or galvanized steel.

The Houston contractor applied Carbomastic 15 FC—a fast-cure variant—as a spot primer over areas of bare metal. Then a full coat of the same product was applied to the barge’s interior voids. (In marine applications, we usually recommend the fast-cure variant for vessels already in-service undergoing maintenance. It’s a modest but helpful time savings compared to the straight Carbomastic 15, which we recommend for new construction.) Eleven days later, our technical service representative returned to glue on the dollies required to conduct adhesion pull-off tests according to ASTM D4541. We were back three days later to pull the dollies.

The Results

We know that Carbomastic 15 is a high performer over minimally prepared surfaces. But even our field team was surprised at the results.

The weakest reading recorded was 703 psi (4,847 kPa) on the plate bearing the barge’s name and weight. Average dry film thickness (DFT) here was 6.48 mils. Our representative recorded in the field report from the test that the coating was 60% cohesive with 40% mill scale. It is not surprising that the weakest reading was recorded so near to where the barge’s identification information was welded onto the plate.

The strongest reading was 1,962 psi (13,527.5 kPa) on the roof plate at 6.93 mils DFT and 100% cohesion. Again, no blasting or power tool cleaning was done here. The only preparation was a high-pressure wash.

Why It Matters

Anecdotally, something between 700 and 1,200 psi (4,826.3 to 8,273.7 kPa) would be considered sufficient adhesion for a typical coating system over ideally prepared SP 2 or SP 3 steel in a barge void.

We are not saying that contractors should ignore surface preparation guidance. And our message to owners is not that you should pressure contractors into cutting corners. Surface preparation guidance exists for good reason.

But this case shows that marine vessel maintenance projects do not need to be ruined by a paperwork error. Our testing demonstrates that with the Carbomastic 15 series, an owner can anticipate at least sufficient adhesion, and more probably exceptional adhesion, over marginally prepared surfaces.

The implications involving reduced cost and downtime, improved labor efficiency, and accelerated throughput in shipyards are obvious, and obviously compelling.

Solution Spot | Carboline

Fri, 17 Nov 2023 17:15:33 -0500

Port Fourchon is not the end of the world, but it is at the end of Louisiana.

Harvey Gulf International Marine is among the many firms whose fleets dock here. Locals know a Harvey ship by its striking blue livery. The firm’s ocean supply vessels (OSV) shuttle supplies, equipment, and crews back and forth between deepwater Gulf oil rigs and the mainland.

The Harvey Discovery is one such vessel, measuring 256 feet (80.8 meters) long and 58 feet (17.7 meters) wide, and capable of carrying 3,500 tons (3,557.2 metric tons) on her 8,700-square-foot (808.7-square-meter) cargo deck. It’s hard, expensive work to protect her hull from corrosion. That work must be done efficiently and cost effectively if her service is to turn a profit because neither Harvey Gulf nor any maritime transportation company is in this business just for the pleasure of it.

And Harvey Gulf is certainly pleased about the maintenance cost savings they’ve seen which are the result of a crucial decision made just before the 2011 repaint of Harvey Discovery’s hull.

Carbomastic 15 on the Harvey Discovery

Until 2022, U.S. federal regulations required that OSV owners like Harvey Gulf dry dock their ships twice every five years.

Even if that mandate annoyed owners, from a corrosion protection perspective, that’s an appropriate frequency. An owner or operator would be very, very happy at eight years of service life for a hull coating.

It is more likely that hulls are totally repainted every five years or less. Even when they are properly prepared and coated, their service environment is incredibly corrosive. Most of the time, our field personnel see hulls covered in blisters, a signal that the coating has failed.

That’s most of the time. But it’s not all of the time. And certainly not for Harvey Gulf, who has dramatically reduced the amount of labor, time, and cost expended every time Harvey Discovery is hoisted out of the water.

2011 Repaint

The Harvey Discovery hull was repainted for the first time in 2011, five years after the ship was first laid down. It was a full repaint, requiring abrasive blasting to SSPC SP 6 on every square inch of the hull before new coatings were applied.

Blasting and recoating the hull of a 265-foot OSV is long, expensive work. It can take a six-person crew up to six days to complete and cost $150,000 to $180,000.

Could that cost be reduced? Could that time spent out of revenue service be compressed?

The answer wouldn’t come from blasting differently. Instead, it came from choosing a different hull primer.

Carbomastic 15 FC is a fast-curing epoxy amine mastic primer. Its superior barrier protection qualities come from the lamellar aluminum pigment; it’s been long trusted to protect assets against corrosion in extremely harsh environments. (We recommend Carbomastic 15 FC—the faster-curing variant in this product series—for maintenance activities where time is short. Straight Carbomastic 15 is recommended for new construction.)

Of course, this decision was not the sort that pays off immediately. It would be years before Harvey Gulf could judge whether it was the right call.

2014

The first signs of success emerged when Harvey Discovery was dry docked in 2014.

After cleaning via power washing, paint crews observed only a negligible amount of damage to the hull coating. These localized areas were slurry blasted and spot primed, followed by a routine application of anti-fouling.

A Carboline field technical service report from this episode stated that slurry blasting, priming, and application of anti-fouling occurred over the course of just two days.

2016

We next viewed Harvey Discovery almost exactly two years later, when she was again dry docked to receive a new anti-fouling coating.

Our inspector reported “the hull had little to no blistering” despite being five years since its last full repaint. The hull was pressure washed, small areas around the pad eyes were spot primed, and the anti-fouling treatment was applied.

2018

Harvey Discovery was out of the water again in late 2018 to receive repairs to her stern thruster.

Curious of the state of her hull, our inspector returned to the shipyard. He observed no defects of any kind in the coating. Aside from a normal amount of marine growth below the waterline, the condition of the hull appeared unchanged.

2019

We returned to the dock the following spring to assist in spot repairs to Harvey Discovery’s coating, primarily above the waterline and along her bulwarks.

Images attached to the technical service report generated from this visit show that the hull was still in excellent shape. No defects were observed and no touch-ups to the coating of any kind were recommended.

2021

In December 2021, we paid our most recent visit to Harvey Discovery. Paint crews were working on more bulwark areas requiring localized blasting and touch-ups.

The hull remained in great shape. As with the prior inspection, no defects were recorded and no repair or maintenance coating was needed on the hull.

As of this writing in late 2023, Harvey Discovery continues in her service on a hull primer applied in 2011.

And while we’re thrilled about the product performance, Harvey Gulf must be thrilled at the amount they’ve saved by repeatedly not blasting and entirely recoating Harvey Discovery’s hull. It’s easily half a million dollars.

On the strength of the performance of Carbomastic 15 FC on Harvey Discovery, Harvey Gulf has begun using the product for hull recoats as each of its ships comes due. Multiply that savings by a fleet of 52 vessels and see what happens to the bottom line.

Subchapter M and the Case for Carbomastic 15

There’s even more at stake than product performance or money saved.

A new U.S. Coast Guard rule related to towing and other vessels is designed to further reduce the burden on vessel owners. Subchapter M describes the criteria that will allow for underwater inspections of vessels and change the rule from two dry dockings every five years to just one for saltwater vessels.

In our view, the Carbomastic 15 series of primers for saltwater service represents a tremendous opportunity for shippers who are driven to reduce the time and expense of dry docking by increasing the likelihood of passing underwater inspections.

Even more fundamentally, it’s a way for shippers to keep aging fleets in service longer. OSVs are complex feats of maritime engineering; for up to $80 million and a monstrous amount of energy, you can have one built new.

But the most sustainable vessels are the ones already on the water. And when they’re well protected, they also turn the best profit.

Solution Spot | Carboline

Thu, 19 Oct 2023 16:25:04 -0400

As construction of EVs and associated battery manufacturing facilities ramps up, one thing is clear: Automakers, governments, and the market all want these complex factories commissioned fast.

It’s easy to see why.

With the dollar value attached to these projects, what builder wouldn’t work their hardest to finish under budget and pocket a percentage of the savings?

And then there’s the strong demand among practically all stakeholders to reduce reliance on fossil fuels. Even the notoriously risk-averse automotive OEMs are shelling out billions to help build these facilities, a clue that they are confident in a significant return on the investment.

Finally, governments are lately generous in incentivizing the rapid scale-up of EV and battery manufacturing capacity. Grants and cheap loans make it a no-brainer for ownership groups to race to qualify for a seat directly in front of the public money hose.

What’s all this got to do with stopping water vapor transfer (WVT)?

Concrete flooring is instrumental to the anatomy of EV assembly plants, battery manufacturing facilities, and battery recycling operations. This sector’s building boom will draw in a greater and greater share of specifiers who are likely unfamiliar with the phenomenon, much less what they can do to prevent it under intense deadline pressure.

I see a knowledge gap opening up. Let’s try to close it.

Coating "Green" Concrete: A Red Flag?

New concrete contains water, and it won’t cure unless that water escapes.

If a concrete floor coating is applied before the concrete cures, WVT is likely to occur. The water must go somewhere, and it takes the path of least resistance. Often, that is upward through a concrete slab. If a coating is applied to concrete too soon, WVT can lead to blisters and bubbles that indicate it has come unstuck from the substrate.

ASTM’s D4263 (plastic sheet), F1869 (calcium chloride), and F2170 (relative humidity) testing methods were developed to help applicators be certain that concrete is sufficiently dry before applying a coating.

Construction teams have been frustrated by the basic facts of concrete’s cure process for about as long as concrete has existed. Thoughtful phasing and staging of construction has traditionally helped sidestep the frustration, and to a degree it still does. But today, that’s not enough.

Increasingly, construction programs emphasize working over “green” concrete, which has empowered specifiers with greater latitude in selecting more costly specialty concrete formulas containing quick-cure additives or densifying agents so that curing time is reduced.

Schedule savings beats material savings every time, right?

Here’s the problem: Just as additives influence concrete cure characteristics, concrete formulas influence the application and performance of protective coatings.

For one example, some curing accelerators are made of materials containing crystalline structures that reduce the porosity of concrete. Is the specified floor coating formula compatible with the concrete? Will it stick?

For another, the addition of densifying agents reduces the amount of water needed in a concrete mix. Less water needing to escape means a faster cure, which allows crews to resume work on newly poured concrete sooner. But denser concrete also makes it much harder and more time-intensive to achieve the proper surface profile a coating needs to adhere properly. Does the schedule account for those added labor hours? Does the budget accommodate the extra equipment and materials that are warranted?

And don’t forget about the potential that additives will influence the compressive strength of concrete. Some concrete floor coating manufacturers—my own employer included—refuse to allow application of their products unless compressive strength testing results exceed 250 psi (1,724 kPa).

Innovations in protective coating technology have a role to play. One which I find particularly exciting is Dudick’s Vapor-Stop. The product depends on water to cure properly. Want to guess where that water comes from? Of course, it isn’t the universal solution to WVT. Nothing is.

The point is, if it’s still risky to work over green concrete, then at least it’s less of a red flag today than in the past. Project management has improved with the adoption of more coordinated construction delivery methods. And construction teams today are equipped with more advanced materials that allow them to turn old ways of thinking and building upside down.

But the Big Question Remains

Where, really, is the savings?

In EV and EV battery facility construction, today’s specifier plays a critical—if perhaps hidden—role in securing fast, efficient, and profitable construction delivery. But they will not find the answer here.

They will find it when they leverage the emerging coalitions of specialty concrete coating manufacturers and applicators who work together to bring better overall value to construction projects.

So it’s up to the folks like me to say, “Hey, we’re here, and here to help.”

Solution Spot | Carboline

Tue, 17 Oct 2023 17:05:33 -0400

Summary

Controlling soluble salts is one of the largest challenges faced during the surface preparation portion of a coating project. Failure to remove soluble salts can drastically shorten a coating’s lifecycle. On this episode, Ken Rossy, President of HoldTight, joins us to discuss the differences between atmospheric and immersion services, the debate on allowable soluble salt limits, and how additives can help. All of this and more coming up next on The Red Bucket.

Timestamps

0:00 - Intro
1:36 - Introduction to Kon Rossy
3:17 - Introduction to HoldTight Solutions
6:34 - Why are Salts Detrimental to Steel?
8:38 - “Invisible” Contaminants and How to Find Them
13:18 - Cleanliness in Immersion and Atmospheric Service
19:51 - The Debate About the Amount of Allowable Soluble Salts
25:59 - Using Additives to Remove Salts and Hold Cleanliness
35:46 - "The Four Questions" [Non-Technical]
39:54 - "Tech Tips"
40:21 - Closing Remarks

Solution Spot | Carboline

Tue, 03 Oct 2023 15:47:17 -0400

The Mexican state of Quintana Roo—and the Caribbean waters just offshore—are an ecological and historical treasure.

The ocean here is clear and warm. Sun-seeking tourists love the beaches. Inland jungles support immense biodiversity and contain, here and there, white stone ruins marking the principal settlements of the ancient Maya.

Locals know well another highlight of the coastal landscape, one which the rest of us usually overlook: mangrove forests. One of them, the Sian Ka’an Biosphere Reserve, is so critical to the regional ecosystem that it became a UNESCO World Heritage Site in 1987. Its name comes from the Yucatec Mayan language and translates to English as “gate of heaven.”

So when a real estate group began building two resorts on property dominated by mangroves not far from Sian Ka’an in 2016, the project needed to balance the practical concerns of construction against strict mandates to minimize environmental impact.

Together, the resorts total nearly two million square feet of lodging, dining, entertainment, and spa service space. Fireproofing was required for the resorts’ structural steel, and given this unique environment and the rules in place to protect it, selecting the right products was essential to success.

The Right PFP Portfolio

Mayan culture inspired the design for the resorts. The idea, according to the architecture team, was to evoke the mysticism and richness of this indigenous culture while immersing guests within the predominant ecological feature of the property: a vast mangrove forest.

But to achieve the reward of bringing travelers in such close touch with the mangroves, building crews made a substantial effort in ensuring their preservation.

For our part, it meant helping to specify the ideal passive fire protection (PFP) products from our comprehensive portfolio.

A total of seven Carboline PFP, primer, and topcoat products were specified, reflecting the wide variety of settings and circumstances in which fire protection was required: Some structural steel would be protected from external exposure, but some would be exposed to the elements; some would be hidden from view, but some would be prominent.

One of the primer products specified was Rustbond, a flexible epoxy amine. It is an extremely high-solid formula ideal for use when environmental or occupational safety concerns prohibit the emission of volatile organic compounds (VOC).

The other primer specified on this project was Carbomastic 615, an epoxy phenalkamine most traditionally applied in marine applications. In addition to its excellent saltwater corrosion resistance and ability to cure under water, it was an ideal selection on this project because it can be applied on marginally prepared surfaces. It was applied in areas where environmental rules prohibit abrasive blasting.

Southwest Type 5MD medium-density gypsum-based cementitious fireproofing was applied to structural steel members in closed interior spaces. It is the economical choice to achieve fire rating requirements provided frequent or prolonged exposure to moisture can be prevented.

Southwest Type 7GP Portland cement-based cementitious fireproofing was applied to structural steel members in semi-exposed (though not visible to guests) locations where high humidity and contact with moisture was anticipated.

A/D Firefilm III intumescent fireproofing was applied to structural steel members located in guest-facing spaces where aesthetic appeal was desired. Intumescent fireproofing products appear much like paint and are far more appealing to look at compared to cementitious products. A/D Firefilm III contains very low VOC content and is LEED-compliant.

Carboguard 890 VOC, a highly chemical resistant epoxy mastic coating, was applied as a primer on decorative steel members. It was followed by Carbothane 133 HB, a high-build polyurethane finish coat chosen on the strength of its resistance to chemical exposure and abrasion in addition to coming in a wide range of colors.

Quiet, Comfortable, and Safe

One of the two resorts—the St. Regis Kanai—opened in spring 2023. The other, known as Edition Kanai, will open soon.

Far from being Spring Break, early reviews from its first guests proclaim St. Regis Kanai as a place for peace and quiet.

Carboline can’t take credit for that. We can take some for helping make the resorts safe.

And we’re also proud because that safety was achieved without sacrificing the ecosystem these resorts were meant to honor.

Solution Spot | Carboline

Tue, 03 Oct 2023 15:47:17 -0400

Las aguas del Caribe en la costa de Quintana Roo, son un tesoro ecológico e histórico. El océano aquí es claro y cálido, los turistas que gustan del sol y adoran las playas, encuentran aquí el lugar ideal para descansar, en esta misma zona se encuentra una inmensa biodiversidad y antiguas ruinas de piedra blanca, que marcan los principales asentamientos de los antiguos mayas.

Para los visitantes, esta zona ofrece hermosos lugares como la Reserva de la Biosfera Sian Ka'an, declarada Patrimonio de la Humanidad en 1987 por la Unesco, su nombre en Maya significa "La Puerta del Cielo". Esta zona ha generado a través de los años un modelo de desarrollo económico y social, que integra al sector turístico, pesquero y académico, en un marco de sustentabilidad, reconocido a nivel internacional.

Así que cuando estos dos proyectos se empezaron a diseñar en 2016, no muy lejos de Sian Ka'an y en un área rodeada de manglares, era necesario tanto para los arquitectos como los ingenieros, poder equilibrar las preocupaciones prácticas de la construcción, con las estrictas necesidades técnicas que les permitieran minimizar el impacto ambiental.

En conjunto, este complejo suma casi 4,600 metros cuadrados de espacio interior y exterior, a través de distintivas áreas de alojamiento, entretenimiento y eventos. Aquí la protección contra incendios para el acero estructural, era una parte clave de la ingeniería del proyecto y dada la ubicación única y las reglas establecidas para protegerla, la selección de los productos adecuados era esencial para su éxito.

El portafolio correcto para protección pasiva contra fuego

La cultura maya inspiró el diseño de los complejos; su idea era evocar el misticismo y la riqueza de esta cultura indígena, mientras sumergía a los huéspedes en la atmósfera predominante de la propiedad; un vasto bosque de manglares.

Pero para lograr la recompensa de acercar a los viajeros de esta manera a los manglares, los equipos de construcción hicieron un esfuerzo sustancial para garantizar su preservación.

En nuestro caso, significó ayudar a seleccionar los productos ideales de protección pasiva contra fuego (PFP) que cumplieran con los altos estándares de seguridad que requería la estructura y ofrecer al mismo tiempo soluciones estéticas y funcionales.

Se especificaron un total de siete productos PFP de Carboline para ambos complejos, tanto primarios como acabados que cumplían con la variedad de entornos (internos y externos) y requerimientos de las áreas a proteger.

Uno de los primarios especificados fue Rustbond, un primario penetrante reticulado con excelentes propiedades de humectación, es altamente flexible, tiene buena resistencia a los químicos y solventes, acepta una gran variedad de capas de acabado, además que cumple con las regulaciones de VOC y tiene un bajo olor.

Otro primario especificado fue Carbomastic 615, una resina epóxica de alto desempeño que tiene una excelente resistencia a la exposición al agua dulce y salada, tiene un curado rápido y cumplía con el requisito de algunas áreas donde no se permitía el proceso de sandblasting por cuestiones ambientales.

Además de esto se aplicó Southwest 5MD en estructuras de acero expuesto, este cementicio de densidad media, se seleccionó porque ofrecía la solución más rentable, además de cumplir con los criterios de desempeño que la construcción requería, esto permitió una amplia flexibilidad para adaptarse al diseño y criterios de construcción, en áreas semiexpuestas se aplicó Southwest 7GP donde se anticipaba una alta humedad y se requería alto desempeño físico para áreas expuestas donde se requería una contención más duradera.

Para espacios interiores se seleccionó Firefilm III, este intumescente de película delgada base agua, está diseñado para proporcionar un acabado altamente estético, duradero y rendimiento inigualables, estos espacios requerían largos tiempos de protección contra fuego y un contenido muy bajo de VOC, otra ventaja es su compatibilidad con LEED los productos de esta categoría contribuyen al diseño y construcción de infraestructuras ambientalmente sustentables.

Como acabados se seleccionaron Carboguard 890 VOC y Carbothane 133 HB, que gracias a su variedad de colores permitían adaptarse a las necesidades de pilares y estructuras visibles del proyecto. Estos recubrimientos brindan alta resistencia en ambientes abrasivos y es apto para aplicaciones sobre una variedad de primarios y capas intermedias de Carboline.

Tranquilidad, comodidad y seguridad

Uno de los dos complejos, el St. Regis Kanai, abrió en la primavera de 2023. El otro, conocido como Edition Kanai, abrirá pronto. Las críticas de sus primeros huéspedes definen al St. Regis Kanai como un lugar de paz y tranquilidad.

Carboline no se puede llevar el mérito por eso. Pero podemos llevarnos algo de crédito por ayudar a hacer que los complejos sean seguros. Y también estamos orgullosos porque esa protección se logró, sin sacrificar los lineamientos de diseño, ni al ecosistema que estos complejos estaban destinados a honrar.

Solution Spot | Carboline

Wed, 13 Sep 2023 15:50:31 -0400

Over the course of a tank car’s normal service, it is inevitable that its user will need to consider repairing its lining.

But when, whether, or how to do it is not always straightforward. A constellation of factors influence the nature and extent of damage to a lining. Building from that, the nature and extent of damage may require something other than a repair.

It’s a lot to unpack, but we’ve unpacked it here.

This is the final part of a three-part series on rail tank car linings. Part 1 covered lining product selection. Part 2 covered inspection of tank car linings.

Common Reasons to Repair a Tank Car Lining

How to approach a tank car lining repair depends on the defect affecting the lining. The risk of a defect, or even the premature failure of a lining, can come from any of the following:

• Unintended damage to the lining during loading, unloading, maintenance, or cleaning
• Mechanical or chemical wear sustained in the normal service of the tank car
• A flaw in the manufacture or application of the lining

The most common tank car lining defects an inspector might observe include:

Blistering - This bubble-like defect of the lining may emerge within or beneath the film of the lining. It can occur immediately after application or within days, weeks, or even months later. Blisters are typically caused by improper surface preparation, the presence of surface contaminants, solvent entrapment, incompatible service, extreme temperatures, or improper cleaning.

Cracking - The cracking of a tank car lining is usually found in areas subjected to flexing or other types of movement of the steel. This is normal and expected stress, so if cracking appears, the likely culprits are too-high film thickness or a poor profile achieved during surface preparation. In rarer cases, cracking can occur if the tank car shell sustains exceptionally harsh stress.

Mechanical damage – This physical damage to the tank car lining usually occurs during loading, unloading, maintenance, or cleaning. For instance, impacting the lining with hoses, ladders, tools, or cleaning apparatus are common causes of mechanical damage. Dislodging clogs or even inserting probes to assess cargo levels can also cause mechanical damage.

Off-ratio lining materials – If a tank car lining is a two-part system, the improper measurement or mix of parts A and B will prevent the lining from curing as intended. If that happens, cargo could stick to the lining. Two problems can follow: One, that portion of the lining may never cure and instead fail. Two, constituents of the uncured lining may leach into the commodity and render it unsaleable and useless.

Corrosion staining – This phenomenon occurs when a tank car lining is improperly applied, or when no lining is applied at all. For one example, corrosion staining is common if unlined or improperly lined tank cars haul highly acidic commodities. For another, it can occur if the specified lining is generally incompatible with the commodity. Expect to see corrosion stains form in the vulnerable areas of a tank car shell, including its safety valve, nozzle, threaded ports, or weld seams.

Commodity wear – A common vector of commodity wear damage is the impact of the lining by frozen cargoes. For example, 83% ammonium nitrate solution freezes at 150°F (65.5° C). Certain sulfur formulas freeze at around 194°F (90°C). If the temperature inside the tank drops below the freezing point of the commodity, the frozen chunks that form as a result can bang against the lining, causing it to chip.

All the scenarios above are common, but that doesn’t mean tank car operators should remain solely reactive to lining defects. The proactive search for process improvements is a low-cost, high-impact way to protect the condition of tank car linings and keep cars on the rails longer.

Tank Car Lining Repair vs. Relining

Once the extent and nature of defects have been defined following tank car lining inspection, the next step is to determine whether to repair the lining or replace it with a new one. Use the simple chart below as a starting point.

REPAIR OR RELINE?	TYPE OF DEFECT	EXAMPLES
RELINE	Defects covering a large surface area or that will continue to spread	Major blistering of the lining, such as from a chemical attack Lining delamination from substrate Significant flaking, rusting, off-ratio material, or mechanical damage
REPAIR	Isolated defects that do not cover a significant area and will not continue to spread	Mechanical damage Small holiday areas Minor blistering, corrosion rusting, or off-ratio material

But there’s more nuance to the decision than merely assessing the size, amount, or severity of tank car lining defects. Consider these additional questions:

• How old is the lining and what is its expected service life?
• How old is the tank car?
• When does the car's lease terminate?
• When is the car due for requalification?

The answers may further justify a repair or a reline, but they may also point to a third way: If a tank car with a damaged lining is very old or is nearing its mandatory requalification, it may be sensible to do nothing and place the car into service carrying benign or inert cargo. Of course, this is only possible with larger or more flexible fleets.

Federal Mandates for Rail Tank Car Maintenance

In the U.S., federal law mandates that tank car linings must receive periodic inspection or requalification when the hauled commodity has a corrosion rate exceeding 2.5 mils (64 microns) per year on mild steel. Most liquid commodities shipped by rail fall into this category, including chlorides, sulfides, fertilizer solutions, other oxidizing agents, and crude oils. In addition, the updated HM216B regulation expanded requirements for rail transport of hazardous commodities.

A periodic lining inspection is not required for commodities that are considered “non-corrosive,” such as glycols, corn sweeteners, solvents, and phenol. In these cases, inspections may be performed at the discretion of the tank car owner based on product purity requirements.

Because tank cars are considered a permit-required confined space according to 26 CFR 1926, an entry permit is required and the interior environment must be monitored for proper air quality.

Proper Surface Preparation for Rail Tank Car Linings

To ensure safe entry, a tank car must first be thoroughly cleaned to remove any contaminants from the substrate and achieve a neutral pH level. The extent of this cleaning process will depend upon the previous service and degree of coating failure. Even if a tank car appears clean, previous cargoes may have settled onto the substrate.

If this is the case, the substance must be removed to prevent contamination of the blast media, osmotic blistering, or interference with coating adhesion. The surface should also be tested for contaminants like oils and non-visible soluble salts, especially if the car carries acidic or alkaline commodities.

If additional cleaning or neutralization is required, the appropriate method will need to be repeated before the final blast is performed. Depending on the nature of the previous service, this may include prebaking, steam injection, hot water wash, or chemical cleaning.

Once the interior is clean, abrasive blasting to SSPC-SP 5/NACE No. 1 comes next. This may include vacuum blasting, open blasting, or power tool cleaning with a bristle blaster. Open blasting is not typically recommended for isolated repairs given the higher risk for collateral damage to the lining.

Next, the edges of the repair area must be feather sanded to reduce the film thickness. Based on the required film thickness, the blast profile may be specified at a minimum of 2 mils (51 microns) and as high as 4.5 mils (114 microns) depending on the product specified. For example, baked phenolics require a smoother blast profile of approximately 2 mils (51 microns). After interior blasting, the tank car must be cleaned of all debris, dust, and loose abrasive by vacuum or dry brush.

Application & Curing Process for Tank Car Lining Repair

For optimal performance, it is critical to follow the proper application and curing process. The lining should be applied according to the specified film thickness. For example, baked phenolics are applied at a dry film thickness of 5-8 mils (127-203 microns), while most epoxies are applied at 12-15 mils (305-381 microns) and vinyl esters and epoxy novolacs are applied at dry film thicknesses in excess of 20 mils (508 microns).

Carboline’s Plasite 9060 has been used rather extensively to repair tank cars lined with baked phenolics. A low-bake lining like Plasite 9085 is ideal for sulfuric acid immersion service, while Plasite 4550 S is used to repair linings for crude oil service both in the shop and in the field.

Our innovative burst pouch is also available for railcar linings like Plasite 9060, Plasite 9573, Plasite 9085, Carboguard 992, and Carboguard 995. Burst pouches are ideal for small repairs: They contain only 10 ounces (283 grams) of product, so applicators can easily use only the amount of product they need and avoid the needless cost of whole buckets of product and the time it takes to prepare them. Each of the pouches is filled with the exact right amount of product so that, once burst and properly mixed, there is zero risk of an improper mix ratio.

During application, it’s important to consider how ambient conditions will impact the curing process. Air-dry coatings such as epoxy novolacs can take several days to cure, especially during the winter months in colder climates. In such cases, repair shops opt for force cures to speed up the process.

In more recent years, mobile repair units have emerged that make field repairs of tank car linings more convenient. While this helps to reduce out-of-service time for a tank car, mobile repair units tend to lack the in-house baking capabilities that support force cures, often resulting in longer cure times depending on ambient conditions.

As a final step, a thorough inspection of the lining should be performed to verify that proper film thickness has been achieved and the coating is free of any holidays.

Depending on the service, haulers expect tank car linings to last a minimum of five to 10 years. However, if properly maintained and repaired over the course of its service life, an interior lining could provide decades of protection both to the tank car and its important cargo.

Solution Spot | Carboline

Wed, 06 Sep 2023 12:58:21 -0400

Solution Spot | Carboline

Tue, 22 Aug 2023 02:59:25 -0400

Summary

On this episode of The Red Bucket, Pete Mitchell from GMA Garnet joins us as we explore the various factors of abrasive blasting that contribute to long-term coating performance. The industry has focused on cleanliness and profile for years, but a new study suggests that peak density could be the largest contributing factor. We talk about all of that and more coming up next on The Red Bucket.

Timestamps

0:00 - Intro
2:33 - Introduction to Pete Mitchell
4:39 - Introduction to GMA Garnet
6:08 - The Advantages of Garnet as an Abrasive Blast Media
9:36 - Friability
15:58 - Blast Cleanliness vs. Profile
22:40 - Density vs. Depth
28:51 - What Engineers and Specifiers Need to Know About Abrasives
35:08 - "The Four Questions" [Non-Technical]
38:00 - "Tech Tips"
39:16 - Closing Remarks

Solution Spot | Carboline

Tue, 15 Aug 2023 12:48:19 -0400

Carbozinc 11 is a time-tested corrosion-resistant coating that provides excellent galvanic corrosion protection to steel in some of the harshest environments. For over five decades, Carbozinc 11 has been the industry standard for high-performance inorganic zinc protection on steel structures worldwide.

Solution Spot | Carboline

Mon, 14 Aug 2023 12:17:52 -0400

On May 25, 1961, President John F. Kennedy asked Congress to commit to landing a man on the moon before the end of the decade, raising the stakes in the Space Race.

NASA’s Saturn V launch vehicle would be the workhorse of the Apollo Program. It was the largest spacecraft ever designed. But before the super-heavy rockets could lift off, the agency needed a building of immense scale in which to build them. Construction of the now-iconic Vertical Assembly Building (VAB) began in August of 1963 at what we know today as Kennedy Space Center.

Completed in 1966, the VAB remains one of the largest buildings in the world. Made of structural steel, it is 52 stories high, stretches 515 feet (157 meters) wide, and covers eight acres (3.2 hectares) of land.

All that structural steel inside the VAB as well as that specified for the launch arm/umbilical towers needed to be coated to prevent degradation.

However, its location in Florida is one of the most corrosive coastal areas in the country due to the combination of ocean salt spray, heat, humidity, and frequent precipitation.

If climate, weather, and geography weren't enough, with every mission launch comes high volumes of acidic exhaust, making the area at and near the launchpads even more corrosive. These conditions made coating system selection particularly challenging.

Carbozinc 11, and shipped to the laydown yard at Cape Canaveral. It was erected and touched up with additional layers of Carbozinc 11.

We know now that Carbozinc 11 is the industry’s superior inorganic zinc primer, but in the mid-1960s, it had only been on the market for around a decade. No one knew for sure how long it would protect the infrastructure at Complex 39, but through accelerated corrosion testing, a service life of 50 years was predicted.

Prior to our development of Carbozinc 11, zinc primers had to be cured using a post-cure solution sprayed onto painted steel members in a cumbersome two-step process. Carbozinc 11 allowed the steel to be fabricated, blast cleaned, primed, and then handled almost immediately after priming, speeding up fab shop processes.

The product was a game-changing innovation during the industrial construction boom of the 1960s.

SSPC Charles G. Munger Award, granted for an “outstanding industrial or commercial project demonstrating longevity of the original coating,” for the 50 years of protection at Complex 39.

The VAB was the first and most historically significant project on which NASA and Carboline collaborated. Many more followed, including coating with Carbozinc 11 the Space Shuttle Mount-Dismount Device at Vandenberg Air Force Base in California.

Nearly 60 years later, Carbozinc 11 is just as reliable as it was in the early 1960s. It set the standard then, and has been the standard ever since.

Solution Spot | Carboline

Tue, 08 Aug 2023 15:39:50 -0400

Proper inspection of rail tank car linings has always been crucial to safe, reliable shipment of commodities by rail, but it is especially timely now.

The rapid increase in crude oil production in North America in the middle of the last decade kicked off a tank car building boom. Federal law mandates that tank cars carrying flammable commodities be requalified every ten years. It also stipulates that owners develop an interior lining inspection regimen commensurate with a car’s ordinary service on an interval not exceeding eight years.

There will be more rail tank car linings inspections now and for the next handful of years than at any time in history.

With more inspections due, more inspectors will be needed if railcar owners or operators hope to return their rolling stock to the rails quickly.

This is Part 2 of a three-part series. Part 1, which covered proper tank car lining product selection, is here.

Visual Tank Car Lining Inspection

Visual inspections of tank car linings occur right after a tank car is lined for the first time, and then periodically according to the inspection regimen mentioned above.

While this is a comparatively subjective and simple inspection method, it is still a good one. Usually, if a lining appears free of any defects, it is in good condition.

In fact, during tank car requalification inspections, a satisfactory visual inspection of a lining is enough to “pass” and the additional tests described below are not ordered. But if defects like protrusions, rusting, staining, blistering, or paint runs are plainly apparent, further testing is warranted to determine the degree of lining failure.

SSPC-PA 2 using a verified, in-date, and calibrated gauge if a failure of the lining is observed during an in-service visual inspection. Inspections proceed this way:

An inspector begins the test at the B-head (this is the end of the tank car with the hand brake) and takes five to 10 readings moving in a zig-zag pattern from as high as can be safely reached and working down toward the floor. Each reading is numbered as it is recorded. This is repeated ring by ring, working counter-clockwise until the inspector returns to the B-head. It is important to number each reading as it is taken because readings relate to an approximate location on the tank car interior.

DFT tests can additionally be ordered during a tank car’s requalification if a lining failure is observed during visual inspection. If no failure is observed, DFT readings are not necessary.

Holiday Testing

Another common testing method is the holiday test. Holiday tests utilize specialized instruments that detect discontinuities such as pinholes and voids in protective linings applied to a conductive substrate.

Holiday testing is neither ordered during routine in-service requalification nor when a premature failure of a lining is observed. The test is only conducted after a car is lined for the first time to verify coverage of an applied coating or lining.

According to the NACE SP0188 standard, a low-voltage wet sponge tester should be used for any DFTs recorded below 20 mils, moving at a rate of one square foot per second on double pass. A high-voltage spark tester should be used for DFTs exceeding 20 mils, moving at one square foot per second on single pass. The holiday test must be performed over the entirety of the lining. Once a holiday is detected, it must be marked and documented.

Documenting Rail Tank Car Lining Inspection Findings

Inspections are worthless if findings are not thoroughly and legibly documented.

A careful description of out-of-spec DFT readings and a detailed accounting of the amount and nature of holidays are critical. Inspectors should review their findings with colleagues or supervisors. In our view, more minds reduce inspector bias and result in the strongest possible inspection report.

After all, a strong report is the basis for what comes next, whether that’s a repair of the lining, a total reline, or even a recommendation that the car be removed from service.

Repairing tank car linings is covered in the third part of this series, which will be published soon.

Solution Spot | Carboline

Tue, 08 Aug 2023 08:36:56 -0400

Few products we encounter in life or business are regarded as industry standards. Even fewer hold such high esteem for decades in a row.

We think Carbozinc 11 is one of those rare products. It’s stood the test of time because the assets it protects have done the same.

Nowhere is this staying power more evident than in the case of two bridges in Missouri.

First, learn how Carbozinc 11 was applied as an experimental alternative coating on a highway bridge in rural New Haven, Missouri.

Then, read about its selection as part of a bridge replacement project 50 years later and 64 miles away in suburban St. Louis.

Comparing a Cost-Saving Alternative

Missouri Highway E meanders through parts of Franklin and Gasconade counties, past the woods and farms of wine country.

The highway meets Pin Oak Creek just southwest of the small town of New Haven. A new bridge built in 1969 to cross the creek was the scene, in October of that year, of an experiment.

Instead of coating bridge A-2107 in the three-coat lead-based alkyd system the Missouri Highway and Transportation Department (MHTD) normally specified, the Department—now called MoDOT—had specified Carbozinc 11, an inorganic zinc primer that had demonstrated exceptional corrosion protection performance.

One reason for the change was that the three-coat system that had been the standard of the time was slow and cumbersome to apply. Another was that it was leaden. Better, less toxic alternatives had emerged, and it was time to try one in Missouri.

In addition to evaluating the Carboline product, MHTD also wanted to test airless spray application of the coating. No contractor in Missouri prior to that point had used airless spray equipment.

Whatever MHTD or the coating applicator thought of Carbozinc 11 or airless spray application at the time is lost to history. We only know that inspectors kept a close eye on certain areas of the bridge’s steel beams where small amounts of rust had formed. A memo from July 1970 remarked that “badly painted areas were spotty and small and were mostly in areas which were masked from the direct spray by some sort of protrusion.”

The rest of the coating was apparently in great shape. Follow-up inspections in 1971 and 1977 confirmed this, as did an inspection in 1989 initiated by Carboline’s own Tom Calzone. Tom had wanted to see how well the coating held up after 20 years of no maintenance.

“Corrosion was estimated to comprise less than 1 percent of the surface” of the bridge, according to a story Tom co-wrote with an MHTD representative in the April 1990 Journal of Protective Coatings & Linings.

Not bad.

And even better, Tom went back to New Haven a decade later, just before the bridge’s first repaint. Of this visit, he wrote, “My inspection of September 1999 discovered well under 1% rust with the condition hardly changed from my last visit 10 years earlier.”

He also remarked on how three decades of exceptional performance translated to an appealing lifecycle cost. According to his calculations, 30 years after Carbozinc 11 was applied to bridge A-2107, the cost per square foot per year of this corrosion protection had dwindled to just half a cent in 1969 dollars.

“Remember, this was the Missouri crew’s first airless spray application and their first inorganic zinc application,” Tom wrote. “They are still using inorganic zinc today.”

Corrosion Protection for a Crucial Suburban Road

Sixty-four miles east of bridge A-2107 and 50 years later, MoDOT again specified Carbozinc 11 for corrosion protection on a new bridge.

Midland Boulevard is a vital thoroughfare in north St. Louis County, connecting some of the metro’s mature inner suburbs to arterials and highways as it winds its way northwest. At the U.S. 67 interchange, it turns into Dorsett Road, a high-traffic commercial and industrial roadway connecting the community to Interstate 270.

The overpass that originally carried Midland/Dorsett over U.S. 67 was built in 1970, the year after bridge A-2107 was laid across Pin Oak Creek near New Haven.

But while little has changed on Highway E, a great deal has changed in suburban St. Louis County. Over the years, continued growth in population and economic activity brought more people, more vehicles, and more freight here than the 1970 bridge could bear. MoDOT announced the bridge would go out of service for a full replacement during the summer of 2019.

“(The bridge) is more than 45 years old and is in deteriorating condition,” MoDOT told the community. “Due to the existing condition of the bridge, it needs to be replaced.”

Its replacement is a standard-seeming four-lane, two-way highway overpass, and its steel is protected by the industry-standard inorganic zinc primer.

Things are a lot different today than in 1969. There are few constants. But one of them is the exceptional performance of Carbozinc 11.

Solution Spot | Carboline

Wed, 19 Jul 2023 11:38:24 -0400

From the early 1940s until 2020, people in Charles County, Maryland, and King George County, Virginia, crossed the Potomac River on a rudimentary two-lane, two-way bridge named after Maryland Governor Harry Nice. Thousands depended on it daily for both work and recreation.

However, throughout the 2010s, functionality and safety issues began to cause concerns. With only one narrow lane in each direction, traffic frequently became congested. Additionally, inspections showed irreversible structural degradation of the bridge. Calls for its replacement became louder, and the Maryland Transportation Authority (MDTA) began construction of a new bridge in July 2020.

Carbozinc 11-HS is an ultra-low VOC inorganic zinc primer that offers unparalleled corrosion resistance while meeting some of the most stringent VOC restrictions. Specifying this Carbozinc variant was crucial for a successful shop application emphasizing air quality and applicator safety.

Carboguard 893, which was specified as an intermediate, is fit for service either over bare steel or over inorganic zinc primers. It can be top-coated with a broad range of high-performance finish coats.

Carboxane 2000 is an isocyanate-free, ultra-durable coating that provides outstanding color and gloss retention as well as excellent corrosion protection for exterior exposures. While asset protection is always the primary function of a coating system, certain assets—like high-traffic bridges—must also be pleasing to the eye.

Carbozinc 11 has a long track record of exceptional performance for generations. MDTA’s specification of this product in its coating system showed they were serious about counting on this key transportation asset deep into the future.

In-Shop Application

The MDTA specified in-shop application of all three coats, first because containing the structure over the water would be a huge cost, and second because shop-applied coatings are easier to inspect prior to erection.

Additionally, there are many other benefits to in-shop application, including:

• Coating in a temperature- and humidity-controlled environment
• Faster and safer overall application
• Reduced labor requirements
• Reduced liability costs due to lower injury risk

Back to Business

Named the Nice/Middleton Bridge, the $463 million construction project was completed ahead of schedule and opened to traffic on October 12, 2022.

Now that the bridge meets 21^st century traffic demands, drivers and bicyclists alike cross the Potomac every day with ease. And they weren’t the only ones who recognized a job very well done. In 2023, the project earned AMPP’s Eric Kline Award for Outstanding Achievement in Coatings Work in a Fixed Shop.

But most importantly, with Carbozinc 11’s lasting protection, the MDTA can rest easy knowing the coating system is expected to last well into the 2060s.

Solution Spot | Carboline

Tue, 18 Jul 2023 02:59:25 -0400

Summary

Previously on The Red Bucket, we began our exploration into all things concrete with our friend and AMPP Instructor, Paul Kennington. This month, we continue our conversation with Paul, discussing moisture effects, inspection, testing standards, and when to coat the concrete. All of that and more are coming up next on The Red Bucket.

Timestamps

Click to follow along with the transcript:

0:00 - Intro
0:58 - Moisture and Concrete
6:02 - ASTM F1869: The Calcium Chloride Test
9:03 - ASTM F2170: The in situ Humidity Probes Test
13:08 - Visually Inspecting Concrete
17:26 - CSP Standards
20:18 - When to Coat Concrete
23:50 - "The Four Questions" [Non-Technical]
26:04 - "Tech Tips"
26:45 - Closing Remarks

Transcript

Intro

Jack Walker: If you missed last month's episode, Coating Concrete (Part 1), be sure to listen to it before continuing. And now, we'll dive back into the conversation.

Moisture and Concrete

Jack Walker: There's a great document, I call it the Bible for coating concrete. It is the NACE No. 6/SSPC-SP 13. This document carries not only what you need to do before you go coat the concrete, it gives you how to inspect it afterwards, and pretty much references all the relevant ASTM standards that will help you. And it contains, I would say, the 80/20 rule: 80% of everything is there, there are some things outside of there, and, probably, I'd even give it 90% or 95%. But there are some other methods, and we'll talk about that.

Paul Atzemis: It's a good rule. Not the exception, but the rule.

Jack Walker: Correct. It's got almost everything you need to know, and I think one of the things that it starts with is the inspection of concrete before you do anything. Let's talk a little bit about moisture and concrete, and why moisture can be a problem.

Paul Kennington: Well, especially if you have coatings that are very sensitive to moisture. Wrong coating system. And epoxies probably are the most tolerant, but you also have other things that you can do, and the simplest way I always tell somebody is to do the Plastic Sheet Method. You use a little Visqueen 18x18 square, you put it at every 500 square feet, and it'll tell you, but that's moisture vapor and Plastic Sheet Method, and relative humidity probes typically are only very valuable when you get into an enclosed building, where we have HVAC: heating, ventilation, and air condition. That's going to work because Mother Nature likes to hit an equilibrium. So, that's where we run into a problem. Now, when you get outside, when it can be diffused in all directions, that's where it gets much tougher.

Jack Walker: So, let's talk about that MVT (moisture vapor transmission). So, that's basically a problem when you have slab-on-grade, and you have moisture, and usually cold, in the ground, and the warmer air above that slab, it wants to pull the water through the concrete up into that drier air. So, you have the damper soil, drier air.

Paul Kennington: But that's how we have rain. Right? Same process. Yeah. So, if you think of it as rain, how does that happen? Same thing can happen with our concrete substrate. And, so, we have ways that civil engineers can design. Here's the problem that we have with concrete: designing is only part of the issue. It's the implementation of placing it the way that it should be. So, many times what we'll do is we'll put a moisture barrier down that will minimize or mitigate moisture from transmitting to your earth, and it's only anywhere from two to six mils. But, placing it is where the problem comes in. It gets holes punched in it, from the chairs or from people not paying attention, or something's in their way, or they ignore it. So, we have that problem, but just as moisture will rise to make rain, so does it come through the concrete, and that's where we have problems. And then it brings all those uglies: calcium, salt, whatever is left in the concrete because concrete's not a fully reacted material. In fact, some civil engineers will state that it still reacts as much as 25 to 30 years later. And, so, with that in mind, we have those physical properties going on, and it's difficult for a coating. Typically, if it's 3000 psi Portland cement, your surface tensile strength is about a 10% value of 300. And so that's how we rate coatings if it's acceptable for concrete because if you put an epoxy coating on and it has far greater properties, and you do a pull test, the concrete will fail at wherever its weakest plane is. So, with that in mind, that's why the most common Portland cement design is 3000 psi because it'll take. Now, when you get on highways or superstructures, it all changes, but still, what we see in our industry is that it's generally Type 1, 3000 psi Portland cement.

Paul Atzemis: When people ask me, "What kind of adhesion values do you want to see?" my answer every time is, "Honestly, I don't care what the number is, as long as it's concrete failure." The concrete should fail because all of the coatings are going to exceed 300 or 400 pull-off adhesion. So, typically, I'm like, "No, I just want to see concrete on the back of the paint. When you pull it, that's what should fail."

Jack Walker: And so that NACE standard, the plastic sheet test is the first moisture test that it gives us, and like you said, I always recommend that people do it first. It gives you an idea of a pass/fail criteria of whether or not you have moisture. No indication of what the level of moisture coming through is. Just "Do I have moisture?"

ASTM F1869: The Calcium Chloride Test

Jack Walker: So, that's really where the next one comes in, the F1869, the calcium chloride test. Now, we can get a rate. Let's talk a little bit about that test.

Paul Kennington: Yeah, The National Tire and Rubber Association says that we should not exceed three pounds per thousand square feet in a 72-hour period. If you're not an engineer or you're not into math, you say, "What does that mean?" Well, basically, it's a quantifiable figure that once you measure the calcium chloride disc, you measure it, seal it, and then after so many hours, you take it off, re-weigh it, and there's a mathematical calculation that they use, and what they have found is that if it doesn't exceed three pounds per thousand square feet in that period of time, chances are, your coating that you put on it will not fail. But it doesn't say that if you don't have impurities in your concrete, because every time you have a chemical reaction, you give off a gas. And, so, that's where sometimes we see blisters and bubbles in coatings, because, we have to remember, most of the things that we paint concrete with are plastics.

Jack Walker: So, one thing I think that I always tell people about the calcium chloride test is everybody's bought a pair of shoes, and in that shoe comes a little packet. That little packet is a moisture, scavenger, you know, it absorbs moisture. And so, when it absorbs all the moisture, that's the same way that calcium chloride does. You said you measure, well you weigh.

Paul Kennington: Yeah, and we call that adsorbent rather than absorbent.

Jack Walker: Right, and that calculation that sounds weird is really just how we talk about that rate, you know? When you talk about cars, miles per hour. And if you didn't understand that, or kilometers per hour, that would be weird. But the three pounds per 24 hours per thousand square feet really is because that's how long you run the test. That's how frequently you place the test itself, and then that three pounds is your rate. And, so, it sounds very convoluted, but the standard is very clear on how you get that calculation.

Paul Atzemis: And the calculation, although it is math, it's pretty straightforward. When you buy any of these kits, it is literally "Plug in the first number, plug in the second number, subtract, and multiply here." It is literally step-by-step. And honestly, it is the same thing, we put new hardwood floors in through our house. You go to the hardwood floor suppliers; they sell this kit. Anybody who works over a concrete substrate puts anything over it.

Jack Walker: Slab-on-grade.

Paul Atzemis: Well, I mean, anything over concrete, because if you're elevated over an area that has a high moisture content, that concrete's going to absorb it.

ASTM F2170: The in situ Humidity Probes Test

Jack Walker: And so the third test is the F2170, the in situ humidity probes. Let's talk a little bit about the difference there, because, you know, we have pass or fail with the plastic sheet. We now have a moisture vapor transmission rate with calcium chloride. Now we're talking about humidity.

Paul Kennington: Right. And, so, there's where you get into a misnomer because if there was never a Visqueen, you could do it today, during a dry season, and you could get very good results. And then, during a wet season, you can get very poor results. And I've seen that happen to where it gets into a "He said, she said" type of thing.

Jack Walker: Well, I think that's an important point to bring up. All of these are a snapshot in time. You brought up condition space where we really have a problem. Well, when you are doing these tests, if, let's say, you're doing new construction, if the final area is going to be conditioned, you need to run these tests in that exact scenario. You can't run the test when the building's all open and expect it to be the same when the building's closed.

Paul Kennington: Because moisture travels with the least resistance. That's part of life. And so, if you're not confined at the time that you do these tests, the tests only capture that snapshot of that particular time's conditions. And if you're in the summer, let's say you're out in the desert, it may not show you any problems, but you enclose this, and many times buildings add humidity. And then you've got the differential of the soil versus the climate inside of the building, and it could be a 20-degree difference or more. And, so, when you try to reach equilibrium, you have a problem. And, so, there are companies out there that specialize in mitigating moisture and concrete, and, with that in mind, you have to understand that it's very expensive to do that.

Jack Walker: I think one of the things that's important for our listeners to know is that just because you maybe reach a high level, so, with the calcium chloride test, it's no more than three pounds per 24 hours per thousand square feet, for the relative humidity test, which just tests the humidity within concrete, we don't want it to be any more than 80%. But the asterisk there is that's for standard coatings. There are coatings that are designed for these things, and, as you said, there are some epoxies out there that are specifically designed for this. But really, I mean, what I love are urethane cements. You're putting a cement on a cement, and, historically, urethane cements are unaffected by moisture vapor transmission, and I think it has to do probably with the porosity of the urethane cement itself. And, so, it gives a place for that moisture to go. The epoxies are rigid, they're tightly cross-linked, they're too dense. The urethane cements, I think I've said it on this show before, but I've definitely said it in the concrete presentations that I give frequently, is that a different guy that I knew who had been in the resinous flooring world for years, used to always say, "If you want to have problems, use epoxy. If you want it to go smooth, use urethane cement." And that's not an indictment on epoxy, because epoxy is still the most widely used coating material for concrete, and it is great, but when you get any of these high moisture vapor situations, you really need to be using specialty epoxies. If you're going to be using epoxies. I think that does a really good job of summing up water and MVT and the problems that you're going to have there.

Visually Inspecting Concrete

Jack Walker: So, when we're inspecting concrete, there's also more to it than that, too. Sometimes, you can visually see, when you walk in, not new concrete at this point, but maybe we're coating aged concrete. You can walk in and visually see some contaminants and things like that.

Paul Kennington: Well, we said earlier that typically concrete will have around 12 to 13 pH freshly poured. Well, if you come across the surface and the pH is below nine, I'd have a concern. If you come across areas where the pH has above a 12, I'd get really concerned, because that means they've probably been dumping chemicals that are high alkaline in nature. The acid side of it goes after the cement portion, and they'll actually neutralize each other. But the other problem is with high alkalines, and we say, "Oh, well, concrete's high and alkalinity anyway," but here's the problem that we have, is that the sodium hydroxide and those hydroxyl groups, and any other type of high pH materials, will go after inorganic matter, such as rock and sand. And, so, if you take the rock and sand out, then all you have is a porous structure, like a sponge. And, so, I have seen many times where they say, "Well, the pH is 13," and I say, "Have you done a petrographic study?" And, so, sometimes, if you know it's a caustic deck, for example, where they're going to expose it to high pH surfaces, look at it. And, so, you want to see how deep you have to go. And you may have to do a small core sample to see how deep you have to go to reach the physical properties again because it's typically not all at once that concrete fails, it fails from generally the exposure area down.

Jack Walker: And sometimes you walk into a place, and you just see that before you even begin to do anything, you can see the damage to the concrete. You can see oils, greases, things like that, they're very visible to see, and they have to be dealt with. And, traditionally, oil-contaminated concrete, if you're going to coat that, that meant that you're removing concrete down to non-contaminated concrete, and that's still a method that is used today. There are some products on the market, though, that are advertised as microbial, that will eat the oil and things like that, and those are used with some success. But really, when you get into these things because concrete being a sponge, there's nothing you're going to do to get that oil out. It's usually two, three. I mean, it sucks in inches down.

Paul Kennington: So, what you try to do is just get your surface clean, and then maybe do a pull test to make sure you're going to exceed the bond string because if you're looking to remove that stain, chances are you're going to be removing concrete, and the owner's not going to be happy with you.

Paul Atzemis: I worked on a project where that was exactly what it was, and the spec read that all traces had to be removed, and they did the analysis, and it came back, and, fortunately, no, partially fortunately, it was a ridiculous thickness slab of an old, old building. It was like 18 or 24 inches was the slab. But they came back, and they said, "We need to remove eight inches of concrete to get rid of all of this. Is that truly what you need?" And we had to look at it and say, "Let's do an adhesion test, get it as clean as we can, go through all of our cleaning processes, let it dry out again, and let's do an adhesion test. We'll do a spot. Can we live with that analysis, or are you removing eight inches, a third of your concrete slab, and repouring?" And, it turns out, adhesion was fine with what we had to do, and they said, "Yep, we can live with that."

Paul Kennington: Yeah. There's where I would say, "Make a tank inside of a tank." Do what you have to do, mechanically attach something, and then put your chemical-resistant barrier on top.

Jack Walker: And I think after inspection, and you look and you're figuring out, "Okay, now we've gotten the concrete, we know we can coat it, now we have to do the surface prep." And steel, it's kind of easy, here's all these cleanliness methods and standards, and we're going to give you a profile and a measured profile, and, if you've ever blasted concrete, you know, it's not even, there's not an even profile that you really can measure.

CSP Standards

Jack Walker: And, so, one of the things we really look to, and this is a great contribution to the industry from the International Concrete Repair Institute, and that's the CSP standards. Let's talk about how great those are for a minute.

Paul Kennington: Well, they're quantifiable. That's what I like. I mean, you can actually take from CSP 1 all the way, is it the seven or nine?

Jack Walker: Nine.

Paul Kennington: Nine, okay. And, so, typically, and it depends on what kind of conditions you're going to go into, whether if you specify three to five, five to seven, or seven to nine, if you're going to be in constant immersion and it's going to be thermal cycling, you'll probably want seven to nine.

Jack Walker: A deeper profile, and then I think a good way to talk about that is that when you get these standards, they are rubber forms. It's a visual standard that isn't just a picture. Now, they do have pictorial standards that they can show you, and those are easy to find and readily available and don't cost any money. However, the thing that every inspector should have if they're doing concrete jobs is, especially if it's specified this way, and specifiers should definitely be using this method to guarantee that you get the profile needed, because, as we know, for steel, and we've talked about profile and coating thickness and everything else is so important. We're increasing the surface area so that we can get better adhesion, and we're going to need more surface area depending on the harshness of the environment and so these standards are 3D. There's no question whether or not the surface profile that was desired, whether it was achieved or not, with these standards.

Paul Kennington: Well, and what does profile mean? Well, we hope to remove the laitance, that's one of the things that means. And we hope that it removes any impurities left on the surface, which could be part of the laitance, but we also hope it gives us a roughened surface so that we can have good surface area to bond to. But, with all that in mind, if the concrete doesn't meet the physical properties, we know that the coefficient of thermal expansion of concrete versus coatings is totally different. And, so what we hope to, by doing proper surface prep, just like we do with epoxy coatings on steel, we do the same thing with concrete, is that if there's thermal stresses, it's passed through the film rather than at the bond interface, and that's the most crucial thing is the bond interface. And we know that the concrete's going to be weaker than coatings. That's just a known fact, you can look at physical properties. So, with that in mind, if the contractor can do the best that he can do under the circumstances that he's placed in, then chances are you may have a long-term success.

When to Coat Concrete

Jack Walker: And we've talked a lot about concrete. We've had a good conversation here today, and I think there's one more tip I want to include before we wrap things up is, because this is: when should we be coating concrete? Like, what time during the day?

Paul Kennington: As I heard a concrete expert say one time, he said, "Even though concrete is inorganic, it is a livable, breathable thing." We do know, we've discussed it earlier, it is a sponge. And, during cooling situations, we take in air and moisture into the concrete, and, during warming situations, we expel it, and that's outgassing. That's one of the problems that really can be exacerbating when you're trying to coat concrete. When do we do it? Well, there are several methods that people go about. One is to get a facet primer and coat it when the concrete temperature becomes stable or starts to decline, and then sometimes there's a chemical reaction going on in the concrete that none of us know about, and I've seen it happen, and it could be from below the concrete. But we should plan on always priming, at a minimum, when the concrete temperature is stable or descending. And, so, that may only require you to work one night or two nights if it's a secondary containment area to get it primed. Because, the other thing is, you've got to keep in mind that no one covers the surface a hundred percent. The effective bond area, probably at best, will be 92% to 94%, even with a very efficient crew. And, so, you still have the potential for outgassing, and outgassing is generally when the concrete is warming. There's a thing called off-gassing, when there's something going on below the surface that may be due to the fact that the concrete has impurities in it, like AAR or ASR, that the moisture is being consumed, and it keeps it reacting. So, there are many things that we can't give an empirical answer, as much as we'd like to, and, so, many times, it requires test patches to see what will happen. But I can tell you right now, outgassing is the enemy of coatings.

Paul Atzemis: And, Paul touched on it a little bit, as we talk about that difference in temperature and what draws the moisture or the gases through the concrete, even if you're coating at the right time of day and the temperatures are cooling, if you're applying a coating that has a high exothermic property, it could start that process again. So, it's not a guarantee that "Just because I painted at midnight, all things are great." You could still have problems.

Paul Kennington: That's why you need a thin film penetrating impossible primer. Because if you bridge, which you're going to do because most of our epoxies today are very high solids, and if you bridge and it starts going through an exothermic reaction, it only takes a two to three-degree differential in temperature to start outgassing in concrete. That's the thing people say, "Well, it didn't go up much. I only went up one degree."

Paul Atzemis: That's 50% of what you needed.

Jack Walker: As you guys can tell, Paul Kennington, not Paul Atzemis, well, Paul Atzemis knows what he's talking about too, but Paul Kennington is definitely well versed in this. If you have any questions for him, again, you could reach out to Paul Atzemis at technicalservice@kingfeat.com.

"The Four Questions" [Non-Technical]

Jack Walker: But now, we're going to do what we do with all of our guests, and we're going to get into what we call our four questions segment. So, Paul, what's your favorite movie or TV show?

Paul Kennington: I would say The Green Mile is my favorite movie.

Paul Atzemis: Oh boy, that's a good one. I mean, a little Tom Hanks. What's your favorite hobby? When you have free time on your hands? I know your schedule, and that doesn't happen very often, but what do you like to do in your free time?

Paul Kennington: Lately, I've been really into home remodeling, you know? I enjoy that, when you start from nothing, from the wall up, plumbing and all electrical. I've enjoyed that as a part of my retirement package, and it's enhancing my home as far as value, but it also gives me something to do to stay out of trouble. What's the old saying? Idle hands or the Devil's workshop.

Paul Atzemis: You spent a lifetime working with concrete, and now you get to play with some other materials, huh?

Paul Kennington: Yeah. And some concrete, yeah.

Jack Walker: You're a wrestler or a baseball player. You're coming out to the ring; you're coming up to home plate. What's your walkup song?

Paul Kennington: Uh, Lord bless me. I need your help.

Jack Walker: That sounds like an overly confident answer. Just kidding.

Paul Kennington: No, because you never know what's going to be thrown at you. Literally.

Jack Walker: Yeah, literally. All right, we got one more, Paul.

Paul Atzemis: Yeah, last one. You're a Houston native, so I can guess where this is going to go. But if you were watching a sports game, a team, what do you follow? What do you like to watch?

Paul Kennington: The Astros. I mean, that's a natural. And of course, the Texans, I mean, you know, the only advantage we have over the St. Louis group is that we still have a team.

Jack Walker: Yeah, I don't know if I'd rather not have a team than have the Texans.

Paul Kennington: Well, you know, literally, there's always hope.

Jack Walker: Thank you, Paul, so much for coming on the show.

Paul Kennington: Oh, thank you for inviting me.

Jack Walker: I appreciate it as always, as you guys can tell, I love this man. He has taught me so much about coatings, and I'm glad that he was able to come on the show.

"Tech Tips"

Jack Walker: Up next is our "Tech Tips" segment.

Jamie Valdez: You have questions. They have answers. This is "Tech Tips."

Brian O'Connor: This is Brian O'Connor with Carboline Tech Service. When coating concrete, it is important to remove the laitance layer of the concrete as that is the weakest link in a system if applied to. A properly mixed coating will adhere to the surface, but if that surface is not sound, the surface can delaminate. If you ever see the coating delaminate and there is concrete on the backside of the coating, the coating did its job and adhered as designed. However, the surface preparation or concrete integrity is the failure.

Closing Remarks

Jack Walker: Thank you again for listening to this show. We'll see you guys in another month.

Solution Spot | Carboline

Mon, 10 Jul 2023 15:22:48 -0400

Rail tank cars are essential to global distribution networks.

They’re a safe, reliable, and comparatively cheap way to move a huge volume of commodities where they are needed.

One contributing factor to their safety is the protective linings applied inside rail tank car shells. Proper selection of interior linings ensures years (and sometimes decades) of protection against corrosion of the tank car substrate and purity of lading in transit.

This is Part 1 of a three-part series. Additional articles in this series will cover tank car lining inspections and lining repairs.

How Cargo Shapes Rail Tank Car Lining Selection

Industrial processes rely on pure, uncorrupted commodities to assure final product quality. That purity is doubly important when the products are meant for human consumption and are therefore heavily regulated by health and safety authorities.

Rail tank car linings are effective in maintaining this purity provided they are selected to match the chemical characteristics of the commodity they’re meant to protect. (We confine this discussion to liquid-applied products. Solid linings—rubber being the prime example—are not considered here.)

Epoxy linings (including amine, polyamide, cycloaliphatic, novolac, or phenolic epoxies) in general perform well against a wide range of exposures and so are the most commonly specified lining systems.

Baked phenolics offer excellent resistance to acids and solvents and are commonly specified for tank cars hauling non-corrosive material. These are uniquely well-suited for hauling phenols, which are important ingredients in medicines, plastics, and explosives. As the name implies, these thermoset linings require an elevated temperature for full crosslinking. That process takes several hours at a minimum, and up to several days depending on what product is specified and how many coats are applied. Read more about baked phenolic railcar linings here.

Vinyl esters are specified when cargo is more corrosive than epoxies can withstand, but not so corrosive that a rubber lining is needed. Sodium bisulfate and sodium chlorate are common ladings for rail tank cars lined with vinyl esters. Thick-film vinyl esters are often specified as maintenance linings.

Thermal requirements impact lining selection, too. Very hot or very cold conditions will influence lining performance.

Treat the generic information above as a conversation starter with a coating manufacturer or applicator. These experts will consult product testing information and field performance history to direct you to the lining product that’s best for a tank car’s intended service.

Do Substrate Condition and Remediation Influence Rail Tank Car Lining Selection?

Federal regulations mandate tank car lining inspection cycles that are intended to catch and address lining failures or corrosion when the corrosion rate of a commodity is equal to or greater than 2.5 mils per year.

Typical rail tank car lining products are formulated to last longer than the maximum eight-year mandatory inspection interval for cars carrying corrosive commodities in the U.S., but design life and service life don’t always match. Any combination of the following can result in lining failure:

• Errors not detected or addressed during manufacture or application of the lining
• A car entered multiple service by mistake and hauled cargo incompatible with its lining
• Improper cleaning of the tank car between services
• Mechanical or thermal damage during service compromised the lining

What’s more, lots can happen in the interval between inspections and requalification. Linings often hold up just fine after their first inspection, or two, or even three. But you can see the potential problem: The more inspections a lining passes, the more likely a problem will occur prior to the next one.

And whatever the reason why, these linings fail. When that happens, the steel beneath them is likely to degrade.

In the U.S., federal law regulates how much material loss a rail tank car can sustain and still qualify for service. Maintenance lining systems are available for application over pitted or otherwise corroded steel that fill in voids and prevent additional damage from occurring. Then, a traditional lining is applied.

Selecting the ideal system is more complicated in this case. In addition to understanding a lining’s compatibility with cargo, coating manufacturers or applicators must also contend with its relationship to the product applied to the substrate.

The difficulty can be avoided with a thorough review of tank car decontamination processes, lining application methods and product selection. The best maintenance is prevention, especially regarding the most intensely corrosive commodities.

Proper Lining Selection Only Goes So Far

Selecting the right rail tank car lining is not always easy. You’ll get better mileage in partnership with knowledgeable coating manufacturers and qualified applicators.

So, you’re one-third of the way there.

Inspecting the lining is the next leg of the journey. That’s in Part 2 of this series, which we'll publish soon.

Solution Spot | Carboline

Mon, 10 Jul 2023 10:28:45 -0400

In May 2023, the U.S. National Transportation Safety Board (NTSB) did something it almost never does.

It published an urgent notice to state and federal agencies with findings from an investigation it had yet to complete.

Citing the January 2022 collapse of the Fern Hollow Bridge in Pittsburgh, Pennsylvania, the notice urged authorities nationwide to “review inspection reports and identify incomplete follow-up actions that need to be resolved for bridges made of uncoated weathering steel.”

“NTSB investigators found corrosion, deterioration, and section loss on all four of the bridge’s legs due to the continual accumulation of water and debris,” the Board wrote.

The bridge legs were made of corten steel, also known as weathering steel, which typically is not coated. The oxide layer that forms on its surface naturally in reaction to atmospheric exposure protects it rather well, very much like the green patina that forms on copper.

Corten steel has a long and generally successful service record for bridges and other infrastructure around the world. So what happened in Pittsburgh? Why was this different?

The Collapse and Investigation

The Fern Hollow Bridge carried Forbes Road over a ravine at the north end of a local park. A light snow was still falling when it collapsed about an hour before dawn on Jan. 28, 2022.

Four cars and a city bus were on the bridge when it fell 100 feet (30 meters) down into the ravine. A fifth car drove off an abutment after the collapse. It couldn’t stop in time. Four people were hurt in the collapse, two of them seriously.

It didn’t take long for investigators to develop a theory of the cause. According to a supplemental report accompanying their urgent notice, the NTSB “found extensive corrosion damage and deterioration” of the bridge legs.

Worse, that damage was not new. “Starting in 2005, each of these (National Bridge Inspection Standards) inspection reports documented corrosion damage and deterioration of the bridge legs, including the most recent inspection report” which was filed four months before the collapse.

Laser scans of the corroded portions of the bridge legs supported empirically what was plainly visible to anyone who had looked: The bridge legs had suffered an alarming loss of thickness. In some areas, where there had once been a web of steel, only fist-sized holes remained.

Technical Service Engineers as your best resource here.

But before you do anything, thoroughly inspect corten steel assets. And if those inspection reports urge action, then act.