One of the most costly challenges in the petrochemical industry today is managing corrosion under insulation (CUI) and corrosion under fireproofing (CUF). The most simplistic description of corrosion on steel is rust.

The vast majority of steel corrosion consists of an electro-chemical reaction converting the iron into an oxide. This type of corrosion is most typically prevented or controlled with the use of coatings, galvanizing, or grounding.

The second-largest type of steel corrosion is from chemical attack. This type of corrosion can be prevented or controlled with the use of coatings.

NACE (National Association of Corrosion Engineers) estimated in NACE International News, March 8, 2016, that the “global cost of corrosion at $2.5 trillion annually.” For some countries, this is a significant portion of their GDP. Energy Skeptic reported on March 26, 2016, that in the U.S.:

• $1.4 billion annual loss due to steel corrosion in the Oil & Gas Exploration and Production Industry.
• $3.4 billion annual loss due to steel corrosion in the Petroleum Refining Industry.
• $1.7 billion annual loss due to steel corrosion in the Chemical, Petrochemical and Pharmaceutical Industries.
• $6.0 billion annual loss due to steel corrosion in the Pulp and Paper Industry.

Corrosion is a real problem that costs the average American.

Industrial piping and vessels will corrode from excessive moisture or water penetration — if there’s not an effective, lasting treatment in place. Engineers mitigate these risks with protective treatments and inspections, some of which come with significant hurdles.

But there are more sustainable solutions that have been adopted to help engineers avoid (costly) mistakes and prevent corrosion under insulation and fireproofing entirely.

SIDE EFFECTS OF CORROSION UNDER INSULATION AND FIREPROOFING

Corrosion under insulation and fireproofing costs building and project owners billions of dollars every year. Many of the factors that cause corrosion, like equipment design, weather, salt spray, humidity and other factors are a challenge — if not impossible — to control. This makes consistent maintenance and frequent inspections not just necessary, but standard.

Corrosion under insulation and fireproofing are responsible for many leaks, cracks and other damage including catastrophic structural failure, and there’s pressure in the chemical, manufacturing and refining industries to find effective solutions.

Corrosion under insulation and fireproofing will continue to occur for the foreseeable future, making preventative maintenance and CUI/CUF detection methods of critical importance. Preventing corrosion under insulation and corrosion under fireproofing could save the industry from extra, unnecessary costs and energy expenditure.

Because fireproofing is a necessary part of any industrial productivity to protect workers and the public, measures must be taken to control CUF.

STRATEGIES FOR PREVENTING CORROSION

There are a few effective strategies for preventing corrosion under insulation and fireproofing, from the materials selected to the barriers and maintenance systems in place. Many times the means utilized to discover corrosion are not timely and elements must be replaced.

But there are a number of non-invasive methods for inspection, from Eddy Current, radiography to ultrasonic thickness measurements, where sound waves help to capture data from the piping design. This data helps engineers determine instances of CUI and CUF in structural elements, and piping and vessels so that the damage can be addressed.

Expedient discovery is an important part of the strategy. When corrosion begins, the damage is most times exponential with time.

MORE EFFECTIVE SOLUTIONS FOR CORROSION

However, there’s another approach to prevention: using a corrosion inhibitor. When applied, a high-quality corrosion inhibitor product provides excellent protection and damage resistance to structural elements, industrial piping and vessels.

Modern manufacturers have produced a cold fusion concrete that contains an alkali-activator largely comprised of glassy elements, resulting in a product that prevents damage like other materials can’t. The mixture contains no Portland cement, making it far more environmentally palatable to produce, and the product contains none of the inherent weaknesses of Portland.

Using an alkali-activated cement solution gives engineers more options for corrosion protection, as it’s easily produced by combining materials that are accessible throughout the world.

The inherent concrete corrosion inhibitor has been proven to prevent rusting and damage on metal substrates, even after being tested with ten thousand hours of salt spray exposure (ASTM B117). Third-party test report results indicate that using this glassy corrosion inhibitor has a higher resistance to acids, solvents, sulfates and fire than other treatments.

SOLUTIONS THAT SUSTAIN

Source: Corrosion under insulation and fireproofing has been a long-standing issue for engineers. “CUI is difficult to find because of the insulation cover that masks the corrosion problem until it is too late,” wrote Michael Twomey for Inspectioneering. “It is expensive to remove the insulation.” Fireproofing is no different.

But engineers and builders have solutions for corrosion under insulation and fireproofing by using the right forms of prevention. Maintenance and inspections are a standard part of every job site, but using an effective corrosion inhibitor is the best way to prevent damage and costly repairs.
The corrosion inhibitor materials from Aluminopolymer Solutions have helped engineers everywhere address the demands (and cost) of better structural element, piping and vessel protection. Aluminopolymer Solutions’ Cold Fusion Concrete/cement’s glassy characteristic electrically insulates the substrate and doesn’t allow water or chemicals to contact steel features, eliminating the possibility of corrosion before it begins.

Your project will likely require some sort of fireproofing to protect workers and reduce economic loss during explosions or fire events. Using an economical and environmentally superior fireproofing that inhibits corrosion at the same time makes perfect sense.

The vast majority of clients are return customers, and working with Aluminopolymer Solutions includes comprehensive training prior to using their products.

The best way to prevent damage is by inhibiting it completely. If you’d like to find out more about Aluminopolymer Solutions and the high-performance products available, reach out to an expert here.

Steel loses approximately 50% of its load-bearing capacity when it reaches 1,000oF (537oC). Accordingly, all structural steel buildings and industrial plants with human occupants must be protected from fire events to allow rescuers time to evacuate structures.

Fireproofing can be active, or passive. Active fireproofing consists mainly of sprinkler systems, gases or other means of automatically extinguishing the fire. Passive fire protection consists of sacrificial layers applied to the surface of steel elements in order to provide time for extinguishing the fire or evacuating occupants before structural collapse.

Fire protection is typically specified considering two potential events consisting of cellulose or hydrocarbon events. Cellulose consists of wood fires that develop heat slower and generally develop less overall temperatures. Cellulose fire protection is assessed using a gradual oven test temperature that achieves 2,000oF (1093oC) in four hours. Cellulose protection is utilized in schools, residential, hospitals and commercial structures.

Hydrocarbon consists of aggressive fuel and chemical fires that develop higher heat faster. Hydrocarbon fire protection is assessed using an expedient test oven high temperature of 2,000oF (1093oC) within five minutes and maintaining that temperature for the entire duration of the test.

Other fire exposure protection and testing can consist of Jet Fuel, Pool Fire, Blast and Hose Stream testing. It is, therefore, important for engineers to understand the fireproofing requirements they must meet and the structural steel fireproofing options available.

STRUCTURAL STEEL FIREPROOFING CODE REQUIREMENTS

Specific code requirements will vary based on your jurisdiction, although most are based on model codes such as the ICC/IBC, NFPA or NORSOk.

The rating of structural components or fireproofing systems is typically expressed as an hourly rating. For example, if a two-hour fire rating is required, the system or construction elements will need to meet the requirements for a two-hour rating in a standard ASTM E119/UL263 (cellulose) or UL1709 (hydrocarbon) fire-resistance test. Fire resistance directories can be used to determine the fire-resistance ratings of various building elements, such as in the directory provided by Underwriter’s Laboratories.

The requirements for any given construction project will vary based on a number of factors, including intended use, location and design. To establish the required fire resistance ratings for your project, consult your local building code, refer to model building codes and/or refer to structural/architectural design requirements.

STRUCTURAL STEEL FIREPROOFING METHODS

In order to meet passive structural steel fireproofing code requirements, there are a number of methods available.

SPRAY-APPLIED FIRE-RESISTIVE MATERIAL (SFRM)

The most common fireproofing method in the United States is to apply a spray-applied fire-resistive material (SFRM). Typical SFRMs are composed of cement and gypsum and may contain other materials such as mineral wool, quartz, perlite or vermiculite. The fireproofing is applied as either a wet or dry spray, or may also be trowelled on to the required thickness.

SFRMs are typically used when fireproofing steel beams or columns. While not its primary use, SFRMs may also provide an added benefit in the form of acoustical or thermal insulation.

However, SFRMs are not usually suitable for surfaces with high exposure to moisture or humidity, which can deteriorate the product. This can make it difficult to use in areas with high humidity or where there are freeze-thaw cycles. Most SFRMs provide little to no independent corrosion inhibition for steel elements and other relative protection must be provided. The surface preparation (blasting, primers, lath/attachments, etc.) for most SFRMs can be costly and time-consuming.

INTUMESCENT COATINGS

Intumescent fire-resistive material (IFRM) coatings are another fireproofing material for structural steel. A thin layer of an epoxy-based mixture is applied to the surface. When heated, this coating chars, foams and expands — up to 100 times its original thickness — creating a barrier between the steel element and the fire.

One of the benefits of intumescent paint is its lightweight characteristic and its corresponding ability to be used on exposed steel surfaces, without compromising design.

However, intumescent products are highly vulnerable to environmental exposure during the application, which can limit their performance. The cost of intumescent coatings is also much higher than other options, with the cost increasing the higher the fire rating required.

Intumescent products typically contain inherent corrosion inhibition for steel elements. The surface preparation (blasting, primers, lath/attachments, etc.) for most IFRMs can be costly and time-consuming.

RIGID BOARD FIREPROOFING

Rigid Board Fireproofing involves installing a rigid fire-resistive board to beams, columns and deckings. Rigid board fireproofing can be used in out-of-sequence construction phases so that it can be installed “as-you-go.” Rigid board fireproofing can also be used in many environments, including places with freezing weather conditions and with a variety of substrates.

However, rigid board fireproofing tends to be a more expensive and slow to install option, which can impact tight project budgets and timelines. Rigid board fireproofing provides no independent corrosion inhibition for steel elements and other relative protection must be provided (blasting, primers, galvanizing, corrosion-resistant paints, etc.).

FLEXIBLE BLANKET SYSTEMS

Flexible blanket systems offer combined fire, thermal and acoustic insulation and produce no toxic smoke at high temperatures. They are a lightweight and versatile product that can be easy to install even on complex shapes.

However, there is no customization available with flexible blanket systems — the product thickness is set by the manufacturer. The products also require additional fasteners as part of the installation. Finally, there are limited manufacturers of these products.

Flexible blanket systems provide no independent corrosion inhibition for steel elements and other relative protection must be provided (blasting, primers, galvanizing, corrosion-resistant paints, etc.).

PORTLAND CONCRETE

Concrete and masonry used to be one of the most common methods for fireproofing structural steel. These days, Portland concrete is mainly used to encase large areas of steel such as when fireproofing steel columns.

However, traditional concrete fireproofing of structural steel requires a larger volume of space, has a high carbon footprint and is not design-friendly. Portland concrete fireproofing provides little to no independent corrosion inhibition for steel elements and other relative protection must be provided (blasting, primers, galvanizing, corrosion-resistant paints, etc.).

ALUMINOPOLYMER FIREPROOFING METHODS

The traditional methods that have been long-used in the construction industry often have drawbacks and cannot be used to meet the design or fireproofing needs of projects across a wide range of environments and complexity.

That’s why Aluminopolymer created Corebond FR, a spray-on fireproofing for steel. The innovative engineering behind Aluminopolymer revives and reimagines ancient methods used by the Romans to create the next generation of SFRM.

Our aluminopolymer concrete technology is a high-density, Portland-free fireproofing material, and it is unlike any other commercially available product. Corebond FR can be applied to any size steel, overhead and vertical — and it’s never been easier to use spray-on fireproofing for steel beams, columns and systems.

Corebond FR, up to a 4.5-hour fire rating, can be applied in a single one-pass layer, saving you time and providing significant value for money compared to other products of a similar rating.

Corebond FR boasts a number of benefits, including:

• Withstands extreme heat without degradation
• Highly abrasion-resistant
• Highly impact-resistant
• Highly resistant to acids, solvents, chlorides and sulfates
• Able to withstand weathering and resistant to freeze-thaw cycling
• Long-life span (estimated up to 10 times that of traditional Portland cement concrete)
• No need to blast, prime or use mesh reinforcements or corner beads
• Installs extreme inherent corrosion inhibitors
• Already passed UL1709 5th Edition Requirements
• Exceeds many technical specifications

The superior strength and durability of Corebond FR make it highly recommended for applications where safety is paramount, such as petrochemical plants, power plants, schools, hospitals, and military and dock facilities.

By using 50-60% recycled materials, no volatile organic compounds and using no Portland cement in our manufacturing, Corebond FR is an eco-friendly product that can reduce your carbon footprint. This may be of great help with obtaining LEED certifications.

Corebond FR bypasses all the challenges of traditional fireproofing options, providing an easy-to-use, cost-efficient, environmentally-friendly and high-performing solution.

LEARN MORE

Make sure your project uses the best fireproofing on the market. To learn more about the difference between Corebond FR and traditional methods of steel fireproofing, contact us.