If you’ve searched for any type of passive fire protection or petroleum facility fireproofing lately, you likely found a good amount of information about fire-retardant intumescent coating systems, but very few sites actually answer three common questions:
- What are intumescent coatings and how do they work?
- What are the benefits and drawbacks of using intumescent systems?
- How do intumescent coatings compare to other fire protection options?
As with any fireproof system, intumescent coatings are designed to delay the failure point of steel equipment or structures during a rapid temperature rise, or UL 1709 rated, fire. Applied as a spray coating or a molded on epoxy coating, intumescent systems chemically react and expand when exposed to a fire and to create a carbon-based layer of char.
Design installation of an intumescent coating system differs slightly based on the type of system purchased. In petroleum and petrochemical applications, most coating systems involve shipping equipment to the vendor for measurement and design purposes. Vendors create fitted, epoxy coating molds, prepare equipment surfaces and then permanently apply the systems to equipment.
This installation method requires that either the purchasing contractor or destination plant pay freight costs for shipping equipment to and from the vendor location and can lead to significant periods of downtime or delayed construction time.
Equipment and Coating System Maintenance Issues
Most intumescent coating vendors cite permanence as a feature or benefit of their fire protection systems. Due to the potential hazards in the oil and gas industries, refinery equipment requires routine maintenance, especially on the critical process control equipment that fire protection systems protect. These permanent coating systems do not allow for easy removal in the event that maintenance is necessary.
According to Gregory Fehr, of the Nevada corrosion research group ATMG, exposure to weather, particularly water, can lead to cracking and delamination of coating systems. Unlike the simple process of repairing fire protection blankets, intumescent coating systems requires a much more detailed inspection and repair process, sometimes involving extended equipment downtime.
Corrosion, a leading concern in the oil and gas industry, is caused by the presence of water or another electrolyte that leaves salts on steel surfaces of pipes and equipment. An Exxon Mobil Chemical report cited corrosion under insulation as the highest cause of leaks in refining and chemical facilities. Inspecting for corrosion under coated fireproof insulation requires cutting small sections, or plugs, in insulation and completing ultrasonic testing. Upon discovery of corrosion under coated or molded-on fireproofing, the entire system must be removed and replaced with new coating after pipe or equipment is repaired. In contrast, blanket or jacket insulation systems only require removal for routine corrosion inspections or repairs.
Alternative Fireproofing Solutions
While intumescent coatings are ideal for protecting building structural steel, well-designed fire-resistant jacket offers a superior option for fireproofing process equipment in petroleum and chemical plants. UniTherm FirePro by UniTherm is a high-temperature insulation system that offers fireproofing for critical process equipment and addresses all of the common issues with molded-on coating systems.
Designing completely from detailed CAD drawings of equipment, we manufacture FirePro jackets without requiring equipment on site. This allows you to avoid any expenses associated with pre-installation treatments, equipment freight or downtime.
Constructed with a weatherproof exterior and a high-temperature, single-throw strapping system, FirePro systems are corrosion neutral, easy to remove and replace for routine maintenance. Compared to intumescent coating systems, or any other fireproofing product, FirePro has the lowest life-cycle cost for fireproofing critical process equipment.
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