Problem Solving Forum
January 9 - January 13, 2017
Where would you use epoxy and cementitious intumescent coatings?
Selected Answers
From
Stephen Dobrosielski of Retired on
January 11, 2017:
Alfredo, good summary filled with a lot of common ...read more
Alfredo, good summary filled with a lot of common sense. The problem with common sense is that it is uncommon.
From
Alfredo Claussen of Instituto Mexicano del Petroleo on
January 10, 2017:
Independently of the material proposed for fire pr ...read more
Independently of the material proposed for fire protection, one must first address the requirements. In order to pretend to get a certain degree of protection, the type of fire and its characteristics need to be clearly established and throughly understood. In the severe conditions of the petroleum industry, the exact type of fire needs to be considered. Another often neglected consideration is that most of the accidents start with a leak, then an explosion, and finally a fire. If the material does not withstand the pressure wave of the explosion, a damaged "protection" will achieve little or nothing. Cementitious coatings seldom achieve the resilience to actually withstand a typical pressure blast wave from an explosion of hydrocarbons, therefore I'm skeptical about their applicability in structural steel applications, like refineries or offshore platforms. Even epox -based coatings need to be carefully evaluated in regards to their adhesion and integrity (reinforcement). The objective is to avoid disbondment and thus, failure to protect the underlying steel from overheating. Cementitious coatings, on the other side, seldom have the flexibility and toughness to remain adhered to the steel; the sad case of the asbestos-based coating used on the World Trade Center demonstrated the fragile, failure-prone nature of those types of materials. Very little material remained adhered to the steel beams after the initial impact. And finally, the coating needs to meet the required degree of corrosion protection, especially in corrosive atmospheres (most frequent in refining and offshore or coastal areas). To round the subject, a specialized consultant should be assigned to the design and construction, one who is trained and knowledgeable enough to fully understand the nuances inside the different standards used to define the fire, and then the complex response of the protective material. Few coating vendors really understand the erosive nature of a jet fire or the action of the blast wave, just for example!
Another "gray" area is the classification of these coatings, as sometimes they are called "fireproofing," which is an improper term; and in other cases the wording "active" vs "passive " coating is wrong, too An active fire protection is, by definition, a system that requires a deliberate and well defined action, like the starting of a firewater pump or the opening of a deluge valve. Thus, calling "active" a fire protection coating is not proper. Those should be properly called "passive," and the distinction then shall be between "intumescent" and "insulating," but both kinds are passive. After the tremendous explosions and fire on the Abkatun-A Permanent Offshore platform of PEMEX in Campeche Bay in 2015, the need to review and reevaluate the effectiveness of passive fire protection coatings was exposed. Their poor performance allowed the main structure to collapse early and contributed to the almost complete destruction of the platform.
From
Mika Mack of MAPPA INC. on
January 10, 2017:
(laughing)
I was hoping for less consensus and m ...read more
(laughing)
I was hoping for less consensus and more truth.
Although my background is more on the cementitious side, I love the articles and data supporting the epoxy intumescent coatings.
From
Joe Miller of NextGen Green Building Products, Inc. dba Direct2Contractors.com on
January 10, 2017:
Intumescent fireproofing is typically made from ep ...read more
Intumescent fireproofing is typically made from epoxies or other resins, not cements.
Cement-based fireproofing is passive in my experience. It does not expand when heated in a fire like intumescent fireproofing does.
From
Michael Quaranta of OPERATIONS 40 on
January 9, 2017:
Ahhh Mike Mack . . . the truth is in the reading! ...read more
Ahhh Mike Mack . . . the truth is in the reading! The typical solvent-based epoxy is flammable both in the can and on the applied surface. So your words reporting active (?) and passive (?) fireproofing, plus the time window to escape (!!!) are perfect, followed by the question:
What true fire rating should be applied to solvent-based epoxy intumescent coating, or do we need more physics coating truth and less consensus in the rated ASTM specification?
From
Mika Mack of MAPPA INC. on
January 9, 2017:
Epoxy and cementitious intumescent coatings are us ...read more
Epoxy and cementitious intumescent coatings are used for active and passive fireproofing.
One is designed for suppression and the other for a time window to escape a burning structure.
Uses depending on substrates and exposure.
From
Clyde Morgan of BURNS & McDONNELL on
January 9, 2017:
Use epoxy intumescents on refinery structural stee ...read more
Use epoxy intumescents on refinery structural steel, refinery supporting skirts, refinery vessel supporting saddles, surface protection for propulsion.