Improvement of Methodology for Assessing Fire-Protective Efficiency of Intumescent Coatings Applied on Metal Constructions

Abstract

The article observes the possibility and feasibility of introducing new and improved methodology for assessing the performance of fire retardant intumescent coatings for steel structures. The results of a comparative assessment of coatings based on a set of parameters obtained in laboratory conditions are presented: swelling coefficient, adhesion coefficient, adhesion of the coating system under high temperature conditions, kinetic parameters of thermolysis, thermal insulation. The small-scale laboratory test was developed to evaluate thermal insulating ability of 4 intumescent coatings applied to small steel plates. An improvement of the control method for assessing the fire retardant efficiency of intumescent coatings is proposed instead of one test plate with dimensions of 600x600x5 mm with intumescent coating applied, a design of a metal frame-holder is proposed, in which 4 plates with dimensions of 300x300x5 mm can be fixed, and a set of thermocouples can be installed on each of them; all 4 plates are heated in the same conditions, thus the contradictions which may occur between the results of separate experiments are avoided. Such improvements made in the methodology of investigating the properties of intumescent coatings appeared to be fruitful, as correlation can be established between the laboratory tests and large-scale tests.