The report highlights some features of the methods and results of laboratory and field tests of the USSR newly developed ice-resistant enamel EC-437 and foreign-made enamel INERTA-160 universally recognized as one of the top-quality enamels. In terms of corrosion-resistance and friction properties, enamel EC-437 was found to be a par with INERTA-160 in abrasion resistance, with ice adhesion being much lower for EC-437.
The present paper addresses the problem dealing with the choice of ice-resistant enamels best suited for underwater surfaces of ice-breakers, ice vessels and offshore structures. In the USSR, researches covering such problems are undertaken for the first time. To achieve the goal in view, comparative laboratory tests on a vast amount of samples of home- and foreign-made enamels have been carried out. From the results obtained, enamels EC-437 (composed of epoxy resin, modifier and amine-type hardener) and INERTA160 have been field to be the most optimal from the viewpoint of their adhesion and friction properties, corrosion and abrasion resistance. The former is developed by the Leningrad Research and Production Enterprise "PIGMENT", the latter is manufactured by the Finland Company "TEKNOS MAALIT".
Determination of the adhesion force between enamel and ice is shown schematically in Fig. 1. Directly in the experiments, force Ra required to tear off an enamel sample from ice was measured. One can see from Table 2 that friction factors for EC-437 and INERTA-100 are the same within the range of calculation accuracy. The effect of the movement velocity on the friction factor is similar to that observed by Edwards(1980). Moreover, as the results have shown, the friction factor at a constant movement velocity and varying pressures is practically independent of the pressure acting on an enamel in the range of б = (0.025 - 1) MPa.