Increasing the reliability of refrigerators used to produce green paste

Abstract

The work is aimed at the oxidative processes occurring in the metallic structures of the universal refrigerators “UKHB 3/30” used to transport and cool calcined coke. The temperature of the coke entering the device reaches 1320 oC. As it moves along the device, chemical and thermal effects occur on unprotected metallic structures with the formation of erosion centers and through damage to the shells. The service life of refrigerators hot-cut metallic structures made of A284 Grade B (ASTM) is 1 year, which determines its repairs frequency. Experiments on the oxidative processes in real conditions of operation of refrigerators were conducted for samples made of carbon steel of the A284 Grade B (ASTM) brand and heat-resistant high-alloy steel AISI 301. Changes in the chemical composition and physical parameters were determined in the samples. The thermogravimetric method for estimating the corrosion kinetics based on the sample mass loss, spectrometric study of metal samples, and classical chemical “wet” analysis were used. According to the results, the degree of corrosion damage of samples after 1,5 hours is estimated. The kinetics of corrosion has been studied. The mechanism of decarburization of the surface layer in A284 Grade B (ASTM) steel and the accompanying deterioration of the metal mechanical properties are described. An economic analysis of the feasibility of using AISI 301 steel to increase the service life of refrigerators was carried out.