REENGINEERING OF TECHNOLOGY FOR PRODUCING CASTINGS FROM HIGH-CHROMIUM CAST IRON ChKh28

10.25712/ASTU.1811-1416.2023.03.015

Abstract

One of the most important tasks of the mining, ore and timber processing industries is import substitution and reengineering of foreign equipment parts. In this paper, using the principles of reengineering, we study the chemical composition and structure of a used part of crushing equipment. It has been established that the presented samples were smelted from high-chromium cast iron ChKh28, additionally alloyed with molybdenum, vanadium and nickel. Its closest foreign counterpart may be steel grade DIN 1695-81: G-260Cr27. The results of the study showed that the casting material was heated to hardening temperatures up to 950-1050 °C and held at these temperatures for at least 2 hours, followed by cooling in air to temperatures of 160-200 °C and tempering at a temperature of 200 °C for at least 2 hours, which is confirmed by the hardness of the samples at the level of 53-64 HRC and the high degree of equilibrium of their structural-phase state and phase homogeneity.