During operation, the working parts (hammers) of hammertype feed-crushing machines are subjected to intense wear. The maximum wear of the working edge of the hammer is considered to be wear up to the main axis of symmetry. To reduce wear and increase the service life of the hammer, a technology of combined hardening of the working edge of the hammer with a hard alloy plate using iron-carbon solder is proposed. This work is based on theoretical substantiations and experimental processing of production tests of hardened hammers. (Research purpose) The research purpose is searching for the regularities of the wear process of hardened hammers from operating time during the operation of the feed crushing machine. (Materials and methods) The design and technological parameters and mechanical properties of the materials of the hardened hammer were substantiated. Methods of processing the results of production tests based on mathematical statistics and reliability theory, comparative methods of analysis of hardened and serial hammers were presented. (Results and discussion) The results of studies of experimental hardened hammers were presented, in which the mechanical strength and the magnitude of the diffusion zone of the soldered connection of a hard alloy with the material of the hammer and the iron-carbon solder used in this case were determined. We carried out a theoretical analysis of the dependence of hammer wear on operating time and constructed a mathematical model for predicting the life of a hardened hammer. It was determined as a result of theoretical studies that with the combined hardening of the working edge of the hammer of the feed-crushing machine with a hard alloy VK8 using iron-carbon solder, the maximum operating time increases by 2.76 times. (Conclusions) The results of theoretical studies and production tests prove that the resource of hardened hammers has increased 3.5 times compared to serial ones. The constructed mathematical model for predicting the life of hardened hammers accurately reflects the results of experimental values of the dependence of hammer wear on operating time.
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