Повышение срока эксплуатации литых броней из высокомарганцевой стали мельницы полусамоизмельчения

Abstract

At the processing plants of the mining industry, a significant part of the total processing costs (from 45 to 65%) is spent on crushing and grinding operations, including mill lining. The efficiency of grinding equipment in the conditions of abrasive impact of ore and a continuous operation requires periodic replacement of a worn-out lining. The costs for its purchase, delivery and installation during a year amount to tens of millions of rubles, and the equipment downtime associated with the replacement of the lining reduces the volume of finished products by hundreds of millions of rubles per year. The practical efficiency of imported mill liners is not always confirmed by the expected positive result of their actual operation, and an increase in the equipment utilization coefficient (EUC), but their use definitely requires significant financial costs and entails risks in an unstable political and financial situation. Therefore, the task of increasing the service life of the mill liners is urgent. The paper presents a suggested and implemented solution to increase the lifetime of 110G13L steel lining for the wet semi-autogenous grinding mill (SAG mill-70х23). It includes monitoring of the actual liner operation and a mathematical simulation of the ore and ball trajectory in the mill, reveals zones of intensive wear, defects of liner castings and developed new structures of the lining elements. Applying the simulation software package, the authors studied the existing casting technologies, found reasons for defects and developed the casting technology for a new design of liners excluding defects. The paper contains industrial tests of the liners of a new design manufactured according to the developed technologies.