Composite Deposits Developed by Welding on Horizontal Mill Hammers

The paper presents the concept of designing active hammer edges of horizontal mills for grinding tungsten carbide waste by making composite layers deposited by welding. The new generation of hammers is carried out on the principles of preventive and repetitive maintenance, by endowment with wear addition, predetermined as volume and geometric configuration, depending on the specific conditions of uninterrupted use for a period of time established for economic reasons. The main demands that affect the integrity of the active areas of grinding mills (high pressure abrasion wear, thermo-mechanical fatigue) generate both material losses and output from working rates, as well as excessive elongation of the support elements under the combined action of centripetal force and of the pressure exerted by the ground load. Under these conditions, the technically and economically optimized solution is to design the modular active elements in the form of easily assembled detachable components, made of a low alloy steel with average tear resistance (450-600MPa) on which we deposit by welding layers of composite austenitic steel, hardened by compression, so as to increase the lifetime of the hammers by up to 35% compared to the present solution, which can be upgraded up to 3 times for reuse.