Durability of cutter assemblies and its causative factors

Abstract

Cutter assemblies operate under stressful conditions: the knives are subjected to high dynamic loads, the cutter shaft rotates at a frequency of 5–100 s-1, the electric driving motor of the cutter shaft overcomes high starting moments, the bed is subjected to significant static and dynamic loads, the food raw materials and humid atmospheric air in the production room is corrosive to the structural elements, etc. Under the influence of these factors, the cutter assemblies break down, which causes unregulated pauses in food raw materials processing and also requires high expenses for equipment repair. The aim of the paper was to study the durability of the main cutter assemblies and to establish its main determining factors. The presented numerical values of durability of cutter assemblies have been obtained as a result of the planned, warranty and post-warranty practical maintenance of cutters by the engineering team of GEA FOOD SOLUTIONS UKRAINE, LLC, the mechanical supervisor staff of Cherkassk Food Company, LLC and also as a result of scientific research of the processes that provide the operation of these machines and that were carried out at the Cherkassy State Technological University (the Ukraine). The components that operate under the most stressful conditions are knives, a cutter shaft and its bearing assemblies, and the electric driving motor of the cutter shaft. At the same time, the durability of most cutter assemblies is limited by the quality of operation of the cutter head and the durability of the knives. The expenses for the repair or replacement of cutter assemblies can amount to tens of thousands of euros (not including the losses caused by equipment downtime). By applying the appropriate technical solutions and cutter system operating rules, it is possible to significantly improve the durability of a cutter and reduce these expenses.