Fracture cause analysis of the extruder’s shaft and geometry optimization of the spline

Abstract

The article is devoted to increasing of the durability of technological equipment elements, forecasting of the resource and diagnostics of failures of the technical system. The basic regularities are analyzed and causes of the failure of the extruder’s working body shaft are determined. For torque values M = 40.74 - 64.37 N·m and of the extruder’s working body shaft, the stress-strain state of the contact surfaces of the keyhole of the extruder’s shaft is calculated by the method of three-dimensional finite element modelling. The maximum values of the stress intensity σint(max), which arise on the edge of the key groove, are calculated. It was established that an increase in the distance of the key groove to the fillet of the working body shaft by 2.0 mm leads to a decrease in the maximum stresses on the edge of the key groove by 15.72%. The results of the research allow optimizing the geometry of the shaft.