Comparison analysis and parameter study for roll separation force to avoid bearing failure in tube mills

Abstract

This paper reports the reaction force acting on the various rollers of roll forming tube mills. The roll separation force is the major criteria for designing of tube mill structures as well as bearing selection for tube mills. Cold condition tube pass in squeeze roll produces high roll separation force causing Bearing failure in tube mills. The frequent failure of bearings due to over load in squeeze roll is important issue in tube manufacturing industries in this current era. we studied the roll separation force by FEM simulation with three different materials with different strength includes High Strength Low Alloy Steel (yield strength of 750MPa and ultimate strength of 900MPa), St 52 (DIN 17135 Standard, yield strength of 400MPa and Ultimate strength of 500 MPa) and SAE 1010 (yield strength of 350MPa and ultimate strength of 550MPa). The piecewise linear plasticity material is selected in LS-Dyna material database for this simulation. The comparison study states that the increase in strength increases roll separation force. Increase in load is observed with decrease in D/T (diameter to thickness ratio).