Study on Limiting Load for Scuffing and Specific Wear of Spur Gears : Effects of Lubricating Oil and Tooth Form

Abstract

Limiting load for scuffing using spur gears, which were case-hardened and ground, was investigated. The load was stepped up according to the provided load stage in our experiments to the load stage of scuffing failure. Before and after the running of test gears, the wear of test gears was measured with a balance. At first the running time of test gears at each load stage varied very widely and we found that, the running time at each load stage has no influence on the limiting load for scuffing. For our experiments four kinds of base oil viscosity were used. As antiscuffing additives ZDTP and EP additives at various concentrations were used. Influences of lubricating oil viscosity and concentration of ZDTP and EP additive on limiting load for scuffing and specific wear were investigated and the results summarized. Furthermore the integral temperature of tooth surface according to the ISO proposal was illustrated and discussed.