Sliding friction and wear properties of friction linings with friction-promoting grease applied

The rheological properties of a commercial friction-promoting grease (FPG) were investigated using a cone and plane rheometer. Two friction tests were conducted at a low sliding rate (1 mm/s) using a wire rope (designed for mining use) and a commercial friction lining material. One involved dry-friction and the other greased conditions. The corresponding coefficient of friction (COF) in each case was determined and used to evaluate the effect of application of the FPG on the lifting performance of a hoist under normal conditions. In addition, experiments involving high-speed sliding friction between the wire rope and the friction material were also performed (with and without the FPG). Different sliding speeds and applied loads were used. The aim was to obtain the tribological behavior of the friction material in conditions that simulate a severe working environment for the hoist. The experimental results were analyzed and combined with the rheological properties of the FPG. The FPG can substantially protect the friction lining from wear and simultaneously provide an adequate COF (about 0.356) between the friction pair under normal working conditions. When the working conditions are severe, an increase in sliding speed causes a decrease in the COF. However, a larger load does not necessarily result in a smaller COF. Increasing the sliding speed or the load both aggravate the wear of the friction lining.