Hybrid Tribotest Method for Realistically Measuring Friction and Wear of Heavy-load Bearing Shells

Bearing shells are widely used in heavy-load friction pairs of high-end machines to reduce wear, thereby extending the lifetime of machines. Tribotests are necessary for bearing shells to evaluate their wear behaviors, reliability, and durability. Existing tribotests of bearing shells can mainly be categorized into two types: full-scale machine tests or local-scale standardized tests (pin-on-disk, etc.). The former has more realistic test configurations but is time/labor-consuming and expensive. Contrarily, the local-scale standardized tests are simple, low-cost, and flexible to use, but their oversimplified contact configurations make the measuring results in poor correlation with practical applications, easily misleading the screen of bearing shells. For that, this study develops a hybrid tribotest method and corresponding instrument (tribometer) to realistically measure the friction and wear of heavy-load bearing shells, which combines the advantages of the facticity of full-scale machine tests with the simplicity and inexpensive of local-scale standardized tests. In this method, a convenient round-arched concave on the bearing shell holder is designed to achieve the conformal contact friction of the bearing shells, of which the size can also be modifiable and compatible with different bearing shells. In order to reproduce the actual friction conditions in the machine, an easy-to-removal roller counterpart with an adjustable speed down to 0.5 rpm and a hydraulic loading with a controllable force exceeding 93 kN (equivalent to 9.3 tons) are employed to achieve the low speed and heavy load. Based on the method, both alloy and polymer bearing shells are measured. The measuring results indicate the feasibility of the hybrid measurement method and tribometer. The proposed method offers a facile and actual way for screening structural/material, the wear mechanism analysis, and the contact configuration investigation of bearing shells.