Centrally Pivoted Tilting Pad Thrust Bearing with Carbon-Based Coated Collar-Experimental Results of Low- and Medium-Speed Operation

Experimental results of the research on a tilting pad thrust bearing with symmetrical pad support in the conditions of high loads and low speeds are presented in the paper. As described in the literature review, experimental results of tilting pad bearings at low speed/high load regime and transient conditions are rare. Unusual material selection - steel pad against a DLC-type coating on the collar was utilized. Such material combination has been mostly used in automotive industry in concentrated contact friction pairs, but it is not commonly used in thick film contacts. The tests included low speed high load and a test, where a Stribeck curve was reproduced. The steel pads showed minimum traces of contact and no visible wear was noticed on the collar coating. Differences of operation in medium and low speed were observed. Big variations of bearing temperature at medium speed and almost constant pad temperature at low speed were measured. At a specific load of 5 MPa transition to mixed friction was occurring at a sliding speed of approx. 0.18 m/s.