Wear-in behaviour of polycrystalline diamond thrust bearings

• Published in: Wear 2011-07, Vol.271 (9), p.2106-2110
• Main Authors: Knuteson, C.W., Sexton, T.N., Cooley, C.H.
• Format: Article
• Language: English
• Subjects: Applied sciences; Bearings; Bearings, bushings, rolling bearings; Coefficient of friction; Drives; Exact sciences and technology; Fluid-film; Friction, wear, lubrication; Hydrodynamic; Laboratory tests; Lubrication; Machine components; Mechanical engineering. Machine design; PCD; Polycrystalline diamond; Thrust bearings; Wear; Wear-in
• ISSN: 0043-1648; 1873-2577
• DOI: 10.1016/j.wear.2010.12.059

Polycrystalline diamond (PCD) bearings are designed for use in harsh environments, including process-fluid-lubricated applications such as those in oil and gas drilling turbines. This paper discusses the wear-in behaviour of polycrystalline diamond thrust bearings. Laboratory test results are presented that show the roughness, profile, and coefficient of friction of the polycrystalline diamond wear pads as the wear-in of the polycrystalline diamond bearings progresses. Laboratory test results show a significant decrease in the surface roughness and a change in the profile of the wear pads. Measured values of the coefficients of friction reveal that the lubrication regime of PCD thrust bearings can move from boundary to mixed-mode and may even become hydrodynamic after wearing-in for a period of time under the right conditions. This mechanism can provide extended life for PCD thrust bearings in harsh environments.