Impact of Surface Grinding on the Performance of Tilting Pad Bearings

Tilting pad bearings are core components of rotating machinery. Due to factors such as manufacturing, installation and operation, there may be a mismatch between the bearing pad surface and the shaft diameter, leading to issues like high bearing temperature and rotor system vibration. In engineering practice, surface grinding is often used to resolve these problems. This paper analyzed the mechanism of surface grinding, systematically studies the impact of individual or combined surface grinding on the static and dynamic characteristics of tilting pad bearings and summarizes reasonable pre-load adjustment schemes. The results show that the principle of pad surface grinding is to change the pre-load coefficient of the bearings. The grinding of the oil inlet and outlet sides of the pad surface changes the clearance of the pad, increases the pre-load coefficient, reduces the working temperature of the bearing, increases the thickness of the oil film, and increases power consumption; the grinding of the middle parting surface of the pad changes the clearance of the bearing, increases the pre-load coefficient, and increases the main stiffness and damping coefficient of the bearing. Using these results, a fault diagnosis was performed on a turbine unit with excessive vibration during an on-site operation, leading to effective control. The research provides technical references for the condition monitoring of turbine tilting pad bearing vibrations and the safe operation of units, offering significant engineering implications.