Influence of Installation Deviation of Thrust Bearing on Oil Film Flow of 1000 MW Hydraulic Turbine Unit

Abstract

The thrust bearing, as the only part bearing the axial load, is extremely important in vertical hydroelectric generating units. Its working condition directly affects the safe and reliable operation of the hydroelectric generating unit. However, during operation, the oil film is easily damaged under the influence of complex factors. Installation deviation is a key point that can cause temperature and pressure changes in the oil film, affecting the force on the bearing. This article takes the thrust bearing model of the 1000 MW Francis turbine unit of the Baihetan Power Station as the research object. Based on the fluid–solid coupling theory and CFD technology, the oil film characteristics of thrust bearings are analyzed, and the influence of inclination angles and installation deviation on the oil film flow performance of thrust bearings is discussed. The results show that as the inclination angle changes from 0.0030° to 0.0048°, the axial force changes from 856 t to 368 t, and there is an approximate linear correlation between them. The radial installation deviation has an effect on the axial force. Under the optimal working condition of an inclination angle of 0.0039°, when the radial deviation of the pad changes from 0 mm to 1 mm, the axial force changes from 1573 t to 1275 t. In the process of unit installation, it is necessary to pay attention to the installation deviation of the pad. The results provide guidance for the installation of the bearing, which helps to ensure the safe and stable operation of the station.

Keywords

• Francis turbine
• thrust bearing
• installation deviation
• oil film