Maintenance techniques for radial and thrust bearings of turbine compressors

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This post was last edited by zhangya*ong on 2016-7-3 11:15. I. Precautions for the maintenance of radial bearings 1) It is generally not recommended to scrape the tilting pad bearings, but in order to ensure good contact throughout the bearing, slight scraping can be carried out provided that the thickness of the pads remains within acceptable limits and the surface quality of the babbitt meets the required standards. 2) When replacing the tile together with this housing, use red lead to check the contact between the newly installed lower tile housing and the lower bearing seat; the new tile housing must not be loose within the bearing seat’s groove, the gap on either side should not exceed 0.03 mm, and the anti-rotation pin must not protrude above the mid-plane of the bearing seat. 3) The position and direction of the tiles must not be reversed. When replacing an individual tile, ensure that its thickness does not deviate from that of the tiles in the same group. II. Precautions for the maintenance of thrust bearings 1) The clearance of the thrust bearing should be adjusted using shims on the non-working side, with no more than 1 shim being used. Adjusting the thrust clearance should be carried out after adjusting the rotor’s axial position by securing the cylinder. To measure the clearance of the thrust bearing, the cover on the bearing housing should be installed, and the bolts and pins along the midplane should be tightened before taking the measurement. The axial clearance of Mitchell-type thrust bearings is adjusted by the thickness of the end cover shims. 2) For Mitchell-type thrust bearings, when heating the thrust disc with a flame, care should be taken to prevent the surface of the thrust disc from being annealed. At the same time, the rotor should be placed at the outer dead center to prevent the babbitt in the inner bearing shells from melting. 3) During disassembly and assembly, alignment marks should be made to ensure the correct relative position of the thrust bearing pads; they must not be misaligned. 4) To prevent overload of the thrust bearing, it is essential to ensure that the end face runout of the thrust disc does not exceed the specified limits, and that there are no cracks in the joint surface of the bearing housing. 5) The operating position of the rotor should be adjusted on the working side of the thrust bearing; depending on the structure of the bearing housing, the thickness of the housing shims or the thickness of the shims on the working side of the thrust bearing should be adjusted. 6) The zero position of the shaft displacement probe should match the designed zero position, and the displacement indicated by the gauge should correspond to the shaft position variation indicated by the dial indicator.