Seeking advice on friction at the centrifugal pump shaft end and bearing housing cover
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This post was last edited by yxmqh on 2010-3-10 at 12:18. There was a centrifugal pump that was working normally until suddenly the temperature of the rear bearing housing rose to around 80 degrees Celsius. After replacing the bearings, friction occurred between the shaft end and the end cover of the rear bearing housing, causing the end cover to turn red from friction. The front and rear bearing housings were then disassembled, and the appropriate clearance and compression values were determined again; yet friction between the shaft end and the rear bearing housing end cover persisted even after reassembly. Finally, as there was no other solution, a gasket was added to the end cover of the bearing housing, and the \"friction\" phenomenon disappeared. I would like to ask everyone what the root cause of the friction between the shaft head and the end cover of the rear bearing housing is
No pictures, no truth.:lol Is the bearing clearance adjustment axial or radial? The bearing is in operation, generating heat and expanding; there is no clearance, and friction is present. How is the overall performance of the pump? What is the structural support for a centrifugal pump?
It seems to be a multi-stage pump, supported at both ends. Reason: Shaft play. Adjust the balance disc clearance.
First, the shaft has shifted; it is necessary to check whether the clearance of the balance disc (or balance drum) is within the specified range Is the balance tube blocked? Is the bearing pressure cap loose?
Detailed images are needed for analysis; please provide the image details, OP!
As you said, it’s likely that the gap between the bearing housing end cover and the rotor is too small; increasing the shims to widen that gap will solve the problem.
The issue of worn shaft end caps had not occurred before; it only started appearing after the bearings were replaced, indicating a problem with the assembly. When assembling bearing components, it is necessary to measure the clearance. and make adjustments. There should be a gap of 0.15~0.3 between the gland and the bearing; there is a formula for calculating this value, which is based on the distance between the centers of the bearings, the linear expansion coefficient of the shaft, and the difference between the temperature of the bearings and the ambient temperature. Additionally, the bearing must be heated before being installed on the shaft; otherwise, wear of the cover may occur.
It should be the clearance between the gland and the outer ring of the bearing; it’s a thermal expansion clearance, ranging from 0.08 to 0.15 mm