【 Weak current College 】 practical knowledge: overhaul centrifugal pump bearing technology standards---Power By 【 China power house network 】

First, rolling bearings
1, bearing and shaft with hole with the base system, bearing and shell of adopt-axis system.

Bearing size tolerances and running accuracy of the values in GB307-84.

2, and the bearing with shaft neck and housing bore by GB1031-83, journal roughness Ra value is less than 1.6 μ m, bearing inside roughness Ra value is less than 2.5 μ m.

3. use GCr15 and ZGCr15 steel manufacturing bearing rings and the roller, its rings and the roller hardness value should be 61 ~ 65HRC; GCr15SiMn and ZGCr15SiMn steel manufacturing, its hardness value should be 60 ~ 64HRC. Hardness inspection methods and the same part of the hardness of the uniformity requirement by JB1255.

4. check the bearing radial internal clearance and axial internal clearance should be consistent with the provisions of the GB4604-84.

5, rolling bearing inner and outer ring raceways should not wear, spalling, severe inner and outer rings shall have no crack; ball should wear, cage without serious deformation, no abnormal noise rotation and vibration, the stop should be gradually came to a halt.

6, for c-level tolerances for tapered roller bearings, roller and the Raceway contact precision, the role of a certain load, check for coloring, contact mark should be continuous, contact length should be not less than 80 roller bus.

2. sliding bearing

1, for radial thick wall tile

① use pressure PB method, lift axle method or other method of measuring bearing clearance and Watts case of interference, axis gap compliant, WA shell interference should be 0 ~ 0.02mm.

② check all parts should be no injury and crack, Bush should no flaking, stoma, crack, grooved and partial mill burns.

③ bearing and axle journal contact status check with coloring method, check the angle should be no 60 ° ~ 90 ° (1000r/min speed higher than the lower limit, speed is lower than by 1000r/min which limit). In the contact range requirements contact uniform, per square centimeter should have 2 to 4 touch points, poor contact, you must be lapping.

④ sweeping housing, the oil hole, no crack, leakage.

⑤ WA backs and housings should close even slightly with coloring method checks that the contact area of not less than 50.

2, for radial wall tile

① bearing alloy layer and Watts case closely should be firmly, without hierarchies, shelling. Alloy layer surface and two Watts of siding should be smooth, flat, not answer for any cracks, pores, skin, slag and defects such as scratches.

② WA backs and bearing bore surface should be closely aligned with the uniform, coloring method checks that the inner diameter less than 180mm, its contact area not less than 85, inner diameter greater than or equal to 180mm, its contact area not less than 70.

③ bearing and axle journal in the clearance and exposure status is guaranteed by the precision machining, its contact area generally do not promise, to lapping along the axial uneven exposure may be slightly trimmed.

④ assembled at the siding Department used the feeler gauge check 0.02mm should be can't squeeze is qualified.

3, for thrust bearings

① bearing should not wear, deformation, cracks, scratches, delamination, rolling and burn defects; and thrust up contact imprint contact area should be uniform, should be not less than 70 and the whole circumference of the tile, uniformly distributed; the same set of tile thickness difference should not be greater than 0.01mm, tile, babbit should follow the direction of rotation rounding into oil wedge for lubricating oil into the back of the load-bearing surface; smooth.

② adjustment gasket should be smooth, flat, not Flex, with thickness difference of not more than one layer gasket 0.01mm.

③ the bearing cap Assembly after repeated use push shaft measurement thrust bearing clearance, its value should be in the request scope. Use this method to measure and use axis displacement transducer side of thrust bearing clearance must be consistent and in accordance with the regulations to adjust probe indicates zero displacement.

④ bearings shell level of joint surface pretty tight,. Measuring the temperature of the oil hole and tile eye alignment, not skewed. Oil hole clean and smooth.