First, the sleeve
1) The sleeve diameter exceeds the maximum value of the gear pump bearing rules, that is, the shaft diameter plus the maximum allowable clearance of the bearing;
2) The outer diameter of the sleeve is smaller than the minimum value of the rule of the steel sleeve bearing, and the method of using the knurled sliding oil-free sleeve SF-1 can not ensure the quality requirement;
3) bushing attack or burning axle.
Second, the open bearings
1) severe wear of bearing alloy, the thickness of thinning more than 1/2;
2) bearing alloy layer shelling, harsh cracking, an area of 1/3 or more;
3) bearing alloy layer severe burning;
4) bearing alloy contact angle with the shaft is greater than 120o, can no longer use the shovel wiper plane approach to adjust the contact angle or side of the gap can not be adjusted too large.
Third, thin-walled tiles
1) bearing alloy layer of melting;
2) bearing alloy layer of severe wear, seizures bite, can not be tightened with pad method;
3) bearing alloy layer shelling or cracking;
4) bearing alloy layer wear is not severe, but can not ensure that the maintenance of the distance from time;
5) bearing alloy layer wear, need to use pad method to tighten the bearing, but the gasket thickness exceeds 0.5mm.
Fourth, thrust bearings
1) severe thrust pad wear, the thickness of thinning more than 1/2;
2) when the thrust pad burning;
3) thrust tile shelling, cracking.
