1) If pitting or black spots appear on the working surface of the gear, if the spot distribution area does not exceed 30% of the tooth surface, it can continue to be used.
2) When the driving gear and the driven gear have severe fatigue pitting and local spalling, if the damaged part does not exceed 1/3 of the tooth height, 1/10 of the tooth length, and the number of damaged teeth: the driving gear does not exceed 2 (and no Adjacent), there are no more than 4 driven gears, and if there are no more than 2 adjacent teeth, the damaged area can be ground and used again. If the above requirements are exceeded, new parts shall be replaced in pairs.
3) If the thread damage of the drive gear shaft end does not exceed 2 teeth, it can be used continuously. If it exceeds 2 teeth, the thread needs to be welded and reprocessed, or the thread diameter is reduced by one level, and a nut is used.
4) When the wear of the driving gear shaft bearing journal exceeds 0.04mm, the journal can be repaired by brush plating.
5) When the spline wear on the front end of the driving gear shaft exceeds 0.20mm, a new flange can be used to reduce the gap, or rework after surfacing.
6) The surface of the driving and driven gears are worn out. When the tooth thickness exceeds 0.40mm, new gears need to be replaced.
7) When individual teeth are partially broken and not adjacent, it is allowed to re-grind and reuse after surfacing.
8) When the flanges of the driven gear and the driven gear shaft or the fastening bolt holes of the differential case are worn out due to looseness, the bolt holes can be reamed and reamed, with enlarged special bolts; such as loose rivets And when the holes are worn out, the holes need to be reamed with rivets one by one and re-rivet.