pay attention! !
1) Do not hit the bearing surface directly with a hammer during installation
2) Do not use insulating bearings with defective surfaces
3) Clean the bearing chamber and bearings, and do not adhere to conductors
4) Select a suitable shoulder to avoid current flowing through the bearing from the side of the bearing
5) The angle of 0.5MM depth and slope of 10-15° needs to be reduced on the bearing chamber
6) For DC motors, the shaft needs to be grounded during the resistance test
