1. Check the surface of the steel pliers is smooth, smooth, there is no cracks, cracks, etc. and the welding there is no obvious signs and deformation.
2. Ring, shaft hole with no cracks, wear the diameter can not exceed 10% of the original diameter.
3. The factory also need to carry out the official relocation of the load of 2 times the test, after the test there is no deformation.
4. The clamp of the plate clamp shall be marked with a safety load.