Precautions for Using Bolts

Precautions for using bolts

1. Need to check large-angle and high-strength bolts. For general surveys of high-strength bolts to prevent leakage, small hammer percussions must be used. This method is mainly to clamp one side of the nut with your fingers. If you feel a slight tremor in your fingers, try to get as close as possible to the nut near the washer, and then hit the other side of the nut with a hammer. If the finger feels a slight vibration, it is considered qualified. If the vibration is large, it may be missed or not tightened. If there is no vibration at all, it is over tightening.

2. Quality control and acceptance of torsion shear high-strength bolt connection. Due to the structural characteristics of the plum blossom, during the construction process, the dry part of the plum blossom bears the anti-torque, so the plum blossom head is partially twisted. In other words, the same torque is applied to the bolt connection pair. Therefore, during inspection, only need to visually check whether the plum blossom head is damaged and qualified. However, special wrenches cannot be used for bolts of individual parts, so the inspection method for high-strength large hexagon bolts of the same diameter must be followed.

3. If high-strength bolts must be tightened with a torque wrench due to structural reasons, an approved torque wrench should be used, and the angle method should be used for spot checks. After the torsion shear type high-strength bolt connection is finally tightened, the number of bolts without torx heads should not be greater than the number of bolts at the nodes, and special wrenches cannot be used for final tightening. The installation inspection must be completed 1 hour after the final tightening, but must be completed 24 hours before.