Hex Bolt Manufacturers introduces three ways to tighten high-strength bolts:

1. Torque method
According to the closed system in which the torque M is proportional to the pre-tension, first, use a general wrench to tighten the nut starter, and then use a wrench with a visible torque value to tighten to the determined torque value.

2. Angle method
According to the close contact between the layers, the conversion angle of the high-strength bolt is directly proportional to the pretension of the bolt. When tightening, first use a short wrench to screw the nut to the untransformed position, and then use a long wrench to screw the nut to the determined position to reach the pre-tension.

3. Unscrew the tail of the bolt
For torsion shear-type high-strength bolts, this bolt has a special tail. When tightening, use a spanner to cover the bolt and the tail of the bolt, one sleeve rotates forward, and the other sleeve rotates. When the nut is tightened to a certain level, the end of the bolt is broken. Because the depth of the notch at the end of the bolt is determined by the closed relationship between the twisting torque and the pre-tightening force, the corresponding pre-tension value is reached when it is twisted off.