Construction precautions for steel structure bolts

The construction of steel structural bolts must be initially tightened before final tightening. The initial tightening of steel structural bolts requires the use of impact type electric wrenches or torque adjustable electric wrenches; And there are strict requirements for final tightening of steel structural bolts. Final tightening of torsion shear type steel structural bolts must use torsion shear type electric wrenches, and final tightening of torque type steel structural bolts must use torque type electric wrenches The large hexagonal steel structural bolt consists of one bolt, one nut, and two washers. The torsion shear steel structural bolt consists of one bolt, one nut, and one washer.