1. Test sleeve:
The thread of the straight thread sleeve shall be full without cracks, and the inner and outer surfaces of the sleeve shall be free of corrosion and other obvious defects; The internal thread size shall be inspected with a special thread plug gauge. The standard is that the screw in length of the plug gauge shall not exceed 3P, and the plug gauge can be screwed in smoothly. In addition, the appearance quality of the connecting sleeve shall be inspected one by one according to relevant standards. Every 500 internal thread size inspection is an inspection batch, and each batch shall be randomly inspected according to 10%.
2. Reinforcement connection:
In the process of connection, the specifications of reinforcement and sleeve shall be consistent. During connection, the appearance of reinforcement and sleeve threads shall be checked to see whether they are clean and damaged. If any nonconformity is found, it shall be reworked or replaced. 2) During construction, use a working wrench to tighten the head of the screw in the middle of the sleeve. 3) After the reinforcement connection is tightened, use a torque wrench to detect the tightening torque value of the joint.
3. Joint inspection:
(1) After the reinforcement connection is completed, there shall be exposed effective threads outside the sleeve, but the exposed effective threads shall not exceed 2p on one side. The unqualified reinforcement connection关节应当及时更换或其他effective connection measures shall be taken.
(2) After the appearance quality is qualified, take 500 joints with the same conditions, materials, grades and specifications as an inspection batch, randomly select 15% and no less than 75 joints in the structure under construction to inspect their tightening torque, and the tightening torque value shall meet the specified requirements.
(3) For the acceptance of each batch of joints, three test pieces shall be randomly selected for the tensile strength test of the joints, and then the joint quality shall be evaluated according to the grade required by the design.
