Analysis of possible problems during the installation of card sleeve joints

● Installation

1 Saw the seamless steel pipe of suitable length to remove the burrs at the port. The end surface of the pipe should be perpendicular to the axis, and the angle tolerance should not be greater than 0.5°. If the pipe needs to be bent, the length of the straight section from the end of the pipe to the bend shall not be less than three times the length of the nut.

2 Set the nut and ferrule on the seamless steel pipe. Pay attention to the direction of the nut and the ferrule, do not install it backwards.

3 Apply lubricating oil to the thread and ferrule of the pre-assembled joint body, insert the pipe into the joint body, (the pipe must be inserted to the end) and tighten the nut by hand.

4 Tighten the nut until the ferrule catches the pipe. This turning point can be felt by the increase in tightening torque (pressure point).

5 After reaching the pressure point, tighten the compression nut 1/2 turn.

6 Remove the pre-assembled joint body and check the embedding of the edge of the ferrule. The visible protruding band must fill the space on the end of the ferrule. The ferrule can be rotated slightly, but it cannot be moved axially.

7 For final installation, apply lubricating oil to the thread of the joint body in the actual installation, and tighten the compression nut until the sensible tightening force increases. Then tighten 1/2 turn to complete the installation.

● Repeat installation

All ferrule joints can be reassembled many times, but the parts must be undamaged and clean.

1 Insert the pipe into the joint body until the ferrule is close to the cone surface of the joint body, and tighten the nut by hand.

2 Tighten the nut with a wrench until the tightening torque increases sharply, and then tighten it by 1/4 to 1/2 turn.

● Check

The pipe can be removed to check whether the assembly meets the requirements: there should be even slight protrusions on the pipe at the end of the ferrule. The ferrule cannot slide back and forth, but a slight rotation is allowed.

● Cause of leakage

1 The tube is not inserted all the way.

2 The nut is not tightened.