Directions for assembly of Tube Nut

PDF Download

When assembling a tube nut and sleeve to tubing there are certain steps that need to be taken to insure that a good seal is achieved. Either a tube fitting body or pre-installation body can be used. The following steps illustrate how this process is completed.


Cut the pipe square, remove all internal
and external burrs.


Oil internal threading and cone thoroughly.
Thoroughly oil both ring and nut (do
not grease).
Fit both ring and nut onto the pipe.
Be careful not to fit the ring the
wrong way.


5. Screw on the nut by hand until it touches.


6. Push the tube against the thrust of internal cone.
A4-TUBENUT-77. Screw on until the pipe cannot turn any more. Draw a mark on the nut to improve the convenience of checking the number of turns to be given.
A4-TUBENUT-88. Give the nut a 3/4 turn, the ring clamps the pipe (the pipe must not rotate).


9. Final clamping is achieved by tightening the nut 3/4 of a turn. Thus, the ring is sunk into the pipe wall.


10. Next, loosen the nut and check the upset flange fills the whole cutting face of the ring. Otherwise, tighten a bit more. It does not matter if the ring rotates on the pipe.
A4-TUBENUT-1111. After loosening, the final tightening of the nut should not require excessive pressure.
A4-TUBENUT-12NOTE: The straight portion of the pipe must be 2 times the height “H” of the nut as a minimum.