Two ferrule compression tube fittings are manufactured under strict quality control program and close
tolerances. There is no international / national standard which is followed by tube fitting manufacturers to
manufacture these fittings. Every manufacturer have their own design and tolerances which governs the
This ensures there is no stress on the tube and tube do not twist or get distorted.
Front and back ferrules play vital role individually while fitting make up. Front ferrule does the sealing whereas
back ferrule performs gripping action. The firm grip of back ferrule on tube surface provides excellent
vibration fatigue resistance.
Silver plating on the nut threads act as lubricant and prevents galling. The nut can be backed off easily for disassembly and remakes. Usually the fittings are pulled up one and a quarter turn to make leak fee assembly.
During each re-assembly the nut should be advanced a quarter turn from its previous pulled up position to
ensure the adequate tightening and consistent leak free joint. Tube Fittings in smaller sizes less than 6 mm
need three quarter to one turn to make up the leak free joint.