The Big Three: What Makes a Swagelok® Tube Fitting Superior

Tube grip, gas seal, and vibration protection

When evaluating tube-fitting performance, look for these Big Three factors: tube grip, gas seal, and vibration protection. You should expect a tube fitting to deliver outstanding performance in all three areas, and Swagelok patented two-ferrule fitting design gives you what you are looking for.

Tube grip

Swagelok's hinging collecting action puts more of the back ferrule's surface in contact with the tubing. This provides more material for direct axial support and colleting squeeze. You won't get that with a bowing ferrule or from the bite type. With Swagelok, you get a stronger seal under maximum working pressure.

Gas seal

A Swagelok tube fitting forms a gas seal by means of the burnishing that occurs in two places: between the front ferrule and the tube fitting body, and between the front ferrule and the tubing.

Vibration protection

Bending, deflection and vibration puts stress on tubing. With a bite type of fitting, all three stress factors can become amplified at the stress riser, where the ferrule bites into the tubing. That can lead to tube fractures. Any extra vibration, pulsation, thermal shock or side load exerted on the fitting, the minimal contact of a bite type fitting offers minimal support behind the bite. That raises the risk of pull-out or damage to the tube.

Any place where the fitting comes into contact with the tubing can become a point of concentrated stress. Swagelok's patented colleting action puts more of the back ferrule in contact with the tubing. The protected stress riser reduces the damaging effect of system vibration.