Tubing Data For LOCK-FIT Fittings

In order to assure maximum fitting reliability and performance, great care should be given when selecting the tubing for each application.

Tube Selection

Four variables must be considered when ordering tube for use with LOCK-FIT fittings::
1. Material
2. Tube wall thickness
3. Tube surface finish
4. Tube hardness

Tubing should comply with standard ASTM A213 or ASTM A269, be seamless, and fully annealed.
The tube must be free of scratches and suitable for bending and flaring.

Tube OD Tolerances:

Ovality of twice OD tolerance is not suitable for LOCK-FIT fittings.
The tube must be reasonably round.
The ends of the tube must be free of burrs.
Tubing hardness: The hardness of the tube must be lower than the hardness of the fitting material.
The hardness must be not more than Rockwell HRB 80.