ASTM A370, ISO 6892-1, API5L, ISO 3183

Welded or seamless metal tubes require special arrangements for a proper tensile test

ISO 6892-1, ASTM A370, API5L, and ISO 3183 specifications contain tensile testing procedures which can present a variety of challenges based on the shape of the pipe, the wall thickness, and the radius.

The specimen can be a piece of whole tube or a part obtained from the tube, this for diameters higher than 60 mm. The full section tube must be plugged at each end with special bushings (whose drawings are mentioned in Standards) to avoid crushing during clamping in the inserts and tensile test. If the tube is too large, strips (tiles) are drawn and clamped with flat inserts. For the stress measurement, the methods require a 50 mm gauge length. Clip On or automatic extensometers can be used, that fit perfectly to the inside and outside diameter of the specimen, avoiding slipping on the irregular shape and ensuring accurate measurements.

For tube tensile tests, the most commonly used machine sizes are 250 or 600 kN.
We recommend wedge or parallel hydraulic grips.