ANSI/AWS B4.0 details the requirements for the mechanical testing of welds. A portion of this standard describes the tensile testing of welds. The tensile test may be performed on specimens cut transverse or longitudinal to the centerline of the weld. The desired result is usually limited to the
Ultimate Tensile Strength since these specimens are non-homogeneous. Tensile tests may also be carried out on the base metal and weld metal to determine the mechanical properties for these materials and results can include Ultimate Tensile Strength,
Offset Yield Strength,
Yield Point,
Total Elongation and
Reduction of Area. Testing should be carried out according to the requirements of ASTM E8.
An equipment solution may need to accommodate both flat and round type machined specimens. If testing welded pipe or tubing, the system may also need to accommodate full round specimens up to a nominal diameter of 3 inches. For these reasons, we typically recommend our SATEC Series DX or HDX dual space machine with built-in wedge grips for testing flats or rounds. The dual space design can also accommodate any bend testing requirements in the lower compression test space. You can also include an extra conditioner channel and an extensometer for the measurement of strain. Materials testing software packages will automatically generate results for the necessary calculations listed above.
Welded specimens can often exhibit a bend along their length. In order to maintain axial alignment, the machine needs to be durable and produce enough clamping force to overcome some minor bending in the specimens. That is why we suggest using the SATEC Series DX. Load on the specimen is also measured directly using strain gauged load cell technology allowing the hydraulic system to be properly sealed and protected from contamination. This type of system also stands up better to the effects of off-center loading generated by slightly bent specimens.