What is bend testing and why do we do it?

A Welder test specimen is being tested through a guided bend test while a Certified Sr. Welding Inspector is witnessing

Bend testing is a type of  destructive testing of weldment. Bending tests are carried out to ensure that a metal has sufficient ductility to stand bending without fracturing. A standard specimen is bent through a specified arc and in the case of strip, the direction of grain flow is noted and whether the bend is with or across the grain. This test is quantitative test only.  It is done for Welder’s Qualification Test and Welding Procudure Qualification.

Bend testing is done either by side bend test, root bend or face bend test or combination thereof depending on the project or code requirements.

As per ASME IX, welder’s test piece shall be checked by 100% visual inspection plus bend test or in lieu of bend test, radiographic testing. However, many projects are requiring both the  bend test and radiographic testing. Bend test is done after acceptance of radiographic testing. If in case, the test piece passed the radiographic testing and failed the bend testing, the overall result will be FAILED.