Stahlinstitut VDEh https://vdeh.de/en/standardisation/stahl-eisen-blatter/stahl-eisen-prufblatter/sep-1220-7/ – 11.08.2026

SEP 1220-7

Testing and Doc­u­ment­a­tion Guideline for the Join­ab­ility of thin sheet of steel – Part 7: Pro­jec­tion welding of fasteners.

The test methods spe­cified in this Stahl-Eisen test spe­cific­a­tion (SEP) describe the pro­cedure to determine the suit­ab­ility of auto­motive steel sheets for joining via the process of pro­jec­tion welding.

Exem­plar­ic­ally, a nut with seg­mented pro­jec­tions is welded to a thin steel sheet.

Described are sample pre­par­a­tion, welding equip­ment and test con­di­tions, determ­in­a­tion of quality levels, the test pro­cedure itself (visual testing, thread engage­ment, weld nut set-down, push-out and pull-out testing, torque testing, metal­lo­graphy), as well as doc­u­ment­a­tion of results. Example diagrams are given for testing and example sheets for the eval­u­ation of results.

1^st edition October 2025