DIN round nuts fit over the threads of the welding male, and secure the welding liner and gasket inside the welding male. A DIN wrench is used to tighten the nut by hooking the wrench into the round nut grooves and turning in a clockwise direction. Round nuts are combined with other same DIN fittings based on the metric size.
DIN wrenches hook into the grooves on the round nut and allow the nut to be fully tightened following hand tightening. While the DIN wrenches may overlap in size, it is generally recommended to use a 3 - 6 in. spanner wrench for nuts 80mm or larger.
Incorrect sizing is common with DIN 11851 fittings. Please review our DIN 11851 Guide for assistance in sizing your DIN 11851 fitting.