DIN welding liners make up one side of a DIN union and fit into the welding male with a gasket of choice. The round nut then presses the welding liner and welding male together compressing the gasket and forming a tight seal.
DIN 11851 fittings are used extensively throughout Europe and the UK, and as such are the most common European fittings encountered in the US. A complete DIN union consists of a slotted DIN round nut, a threaded welding male, a gasket and welding liner. The welding male and welding liner are available in both Imperial and metric tube sizes, however the threads of the welding male and round nut are always measured in metric (mm) sizes. The most common points of confusion are two fold:
Incorrect sizing is common with DIN 11851 fittings. Please review our DIN 11851 Guide for assistance in sizing your DIN 11851 fitting.