DIN 14A Stepped Butt-Weld Union Liner Ferrule

DIN 14A Stepped Union Liner Construction

The DIN 14A Liner Ferrule is the unthreaded stepped weld liner of a DIN sanitary pipe union. Machined from 304L stainless steel, the body consists of a cylindrical butt-weld neck and a stepped outer retention collar. The rear face of the collar catches the inward flange of a DIN 13R slotted round nut, while the front face compresses a DIN union gasket into the recess of a mating DIN 15A male ferrule.

Distinction from DIN 15A Male and SMS 14A Liners

Although both DIN and SMS union liners use the '14A' series designation in the supplier catalog, they are dimensionally distinct. The DIN 14A liner covers seven metric sizes including DN32 (1-1/4 inch), with collar outside diameters (C) from 1.46 inch (DN25) to 4.69 inch (DN100) and overall lengths (A) from 0.87 inch to 1.73 inch, whereas the SMS 14A liner is shorter (0.61 inch to 1.18 inch) and sized for Swedish union nuts.

Published DN25 to DN100 Dimensional Envelope

Across the seven cataloged sizes—DN25 (1 inch), DN32 (1-1/4 inch), DN40 (1-1/2 inch), DN50 (2 inch), DN65 (2-1/2 inch), DN80 (3 inch), and DN100 (4 inch)—published dimension B spans 1.00 inch to 3.94 inch, dimension A spans 0.87 inch to 1.73 inch, and collar OD C spans 1.46 inch to 4.69 inch.

Weld Neck Checks and Nut Assembly Sequence

Verify tube OD matching and slip the DIN round nut onto the pipe prior to welding the 14A liner.