SMS 14A Stepped Butt-Weld Union Liner Ferrule

SMS 14A Stepped Union Liner Construction

The SMS 14A Liner Ferrule is the unthreaded stepped weld liner of a Swedish-standard SMS sanitary pipe union. Machined from 304L stainless steel, the fitting features a butt-weld tube neck and a stepped outer collar that seats inside the rear flange of an SMS 13R slotted round nut while pressing the union seal against a mating SMS 15A threaded male ferrule.

Distinction from DIN 14A Liners and SMS 15A Male Ferrules

Although both SMS and DIN liners use the '14A' series code in the supplier catalog, the SMS 14A liner is built for inch-based tubing (1 inch through 4 inch, without a DN32 size) and has a more compact axial envelope: overall length (A) is 0.61 inch to 1.18 inch and collar OD (C) is 1.40 inch to 4.65 inch, compared with 0.87 inch to 1.73 inch length on the DIN 14A liner.

Published 1" to 4" SMS Dimensional Table

Across the six cataloged sizes—1 inch (25 mm), 1-1/2 inch (38 mm), 2 inch (51 mm), 2-1/2 inch (63.5 mm), 3 inch (76.1 mm), and 4 inch (101.6 mm)—dimension B spans 1.00 inch to 4.00 inch, overall length A spans 0.61 inch to 1.18 inch, and collar OD C spans 1.40 inch to 4.65 inch.

Pre-Weld Nut Placement and Tube Check

Confirm whether dimension B (1.00 inch to 4.00 inch) represents nominal tube OD or bore ID for your wall schedule, and slide the SMS round nut onto the tube before welding.