DS-Series Sanitary Union Seal Ring

DS Sanitary Union Sealing Configuration

The DS sanitary union gasket seats inside the annular recess of a DS union male part and compresses against the mating weld liner when the union nut is tightened. Although the DS drawing shares dimensional values with the supplier's SMS seal chart, DS and SMS union hardware have distinct thread and groove conventions and should not be assumed interchangeable.

Five-Material Series Scope

Both the header specification block and the parameter table list PTFE, EPDM, Silicone, FKM, and NBR as available seal materials for the DS series. Because the gallery shows a blue profiled ring alongside a black ring without mapping each photograph to a specific compound, buyers must specify the exact elastomer or fluoropolymer material on the order.

1"–6" Range vs. Embedded 25–104 Drawing

The series parameter table states a nominal range of 1" to 6", whereas the embedded DS dimensional drawing tabulates six metric sizes: 25, 38, 51, 63.5, 76, and 104 (corresponding to 1" through 4"). Across those six rows, inside diameter A is 22.5–103.5 mm, outside diameter B is 31.8–115.8 mm, and thickness C is 4.2 mm for size 25 and 5.3 mm for sizes 38–104.

Selection and Mating Checks

For nominal sizes above 104 mm (up to 6") or when matching the photographed lipped ring profile rather than the rectangular schematic section, request exact per-size groove dimensions before assembly. Select the compound to suit the line fluid, operating temperature, and CIP cleaning regime.