BSM Grade 304 Slotted Round Union Nut

Slotted Round Collar Geometry and C-Spanner Drive

This BSM slotted union nut (SKU series BSMSN25 through BSMSN100) is a cylindrical stainless steel collar nut machined with radial perimeter slots for C-spanner tightening. Internally, the nut features female union threads and an inward-turned rear flange that captures the collar of a mating BSM weld liner and draws it against a BSM male part.

Grade 304 Material and Non-Wetted Retainer Role

All six sizes in the retained subitem table are supplied in Grade 304 stainless steel. Because the union nut surrounds the outside of the liner and male thread without contacting the internal process fluid, Grade 304 provides structural thread strength and exterior washdown corrosion resistance on hygienic process lines.

Tabulated Dimensions (A and B) and SKU Codes

In the datasheet dimension table (in mm), axial nut thickness A is a constant 22.2 mm across all six sizes, while outer diameter B and SKU codes progress as follows: 1"/25.4 mm (BSMSN25, B = 52.5 mm), 1 1/2"/38.1 mm (BSMSN40, B = 66 mm), 2"/50.8 mm (BSMSN50, B = 77.5 mm), 2 1/2"/63.5 mm (BSMSN65, B = 88.5 mm), 3"/76.2 mm (BSMSN75, B = 101.6 mm), and 4"/101.6 mm (BSMSN100, B = 128 mm).

Selection and Mating Checks Notes

Match the nominal tube outside diameter (1" to 4") to the mating BSM weld liner (BSMWL series) and BSM male part (BSMMP series). Note that the datasheet cross-section labels axial thickness A and outer diameter B without printing the internal Whitworth thread pitch or slot width/depth.