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Large Diameter Stainless Steel Slip-on (SO) Flanges

Large Diameter Stainless Steel Slip-on (SO) Flanges

Stainless slip-on (SO) flanges. EN 1092-1 for covered sizes; larger sizes from drawings, up to DN3000.

Specifications

Pressure class
ASME Class 150–2500 and all PN ratings (EN 1092-1, GB/T 9124); non-standard per drawing
Size range
All standard sizes, up to DN3000; ASME B16.5 to NPS24, larger per B16.47 or drawing
Standard
EN 1092-1, GB/T 9124; ASME B16.5 (≤ NPS24); larger B16.47 or drawing
Facing
RF as usual; FF / RTJ per drawing
Bore
Matched to pipe OD
Grade
304/304L, 316/316L, 310S, 321, 2205, 2507
Forging material spec
ASTM A182 F304/F304L, F316/F316L, F321, F310, F51 (2205), F53 (2507)
Process
forged → solution annealed → machined and drilled → pickled and passivated
Inspection
MTR available on request; hydrotest/NDT and lead time per order
Marking
Hard stamping or ink marking, per standard or order
Certificates
ISO 9001/14001/45001, PED, DNV, BV, TÜV SÜD factory approvals; see this site’s Certificates page
Inquiry checklist
When inquiring, state: pressure class, size, grade, facing, standard or drawing; non-standard parts can be made to drawing or sample.
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A slip-on (SO) flange slides over the pipe and is fillet-welded. It is faster to align than a welding-neck flange. HuaboPipe supplies stainless SO flanges. Made to EN 1092-1, GB/T 9124 or ASME B16.5 (up to NPS 24); larger sizes to ASME B16.47 or drawing, up to DN3000. ASME Class 150–2500 and all PN ratings.

How to choose

Use SO when pressure is moderate and field alignment speed matters. Use WN for higher pressure, vibration or cyclic bending. Large SO flanges need a drawing; do not copy small-size catalog dimensions onto DN3000.

FAQ

What is the maximum SO size?

Up to DN3000. Large sizes are made from drawings.

Which standard do you follow?

Made to EN 1092-1, GB/T 9124 or ASME B16.5 (up to NPS 24); larger sizes to ASME B16.47 or drawing, up to DN3000. ASME Class 150–2500 and all PN ratings.

SO or WN?

SO is quicker to fit. WN is the better choice for high pressure, vibration or critical lines.

Which facing is standard?

RF. FF, RTJ or others are confirmed from the drawing.

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