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Stainless Steel Lap Joint Flanges
Stainless Steel Lap Joint Flanges
Stainless Steel Lap Joint Flanges
Stainless Steel Lap Joint Flanges
Stainless Steel Lap Joint Flanges
Stainless Steel Lap Joint Flanges

Stainless Steel Lap Joint Flanges

A lap joint flange is a loose backing flange used with a stub end, so the flange can rotate to line up the bolt holes. HuaboPipe supplies lap joint flanges to order, usually with a matching stub end.

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
Matches stub-end face; RF common
Matched with
Used with stub end
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.

A lap joint flange is a loose backing flange used with a stub end, so the flange can rotate to line up the bolt holes. HuaboPipe supplies lap joint flanges to order, usually with a matching stub end. 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 lap-joint + stub end when joints are opened often or bolt holes must rotate. Order the stub end with the flange.

FAQ

Do we need a stub end?

Yes. A lap-joint flange is incomplete without the matching stub end.

Maximum size?

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.

Same as socket weld?

No. Socket weld inserts the pipe. Lap joint is a loose flange on a stub end.

Non-standard?

Yes. Send a drawing.

See all our forged flanges →