Slip-on flanges
The pipe slides into the flange and is fillet-welded inside and outside. Easier to align and lower in cost than weld neck, for lower-pressure lines.
About slip-on flanges
A slip-on flange (SO) is bored slightly larger than the pipe OD. It needs less precise cutting and is quick to fit up, which makes it popular for utilities, cooling water and air lines.
It is generally used up to Class 300 and in non-cyclic service. For high pressure or thermal cycling a weld neck flange is preferred.
Where it is used
- Cooling water, air and utility lines
- Low-pressure process lines
- Fabricated ducts and tanks
- Lines where quick fit-up matters
Need slip-on flanges? Get a quotation from the manufacturer.
Send size, class, grade and quantity. We usually reply within one working day.
Dimensions by size and class
Pick a size and class. The cross-section, thickness, hub and bolting update on the drawing.
Flange dimension finder
Every ASME B16.5 dimension for weld neck, slip-on, socket weld, threaded, lap joint and blind flanges, Class 150 to 2500. The section redraws to scale as you change type, size and class.
Dimensions per ASME B16.5. The raised face is not included in thickness or hub length. Matching stud bolts come from Teshi Fasteners as a set.
Grades we manufacture
- A105 / A105N
- A350 LF2
- A694 F42–F70
- F11, F22, F91
- F304/304L
- F316/316L
- F321, F347, F310
- F904L
- F44 (254 SMO)
- F51 / F60 duplex
- F53 / F55 super duplex
- Titanium B381 F-1 to F-12
- Inconel 625, Incoloy 825
- Hastelloy C276
- Monel 400
- Alloy 20
- Cu-Ni 90/10, 70/30
Facings, marking, testing and packing
Facings
- Raised face (RF), serrated 125–250 AARH
- Flat face (FF)
- Ring-type joint (RTJ)
- Tongue and groove, male and female
Marking
Hard-stamped or stencilled with Teshi mark, size, class, grade, heat number, bore or schedule and standard, so every piece traces to its certificate.
Testing
- Dimensional and visual inspection
- PMI on alloy grades
- Hardness, impact (LF2), IGC (stainless) on request
- UT of forgings when your QAP calls for it
Packing
Faces protected, rust-preventive coating on carbon steel, packed in wooden cases or on pallets. Seaworthy packing for export orders.
Questions buyers ask
Is a slip-on flange as strong as a weld neck flange?
No. Its calculated strength under internal pressure is lower and fatigue life is shorter, which is why it is used for lower-pressure, non-cyclic service.
Get a quotation from the manufacturer
Send your BOQ, drawing or tender reference. You deal directly with the manufacturer.
- Reply from our estimation team, usually within one working day
- Carbon steel to titanium on one order
- EN 10204 3.1 or 3.2 certificates, third-party inspection welcome
- ISO 9001:2015 certified and IBR approved, since 1971
Drawings and BOQ spreadsheets are easiest by email. Mention your project name.