Weld neck flanges
The tapered hub is butt-welded to the pipe, spreading stress away from the flange face. The standard choice for high pressure, high temperature and cyclic service, manufactured in every class and grade.
About weld neck flanges
A weld neck flange (WN) has a long tapered hub ending in a weld bevel that matches the pipe's wall. The bore matches the pipe bore, so flow is smooth and the joint can be fully radiographed.
Specify the pipe schedule or bore with your order, because the hub bore is machined to it. Long weld neck (LWN) versions are made for vessel nozzles.
Where it is used
- Process and refinery lines at Class 300 and above
- Steam, hot oil and thermal-cycling service
- Lines where the weld must be radiographed
- Vessel and equipment nozzles (long weld neck)
Need weld neck 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
What details do you need to quote a weld neck flange?
Size, class, facing, material grade, standard, and the pipe schedule or bore the hub must match, plus quantity.
What is the difference between WNRF and WNRTJ?
WNRF has a raised face for spiral-wound or sheet gaskets. WNRTJ has a ring-groove face for metal ring gaskets, used at high pressure and temperature.
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.