Flanges
Weld neck, slip-on, blind and special flanges in carbon steel and stainless steel — ASME B16.5/B16.47 — stocked in Tunisia for all pressure classes.
Request a QuoteFlanges for All Pressure Classes
Flanges are the primary means of connecting piping to equipment, valves and other piping systems. Correct flange selection — type, pressure class, material and facing — is critical to system performance and leak integrity.
Tecflow Energy stocks weld neck, slip-on, blind, socket-weld and threaded flanges in carbon steel and stainless steel, from ½″ to 24″ NPS, in ASME pressure classes #150 through #2500.
Flanges We Stock
Weld Neck Flanges (WN)
The most robust flange type, with a long tapered hub welded directly to the pipe. Preferred for high-pressure, high-temperature and cyclic service.
- ½″ to 24″ NPS, #150 to #2500
- Material: ASTM A105N (CS), A182 F316L (SS)
- Raised face (RF), flat face (FF), ring type joint (RTJ)
- Bore matched to pipe schedule on request
Slip-On Flanges (SO)
A lower-cost alternative to weld neck for non-critical service. The flange slips over the pipe and is double-welded.
- ½″ to 24″ NPS
- Material: ASTM A105N
- Raised face standard
- Not recommended for high-temperature or cyclic service
Blind Flanges (BL)
Used to close off pipeline ends, nozzles and vessel openings. Available in all pressure classes.
- ½″ to 24″ NPS, #150 to #2500
- Material: A105N (CS), A182 F316L (SS)
- RF and RTJ facing available
- Custom drilling patterns available
Special Flanges
Lap joint, socket-weld, threaded, spectacle and spade flanges, orifice flanges and long weld neck (LWN) nozzle flanges.
- Lap joint flanges for stub-end assemblies
- Orifice flanges to ASME B16.36
- Spectacle and spade blinds
- Long weld neck (LWN) nozzle flanges
Standards & Specifications
Product Standards
- ASTM A105N — CS forged flanges
- ASTM A182 F316L — SS forged flanges
- ASTM A694 — High yield flanges
- ASTM A350 LF2 — Low temperature CS flanges
Dimensional Standards
- ASME B16.5 — Pipe flanges ½″ to 24″
- ASME B16.47 — Large diameter flanges 26″ to 60″
- ASME B16.36 — Orifice flanges
- EN 1092-1 — European PN series flanges available
Testing
- EN 10204 3.1 material certificates
- Hardness testing
- PMI testing available
- Dimensional inspection per B16.5/B16.47
- NACE MR0175 compliant grades available
Marking
- ASME/ASTM marking to B16.5 requirements
- Heat number traceable to MTC
- Pressure class, material and size marking
- Country of origin
Why Buy from Tecflow?
Common sizes and pressure classes held in stock for immediate dispatch.
ASTM material certifications, dimensional inspection and PMI available.
Flanges bored to match your pipe schedule on request.
NACE MR0175 / ISO 15156 compliant grades stocked for sour service.
Frequently Asked Questions
What is the difference between weld neck and slip-on flanges?
Weld neck flanges have a long tapered hub and are welded to the pipe with a single butt weld — the most robust connection, preferred for critical service. Slip-on flanges slide over the pipe and are double-welded (inside and outside fillet welds) — lower cost but not suitable for high-temperature, high-pressure or cyclic service.
What does #150, #300, #600 mean for flanges?
These are ASME pressure classes, defining the pressure-temperature rating of the flange. Class 150 is the lowest pressure rating, suitable for moderate pressures. Class 2500 is the highest class in ASME B16.5 and is used for very high-pressure applications. The allowable working pressure depends on the class and the material.
Need Flanges for Your Project?
Send us your flange schedule and we'll confirm stock and pricing within 24 hours.