Weld Neck Flange Supplier
A weld neck flange is only as reliable as the forging behind it. Sourcing from a weld neck flange supplier who casts instead of forges, or who outsources heat treatment to hit a delivery date, puts the integrity of your entire pipe stress calculation at risk.
MFC Flange is a fully integrated weld neck flange & forging supplier, forging, machining, and heat treating every flange under one roof at our facility in Sealy, Texas, to ASME B16.5 and B16.36 standards.
Weld neck flanges are the default specification in high-pressure and high-temperature piping systems because the tapered hub transfers stress gradually into the pipe wall rather than concentrating it at a mechanical joint. That design advantage only holds up if the forging is sound. As a weld neck forging supplier, we control the grain structure of every flange from raw billet through final machining, so the mechanical properties your project specifies are the properties that ship.
Why Engineers Specify Weld Neck Flanges
We also produce reducing weld neck flanges for transitions between pipe diameters, eliminating the need for a separate reducer fitting and its associated welds in the assembly. Face type is selected to match your gasket and bolting design: raised face (RF) construction is the standard for most Class 150 through Class 2500 applications, while flat face (FF) configurations are specified where a mating flange, valve, or piece of equipment is itself flat-faced, most commonly in cast iron or low-pressure systems where a raised face would over-stress a brittle mating component.
Request A Quote
Whether your project calls for a single quick-turn weld neck flange or a volume order supporting a stocking program, MFC Flange has the forging capacity and material inventory to deliver on your timeline. To confirm grade, pressure class, and face type availability for your weld neck flange requirement, contact us or request a quote today.
Pressure Classes, Grades & Face Types
- 300 Series stainless steel for corrosion resistance in chemical processing, food and beverage, and pharmaceutical service, available in grades including 304/H, 316/L, 317/L, and 347/H
- Duplex stainless steel where chloride resistance and high mechanical strength are required, particularly in offshore and subsea applications
- High nickel alloys, including Hastelloy, Inconel, and Monel, for service beyond the corrosion or temperature limits of standard austenitic grades
- Chrome alloys for surface hardness and wear resistance in high-pressure process environments
Every weld neck flange is machined to the dimensional and tolerance requirements of ASME B16.5 for standard pipe sizes and ASME B16.36 for orifice applications, with DIN EN 1092 available where a project specifies international standards.
Certifications That Support Compliant Procurement
A weld neck flange & forging supplier without documentation is a liability on any project with an audit trail. Our facility is ISO 9001:2015 certified. Our inventory is BABA-ready for federally funded infrastructure work. We are approved across nearly all major Approved Manufacturer Lists (AMLs) and hold Canadian Registration Numbers across multiple provinces, supporting procurement on both sides of the border.
Material verification is performed in-house through Positive Material Identification (PMI), with tensile testing, Charpy impact testing, and hardness testing (BHN) documented and traceable through our ISO 9001 quality system. For engineers specifying into oil and gas, petrochemical, and power generation systems, that documentation trail is what confirms the flange on the shop floor matches the flange on the purchase order.
Frequently Asked Questions
What is the difference between a standard weld neck flange and a long weld neck flange?
A standard weld neck flange is designed to butt weld directly to a length of pipe, with the tapered hub transferring stress into the pipe wall at the weld joint. A long weld neck flange, also called a nozzle flange, is manufactured with an extended hub that functions as an integral nozzle rather than requiring a separate flange-and-pipe weld combination. Long weld neck flanges are typically specified for pressure vessel and tank fabrication, where a single continuous forging eliminates an additional weld joint and the inspection points that come with it. Our team can confirm which configuration is appropriate for your application based on your drawing and service conditions.
When should I specify a raised face instead of a flat face weld neck flange?
Raised face (RF) construction is the standard face type for most Class 150 through Class 2500 weld neck flanges and is appropriate wherever the mating flange is also raised face. Flat face (FF) construction is specified when the mating equipment, valve, or flange is itself flat-faced, most often cast iron components or low-pressure systems, since bolting a raised face flange against a flat-faced, brittle mating part can over-stress and crack it. If your drawing does not specify face type, confirm it against the mating component before ordering.
What pressure classes and material grades are available for weld neck flanges?
We produce weld neck flanges across the full ASME pressure class range, from Class 150 through Class 2500, in stainless steel, duplex stainless steel, high nickel alloys, and chrome alloys. All weld neck flanges are manufactured to ASME B16.5 for standard pipe sizes and ASME B16.36 for orifice applications, with DIN EN 1092 available for projects requiring international specifications. If your Bill of Materials calls for a specific grade and pressure class combination, contact our team to confirm current availability and lead time.