Description
Differential-pressure flow measurement
ASTM A182 F304L Weld Neck Orifice Flange
An ASTM A182 F304L weld neck orifice flange is a forged, tapped flange used as part of a differential-pressure flow measurement assembly.
What is an F304L weld neck orifice flange?
A matched pair holds an orifice plate between the flanges and provides pressure-tapping locations upstream and downstream. The bore, taps, facing and accessories must be coordinated with the metering design.
F304L is a practical low-carbon austenitic grade for general stainless process service where the specified corrosion environment does not require molybdenum-bearing or duplex material.
F304L weld neck orifice flange specifications
| Product | weld neck orifice flange |
|---|---|
| Material | F304L / UNS S30403 / EN 1.4307 |
| Material specification | ASTM A182 F304L |
| Dimensional standard | ASME B16.36 |
| Connection / form | Weld neck flange pair with pressure taps |
| Size and rating | Class 300, 400, 600, 900, 1500 and 2500 within ASME B16.36 limits |
| Surface / end detail | RF or RTJ facing and tap arrangement as ordered |
| Manufacturing route | Forging, heat treatment, CNC machining, drilling and tapping |
| Inspection documents | EN 10204 3.1 MTC, dimensional report and additional testing when specified |
Dimensions, tolerances and acceptance criteria follow the standard edition and project documents named on the purchase order. Published ranges are enquiry guidance, not a pressure-temperature design approval.
Material and dimensional standards
Material specification
ASTM A182 F304L is forged stainless material with UNS S30403. The flange dimensions and tap details are controlled separately by ASME B16.36.
Product dimensions
ASME B16.36 covers orifice flanges and pressure-tapping arrangements. Weld neck forms are ordered by NPS, class, bore, facing and tap configuration.
Typical applications and selection boundary
Applications are examples only. Confirm corrosion resistance, temperature limits, impact properties and code compliance for the actual service.
Manufacturing, inspection and documentation
SASA FLANGE can supply this product with identification linked to the raw-material heat. The agreed inspection and documentation plan is controlled by the purchase order.
Heat-number control and material certificate review.
Bore, hub, bolt circle, facing, tap location and threaded details.
PMI, PT, UT, hardness or third-party inspection when specified.
EN 10204 3.1 MTC and ordered inspection reports.
RFQ checklist
- Material grade and specification
- Dimensional standard and edition
- Nominal size
- Quantity and destination
- MTC, NDE and third-party inspection requirements
- Pressure class and bore / schedule
- RF or RTJ facing
- Tap type, orientation and accessory scope
Frequently asked questions
What should be included in an RFQ for an F304L weld neck orifice flange?
State the material specification, dimensional standard and edition, size, pressure class or wall thickness, end or facing detail, quantity, inspection requirements and delivery destination.
Can an F304L weld neck orifice flange be supplied with EN 10204 3.1 documentation?
Yes. EN 10204 3.1 material certification and heat-number traceability can be supplied. PMI, NDE, dimensional reporting or third-party inspection should be stated on the purchase order.
Is F304L suitable for every corrosive service?
No. Grade selection depends on the fluid chemistry, chloride level, temperature, pressure, fabrication route and governing design code. The project engineer should confirm service suitability.
Request a quotation
Send the standard, material, size, rating or wall thickness, quantity and inspection requirements for a technical and commercial review.
