1. Specifications & Capability
FUSHUN METAL forges large flanges – weld neck, blind and ring type – in F11, F22, F91, F304, F316 and F51, DN300-1500 mm, for petrochemical and power plant piping. Flanges are integrally forged, machined, and tested by ultrasonic and magnetic particle inspection.
Forging the flange from a single piece, with grain flow following the hub-to-ring contour, gives the pressure integrity a manway or nozzle connection demands, without the weld seam of a fabricated flange.
| Grade | Standard | Type |
|---|---|---|
| F11 / F22 / F91 | ASTM A182 | Cr-Mo alloy steel |
| F304 / F316 | ASTM A182 | Austenitic stainless |
| F51 | ASTM A182 | Duplex stainless |
2. Components & Service Conditions
These flanges are the manway and nozzle flanges of pressure vessels and the connection flanges of power plant piping. They seal against a gasket under pressure while carrying the bolting load, so both strength and the integrity of the sealing face matter.
The Cr-Mo grades (F11, F22, F91) are selected for elevated-temperature strength and hydrogen service, the austenitic F304/F316 for corrosion resistance, and the duplex F51 where chloride stress-corrosion cracking is a risk. The flange is integrally forged so the grain flow follows the hub contour, and ultrasonic plus magnetic particle inspection confirm soundness at the sealing surface.
3. Grade Equivalents – F11 / F22 / F91 / F304 / F316
| Designation | Standard | Notes |
|---|---|---|
| F11 | ASTM A182 | 1.25Cr-0.5Mo |
| F22 | ASTM A182 | 2.25Cr-1Mo |
| F91 | ASTM A182 | 9Cr-1Mo-V |
| F304 / F316 | ASTM A182 | Austenitic stainless |
| F51 | ASTM A182 | Duplex stainless |
| 13CrMo4-5 / 10CrMo9-10 | EN 10222 | European equivalents |
| Grade | C | Mn | Cr | Ni | Mo |
|---|---|---|---|---|---|
| F22 | 0.05-0.15 | 0.30-0.60 | 2.00-2.50 | – | 0.87-1.13 |
| F304 | 0.08 max | 2.0 max | 18.0-20.0 | 8.0-11.0 | – |
| F316 | 0.08 max | 2.0 max | 16.0-18.0 | 10.0-14.0 | 2.00-3.00 |
The chromium-molybdenum grades give elevated-temperature strength and hydrogen resistance; F316’s molybdenum improves pitting resistance over F304.
4. Manufacturing Process
Forging. FUSHUN METAL integrally forges the flange from a single billet, with grain flow following the hub-to-ring contour.
Heat treatment. Cr-Mo grades are quenched and tempered; stainless grades are solution annealed.
Machining. The flange is machined to the standard or drawing, including the gasket face and bolting holes.
Testing. UT and MT, with full traceability and inspection certificates under EN 10204 3.1.
5. Standards & Certification
Large forged flanges are supplied to ASTM A182 and EN 10222, with inspection certificates under EN 10204 3.1. FUSHUN METAL holds ISO 9001 and AS9120B certification.
Related forgings: wind turbine flanges and nuclear flange rings.
6. Typical Applications
Manway flanges
Flanges for pressure vessel manways.
Nozzle flanges
Flanges for vessel and pipe nozzles.
Power plant piping
Connection flanges for power station piping.
Petrochemical
Flanges for petrochemical process piping.
7. Inquiry Essentials
To quote your forged flange, please provide the flange standard, pressure rating, facing type, and the required grade.
