YUHONG GROUP has more than 35 years of experience in supplying alloy steel, stainless steel, duplex stainless steel, nickel alloy, titanium, and copper alloy piping products. The supply range includes seamless and welded pipes and tubes, forged flanges, butt weld fittings, forged fittings, heat exchanger tubes, tube bundles, tubesheets, and other drawing-based components. Applicable certifications and approvals held by our group companies and manufacturing facilities include CE, TÜV, LR, ABS, DNV, BV, KR, PED, AD 2000, CCS, TS, CNNC, ISO 9001, ISO 14001, OHSAS 18001, and ISO 45001, subject to the scope and validity of the relevant certificates.
ASTM A182 F22 Alloy Steel BLRF Flange
ASTM A182/A182M – Forged or rolled alloy and stainless steel pipe flanges, forged fittings, valves, and parts for high-temperature and pressure-system service.
ASME SA-182/SA-182M – ASME-adopted material specification for forged or rolled alloy and stainless steel piping components.
ASME B16.5 – Dimensions, pressure-temperature ratings, materials, tolerances, marking, and testing requirements for pipe flanges and flanged fittings from NPS 1/2 through NPS 24. ASME B16.5 includes Classes 150, 300, 400, 600, 900, and 1500 through NPS 24, and Class 2500 through NPS 12.
ASME B16.47 – Large-diameter steel flanges from NPS 26 through NPS 60 in Classes 75, 150, 300, 400, 600, and 900. Series A and Series B dimensions shall be specified in the purchase order.
ASME B16.36 – Orifice flanges used for differential-pressure measurement systems.
ASME B16.48 – Line blanks, spectacle blinds, paddle blinds, and paddle spacers.
MSS SP-44 – Steel pipeline flanges where specified by the piping design or purchase order.
EN 10204 – Inspection documentation, including Type 3.1 or Type 3.2 certification when ordered.
The applicable standard edition, dimensional system, pressure class, facing, pipe schedule, supplementary requirements, and inspection scope shall be stated in the purchase order.
| Element | Composition % |
|---|---|
| C | 0.05 – 0.15 |
| Mn | 0.30 – 0.60 |
| Si | 0.50 max |
| P | 0.040 max |
| S | 0.040 max |
| Cr | 2.00 – 2.50 |
| Mo | 0.87 – 1.13 |
| Fe | Balance |
| Property | Value |
|---|---|
| Tensile Strength, min | 515 MPa (75 ksi) |
| Yield Strength (0.2% offset), min | 310 MPa (45 ksi) |
| Elongation in 50mm, min | 20% |
| Reduction of Area, min | 30% |
| Brinell Hardness Number (HBW) | 156 – 207 |
The following table summarises the mandatory heat treatment provisions for Grade F22 low‑alloy steel flanges, as extracted from ASTM A182
| Requirement | Details |
|---|---|
| Cooling before treatment | After hot working, forgings shall be cooled to a temperature below 538 °C (1000 °F) prior to any heat treatment operation. |
| Heat treatment options | Grade F22 shall be heat treated per Table 1. Either normalized and tempered or liquid quenched and tempered (if agreed between manufacturer and purchaser) is permitted. The selection is at the manufacturer’s option unless the purchase order specifies otherwise. |
| Temperature ranges | Normalizing: 927–954 °C (1700–1750 °F); Tempering: minimum 677 °C (1250 °F). For liquid quenching, the same austenitising range is used, followed by tempering at ≥677 °C. |
Blind Ring Flange (BLRF), Weld Neck Ring Flange (WNRF), Slip-On Ring Flange (SORF), Socket Weld Ring Flange (SWRF), Threaded Ring Flange, Lap Joint Ring Flange (LJRF), Ring Type Joint Flange (RTJF)
Forged flanges can also be produced in other ASTM A182 grades upon request, including:
Low‑alloy: F1, F5, F9, F11, F12, F91
Carbon steel: A105
Stainless: F304/304L/304H, F316/316L/316H/316Ti, F317L, F321/321H, F347/347H, F904L
Duplex / Super duplex: F44, F51, F53, F55, F60, F61
Nickel alloys per ASTM B564 (Monel, Inconel, Incoloy, Hastelloy, etc.)
ASTM A182 F22 BLRF flanges are used in high‑temperature, high‑pressure piping systems, including:
Oil and gas refineries (hydrocrackers, hydrotreaters, hydrogen recycle lines)
Power generation (steam piping, boiler headers)
Petrochemical plants (reformer outlet, hot separator nozzles)
Marine and hydraulic systems where elevated temperatures are encountered
All products are supplied with full mill test certificates, and third‑party inspection (e.g., TÜV, DNV, LR, ABS) is available upon request.
