Alloy Steel Flanges are designed using alloyed steel compositions to provide high strength, corrosion resistance, and dependable services in high-temperature and high-pressure applications. Their mechanical characteristics are determined by alloying elements and heat treatment, and the international standards, including ASME, ASTM, and DIN, determine their dimensional accuracy. The flanges are common with critical piping
systems in oil, gas, petrochemical, power generation and chemical industries where durability and safety are paramount. ASTM A182 Alloy Steel Flanges come in F1, F5, F9, F11, F12, F22, F91, grades, which are chosen depending on the service conditions, and operating temperatures. The most common include weld neck, slip-on, socket weld, threaded and blind flanges, created to make sure that the pipeline systems have secure and leak-free connections. They are usually between 1/2 inch and 48 inches and meet the requirements of ASME B16.5 and B16.47 and have pressure classes of 150 to 2500.
Amardeep Steel Centre is a major producer, distributor and exporter of Alloy Steel Pipe Flanges of ASTM A182 based in Mumbai, India. Each product is manufactured through forged, machined, or fabricated processes and they are all certified with EN 10204 3.1 mill test certificates to make sure that they can be traced and their quality complies. These are alloy steel flanges designed to last long, provide uniform performance and dependable service in harsh industrial uses across the globe.
ASTM A182 Alloy Steel Flanges Specifications
All alloy steel flanges supplied by Amardeep Steel Centre are manufactured to the following standard specifications:
| Parameter | Details |
| Standard | ASTM A182 / ASME SA182 |
| Applicable Codes | ANSI Flanges, ASME Flanges, API, MSSSP, BS Flanges, DIN Flanges, EN Flanges, NACE |
| Size Range | 1/2 inch (15 NB) to 48 inch (1200 NB) |
| Dimensional Standards | ANSI/ASME B16.5, B16.47 Series A and B, B16.48, BS 4504, BS 10, EN 1092, DIN |
| Grades Supplied | ASTM/ASME A182 GR F5, F9, F11, F12, F22, F91 |
| Pressure Classes | 150, 300, 400, 600, 900, 1500, 2500 | PN6, PN10, PN16, PN25, PN40, PN64 |
| Face Types | Raised Face (RF), Flat Face (FF), Ring Type Joint (RTJ), Tongue and Groove |
| Manufacturing Method | Hot Forging and Rolling |
| Heat Treatment | Annealing, Normalizing, Quenching and Tempering (grade specific) |
| Test Certificates | EN 10204 3.1 and 3.2 Mill Test Certificates available |
| NDT Testing | UT, RT, MPT, LPT as per client requirements |
Chemical Composition of ASTM A182 Alloy Steel Flange Grades
| Grade | C (max) | Mn | Si | Cr | Mo | UNS No. |
| A182 F5 | 0.15 | 0.30 to 0.60 | 0.50 max | 4.00 to 6.00 | 0.44 to 0.65 | K41545 |
| A182 F9 | 0.15 | 0.30 to 0.60 | 0.50 to 1.00 | 8.00 to 10.00 | 0.90 to 1.10 | K90941 |
| A182 F11 Cl.2 | 0.05 to 0.15 | 0.30 to 0.60 | 0.50 to 1.00 | 1.00 to 1.50 | 0.44 to 0.65 | K11597 |
| A182 F12 Cl.2 | 0.05 to 0.15 | 0.30 to 0.60 | 0.50 max | 0.80 to 1.25 | 0.44 to 0.65 | K11562 |
| A182 F22 Cl.3 | 0.05 to 0.15 | 0.30 to 0.60 | 0.50 max | 2.00 to 2.50 | 0.87 to 1.13 | K21590 |
| A182 F91 | 0.07 to 0.14 | 0.30 to 0.60 | 0.20 to 0.50 | 8.00 to 9.50 | 0.85 to 1.05 | K90901 |
Mechanical Properties of ASTM A182 Alloy Steel Flange Grades
| Grade | Tensile Strength (MPa min) | Yield Strength (MPa min) | Elongation (% min) | Hardness (BHN max) |
| A182 F5 | 485 | 275 | 20 | 187 |
| A182 F9 | 620 | 415 | 18 | 207 |
| A182 F11 Cl.2 | 515 | 310 | 20 | 207 |
| A182 F12 Cl.2 | 485 | 275 | 20 | 163 |
| A182 F22 Cl.3 | 515 | 310 | 20 | 163 |
| A182 F91 | 585 | 415 | 20 | 248 |
Types of Alloy Steel Flanges
Amardeep Steel Centre manufactures all standard types of ASTM A182 alloy steel pipe flanges. Each type serves a distinct function in piping system design:
Industries Served by Alloy Steel Pipe Flanges
ASTM A182 alloy steel flanges are specified across industries where elevated temperature, high pressure, and corrosive media demand superior metallurgical performance compared to standard carbon steel:
- Oil and Gas: Wellhead equipment, pipeline fittings, riser systems. F11, F22, F91 grades.
- Petrochemical and Refinery: Reactor piping, hydrocracker units, catalytic reforming lines. F22 and F91 grades for creep resistance.
- Power Generation: Superheater piping, steam headers, boiler drum connections. F91 grade for ultra-high temperature service above 550 degrees C.
- Chemical Processing: Acid service lines, heat exchangers, pressure vessels. F5 and F9 grades for moderate high-temperature service.
- Fertilizer Plants: Ammonia synthesis loops, urea reactor piping. F11 and F22 grades standard specification.
- LNG and Gas Processing: Cryogenic and high-pressure pipelines in liquefied gas facilities. Selected grades based on Charpy impact testing results.
- Nuclear Power: High-purity water and steam lines requiring certified alloy steel components with full traceability.
Alloy Steel Flange Face Types
The face type determines the gasket seating surface and is critical for seal integrity at operating conditions:
| Face Type | Code | Key Characteristic |
| Raised Face | RF | Most common. Gasket seats on a raised ring. Used in Classes 150 through 2500. |
| Flat Face | FF | Full face gasket. Used when connecting to cast iron or non-metallic flanges to prevent cracking. |
| Ring Type Joint | RTJ | Metallic ring gasket seated in a machined groove. Superior sealing for high-pressure, high-temperature critical service. |
| Tongue and Groove | T and G | Male and female mating faces. Gasket fully confined. Used in pumps, compressors, and vessel nozzles. |
| Male and Female | M and F | Similar to tongue and groove but with a flat inner face. Provides positive gasket location. |
Alloy Steel Pipe Flanges Pressure Temperature Ratings
Maximum Allowable Working Pressure by Pressure Class (ASME B16.5, Alloy Steel F11)
| Pressure Class | At 100°F (38°C) | At 400°F (204°C) | At 700°F (371°C) | At 1000°F (538°C) |
| Class 150 | 285 PSI | 230 PSI | 200 PSI | 170 PSI |
| Class 300 | 740 PSI | 600 PSI | 520 PSI | 430 PSI |
| Class 600 | 1480 PSI | 1200 PSI | 1040 PSI | 860 PSI |
| Class 900 | 2220 PSI | 1795 PSI | 1560 PSI | 1295 PSI |
| Class 1500 | 3705 PSI | 2995 PSI | 2600 PSI | 2160 PSI |
| Class 2500 | 6170 PSI | 4990 PSI | 4335 PSI | 3600 PSI |
Applicable Standards and Dimensional References
Alloy steel flanges supplied by Amardeep Steel Centre are manufactured and inspected in accordance with the following internationally recognized standards:
| Standard | Scope |
| ASTM A182 / ASME SA182 | Material specification for forged alloy and stainless steel piping components for high-temperature service. |
| ANSI/ASME B16.5 | Pipe flanges and flanged fittings from NPS 1/2 through NPS 24. Covers pressure temperature ratings, materials, dimensions, tolerances, marking, and testing. |
| ANSI/ASME B16.47 Series A (MSS SP-44) | Large diameter steel flanges from NPS 26 through NPS 60. |
| ANSI/ASME B16.47 Series B (API 605) | Large diameter flanges with lighter construction for lower pressure ratings. |
| ASME B16.48 | Line blanks and spectacle blind flanges. |
| BS 4504 / EN 1092-1 | European flanges with PN pressure designations for metric pipe systems. |
| BS 10 | British Standard flanges in Tables D, E, F, H, and J. |
| DIN 2573 to 2638 | German standard flanges with PN pressure ratings. |
| API 6A / API 6B | Wellhead and Christmas tree equipment flanges for oil and gas applications. |
| MSS SP-44 | Large diameter carbon and alloy steel flanges. |
Alloy Steel Weld Neck Flange Weight Chart (ASME B16.5, Class 300)
Indicative weights for ASTM A182 alloy steel weld neck raised face flanges per ASME B16.5 Class 300. Actual weights may vary with grade density and manufacturing tolerances.
| NPS (inch) | OD of Flange (mm) | Raised Face OD (mm) | Bolt Circle (mm) | No. of Bolts | Approx. Weight (kg) |
| 1/2 | 95.3 | 34.9 | 66.7 | 4 | 0.5 |
| 3/4 | 117.3 | 42.9 | 82.6 | 4 | 0.9 |
| 1 | 123.8 | 50.8 | 88.9 | 4 | 1.1 |
| 1.1/2 | 155.7 | 73.0 | 114.3 | 4 | 2.3 |
| 2 | 165.1 | 92.1 | 127.0 | 8 | 3.2 |
| 3 | 209.5 | 127.0 | 168.3 | 8 | 6.4 |
| 4 | 254.0 | 157.2 | 200.1 | 8 | 11.3 |
| 6 | 317.5 | 215.9 | 266.7 | 12 | 22.7 |
| 8 | 381.0 | 269.9 | 330.2 | 12 | 38.6 |
| 10 | 444.5 | 323.9 | 387.4 | 16 | 62.1 |
| 12 | 520.7 | 381.0 | 450.9 | 16 | 95.3 |
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Our Manufacturing Process and Quality Control
- Raw Material Sourcing
Alloy steel billets and bars sourced from approved mills with mill test certificates conforming to ASTM A182 chemical requirements. - Hot Forging
Billets are heated and forged using hydraulic and mechanical presses to achieve the required grain structure and dimensional tolerances. - Heat Treatment
Grade-specific cycles including annealing, normalizing and tempering, or quenching and tempering, carried out in calibrated furnaces. - Machining
CNC turning and milling to achieve dimensional conformance with ASME B16.5 or B16.47 as applicable. - Inspection and Testing
Visual inspection, dimensional verification, PMI (Positive Material Identification), hardness testing, hydrostatic testing, and NDT as required. - Documentation
EN 10204 3.1 Mill Test Certificates, Inspection Reports, Packing Lists, and Country of Origin Certificates issued with each shipment. - Surface Treatment
Oil dip or anti-rust paint finish standard. Yellow zinc chromate or other coatings available as per purchase order requirements.
Related Products
- Alloy Steel Buttweld Fittings
- Alloy Steel Forged Fittings
- Alloy Steel Pipes and Tubes
- Alloy Steel Fasteners
Frequently Asked Questions About Alloy Steel Flanges
What grades are available in ASTM A182 Alloy Steel Flanges?
Amardeep Steel Centre supplies ASTM A182 alloy steel flanges in grades F5, F9, F11, F12, F22, and F91. Each grade offers distinct chromium and molybdenum content suited to specific temperature and pressure conditions. F91 is the highest-performing grade for ultra-high-temperature service above 550 degrees C.
What is the difference between ASME B16.5 and ASME B16.47 flanges?
ASME B16.5 covers flanges in NPS 1/2 through NPS 24. ASME B16.47 covers large diameter flanges in NPS 26 through NPS 60, in two series. Series A (formerly MSS SP-44) is heavier and used in high-pressure pipelines. Series B (formerly API 605) is lighter and suited for lower pressure rating applications.
What is the difference between F11 and F22 alloy steel flanges?
F11 is a 1.25Cr 0.5Mo chromium molybdenum grade suitable for service up to approximately 550 degrees C. F22 is a 2.25Cr 1Mo grade with higher chromium and molybdenum content, offering superior creep resistance at temperatures above 550 degrees C. F22 is the preferred choice for heavy-duty refinery and power plant piping.
Do you provide mill test certificates for alloy steel flanges?
Yes. All alloy steel flanges supplied by Amardeep Steel Centre are dispatched with EN 10204 3.1 Mill Test Certificates (MTC) as standard. EN 10204 3.2 certificates, certified by an independent third-party inspection agency, are available on request and commonly required for oil and gas and nuclear projects.
What NDT tests are performed on ASTM A182 alloy steel flanges?
Standard NDT options include Ultrasonic Testing (UT) for internal defects, Radiographic Testing (RT) for weld integrity, Magnetic Particle Testing (MPT) for surface cracks, and Liquid Penetrant Testing (LPT) for surface discontinuities. The specific test requirement is noted on the purchase order and the relevant test report is attached to the shipment documentation.
What is the lead time for alloy steel flanges?
Standard grades in common sizes from NPS 1/2 to NPS 24 are typically available from stock or within 2 to 4 weeks. Large diameter flanges above NPS 24, special grades, or non-standard pressure classes may require 4 to 8 weeks depending on forging schedule and testing requirements.
Global Supply and Export Destinations
Amardeep Steel Centre exports ASTM A182 alloy steel flanges to over 70 countries across six continents. Our primary export markets include the United States, United Arab Emirates, Saudi Arabia, Qatar, Kuwait, Oman, Malaysia, Singapore, Indonesia, United Kingdom, Germany, Netherlands, Italy, Australia, South Africa, and Brazil. All international shipments are supported with full documentation including commercial invoice, packing list, bill of lading, certificate of origin, and inspection reports.
We Supply Alloy Steel Flanges Across India
Domestic supply covers all major industrial hubs including Mumbai, Pune, Chennai, Coimbatore, Hyderabad, Ahmedabad, Surat, Vadodara, Bengaluru, Delhi NCR, Kolkata, Vizag, Rajkot, and all port cities. Dispatches from our Mumbai warehouse enable same-state delivery within 24 to 48 hours.
Amardeep Steel Centre supplies ASTM A182 alloy steel pipe flanges to engineering contractors, procurement teams, and OEM manufacturers worldwide. Our technical team can assist with grade selection, dimensional specification, and test certificate requirements for your project.
To place an order or receive a detailed quotation, contact us at: info@amardeepsteel.com or call +91-XXXXXXXXXX