ASTM A105 flanges are forged carbon steel flanges made to ASTM A105 / ASME SA105, the most widely used flange material in the world. They are the default choice for hydrocarbon, steam, water, air and utility piping at ambient and moderately elevated temperatures, matched to carbon steel pipe such as ASTM A106 Grade B and API 5L Grade B.
Raaj Fittings forges and machines A105 and normalised A105N flanges in-house at our two plants in India, from ½" to 60" and in Class 150 to Class 2500, with anti-rust protection for export, and supplies them to EPC contractors, fabricators and stockists across the Middle East, Europe and the Americas.
| Material specification | ASTM A105 / ASME SA105; A105N (normalised) |
|---|---|
| Dimensional standards | ASME B16.5 (½" to 24"), ASME B16.47 Series A and B (26" to 60"), EN 1092-1, DIN, BS 4504, JIS B2220, IS 6392 |
| Pressure class | ASME Class 150, 300, 600, 900, 1500 and 2500; PN 6 to PN 400 |
| Facing | Raised Face (RF), Flat Face (FF), Ring Type Joint (RTJ), Male & Female, Tongue & Groove |
| Surface protection | Rust-preventive coating; other coatings to your specification on request |
| Certification | EN 10204 3.1 mill test certificate as standard; EN 10204 3.2 on request |
| Element, % | ASTM A105 |
|---|---|
| Carbon (C) | 0.35 max |
| Manganese (Mn) | 0.60 – 1.05 |
| Phosphorus (P) | 0.035 max |
| Sulphur (S) | 0.040 max |
| Silicon (Si) | 0.10 – 0.35 |
| Copper (Cu) | 0.40 max |
| Nickel (Ni) | 0.40 max |
| Chromium (Cr) | 0.30 max |
| Molybdenum (Mo) | 0.12 max |
| Vanadium (V) | 0.08 max |
| Property | ASTM A105 |
|---|---|
| Tensile strength, min. | 485 MPa (70 ksi) |
| Yield strength, min. | 250 MPa (36 ksi) |
| Elongation in 50 mm, min. | 22% |
| Reduction of area, min. | 30% |
| Hardness, max. | 187 HBW |
ASTM A105 allows flanges to be supplied as forged, or heat treated by annealing, normalising, or normalising and tempering, depending on size and class. A105N means the flange has been normalised, which refines the grain, evens out properties across thick sections and improves toughness. Many oil and gas specifications, and most sour-service orders, call for A105N; give the condition on your enquiry.
| Standard | Comparable grade |
|---|---|
| ASTM / ASME | A105 / SA105 |
| EN 10222-2 | P250GH (1.0460) — comparable, not identical |
| DIN | C22.8 (1.0460) — comparable, not identical |
Every heat is PMI-verified and its chemistry and mechanical properties are confirmed against the material specification before the flanges are released. Each piece is marked with grade, size, rating and heat number for traceability to its EN 10204 3.1 mill test certificate. EN 10204 3.2 certification and inspection by the buyer's nominated third-party agency are available on request, as are PED 2014/68/EU compliance for European projects and IBR certification for Indian boiler applications.
A105N flanges have been normalised, a heat treatment that refines the grain and gives more uniform properties and better toughness. Plain A105 may be supplied as forged where the specification allows. Many oil and gas projects require A105N.
A105 is not impact tested, so it is normally limited to about −29 °C. For colder service, ASTM A350 LF2 flanges, impact tested at −46 °C, are specified.
Yes, when supplied to NACE MR0175 / ISO 15156, usually as normalised A105N with hardness limited to 22 HRC and the required documentation.
A105 flanges are normally welded to carbon steel pipe such as ASTM A106 Grade B, ASTM A53 Grade B or API 5L Grade B, with the weld neck bore matched to the pipe schedule.
They are coated with a rust-preventive or oiled, gasket faces are protected with covers, and they are packed in seaworthy wooden cases. Other coatings and packing to your specification are available on request.