A106 Gr.B Seamless Pipe Supplier India — ASTM A106 Grade B

ASTM A106 Grade B is a carbon-manganese seamless steel pipe designed for high-temperature service up to 425°C (800°F). It is the most widely used carbon steel pipe specification in power generation, refineries and process industries. Primary applications include boiler feedwater piping, steam distribution lines, refinery process piping, heat exchanger connections, power plant auxiliary piping, and general industrial process piping where operating temperatures exceed the limits of A53/API 5L grades. A106 Gr.B is specified when the piping system will see sustained elevated temperatures.

Both are carbon steel pipe specifications but differ in intended service. A106 is exclusively seamless and designed for high-temperature service (up to 425°C) — it has mandatory elevated temperature tensile testing and tighter chemical limits. A53 covers both seamless (Type S) and ERW (Type E) pipe for general service including structural, water, steam and gas lines at moderate temperatures. A106 Gr.B has minimum yield of 240 MPa and tensile of 415 MPa versus A53 Gr.B at 240/415 MPa — similar mechanical properties but A106 has additional high-temperature qualification.

We maintain comprehensive stock of ASTM A106 Grade B seamless pipe from 1/2 inch (15NB) to 24 inches (600NB) in all standard schedules: SCH 40 (standard weight), SCH 80 (extra heavy), SCH 120, SCH 140, SCH 160 and XXS (extra extra strong). Standard random lengths are 5.5 to 7.0 metres. Fixed-length pipes available with 3-day lead time. For heavy-wall applications (power plant headers, high-pressure steam), we stock SCH 120-XXS in sizes up to 24 inches. Typical inventory exceeds 500 tonnes across all sizes.

Yes, Creative Metal Industries supplies ASTM A106 Grade B seamless pipe with IBR Form III-C certification for boiler auxiliary piping, feedwater systems and steam distribution in Indian thermal power plants. Our IBR-certified A106 stock comes from approved mills including Jindal SAW, Maharashtra Seamless, ISMT and Bao Steel. Each pipe is marked with IBR stamp, heat number and grade identification. Documentation includes complete chemical and mechanical test results conforming to both ASTM A106 and Indian Boiler Regulation requirements.

ASTM A106 Grade B pipe has ASME allowable stress values up to 425°C (800°F) per ASME B31.1 Power Piping and B31.3 Process Piping codes. Above 425°C, the allowable stress drops significantly due to creep considerations and graphitisation risk in carbon steel. For service above 425°C, chrome-moly alloy grades such as P11 (1.25Cr-0.5Mo) or P22 (2.25Cr-1Mo) must be used. In practice, many engineers limit A106 Gr.B to 400°C for critical piping with long design life to provide adequate margin against time-dependent degradation.

ASTM A106 Grade B seamless pipe undergoes: hydrostatic testing at pressure calculated per ASTM A530 formula (or pneumatic test as alternative); tensile testing at room temperature confirming minimum 240 MPa yield and 415 MPa UTS; flattening test per ASTM A530; chemical analysis confirming C≤0.30%, Mn 0.29-1.06%, S≤0.035%, P≤0.035%; and for sizes over 2 inches, one bend test per heat. Optional supplementary requirements include ultrasonic examination (S4), hardness testing (S6) and elevated temperature tensile test. All our A106 pipe is supplied with MTC per EN 10204 3.1.