Tubewell Steel & Engg. Co. is a leading manufacturer and stockist specializing in Alloy Steel Pipes, Tubes, Fittings and Flanges for critical industrial applications.
1% Chromium – 0.5% Molybdenum seamless alloy steel pipes for steam piping, boiler headers and moderate-temperature process service.
Tubewell Steel & Engg. Co. manufactures and stocks ASTM A335 P12 pipes – a 1Cr-½Mo ferritic alloy steel with a lower silicon limit than P11. P12 combines dependable creep strength, good ductility and excellent weldability, making it an economical choice for steam lines, boiler headers and process piping operating at moderate elevated temperatures.
A cost-effective Cr-Mo grade for steam and process lines
ASTM A335 P12 is a seamless ferritic alloy steel pipe containing 0.80–1.25% chromium and 0.44–0.65% molybdenum, with silicon limited to 0.50% max. Chromium improves oxidation and graphitisation resistance compared with carbon-moly steels, while molybdenum increases creep strength for continuous service up to about 565°C (1050°F). P12 also offers a slightly higher minimum yield strength (220 MPa) than P11.
P12 pipes are supplied full or isothermal annealed, normalized and tempered (minimum tempering temperature 650°C / 1200°F), or subcritically annealed. Tubewell stocks hot-finished and cold-drawn P12 pipes in all standard schedules with complete heat traceability, EN 10204 3.1 mill test certificates, IBR documentation on request and third-party inspection by BV, TÜV, SGS, Lloyd's or EIL.
Standard supply range for ASTM A335 P12 pipes
| Parameter | Details |
|---|---|
| Standard | ASTM A335, ASME SA335 |
| Grade | P12 (UNS K11562) |
| Type | Seamless – Hot Finished / Cold Drawn |
| Size (NB) | 1/2" NB to 24" NB |
| Outer Diameter | 21.3 mm to 610 mm |
| Wall Thickness | SCH 10, 20, 40, STD, 60, 80, XS, 100, 120, 140, 160, XXS |
| Length | Single Random, Double Random, Cut Length (up to 12 m) |
| Ends | Plain End, Bevelled End, Threaded |
| Heat Treatment | Full / Isothermal Annealed, Normalized & Tempered (temper min. 650°C) or Subcritical Annealed |
| ASME P-Number | P-No. 4, Group 1 |
| Surface | Black Painted, Varnished, Anti-rust Oil, Pickled |
| Dimension Standard | ASME B36.10M |
| Testing | Hydrostatic, Ultrasonic, Eddy Current, Flattening, Flaring, Hardness, PMI |
| Certificates | EN 10204 3.1 / 3.2, IBR Form III-A, TPI Reports |
International equivalents of A335 P12
| Standard | ASTM | UNS | EN | DIN / W.Nr. | JIS | BS |
|---|---|---|---|---|---|---|
| P12 | A335 P12 | K11562 | 13CrMo4-5 | 1.7335 | STPA 22 | 3604 HFS 620-460 |
Weight %, as per ASTM A335
| Grade | C | Mn | P | S | Si | Cr | Mo |
|---|---|---|---|---|---|---|---|
| A335 P12 | 0.05 – 0.15 | 0.30 – 0.61 | 0.025 max | 0.025 max | 0.50 max | 0.80 – 1.25 | 0.44 – 0.65 |
Minimum values at room temperature
| Grade | Tensile Strength | Yield Strength (0.2%) | Elongation (Long.) | Elongation (Trans.) |
|---|---|---|---|---|
| A335 P12 | 415 MPa (60 ksi) min | 220 MPa (32 ksi) min | 30% min | 20% min |
Typical values (for reference)
| Property | Metric | Imperial |
|---|---|---|
| Density | 7.85 g/cm³ | 0.284 lb/in³ |
| Melting Range | 1450 – 1510 °C | 2640 – 2750 °F |
| Modulus of Elasticity | 205 GPa | 29.7 × 10³ ksi |
| Thermal Conductivity (100°C) | 38 W/m·K | 22.0 BTU/h·ft·°F |
| Mean Thermal Expansion (20–300°C) | 12.4 µm/m·°C | 6.9 µin/in·°F |
| Specific Heat | 0.46 J/g·°C | 0.11 BTU/lb·°F |
| Max. Service Temperature | ≈ 565 °C | ≈ 1050 °F |
As per ASME B36.10M – wall thickness (mm) / weight (kg/m)
| NPS | OD (mm) | SCH 40 WT | SCH 40 Wt | SCH 80 WT | SCH 80 Wt | SCH 160 WT | SCH 160 Wt |
|---|---|---|---|---|---|---|---|
| 1/2" | 21.3 | 2.77 | 1.27 | 3.73 | 1.62 | 4.78 | 1.95 |
| 3/4" | 26.7 | 2.87 | 1.69 | 3.91 | 2.20 | 5.56 | 2.90 |
| 1" | 33.4 | 3.38 | 2.50 | 4.55 | 3.24 | 6.35 | 4.24 |
| 1 1/4" | 42.2 | 3.56 | 3.39 | 4.85 | 4.47 | 6.35 | 5.61 |
| 1 1/2" | 48.3 | 3.68 | 4.05 | 5.08 | 5.41 | 7.14 | 7.25 |
| 2" | 60.3 | 3.91 | 5.44 | 5.54 | 7.48 | 8.74 | 11.11 |
| 2 1/2" | 73.0 | 5.16 | 8.63 | 7.01 | 11.41 | 9.53 | 14.92 |
| 3" | 88.9 | 5.49 | 11.29 | 7.62 | 15.27 | 11.13 | 21.35 |
| 4" | 114.3 | 6.02 | 16.07 | 8.56 | 22.32 | 13.49 | 33.54 |
| 6" | 168.3 | 7.11 | 28.26 | 10.97 | 42.56 | 18.26 | 67.56 |
| 8" | 219.1 | 8.18 | 42.55 | 12.70 | 64.64 | 23.01 | 111.27 |
| 10" | 273.1 | 9.27 | 60.29 | 15.09 | 95.98 | 28.58 | 172.33 |
| 12" | 323.9 | 10.31 | 79.71 | 17.48 | 132.05 | 33.32 | 238.76 |
| 14" | 355.6 | 11.13 | 94.55 | 19.05 | 158.10 | 35.71 | 281.70 |
| 16" | 406.4 | 12.70 | 123.30 | 21.44 | 203.53 | 40.49 | 365.35 |
| 18" | 457.0 | 14.27 | 155.80 | 23.83 | 254.55 | 45.24 | 459.37 |
WT = Wall Thickness in mm, Wt = Weight in kg/m. Values are nominal; actual weights may vary within ASTM tolerances.
Where ASTM A335 P12 pipes are used
Steam piping, feed lines and boiler headers in thermal stations.
Superheater links and headers in process and utility boilers.
Moderate-temperature hydrocarbon and steam process piping.
Reactor feed and hot utility lines in chemical processing.
Shell-side and connection piping operating at elevated temperature.
Co-generation steam piping in sugar, pulp and paper plants.
Quality you can verify on every heat
Large inventory for fast dispatch
MTC EN 10204 3.1 / 3.2
Positive material identification
Pan-India & export shipping
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