Phanuphong Steel and Plates is a reputable manufacturer and supplier based in Bangkok, Thailand, known for delivering top-notch steel products and pipes tailored for demanding industrial needs. One of their standout offerings, Alloy Steel P11 Pipes, is highly regarded for its remarkable strength, durability, and adherence to international standards. These pipes are engineered to perform reliably even in high-pressure and high-temperature environments, making them crucial for sectors like oil and gas, petrochemical, power generation, and chemical processing. Phanuphong Steel is committed to providing superior material quality, precise dimensions, and prompt delivery, establishing themselves as a dependable partner for both local and global industrial and infrastructure projects.
Alloy Steel P11 Pipes are primarily made from carbon steel that’s enhanced with chromium, molybdenum, and manganese, which boosts their strength, hardness, and resistance to corrosion. On a mechanical level, they showcase impressive tensile and yield strength, outstanding toughness, and resilience against wear, oxidation, and thermal stress. These pipes are built to last and perform reliably under tough conditions, and they also boast excellent weldability. The strong composition and mechanical characteristics of Alloy Steel P11 Pipes make them ideal for high-pressure and high-temperature applications in the oil and gas, petrochemical, and power generation sectors.
| Type | Seamless / ERW / Welded / Fabricated |
| Standard | ASTM A335 P11, SA335 P11 (with IBR Test Certificate) |
| Craft | Cold rolled and Cold drawn |
| Length | Standard Double & In Cut length also. |
| Schedules | SCH 40, SCH 80, SCH 160, SCH XS, SCH XXS, All Schedules |
| Size | 1/2” NB to 36” NB |
| Tolerance | Cold drawn pipe: +/-0.1mm
Cold rolled pipe: +/-0.05mm |
| Specialized in | Large Diameter ASTM A335 P11 Pipe |
| available in Form of | Round, Square, Rectangular, Hydraulic Etc. |
| Application | Seamless Ferritic Alloy-Steel Pipe for High-Temperature Service |
| End | Plain End, Beveled End, Treaded |
| Additional Testing | NACE MR 0175, NACE TM0177, NACE TM0284, HIC TEST, SSC TEST, H2 SERVICE, IBR, etc. |
| Thickness | 3-12mm |
| Alloy Steel P11 | C | Cr | Mn | Mo | P | S | Si |
| 0.05 – 0.15 | 1.00 – 1.50 | 0.30 – 0.60 | 0.44 – 0.65 | 0.025 max | 0.025 max | 0.50 – 1.00 |
| Tensile Strength, MPa | Yield Strength, MPa | Elongation |
| 415 min | 205 min | 30 min |
We provide products that come with both mill test certificates and third-party test certificates, ensuring the highest standards of quality and compliance.
Phanuphong Steel is a major manufacturer and a supplier of premium Alloy Steel P11 pipe in Bangkok, the Thailand. With specialization in steel solutions, we offer a variety of products including carbon steel, alloy steel, light steel and galvanized steel. Our wide bearing has pipes, pipes, flanges, pipe fittings, forged fittings, sheets and plates. We are famous for our reliable distribution and extraordinary customer service, and are committed to offering high quality steel materials that ensure durability and better performance in different industrial applications. We are committed to skill, and we are your reliable partners for all steel requirements.
| ASTM | ASME | Equivalent Material | JIS G 3458 | UNS | BS | DIN | ISO | ABS | NK | LRS |
|---|---|---|---|---|---|---|---|---|---|---|
| A335 P11 | SA335 P11 | T11 | STPA 23 | K11597 | 3604 P1 621 | – | – | ABS 11 | KSTPA 23 | – |
| O.D.(mm) x Thickness(mm) | O.D(mm) x Thickness(mm) | O.D(mm) x Thickness(mm) |
|---|---|---|
| 38.1 x 3.2 | 57.0 x 4.9 | 76.2 x 4.0 |
| 38.1 x 4.0 | 57.0 x 6.3 | 76.2 x 5.0 |
| 38.1 x 6.3 | 57.0 x 7.9 | 76.2 x 6.3 |
| 42.4 x 3.2 | 60.3 x 3.2 | 82.5 x 4.5 |
| 42.4 x 4.0 | 60.3 x 3.6 | 88.9 x 3.2 |
| 44.5 x 3.2 | 60.3 x 5.0 | 88.9 x 3.6 |
| 44.5 x 6.3 | 63.5 x 3.2 | 88.9 x 4.0 |
| 48.3 x 3.2 | 63.5 x 3.6 | 101.6 x 3.6 |
| 48.3 x 3.6 | 63.5 x 4.0 | 101.6 x 4.5 |
| 50.8 x 4.5 | 63.5 x 6.3 | 101.6 x 6.3 |
| 51.0 x 3.2 | 63.5 x 7.9 | 114.3 x 3.6 |
| 51.0 x 3.6 | 70.0 x 3.2 | 114.3 x 5.0 |
| 51.0 x 6.3 | 70.0 x 3.6 | 139.7 x 4.0 |
| 57.0 x 3.2 | 70.0 x 6.3 | 139.7 x 5.0 |
| 57.0 x 3.6 | 76.2 x 3.6 | 139.7 x 6.3 |
| ASTM A335 P11 Pipe Size NPS | Pipe O.D. | Wall Thickness | Pipe I.D. | Weight per Foot |
| 1/2 | 0.84 | 0.109 | 0.622 | 0.85 |
| 0.147 | 0.546 | 1.09 | ||
| 0.188 | 0.464 | 1.31 | ||
| 0.294 | 0.252 | 1.72 | ||
| 3/4 | 1.05 | 0.113 | 0.824 | 1.13 |
| 0.154 | 0.742 | 1.48 | ||
| 0.219 | 0.612 | 1.95 | ||
| 0.308 | 0.434 | 2.44 | ||
| 1 | 1.315 | 0.133 | 1.049 | 1.68 |
| 0.179 | 0.957 | 2.17 | ||
| 0.250 | 0.815 | 2.85 | ||
| 0.358 | 0.599 | 3.66 | ||
| 1 1/4 | 1.66 | 0.140 | 1.380 | 2.27 |
| 0.191 | 1.278 | 3.00 | ||
| 0.250 | 1.160 | 3.77 | ||
| 0.382 | 0.896 | 5.22 | ||
| 1 1/2 | 1.90 | 0.145 | 1.610 | 2.72 |
| 0.200 | 1.500 | 3.63 | ||
| 0.281 | 1.338 | 4.86 | ||
| 0.400 | 1.100 | 6.41 | ||
| 2 | 2.375 | 0.109 | 2.157 | 2.64 |
| 0.154 | 2.067 | 3.66 | ||
| 0.218 | 1.939 | 5.03 | ||
| 0.250 | 1.875 | 5.68 | ||
| 0.281 | 1.813 | 6.29 | ||
| 0.344 | 1.687 | 7.47 | ||
| 0.436 | 1.503 | 9.04 | ||
| 2 1/2 | 2.875 | 0.120 | 2.635 | 3.53 |
| 0.203 | 2.469 | 5.80 | ||
| 0.216 | 2.443 | 6.14 | ||
| 0.250 | 2.375 | 7.02 | ||
| 0.276 | 2.323 | 7.67 | ||
| 0.375 | 2.125 | 10.02 | ||
| 0.552 | 1.771 | 13.71 |
You’ll find Alloy Steel P11 Pipes commonly used in oil and gas pipelines, petrochemical facilities, power generation systems, and chemical processing units where high-pressure and high-temperature performance is a must. They excel at transporting steam, water, oil, and other industrial fluids through critical piping networks. Thanks to their impressive mechanical strength, corrosion resistance, and durability, they are perfect for fabrication, structural, and engineering applications. With consistent performance and a long service life, Alloy Steel P11 Pipes are the go-to choice for industries that need safe, efficient, and high-performance piping solutions in challenging environments.
Phanuphong Steel is a leading manufacturer, supplier and exporter of high-quality Carbon Steel, Alloy Steel, Mild Steel and Galvanized Steel products. Our extensive product range includes Pipes, Tubes, Flanges, Pipe Fittings, Forged Fittings, Sheets and Plates, catering to various industries in Bangkok, Thailand.
Copyright 2025 Phanuphong Steel. All rights reserved
