Phanuphong Steel and Plates, a prominent manufacturer and supplier located in Bangkok, Thailand, specializes in top-notch Carbon Steel JIS G3445 Pipes. Known for their reliability and precision, Phanuphong Steel delivers products that adhere to strict international standards, ensuring durability and performance across a variety of industrial applications. With a strong focus on customer satisfaction, the company offers an extensive range of sizes and specifications designed to meet the needs of the construction, energy, and manufacturing sectors. Their expertise in steel production, combined with advanced processing techniques, makes them a trusted partner for businesses in search of high-quality Carbon Steel piping solutions.
Carbon Steel JIS G3445 Pipes are mainly made from low to medium carbon steel, striking a perfect balance between strength and ductility. The key alloying elements—carbon, manganese, phosphorus, and sulfur—are carefully controlled to ensure consistent mechanical performance. These pipes boast impressive tensile strength, yield strength, and elongation properties, making them resistant to deformation under pressure. Plus, they offer good weldability and machinability, which simplifies installation and fabrication. Their carefully controlled composition guarantees reliable performance in high-stress situations while remaining cost-effective and compliant with JIS G3445 standards.
| Standard | : | JIS G3445 |
| Description Name | : | STKM 11A Steel tube, STKM 12A steel tubes, STKM 12C steel tubes, STKM 13A steel tubes, STKM 13C steel tubes |
| Size | : | 6mm-340mm |
| Wall Thickness | : | 1mm-50mm |
| Shape | : | Round |
| Production Type | : | Cold drawn, cold rolled or hot rolled |
| Length | : | Single random length/ Double random length or as customer’s actual request max length is 10m |
| Grade | : | STKM 11A, STKM 12A, STKM 12C, STKM 12B, STKM 13A, STKM 13B, STKM 13C, STKM 15A, STKM 17A |
| C | Si | Mn | P | S |
| max  0.12 | max  0.35 | max  0.6 | max  0.04 | max  0.04 |
| Assortment | Yield point or Proof stress | Tensile strength | Elongation | Reduction of area | Charpy impact strength |
| – | N/mm 2 | N/mm 2 | % | % | J/cm 2 |
| Tubes | Â | 290 | 35 | Â | Â |
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 trusted manufacturer and supplier of high-quality Carbon Steel JIS G3445 Pipe products in Bangkok, Thailand. Specializing in premium steel materials, we offer a diverse range of products, including Carbon Steel, Alloy Steel, Mild Steel, and Galvanized Steel. Our extensive inventory features Pipes, Tubes, Flanges, Pipe Fittings, Forged Fittings, Sheets, and Plates. With a strong commitment to timely delivery and exceptional customer service, Phanuphong Steel ensures the supply of top-grade materials that deliver superior performance in various industrial applications. Trust Phanuphong Steel for all your Carbon Steel JIS G3445 Pipe needs.
| Permissible Specified Outside Diameter and Specified Wall Thickness | ||
| Specified Outside Diameter D mm (in.) | Specified Wall Thickness t mm (in.) | |
| Special Light Sizes a | Regular Sizes | |
| ≥ 10.3 (0.405) to < 13.7 (0.540) | — | ≥ 1.7 (0.068) to ≤ 2.4 (0.094) |
| ≥ 13.7 (0.540) to < 17.1 (0.675) | — | ≥ 2.2 (0.088) to ≤ 3.0 (0.118) |
| ≥ 17.1 (0.675) to < 21.3 (0.840) | — | ≥ 2.3 (0.091) to ≤ 3.2 (0.125) |
| ≥ 21.3 (0.840) to < 26.7 (1.050) | — | ≥ 2.1 (0.083) to ≤ 7.5 (0.294) |
| ≥ 26.7 (1.050) to < 33.4 (1.315) | — | ≥ 2.1 (0.083) to ≤ 7.8 (0.308) |
| ≥ 33.4 (1.315) to < 48.3 (1.900) | — | ≥ 2.1 (0.083) to ≤ 10.0 (0.394) |
| ≥ 48.3 (1.900) to < 60.3 (2.375) | — | ≥ 2.1 (0.083) to ≤ 12.5 (0.492) |
| ≥ 60.3 (2.375) to < 73.0 (2.875) | ≥ 2.1 (0.083) to ≤ 3.6 (0.141) | > 3.6 (0.141) to ≤ 14.2 (0.559) |
| ≥ 73.0 (2.875) to < 88.9 (3.500) | ≥ 2.1 (0.083) to ≤ 3.6 (0.141) | > 3.6 (0.141) to ≤ 20.0 (0.787) |
| ≥ 88.9 (3.500) to < 101.6 (4.000) | ≥ 2.1 (0.083) to ≤ 4.0 (0.156) | > 4.0 (0.156) to ≤ 22.0 (0.866) |
| ≥ 101.6 (4.000) to < 168.3 (6.625) | ≥ 2.1 (0.083) to ≤ 4.0 (0.156) | > 4.0 (0.156) to ≤ 25.0 (0.984) |
| ≥ 168.3 (6.625) to < 219.1 (8.625) | ≥ 2.1 (0.083) to ≤ 4.0 (0.156) | > 4.0 (0.156) to ≤ 40.0 (1.575) |
| ≥ 219.1 (8.625) to < 273.1 (10.750) | ≥ 3.2 (0.125) to ≤ 4.0 (0.156) | > 4.0 (0.156) to ≤ 40.0 (1.575) |
| ≥ 273.1 (10.750) to < 323.9 (12.750) | ≥ 3.6 (0.141) to ≤ 5.2 (0.203) | > 5.2 (0.203) to ≤ 45.0 (1.771) |
| ≥ 323.9 (12.750) to < 355.6 (14.000) | ≥ 4.0 (0.156) to ≤ 5.6 (0.219) | > 5.6 (0.219) to ≤ 45.0 (1.771) |
| ≥ 355.6 (14.000) to < 457 (18.000) | ≥ 4.5 (0.177) to ≤ 7.1 (0.281) | > 7.1 (0.281) to ≤ 45.0 (1.771) |
| ≥ 457 (18.000) to < 559 (22.000) | ≥ 4.8 (0.188) to ≤ 7.1 (0.281) | > 7.1 (0.281) to ≤ 45.0 (1.771) |
| ≥ 559 (22.000) to < 711 (28.000) | ≥ 5.6 (0.219) to ≤ 7.1 (0.281) | > 7.1 (0.281) to ≤ 45.0 (1.771) |
| ≥ 711 (28.000) to < 864 (34.000) | ≥ 5.6 (0.219) to ≤ 7.1 (0.281) | > 7.1 (0.281) to ≤ 52.0 (2.050) |
| ≥ 864 (34.000) to < 965 (38.000) | — | ≥ 5.6 (0.219) to ≤ 52.0 (2.050) |
| ≥ 965 (38.000) to < 1422 (56.000) | — | ≥ 6.4 (0.250) to ≤ 52.0 (2.050) |
| ≥ 1422 (56.000) to < 1829 (72.000) | — | ≥ 9.5 (0.375) to ≤ 52.0 (2.050) |
| ≥ 1829 (72.000) to < 2134 (84.000) | — | ≥ 10.3 (0.406) to ≤ 52.0 (2.050) |
Thanks to their strength, durability, and versatility, Carbon Steel JIS G3445 Pipes are widely utilized across various industries. In construction, they are used as structural supports, scaffolding, and for water or gas pipelines. The oil and gas industry depends on them for transporting fluids and handling high-pressure applications. Manufacturing sectors employ these pipes for machinery, automotive parts, and industrial equipment. Their resistance to corrosion and mechanical stability also make them ideal for power plants, chemical processing, and infrastructure projects. Phanuphong Steel ensures that these pipes meet rigorous quality standards, providing peace of mind for their customers.
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.
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