GNEE offers a full range of general-purpose ferritic and martensitic stainless steel tubes according to ASTM A268/A268M standards, including seamless and welded tubes, with outer diameters ranging from 6 mm to 273 mm, wall thicknesses from 0.5 mm to 25 mm, and lengths up to 25 meters. This includes major grades such as TP405, TP410, TP420, TP430, TP430Ti, TP439, TP444, and TP446.
Surface treatments include annealing and pickling, bright finish, polishing, or mirror polishing, and the tubes exhibit excellent mechanical properties. For example, TP420 has a yield strength of ≥345MPa and a tensile strength of ≥520MPa, making it suitable for continuous operation at temperatures up to approximately 600°C. It is an ideal choice for boilers, heat exchangers, condensers, and process piping, as well as high-strength components in petrochemical plants.
ASTM A268 Stainless Steel Tubing Specification
| Item | Specification |
|---|---|
| Standard | ASTM A268 / ASME SA268 |
| Steel Grades | TP409, TP410, TP430, TP446 |
| Manufacturing Type | Seamless / Welded |
| Outer Diameter | 6 mm – 508 mm |
| Wall Thickness | 0.7 mm – 25 mm |
| Length | 6 m, 12 m, or customized |
| Surface Finish | Pickled, Annealed, Polished |
| Heat Treatment | Annealed / Normalized |
| Inspection | UT, Eddy Current, Hydrostatic |
| Tolerance | As per ASTM A268 |
Chemical Composition (Typical, %)
| Grade | C | Cr | Ni | Ti | Fe |
|---|---|---|---|---|---|
| TP405 | ≤0.08 | 11.5–14.5 | ≤0.5 | Stabilized | Balance |
| TP409 | ≤0.08 | 10.5–11.75 | ≤0.5 | Optional | Balance |
| TP410 | ≤0.15 | 11.5–13.5 | ≤0.75 | - | Balance |
| TP430 | ≤0.12 | 16.0–18.0 | ≤0.75 | - | Balance |
Mechanical Properties (Annealed Condition)
| Grade | Tensile Strength (MPa) | Yield Strength (MPa) | Elongation (%) |
|---|---|---|---|
| TP405 | ≥415 | ≥205 | ≥22 |
| TP409 | ≥380 | ≥170 | ≥20 |
| TP410 | ≥450 | ≥275 | ≥20 |
| TP430 | ≥450 | ≥205 | ≥22 |
ASTM A268 Stainless Steel Tubing Price (Reference)
| Grade | Reference Price (USD/kg) |
|---|---|
| TP405 | 2.2 – 3.0 |
| TP409 | 2.5 – 3.3 |
| TP410 | 2.6 – 3.6 |
| TP430 | 3.5 – 4.8 |
Surface Condition
All tubes shall be free of excessive mill scale, suitable for inspection. A slight amount of oxidation will not be considered as scale. Any special finish requirements shall be subject to agreement between the manufacturer and the purchaser.
Product Marking
In addition to the marking described in Specification A1016/A1016M, the marking shall indicate whether the tubing is seamless or welded. Marking Sample:GNEE ASTM A268/A268M UNS S44400 SMLS 44.5 X 4 X 12000MM HEAT NO. XXXXXX MADE IN CHINA
GNEE, with 18 years of experience in pipe manufacturing, is a trustworthy supplier of stainless steel pipes. The factory not only produces standard-sized annealed steel pipes but also offers extended pipes of 18 meters and 25 meters to meet the needs of different customers. The factory is fully equipped with facilities including cold rolling mills, smokeless furnaces, pickling tanks, ultrasonic eddy current cleaning machines, and physical and chemical laboratories.
Packaging: Bundled, horizontally strapped.
Marking: Paint or labels are applied to the bundle surface, indicating the required information.
Surface Treatment: 2B and No.1
Testing: Chemical composition analysis, tensile test, flattening test, impact test, leak test, dimensional test, and visual inspection.
Test Certificates: Factory test certificate, TPL report, and raw material certificate.
Delivery Time: Stock items ship immediately, customized products 15-30 days.
Value-added services: Pre-treatment, parts cutting, third-party inspection, and sample services.
