ASTM A268 Ferritic and Martensitic Stainless Steel Tubing
- Grade: TP405, TP410, TP429, TP430, TP443, TP446-1, TP446-2, TP409, TP439, TP430Ti, TP468
- Tube OD: 4-127mm
- Tube WT: 0.4-12.7mm
- Length: 1000-12000mm
- Type: Seamless & Welded
Features
ASTM A268 Seamless and Welded Ferritic and Martensitic Stainless Steel Tubing for General Service
Chemical Composition (wt.%)
| Element | TP405 | TP410 | TP429 | TP430 | TP443 | TP446-1 | TP446-2 | TP409 | TP439 | TP430Ti | TP468 |
| C, max | 0.08 | 0.15 | 0.12 | 0.12 | 0.2 | 0.2 | 0.12 | 0.08 | 0.07 | 0.03 | 0.03 |
| Mn, max | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.50 | 1.50 | 1.00 | 1.00 | 1.00 | 1.00 |
| P, max | 0.04 | 0.04 | 0.04 | 0.04 | 0.04 | 0.04 | 0.04 | 0.045 | 0.04 | 0.04 | 0.04 |
| S, max | 0.03 | 0.03 | 0.03 | 0.03 | 0.03 | 0.03 | 0.03 | 0.045 | 0.03 | 0.03 | 0.03 |
| Si, max | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 |
| Ni | 0.50 max | – | – | – | 0.75 max | 0.75 max | 0.50 max | 0.80 max | 0.50 max | – | 0.5 |
| Cr | 11.5-14.5 | 11.5-13.5 | 14.0-16.0 | 16.0-18.0 | 18.0-23.0 | 23.0-27.0 | 23.0-27.0 | 10.5-11.7 | 17.0-19.0 | 17.0-19.0 | 18.00-20.00 |
| Mo | – | – | – | – | – | – | – | – | – | – | 0.2-1.2 |
| Al | 0.10-0.30 | – | – | – | – | – | – | – | – | – | – |
| Cu | – | – | – | – | 0.90-1.25 | – | – | – | – | – | – |
| N | – | – | – | – | – | – | 0.25 | – | 0.04 | – | 0.03 |
| Ti | – | – | – | – | – | – | – | – | 0.20 + 4(C+N) min | 0.20-1.00 | – |
Mechanical Properties
| Property | TP405 | TP410 | TP429 | TP430 | TP443 | TP446-1 | TP446-2 | TP409 | TP439 | TP430Ti | TP468 |
| Tensile strength, min, ksi [MPa] | 60 [415] | 60 [415] | 60 [415] | 60 [415] | 70 [485] | 70 [485] | 65 [450] | 55 [380] | 60 [415] | 60 [415] | 60 [415] |
| Yield strength, min, ksi [MPa] | 30 [205] | 30 [205] | 35 [240] | 35 [240] | 40 [275] | 40 [275] | 40 [275] | 25 [170] | 30 [205] | 35 [240] | 30 [205] |
| Elongation in 2 in. or 50 mm, min, % | 20 | 20 | 20 | 20 | 20 | 18 | 20 | 20 | 20 | 20 | 22 |
| Brinell Hardness, max | 207 | 207 | 190 | 190 | 207 | 207 | 207 | 207 | 190 | 190 | 207 |
| Rockwell Hardness, B Scale, max | 95 | 95 | 90 | 90 | 95 | 95 | 95 | 95 | 90 | 90 | 95 |
Technical Specifications
| Specification | Value |
| Standard | ASTM A268/A268M Seamless and Welded Ferritic and Martensitic Stainless Steel Tubing for General Service |
| Grade | TP405, TP410, TP429, TP430, TP443, TP446-1, TP446-2, TP409, TP439, TP430Ti, TP468 |
| Manufacturing Process | Hot Finished, Cold Finished, Welded |
| Seam Type | Seamless, Welded |
| Dimension | Tube OD: 4-127mm Tube WT: 0.4-12.7mm |
| Length | 1000-12000mm |
| Delivery Condition | Annealed |
| Inspection Certificate | EN 10204 Type 3.1 (Mill Test Certificate), EN 10204 Type 3.2 (Witness Testing or 3rd Party Inspection) |
| Test | Chemical analysis, Tension tests, Flaring tests, Hydrostatic tests, Air underwater pressure tests, Nondestructive electric tests |
Packing
The tubes are neatly arranged or bundled, lined with PVC bags, and placed inside the wooden crate.
Application
1. Automotive Industry
Exhaust systems: Tubes from grades like TP409 and TP439 are commonly used in automotive exhaust systems due to their high resistance to oxidation, corrosion, and heat, especially in environments exposed to exhaust gases and high temperatures.
Mufflers and catalytic converters: ASTM A268 ferritic tubes, particularly TP409, are ideal for muffler systems and catalytic converters where cost-effective corrosion resistance is required.
2. Heat Exchangers and Boilers
Heat exchangers: Martensitic stainless steel tubes (e.g., TP410) are used in heat exchangers due to their excellent thermal conductivity, corrosion resistance, and ability to withstand high-temperature service.
Boilers and superheaters: Ferritic stainless steel grades like TP446 are used in boilers and superheaters because they are excellently resistant to scaling and oxidation at elevated temperatures.
3. Petrochemical Industry
Refineries and chemical plants: ASTM A268 martensitic grades (e.g., TP420) are used in petrochemical refineries for tubing that handles moderate levels of corrosion and high pressure in process systems.
Furnace tubes: TP446, with its excellent high-temperature properties, is used in furnaces where both corrosion and thermal resistance are crucial.
4. Power Generation
Nuclear power plants: Ferritic stainless steel tubing is often used in nuclear power plants for heat transfer applications because of its corrosion resistance and performance in highly corrosive environments.
Steam turbine components: Strong and tough martensitic grades like TP410 are used for steam turbine components, including blades and high-pressure systems.
5. Food Processing Equipment
Food-grade tubing: Ferritic stainless steel tubes are used in food processing equipment for their corrosion resistance and non-contaminating properties when exposed to food-grade chemicals or cleaning agents.
6. Pulp and Paper Industry
Bleaching and digesting equipment: Martensitic stainless steel tubing is used in bleaching and digesting systems due to its resistance to corrosive chemicals and ability to handle high temperatures and pressure.
7. Water Treatment Systems
Tubing for desalination plants: Ferritic stainless steel tubing is used in desalination equipment, where its corrosion resistance is required for handling seawater or brackish water in high-salinity environments.
