TOBO supplies ASTM A403 WP347H niobium (columbium) stabilized stainless steel equal tees for elevated temperature applications. The higher carbon content combined with niobium stabilization provides superior creep strength and oxidation resistance at temperatures exceeding 540°C (1000°F), making it the preferred choice for high-temperature boiler and pressure vessel piping systems.
| Grade | C (%) | Cr (%) | Ni (%) | Nb+Ta (%) | Key Feature |
|---|---|---|---|---|---|
| WP347 | ≤ 0.08 | 17.0-20.0 | 9.0-13.0 | 10*C min - 1.00 max | Standard niobium stabilized |
| WP347H | 0.04-0.10 | 17.0-20.0 | 9.0-13.0 | 8*C min - 1.00 max | Enhanced high-temperature creep strength |
Power plant superheater and reheater tubing, refinery heater tubes, high-temperature chemical reactors, ethylene cracking furnaces, steam headers, boiler pressure parts, catalytic reformer units, gas turbine exhaust systems
| Nominal Size | DN | OD (inch) | SCH40S Wall | SCH80S Wall | Center to End (inch) |
|---|---|---|---|---|---|
| 1" | 25 | 1.315 | 0.133 | 0.179 | 1.50 |
| 2" | 50 | 2.375 | 0.154 | 0.218 | 2.50 |
| 3" | 80 | 3.500 | 0.216 | 0.300 | 3.38 |
| 4" | 100 | 4.500 | 0.237 | 0.337 | 4.13 |
| 6" | 150 | 6.625 | 0.280 | 0.432 | 5.63 |
| 8" | 200 | 8.625 | 0.322 | 0.500 | 7.00 |
| 10" | 250 | 10.750 | 0.365 | 0.500 | 8.50 |
| 12" | 300 | 12.750 | 0.375 | 0.500 | 10.00 |
| 14" | 350 | 14.000 | 0.375 | 0.500 | 11.00 |
| 16" | 400 | 16.000 | 0.375 | 0.500 | 12.00 |
| 18" | 450 | 18.000 | 0.375 | 0.500 | 13.50 |
| 20" | 500 | 20.000 | 0.375 | 0.500 | 15.00 |
| 24" | 600 | 24.000 | 0.375 | 0.500 | 17.00 |
| 30" | 750 | 30.000 | 0.375 | - | 20.00 |
| 36" | 900 | 36.000 | 0.375 | - | 24.00 |