TP 347H / UNS S 34709
Type 347H stainless steel has slightly improved corrosion resistance over type 321 stainless steel in strongly oxidizing environments. Type 347H is stabilized with columbium; it is preferable for aqueous and low temperature environments due to its good resistance to intergranular attack. Both 347H and 321H offer good resistance to polyphonic acid stress corrosion cracking, encountered in oil refineries. The high temperature oxidation resistance of 347 is similar to that of 304 stainless steel. Useful to 1500°C. Maintains good corrosion resistance in applications where the temperature is between 800°F and 1500°F.• Good resistance to intergranular corrosion in the as welded condition.
Main applications: Refinery Heat exchangers, furnaces, boilers in chemical and petrochemical plant.
- Heat Exchanger Tubes
- Boiler Tubes & Pipes
- Line Pipes
- Hydraulic Tubes
- Instrumentation Tubes
- Structural Pipes
- Mechanical Tubes & Pipes
TPS Technitube supplies TP 347H / UNS S 34709 in a big variety of forms incl.:
Seamless Tubes & Pipes
Welded Tubes and Pipes
Buttweld Fittings
Forged Fittings
Flanges and Forgings
Plates, Sheets and Bars
Chemical Composition
| C | = 0.04-0.10 % | S | = 0.030 % max | |
| Si | = 0.75 % max | Ni | = 9.00-13.00 % | |
| Mn | = 2.00 % max | Cr | = 17.00-20.00 % | |
| P | = 0.040 % max | Others | = (Cu + Ta) Ž 10xC, max 1.00% |
Mechanical properties all at room temperature
| Elongation in 2 in or 50 mm, (or 4D), min 40% | |
| YS min | |
| KSI (MPa) | = 30[205] |
| TS min | |
| KSI [MPa] | = 75[515] |
| El. Min | 35 |
Please select your country to contact us
TPS-Technitube Röhrenwerke GmbH
Julius-Saxler-Str. 7 | 54550 Daun/Germany
Tel.: +49 65 92 71 20 | Fax: +49 65 92 1305
www.technistock.de | www.tpsd.de | E-Mail: service@tpsd.de