347 is a very stable stainless steel. In the temperature reached 427-816 ° C, chromium carbide precipitation conditions, still able to maintain good resistance to intergranular corrosion. Since the addition of titanium in the composition, in the case of chromium carbide formation, 347 alloy can still maintain stability.
347 stainless steel because of its excellent mechanical properties, work in high temperature environment is very advantageous. Compared with 304, 347 has better ductility and resistance to stress fracture.
1. Production specifications (mm): Ø6 × 1 ~ 830 × 20 (can be customized according to customer requirements)
2. Finished product length (m): 5-7 (can be customized according to customer requirements), some up to 28m
3. Product material: 347 (0Cr18Ni11Nb)
4. Theoretical weight (kg / m): Cr-Ni austenitic stainless steel W = 0.02491S (D-S)
5. Implementation criteria:
GB / T14975-2002 GB / T14976-2002 GB / T13296-2007
American Standard: ASTM A312 / A312M ASTM A269 / 269M ASTMA213 / 213A
German standard: DIN2462
Japanese standard: JIS G3463
347 (0Cr18Ni11Nb) stainless steel seamless pipe
1, chemical analysis:
2, hydraulic test:
The stainless steel seamless pipe by the root of the hydraulic pressure test, the specified pressure value, to maintain no less than 5 seconds. Steel pipe shall not be leaking or leakage, the conventional supply of water pressure test for the P = 2SR / D (maximum no more than 20MPa).
3, corrosion resistance:
In applications requiring better resistance to general corrosion and point corrosion, the 347 contains only 2-3% molybdenum, better than 304.
4, process performance test:
Flattening test, tensile test, flaring test, hardness test, metallographic test, nondestructive testing (including eddy current testing and ultrasonic testing).
Applicable to large boiler heat exchanger pipes, steam pipes, petrochemical heat exchanger pipe fittings; can also be used as resistant to corrosion materials. A variety of inorganic acids, organic acids ﹑ alkali ﹑ salt has a good corrosion resistance and pitting resistance, high temperature has a good creep strength
347 (0Cr18Ni11Nb) stainless steel seamless pipe precautions
1. Regardless of the corrosion, stainless steel in the processing and use of the process, to keep its surface clean.
2. Light industry, the need for maintenance is relatively small, only the shelter area sometimes need to use pressurized water cleaning. Heavy industry is recommended to regularly clean, remove the accumulation of dust, these dust may eventually cause corrosion and damage the surface appearance of stainless steel.
3. Sturdy stains and precipitates can be scrubbed with a scouring agent and a fiber brush, sponge, and stainless steel velvet. Stainless steel velvet will leave a permanent scratch on a smooth stainless steel surface. Many stainless steel should be regularly cleaned and disinfected. The equipment is usually cleaned with a special caustic soda, an organic solvent, an acidic solution such as phosphoric acid or sulfuric acid. Strong reducing acids such as hydrofluoric acid or hydrochloric acid may cause damage to stainless steel. After rinsing the solution, rinse the stainless steel thoroughly with water.