Supply ASTM A182 Gr F347 weld neck flanges to our Russian customer
Hebei Haihao Group has finished an order of ASTM A182 Gr F347 weld neck flange(WN flange) order from Russia. Thus let’s learn more about this material. Grade 347 is an austenitic steel alloy with the addition of a stabilizing element i.e. Niobium. Niobium, when added to stainless steel alloys has a strengthening effect on steels. Niobium along with chromium is a reason why the A182 Grade F347 WN RF Flange can be used for high temperature service. One of the main advantages of this alloy is its excellent resistance to intergranular corrosion after the flange has been exposed to temperatures in the chromium carbide precipitation range. The temperature in the chromium carbide precipitation falls in between the range of 800 to 1500°F. Apart from being useful in high temperature applications, the ASTM A182 F347 Flanges does not compromise its good mechanical properties such as its higher creep and stress rupture. In fact, the properties of grade UNS S34700 Slip On Flange outperform those of Alloy 304 as well as Alloy 304L.
Hence, these flanges are considered for applications where sensitization and intergranular corrosion have been dubbed as major concerns. The alloy is suited to be used in aqueous and low temperature environments due to its ability to resist intergranular attack. Since this particular alloy grade demonstrates good resistance to polythionic acid stress related corrosion cracking, therefore the 347 Stainless Steel Flanges is a useful a material for use around reactor plants. Austenitic grade 347 is essentially a non-magnetic stainless steel alloy in the annealed condition. The alloy can only be hardened if it undergoes a cold working process.