Duplex Steel S31803/S32205 Flanges, which are used to nickel to maintain an austenitic composition at lower temperatures. Duplex Steel S31803 Slip On Flanges is austenitic stainless steels with superior corrosion resistance to stainless steel 317. These Duplex Steel S31803 Threaded Flanges is suitable for welding because it has carbon content lower than 301 to 303 series alloys to avoid carbide precipitation in welding applications. Equipment in the chemical, food, paper, mining, and pharmaceutical and petroleum industries often includes Duplex Steel S31803 Weld Neck Flanges.