Manufacturer of STAINLESS STEEL SEAMLESS PIPES & TUBES - SS Seamless Pipe, SS 304 Seamless Pipe, SS 304L Seamless Pipe and SS 304H Seamless Pipe offered by Trychem Metal And Alloys, Mumbai, Maharashtra. Seamless Pipe McMaster-CarrPipe size is an industry designation, not the actual size. Typically used with standard-wall and low-pressure stainless steel unthreaded pipe fittings. Thick-Wall Stainless Steel Unthreaded Pipe. The addition of molybdenum gives 316 stainless steel excellent corrosion resistance. Seamless Tube Penn StainlessPenn Stainless Products supplies stainless steel seamless tube per ASTM A 213, ASTM A 269 and ASTM A 511. We supply common grades of stainless steel such as 304/304L and 316/316L in standard tube sizes and wall thicknesses. We can also supply nickel alloys.