Weld neck flanges are a flanges with a heavy welding neck which is hot formed from a circular section of steel plate having a small co-axial hole in the center. Weld Neck Flanges are available with following specifications :

Stainless Steel : ASTM A 182, A 240
Grade : F 304, 304L, 304H, 316, 316L, 316Ti, 310, 310S, 321, 321H, 317, 347, 347H, 904L, Duplex stainless steel UNS S31803, 2205, Super Duplex stainless steel UNS S32750
Carbon Steel : ASTM A 105, ASTM A 181
Alloy Steel : ASTM A 182, GR F1, F11, F22, F5, F9, F91
Nickel Alloys : Monel 400 & 500, Inconel 600 & 625, Incolloy 800, 825, Hastelloy C22, C276
Copper Alloys : Copper, Brass & Gunmetal
Size : 1/8" NB TO 48" NB
Class : 150, 300, 400 , 600, 900, 1500 & 2500
ANSI : ANSI B16.5, ANSI B16.47, MSS SP44, ANSI