Weld-Neck Flange

Weld-Neck Flange

Kobs India are major Manufacturers, Exporters & Suppliers of Weld Neck Flanges ASME B16.5 worldwide.

304/304L Weld Neck Flanges (WNRF), 310/310S Weld Neck Flanges (WNRF), 316/316L Weld Neck Flanges , 317/317L Weld Neck Flanges (WNRF), 321/321H Weld Neck Flanges, 347/347H Weld Neck Flanges, 446 Weld Neck Flanges.

Alloy Steel, Alloy 20, Carbon Steel, Copper Nickel Alloy, Duplex steel, Hastelloy & Inconel Weld Neck Flanges, Monel, Stainless Steel, Titanium.

Weld Neck Flange is designed in such a way that it can be  joined with a piping system by Butt Welding method. It is relatively expensive because of its long neck, but it is mostly preferred for high stress applications. The neck, or the hub transmits stresses to the base of the hub to the wall thickness of the Butt weld, that provide important reinforcement of the flange. The bore of the flange matches the bore of the pipe, hence reducing turbulence & erosion.


Material of ConstructionStandard Grades
Stainless Steel Weld Neck Flanges ASTM A182, A240
201, 202, F 304, 304L, 304H, 316, 316Ti, 316H, 316L, 316LN, 309S, 309H, 310S, 310H, 317, 317L, 321, 321H, 347, 347H, 904L
Carbon Steel Weld Neck Flanges ASTM A105 Gr. F70,65,60,56,52,46,42
Alloy Steel
Weld Neck Flanges
ASTM A182 F1, F5, F9, F11, F22, F91   
Nickel Alloy Weld Neck Flanges ASTM SB472, SB564, SB162,
SB160
Monel 500 (UNS No. N05500), Nickel 200 (UNS No. N02200), Alloy 20 (UNS No. N08020), Inconel 800 (UNS No. N08800), Inconel 825 (UNS No. N08825), Nickel 201 (UNS No. N02201), Monel 400 (UNS No. N04400), Inconel 601 (UNS No. N06601), Hastelloy C 276 (UNS No. N10276), Inconel 600 (UNS No. N06600), Inconel 625 (UNS No. N06625)
Copper Alloys Weld Neck Flanges ASTM SB151, SB152, SB 61, SB 62  UNS No. C 71500 (Cu-Ni 70/30), C 70600 (Cu-Ni 90/10), UNS No. C 10100, 10200, 10300, 10800, 12000, 12200.  
Low Temperature Carbon Steel Weld Neck Flanges ASTM A350 LF3, LF2
Duplex Steel Weld Neck Flanges ASTM A182, A240 UNS F 60, F 61, F 55, F 53, F51, F 45, F 44    

 

Dimensional Tolerances of Welding Neck Flanges ASME 16.5 : 

 

Outside Diameter
≤ 24 = 1.6 mm | > 24 = ± 3.2 mm
Inside Diameter
≤ 10 = ± 0.8 mm | 12 thru 18 = 1.6 mm | ≥ 20 = + 3.2 mm / - 1.6 mm
Diameter of Contact Face
1.6 mm Raised Face = ± 0.8 mm
6.35 mm Raised Face, Tongue & Groove / Male-Female = ± 0.4 mm
Diameter of Hub at Base
≤ 24 = 1.6 mm | > 24 = ± 3.2 mm
Diameter of Hub at Point of Welding
≤ 5 = + 2.4 mm / - 0.8 mm | ≥ 6 = + 4.0 mm / - 0.8 mm
Drilling
Bolt Circle = 1.6 mm | Bolt Hole Spacing = ± 0.8 mm
Eccentricity of Bolt Circle with Respect to Facing
≤ 2½ = 0.8 mm max. | ≥ 3 = 1.6 mm max
Thickness
≤ 18 = + 3.2 mm / - 0 | ≥ 20 = + 4.8 mm / - 0
Length thru Hub
≤ 10 = 1.6 mm | ≥ 12 = ± 3.2 mm