Stainless Steel Pipe Fittings

Weld Neck Flanges (WN Flanges) By yaang.com

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Weld Neck Flanges (WN Flanges) By yaang.com

The Welding Neck Flanges (WN Flanges) is normally referred to as the high hub flange. It is designed to transfer stresses to the pipe, thereby reducing high stress concentrations at the base of the flange. The welding neck flange is the best designed butt-welded flange of those currently available becuase of its inherent structural value. It is expensive because of the design.

Weld-Neck flanges or welding-neck flanges can be differentiated from all other types of flange by their long tapered hub. In addition, there is also a gentle transition of thickness in the region of the butt weld that joins them to pipe or a fitting. Weld-Neck flanges or welding-neck flanges are best suited for severe service conditions, whether loading conditions are substantially constant or fluctuate between wide limits.

Weld Neck Flanges (WN Flanges) are flanges with the wall thickness of the flange having the same dimensions of the matching pipe, the lighter the pipe is, the larger the bore, conversely, the heavier the pipe, the smaller the bore, they are normally used for high pressure, cold or hot temperature.

The various types of steel weld neck flanges (wn flanges):

  • Weld Neck Flat Face Flanges
  • Raised Face Weld Neck Flanges
  • Long Neck Weld Flanges

Standards, Dimensions & Weight

  • ASME B16.5 Class 300 WN Flanges
  • ASME B16.5 Class 600 WN Flanges
  • ASME B16.47 B 605 C 600 WN Flanges
  • ASME B16.47 B 605 C 900 WN Flanges
  • BS 3293 Class 150 WN Flanges
  • BS 3293 Class 300 WN Flanges
  • BS 3293 Class 600 WN Flanges
  • DIN 2631 PN 6 WN Flanges
  • DIN 2632 PN 10 WN Flanges
  • DIN 2633 PN 16 WN Flanges
  • DIN 2634 PN 25 WN Flanges
  • DIN 2635 PN40 WN Flanges
  • ASME B16.5 Class 150 WN Flanges
  • ASME B16.5 Class 900 WN Flanges
  • ASME B16.5 Class 1500 WN Flanges
  • ASME B16.5 Class 2500 WN Flanges
  • ASME B16.47 A SP-44 C 150 WN Flanges
  • ASME B16.47 A SP-44 C 300 WN Flanges
  • ASME B16.47 A SP-44 C 600 WN Flanges
  • ASME B16.47 A SP-44 C 900 WN Flanges
  • ASME B16.47 B 605 C 75 WN Flanges
  • ASME B16.47 B 605 C 150 WN Flanges
  • ASME B16.47 B 605 C 300 WN Flanges

Meterial & Standard for weld neck flanges (wn flanges):

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 #.

Standard ANSI
ANSI B16.5, ANSI B16.47, MSS SP44, ANSI B16.36, ANSI B16.48

DIN
DIN2527, DIN2566, DIN2573, DIN2576, DIN2641, DIN2642, DIN2655, DIN2656,

DIN2627, DIN2628, DIN2629, DIN 2631, DIN2632, DIN2633, DIN2634, DIN2635,

DIN2636, DIN2637, DIN2638, DIN2673

B.S
BS4504 , BS4504, BS1560, BS10

Series A 150,300 Weld Neck Flanges
400, 600 & 900 Weld Neck Flanges

Size: 1/2” to 60”, DN 12mm to DN 1500mm
Pressure class: Class 150 to Class 2,500, PN 2.5 to PN 250
Facing: RF / RTJ

Dimensional Tolerances of Weld Neck Flanges (WN Flanges) ASME B16.5

Dimensions are in millimeters unless otherwise indicated.

OUTSIDE DIAMETER

≤ 24 = 1.6 mm
> 24 = ± 3.2 mm

INSIDE DIAMETER

≤ 10 = ± 0.8 mm
≥ 12 = + 1.6 mm / – 0 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

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.

DIAMETER OF COUNTERBORE

Same as for Inside Diameter

OUTSIDE DIAMETER OF HUB

≤ 12 = + 2.4 mm / – 1.6 mm
≥ 14 = ± 3.2 mm

THICKNESS

≤ 18 = + 3.2 mm / – 0
≥ 20 = + 4.8 mm / – 0

LENGTH THRU HUB

≤ 18 = + 3.2 mm / – 0.8 mm
≥ 20 = + 4.8 mm / – 1.6 mm

Source: Zhejiang Yaang Pipe Industry Co., Limited (www.yaang.com)

Article Categories:
Flange

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