Welding Neck Flanges

Dimensions Weld Neck Flanges & Stud Bolts ASME B16.5

Notes:

DIMENSIONAL TOLERANCES OF WELD NECK FLANGES ASME B16.5

Outside Diameter (Note 1)

≤24
1.6 mm (0.06 in)
>24
∓3.2 mm (∓0.12 in)

Diameter Hub at Base

≤24
1.6 mm (0.06 in)
>24
∓3.2 mm (∓0.12 in)

Inside Diameter

≤10
∓0.8 mm (∓0.03 in)
12 thru 18
1.6 mm (0.06 in)
≥20
+3.2 mm / -1.6 mm
(∓0.12 in / -0.06 in)

Diameter Hub at Point of Welding

≤5
+2.4 mm / -0.8 mm
(∓0.09 in / -0.03 in)
≥6
+4.0 mm / -0.8 mm
(+0.15 in / -0.03 in)

Drilling

Bolt Circle
1.6 mm (0.06 in)
Bolt Hole Spacing
∓0.8 mm (∓0.03 in)

Eccentricity Bolt Circle

≤2½
0.8 mm max (0.03 in max)
≥3
1.6 mm max (0.06 in max)

Thickness

≤18
+3.2 mm / -0 (+0.12 in / -0)
≥20
+4.8 mm / -0 (+0.18 in / -0)

Length thru Hub

≤10
1.6 mm (0.06 in)
≥12
∓3.2 mm (∓0.12 in)

Diameter Contact Face

1.6 mm RF (0.06 in)
∓0.8 mm (∓0.03 in)
6.35 mm RF (0.25 in)
∓0.4 mm (∓0.01 in)

Tongue & Groove
∓0.4 mm (∓0.01 in)
Male-Female
∓0.4 mm (∓0.01 in)

1 mm (0.03 in)
2 mm (0.07 in)
6 mm (0.23 in)

(NOTE 1) Tolerances not listed in ASME B16.5-2013