400 Series Flange Specs
All dimensions given in inches.
Dimensions and tolerances in accordance with ANSI B16.5.
*1/4 in. raised face included in dimensions Q, Y and YY.
**Bolt hole diameter 1/8 in. larger than bolt diameter.
Nom. Pipe Size O Q* R X No. and** 
Dia of
Bolt Holes		 Bolt 
Circle 
Dia.		 YY* H J Y* B r YV BB C T
½ 3.75 0.56 1.38 1.5 4-0.62 2.62 2.06 0.84
To 

Be

S
p
e
c
i
f
i
e
d

by

P
u
r
c
h
a
s
e
r

 0.88 0.88 0.12 0.88 0.9 0.93 0.62
¾ 4.62 0.62 1.69 1.88 4-0.75 3.25 2.25 1.05 1 1.09 0.12 1 1.11 1.14 0.62
1 4.88 0.69 2 2.12 4-.075 3.5 2.44 1.32 1.06 1.36 0.12 1.06 1.38 1.41 0.69
1¼ 5.25 0.81 2.5 2.5 4-0.75 3.88 2.62 1.66 1.12 1.7 0.19 1.12 1.72 1.75 0.81
1½ 6.12 0.88 2.88 2.75 4-0.88 4.5 2.75 1.9 1.25 1.95 0.25 1.25 1.97 1.99 0.88
2 6.5 1 3.62 3.31 8-0.75 5 2.88 2.38 1.44 2.44 0.31 1.44 2.46 2.5 1.12
2½ 7.5 1.12 4.12 3.94 8-0.88 5.88 3.12 2.88 1.62 2.94 0.31 1.62 2.97 3 1.25
3 8.25 1.25 5 4.62 8-0.88 6.62 3.25 3.5 1.81 3.57 0.38 1.81 3.6 3.63 1.38
3½ 9 1.38 5.5 5.25 8-1.00 7.25 3.38 4 1.94 4.07 0.38 1.94 4.1 4.13 1.56
4 10 1.38 6.19 5.75 8-1.00 7.88 3.5 4.5 2 4.57 0.44 2 4.6 4.63 1.44
5 11 1.5 7.31 7 8-1.00 9.25 4 5.56 2.12 5.66 0.44 2.12 5.69 5.69 1.69
6 12.5 1.62 8.5 8.12 12-1.00 10.62 4.06 6.63 2.25 6.72 0.5 2.25 6.75 6.75 1.81
8 15 1.88 10.62 10.25 12-1.12 13 4.62 8.63 2.69 8.72 0.5 2.69 8.75 8.75 2
10 17.5 2.12 12.75 12.62 16-1.25 15.25 4.88 10.75 2.88 10.88 0.5 4 10.92 10.88 2.19
12 20.5 2.25 15 14.75 16-1.38 17.75 5.38 12.75 3.12 12.88 0.5 4.25 12.92 12.94 2.38
14 23 2.38 16.25 16.75 20-1.38 20.25 5.88 14 3.31 14.14 0.5 4.62 14.18 14.19 2.5
16 25.5 2.5 18.5 19 20-1.50 22.5 6 16 3.69 16.16 0.5 5 16.19 16.19 2.69
18 28 2.62 21 21 24-1.50 24.75 6.5 18 3.88 18.18 0.5 5.38 18.2 18.19 2.75
20 30.5 2.75 23 23.12 24-1.62 27 6.62 20 4 20.2 0.5 5.75 20.25 20.19 2.88
24 36 3 27.25 27.62 24-1.88 32 6.88 24 4.5 24.25 0.5 6.25 24.25 24.19 3.25