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> ASME ANSI Flange Sizes

ASME ANSI Flange Sizes

(PETERSEN DOES NOT SELL PIPE OR ASME ANSI FLANGES)

Nominal Pipe Size
NPS
(inches)
Class 150
Diameter of
Flange
(inches)
No.
of
Bolts
Diameter of
Bolts
(inches)
Bolt
Circle
(inches)
1/4 3-3/8 4 1/2 2-1/4
1/2 3-1/2 4 1/2 2-3/8
3/4 3-7/8 4 1/2 2-3/4
1 4-1/4 4 1/2 3-1/8
1-1/4 4-5/8 4 1/2 3-1/2
1-1/2 5 4 1/2 3-7/8
2 6 4 5/8 4-3/4
2-1/2 7 4 5/8 5-1/2
3 7-1/2 4 5/8 6
3-1/2 8-1/2 8 5/8 7
4 9 8 5/8 7-1/2
5 10 8 3/4 8-1/2
6 11 8 3/4 9-1/2
8 13-1/2 8 3/4 11-3/4
10 16 12 7/8 14-1/4
12 19 12 7/8 17
14 21 12 1 18-3/4
16 23-1/2 16 1 21-1/4
18 25 16 1-1/8 22-3/4
20 27-1/2 20 1-1/8 25
24 32 20 1-1/4 29-1/2
Nominal Pipe Size
NPS
(inches)
Class 300
Diameter of
Flange
(inches)
No.
of
Bolts
Diameter of
Bolts
(inches)
Bolt
Circle
(inches)
1/4 3-3/8 4 1/2 2-1/4
1/2 3-3/4 4 1/2 2-5/8
3/4 4-5/8 4 5/8 3-1/4
1 4-7/8 4 5/8 3-1/2
1-1/4 5-1/4 4 5/8 3-7/8
1-1/2 6-1/8 4 3/4 4-1/2
2 6-1/2 8 5/8 5
2-1/2 7-1/2 8 3/4 5-7/8
3 8-1/4 8 3/4 6-5/8
3-1/2 9 8 3/4 7-1/4
4 10 8 3/4 7-7/8
5 11 8 3/4 9-1/4
6 12-1/2 12 3/4 10-5/8
8 15 12 7/8 13
10 17-1/2 16 1 15-1/4
12 20-1/2 16 1-1/8 17-3/4
14 23 20 1-1/8 20-1/4
16 25-1/2 20 1-1/4 22-1/2
18 28 24 1-1/4 24-3/4
20 30-1/2 24 1-1/4 27
24 36 24 1-1/2 32
Nominal Pipe Size
NPS
(inches)
Class 400
Diameter of
Flange
(inches)
No.
of
Bolts
Diameter of
Bolts
(inches)
Bolt
Circle
(inches)
1/4 3-3/8 4 1/2 2-1/4
1/2 3-3/4 4 1/2 2-5/8
3/4 4-5/8 4 5/8 3-1/4
1 4-7/8 4 5/8 3-1/2
1-1/4 5-1/4 4 5/8 3-7/8
1-1/2 6-1/8 4 3/4 4-1/2
2 6-1/2 8 5/8 5
2-1/2 7-1/2 8 3/4 5-7/8
3 8-1/4 8 3/4 6-5/8
3-1/2 9 8 7/8 7-1/4
4 10 8 7/8 7-7/8
5 11 8 7/8 9-1/4
6 12-1/2 12 7/8 10-5/8
8 15 12 1 13
10 17-1/2 16 1-1/8 15-1/4
12 20-1/2 16 1-1/4 17-3/4
14 23 20 1-1/4 20-1/4
16 25-1/2 20 1-3/8 22-1/2
18 28 24 1-3/8 24-3/4
20 30-1/2 24 1-1/2 27
24 36 24 1-3/4 32
Nominal Pipe Size
NPS
(inches)
Class 600
Diameter of
Flange
(inches)
No.
of
Bolts
Diameter of
Bolts
(inches)
Bolt
Circle
(inches)
1/4 3-3/8 4 1/2 2-1/4
1/2 3-3/4 4 1/2 2-5/8
3/4 4-5/8 4 5/8 3-1/4
1 4-7/8 4 5/8 3-1/2
1-1/4 5-1/4 4 5/8 3-7/8
1-1/2 6-1/8 4 3/4 4-1/2
2 6-1/2 8 5/8 5
2-1/2 7-1/2 8 3/4 5-7/8
3 8-1/4 8 3/4 6-5/8
3-1/2 9 8 7/8 7-1/4
4 10-3/4 8 7/8 8-1/2
5 13 8 1 10-1/2
6 14 12 1 11-1/2
8 16-1/2 12 1-1/8 13-3/4
10 20 16 1-1/4 17
12 22 20 1-1/4 19-1/4
14 23-3/4 20 1-3/8 20-3/4
16 27 20 1-1/2 23-3/4
18 29-1/4 20 1-5/8 25-3/4
20 32 24 1-5/8 28-1/2
24 37 24 1-7/8 33
Nominal Pipe Size
NPS
(inches)
Class 900
Diameter of
Flange
(inches)
No.
of
Bolts
Diameter of
Bolts
(inches)
Bolt
Circle
(inches)
1/2 4-3/4 4 3/4 3-1/4
3/4 5-1/8 4 3/4 3-1/2
1 5-7/8 4 7/8 4
1-1/4 6-1/4 4 7/8 4-3/8
1-1/2 7 4 1 4-7/8
2 8-1/2 8 7/8 6-1/2
2-1/2 9-5/8 8 1 7-1/2
3 9-1/2 8 7/8 7-1/2
4 11-1/2 8 1-1/8 9-1/4
5 13-3/4 8 1-1/4 11
6 15 12 1-1/8 12-1/2
8 18-1/2 12 1-3/8 15-1/2
10 21-1/2 16 1-3/8 18-1/2
12 24 20 1-3/8 21
14 25-1/4 20 1-1/2 22
16 27-3/4 20 1-5/8 24-1/2
18 31 20 1-7/8 27
20 33-3/4 20 2 29-1/2
24 41 20 2-1/2 35-1/2
Nominal Pipe Size
NPS
(inches)
Class 1500
Diameter of
Flange
(inches)
No.
of
Bolts
Diameter of
Bolts
(inches)
Bolt
Circle
(inches)
1/2 4-3/4 4 3/4 3-1/4
3/4 5-1/8 4 3/4 3-1/2
1 5-7/8 4 7/8 4
1-1/4 6-1/4 4 7/8 4-3/8
1-1/2 7 4 1 4-7/8
2 8-1/2 8 7/8 6-1/2
2-1/2 9-5/8 8 1 7-1/2
3 10-1/2 8 1-1/8 8
4 12-1/4 8 1-1/4 9-1/2
5 14-3/4 8 1-1/2 11-1/2
6 15-1/2 12 1-3/8 12-1/2
8 19 12 1-5/8 15-1/2
10 23 12 1-7/8 19
12 26-1/2 16 2 22-1/2
14 29-1/2 16 2-1/4 25
16 32-1/2 16 2-1/2 27-3/4
18 36 16 2-3/4 30-1/2
20 38-3/4 16 3 32-3/4
24 46 16 3-1/2 39
Nominal Pipe Size
NPS
(inches)
Class 2500
Diameter of
Flange
(inches)
No.
of
Bolts
Diameter of
Bolts
(inches)
Bolt
Circle
(inches)
1/2 5-1/4 4 3/4 3-1/2
3/4 5-1/2 4 3/4 3-3/4
1 6-1/4 4 7/8 4-1/4
1-1/4 7-1/4 4 1 5-1/8
1-1/2 8 4 1-1/8 5-3/4
2 9-1/4 8 1 6-3/4
2-1/2 10-1/2 8 1-1/8 7-3/4
3 12 8 1-1/4 9
4 14 8 1-1/2 10-3/4
5 16-1/2 8 1-3/4 12-3/4
6 19 8 2 14-1/2
8 21-3/4 12 2 17-1/4
10 26-1/2 12 2-1/2 21-1/4
12 30 12 2-3/4 24-3/8