The table below provides the gasket dimensions for American Water Works Association flanges of type C207 (steel flanges) and C228 (stainless steel flanges).

NPS | ID | OD | Hole Qty | Hole Size | BCD |
---|---|---|---|---|---|
4 | 4.5 | 9 | 8 | 0.75 | 7.5 |
5 | 5.56 | 10 | 8 | 0.88 | 8.5 |
6 | 6.62 | 11 | 8 | 0.88 | 9.5 |
8 | 8.62 | 13.5 | 8 | 0.88 | 11.75 |
10 | 10.75 | 16 | 12 | 1 | 14.25 |
12 | 12.75 | 19 | 12 | 1 | 17 |
14 | 14 | 21 | 12 | 1.13 | 18.75 |
16 | 16 | 23.5 | 16 | 1.13 | 21.25 |
18 | 18 | 25 | 16 | 1.25 | 22.75 |
20 | 20 | 27.5 | 20 | 1.25 | 25 |
24 | 24 | 32 | 20 | 1.38 | 29.5 |
NPS | ID | OD | Hole Qty | Hole Size | BCD |
---|---|---|---|---|---|
26 | 26 | 34.25 | 24 | 1.38 | 31.75 |
28 | 28 | 36.5 | 28 | 1.38 | 34 |
30 | 30 | 38.75 | 28 | 1.38 | 36 |
32 | 32 | 41.75 | 28 | 1.63 | 38.5 |
34 | 34 | 43.75 | 32 | 1.63 | 40.5 |
36 | 36 | 46 | 32 | 1.63 | 42.75 |
38 | 38 | 48.75 | 32 | 1.63 | 45.25 |
40 | 40 | 50.75 | 36 | 1.63 | 47.25 |
42 | 42 | 53 | 36 | 1.63 | 49.5 |
44 | 44 | 55.25 | 40 | 1.63 | 51.75 |
46 | 46 | 57.25 | 40 | 1.63 | 53.75 |
48 | 48 | 59.5 | 44 | 1.63 | 56 |
50 | 50 | 61.75 | 44 | 1.88 | 58.25 |
52 | 52 | 64 | 44 | 1.88 | 60.5 |
54 | 54 | 66.25 | 44 | 1.88 | 62.75 |
56 | 56 | 68.75 | 48 | 1.88 | 65 |
58 | 58 | 71 | 48 | 1.88 | 67.25 |
60 | 60 | 73 | 52 | 1.88 | 69.25 |
NPS | ID | OD | Hole Qty | Hole Size | BCD |
---|---|---|---|---|---|
66¹ | 66 | 80 | 52 | 1.88 | 76 |
72¹ | 72 | 86.5 | 60 | 1.88 | 82.5 |
84¹ | 84 | 99.75 | 64 | 2.13 | 95.5 |
96¹ | 96 | 113.25 | 68 | 2.38 | 108.5 |
NPS = Nominal Pipe Size
ID = Inner Diameter
OD = Outer Diameter
BCD = Bolt Circle Diameter
General Note:
All dimensions are in inches.
Larger sizes as well as customized sizes can be furnished.
Bolt diameter should be 1/8″ less than the bolt hole size.
¹ For Reference Only:
Sizes NPS 66, 72, 84 and 96 are equal to Taylor-Forge Class 125
Standards:
ASME B16.5 – Pipe flanges and flanged fittings: NPS 4 through 24
ASME B16.47 – Large diameter steel flanges: NPS 26 through NPS 60 standard
No liability or guarantee for the correctness and completeness of the information provided
NPS | ID | OD | Hole Qty | Hole Size | BCD |
---|---|---|---|---|---|
4 | 4.5 | 9 | 8 | 0.75 | 7.5 |
5 | 5.56 | 10 | 8 | 0.88 | 8.5 |
6 | 6.62 | 11 | 8 | 0.88 | 9.5 |
8 | 8.62 | 13.5 | 8 | 0.88 | 11.75 |
10 | 10.75 | 16 | 12 | 1 | 14.25 |
12 | 12.75 | 19 | 12 | 1 | 17 |
14 | 14 | 21 | 12 | 1.13 | 18.75 |
16 | 16 | 23.5 | 16 | 1.13 | 21.25 |
18 | 18 | 25 | 16 | 1.25 | 22.75 |
20 | 20 | 27.5 | 20 | 1.25 | 25 |
24 | 24 | 32 | 20 | 1.38 | 29.5 |
NPS | ID | OD | Hole Qty | Hole Size | BCD |
---|---|---|---|---|---|
26 | 26 | 34.25 | 24 | 1.38 | 31.75 |
28 | 28 | 36.5 | 28 | 1.38 | 34 |
30 | 30 | 38.75 | 28 | 1.38 | 36 |
32 | 32 | 41.75 | 28 | 1.63 | 38.5 |
34 | 34 | 43.75 | 32 | 1.63 | 40.5 |
36 | 36 | 46 | 32 | 1.63 | 42.75 |
38 | 38 | 48.75 | 32 | 1.63 | 45.25 |
40 | 40 | 50.75 | 36 | 1.63 | 47.25 |
42 | 42 | 53 | 36 | 1.63 | 49.5 |
44 | 44 | 55.25 | 40 | 1.63 | 51.75 |
46 | 46 | 57.25 | 40 | 1.63 | 53.75 |
48 | 48 | 59.5 | 44 | 1.63 | 56 |
50 | 50 | 61.75 | 44 | 1.88 | 58.25 |
52 | 52 | 64 | 44 | 1.88 | 60.5 |
54 | 54 | 66.25 | 44 | 1.88 | 62.75 |
56 | 56 | 68.75 | 48 | 1.88 | 65 |
58 | 58 | 71 | 48 | 1.88 | 67.25 |
60 | 60 | 73 | 52 | 1.88 | 69.25 |
NPS | ID | OD | Hole Qty | Hole Size | BCD |
---|---|---|---|---|---|
66¹ | 66 | 80 | 52 | 1.88 | 76 |
72¹ | 72 | 86.5 | 60 | 1.88 | 82.5 |
84¹ | 84 | 99.75 | 64 | 2.13 | 95.5 |
96¹ | 96 | 113.25 | 68 | 2.38 | 108.5 |
NPS = Nominal Pipe Size
ID = Inner Diameter
OD = Outer Diameter
BCD = Bolt Circle Diameter
General Note:
All dimensions are in inches.
Larger sizes as well as customized sizes can be furnished.
Bolt diameter should be 1/8″ less than the bolt hole size.
¹ For Reference Only:
Sizes NPS 66, 72, 84 and 96 are equal to Taylor-Forge Class 125
Standards:
ASME B16.5 – Pipe flanges and flanged fittings: NPS 4 through 24
ASME B16.47 – Large diameter steel flanges: NPS 26 through NPS 60 standard
No liability or guarantee for the correctness and completeness of the information provided