Inch Dimensions of Butterfly Valves as per ASME B16.10

NPS Valve Size	A : Face to Face Flanged : Narrow	A : Face to Face Flanged : Wide	A : Face to Face Lug and Wafer : Narrow	A : Face to Face Lug and Wafer : Wide	A : Face to Face Lug and Wafer : Extra Wide	A : Face to Face Grooved End	A : Face to Face Lug and Wafer : Offset Seat
1-1/2	NA	NA	1.31	1.44	1.50	3.38	NA
2	NA	NA	1.69	1.75	1.81	3.19	NA
2-1/2	NA	NA	1.81	1.94	2.00	3.81	NA
3	5.00	5.00	1.81	1.94	2.00	3.81	1.88
4	5.00	7.00	2.06	2.19	2.25	4.56	2.12
5	5.00	7.50	2.19	2.50	2.56	5.81	NA
6	5.00	8.00	2.19	2.75	2.81	5.81	2.25
8	6.00	8.50	2.38	2.81	2.94	5.25	2.50
10	8.00	15.00	2.69	3.00	3.12	6.25	2.81
12	8.00	15.00	3.06	3.25	3.38	6.50	3.19
14	8.00	16.00	3.06	3.62	3.75	7.00	3.62
16	8.00	16.00	3.12	4.00	4.12	7.00	4.00
18	8.00	16.00	4.00	4.50	4.62	8.00	4.50
20	8.00	18.00	4.38	5.00	5.12	8.50	5.00
24	8.00	18.00	NA	6.06	6.19	10.00	6.06
30	12.00	22.00	NA	6.50	NA	NA	NA
36	12.00	22.00	NA	7.88	NA	NA	NA
42	12.00	24.00	NA	9.88	NA	NA	NA
48	15.00	26.00	NA	10.88	NA	NA	NA
54	15.00	28.00	NA	NA	NA	NA	NA
60	15.00	30.00	NA	NA	NA	NA	NA
66	18.00	34.00	NA	NA	NA	NA	NA
72	18.00	36.00	NA	NA	NA	NA	NA

NPS Valve Size	A : Face to Face Lug and Wafer : Offset Seat
3	1.88
4	2.12
6	2.31
8	2.88
10	3.25
12	3.62
14	4.62
16	5.25
18	5.88
20	6.25
24	7.12
NPS Valve Size	A : Face to Face Lug and Wafer : Offset Seat

NPS Valve Size	A : Face to Face Lug and Wafer : Offset Seat
3	2.12
4	2.50
6	3.06
8	4.00
10	4.62
12	5.50
14	6.12
16	7.00
18	7.88
20	8.50
24	9.13
NPS Valve Size	A : Face to Face Lug and Wafer : Offset Seat

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