Metric 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	33.3	36.6	38.1	85.9	NA
2	NA	NA	42.9	44.5	46.0	81.0	NA
2-1/2	NA	NA	46.0	49.3	50.8	96.8	NA
3	127.0	127.0	46.0	49.3	50.8	96.8	47.8
4	127.0	177.8	52.3	55.6	57.2	115.8	53.8
5	127.0	190.5	55.6	63.5	65.0	147.6	NA
6	127.0	203.2	55.6	69.9	71.4	147.6	57.2
8	152.4	215.9	60.5	71.4	74.7	133.4	63.5
10	203.2	381.0	68.3	76.2	79.2	158.8	71.4
12	203.2	381.0	77.7	82.6	85.9	165.1	81.0
14	203.2	406.4	77.7	91.9	95.3	177.8	91.9
16	203.2	406.4	79.2	101.6	104.6	177.8	101.6
18	203.2	406.4	101.6	114.3	117.3	203.2	114.3
20	203.2	457.2	111.3	127.0	130.0	215.9	127.0
24	203.2	457.2	NA	153.9	157.2	254.0	153.9
30	304.8	558.8	NA	165.1	NA	NA	NA
36	304.8	558.8	NA	201.2	NA	NA	NA
42	304.8	609.6	NA	251.0	NA	NA	NA
48	381.0	660.4	NA	276.4	NA	NA	NA
54	381.0	711.2	NA	NA	NA	NA	NA
60	381.0	762.0	NA	NA	NA	NA	NA
66	457.2	863.6	NA	NA	NA	NA	NA
72	457.2	914.4	NA	NA	NA	NA	NA

NPS Valve Size	A : Face to Face Lug and Wafer : Offset Seat
3	47.8
4	53.8
6	58.7
8	73.2
10	82.6
12	91.9
14	117.3
16	133.4
18	149.4
20	158.8
24	180.8
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	53.8
4	63.5
6	77.7
8	101.6
10	117.3
12	139.7
14	155.4
16	177.8
18	200.2
20	215.9
24	231.9
NPS Valve Size	A : Face to Face Lug and Wafer : Offset Seat

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