The size diaphragm of pneumatic flange butterfly valves(PN16).

DN	In	pipe diameter	OD of seal surface	PN16 flange
DN	In	pipe diameter	OD of seal surface	OD	PCD	BOLTS&Length		Thinkness
40	1.5	45	85	150	110	4×M16	130	20
50	2	57	100	165	125	4×M16	130	22
65	2.5	73	120	185	145	4×M16	140	24
80	3	89	135	200	160	8×M16	140	24
100	4	108	155	220	180	8×M16	150	26
125	5	113	185	250	210	8×M16	150	28
150	6	159	210	285	240	8×M20	165	28
200	8	219	265	340	295	12×M20	175	30
250	10	273	320	405	355	12×M24	185	32
300	12	325	375	460	410	12×M24	200	32
350	14	377	435	520	470	16×M24	200	34
400	16	426	485	580	525	16×M27	230	38
450	18	480	545	640	585	20×M27	254	42
500	20	530	608	715	650	20×M30	294	48
600	24	630	718	840	770	20×M33	334	50
700	28	720	788	910	840	24×M33	341	50
800	32	820	898	1025	950	24×M36	375	52
900	36	920	998	1125	1050	28×M36		54
1000	40	1020	1110	1255	1170	28×M39		56