????(DN)		ISO/UNE/GB(??)	BS(??)	ASTM/SCH80(??)	JIS(??)
		??	??	??	??
mm	In	mm	mm	mm	mm
10	3/8"	16	17.0	17.1	17.8
15	1/2"	20	21.2	21.3	21.8
20	3/4"	25	26.6	26.7	25.8
25	1"	32	33.4	33.4	31.8
32	1 1/4"	40	42.0	42.2	37.7
40	1 1/2"	50	48.1	48.3	47.7
50	2"	63	60.2	60.3	59.6
65	2 1/2"	75	75.0	73.0	75.6
80	3"	90	88.7	88.9	88.5
100	4"	110	114.1	114.3	113.4
125	5"	140	140.0	141.3	139.2
150	6"	160	168.0	168.3	164.0
200	8"	225	218.8	219.1	214.7