Diameter Nominal DN (mm)	Nominal Pipe Size NPS (inches)	Outside diameter (OD) inches (mm)
6	1/3	0.405 in (10.29 mm)
8	1/4	0.540 in (13.72 mm)
10	3/8	0.675 in (17.15 mm)
15	1/2	0.840 in (21.34 mm)
20	3/4	1.050 in (26.67 mm)
25	1	1.315 in (33.40 mm)
32	1 1/4	1.660 in (42.16 mm)
40	1 1/2	1.900 in (48.26 mm)
50	2	2.375 in (60.33 mm)
65	2 1/2	2.875 in (73.02 mm)
80	3	3.500 in (88.90 mm)
100	4	4.500 in (114.30 mm)
150	6	6.625 in (168.27 mm)
200	8	8.625 in (219.08 mm)
250	10	10.75 in (273.05 mm)

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