ANSI （美國國家標準）的標準管徑

公稱直徑	管道的壁厚系列	管道內徑D/in	管道內徑D/mm
DN50(2in)	40 80 160	2.067 1.939 1.689	52.50 49.25 42.90
DN80(3in)	40 80 160	3.068 2.900 2.624	77.93 73.66 66.70
DN100(4in)	40 80 120 160	4.026 3.826 3.624 3.438	102.26 97.18 92.05 87.33
DN150(6in)	40 80 120 160	6.065 5.761 5.501 5.189	154.1 146.3 139.7 131.8
DN200(8in)	20 30 40 60 80 120	8.125 8.071 7.981 7.813 7.625 7.189	206.4 205.0 202.7 198.5 193.7 182.6
DN250(10in)	30 40 60 80	10.136 10.020 9.750 9.564	257.5 254.5 247.7 242.9
DN300(12in)	30 40 60 80	12.090 11.938 11.626 11.376	307.1 303.2 295.3 289.0
DN350(14in)	30 40 60 80	13.250 13.124 12.814 12.500	336.6 333.4 325.5 317.5
DN400(16in)	30 40 60 80	15.250 15.000 14.688 14.314	387.4 381.0 373.1 363.6
DN450(18in)	20 30 40 60 80	17.376 17.124 16.876 16.500 16.126	441.4 435.0 428.7 419.1 409.6
DN500(20in)	20 30 40 60 80	19.250 19.000 18.814 18.376 17.938	488.9 482.6 477.9 466.8 455.6
DN600(24in)	20 30 40 60 80	23.250 22.876 22.626 22.064 21.564	590.6 581.1 574.7 560.4 547.7