Dimensions of Non-Metallic Flat Gaskets ASME B16.21 to be used with Raised Face flanges ASME B16.47 series A

Cross-section Non-metallic flat gasket
bg_gasket_fl_a

Class 150 to 600NPS 26 to 60
NPS d1 d2
Class 150 Class 300 Class 400 Class 600
26 660 775 835 832 867
28 711 832 899 892 914
30 762 883 953 946 972
32 813 940 1006 1003 1022
34 864 991 1057 1054 1073
36 914 1048 1118 1118 1130
38 965 1111 1054 1073 1105
40 1016 1162 1114 1127 1156
42 1067 1219 1165 1178 1219
44 1118 1276 1219 1232 1270
46 1168 1327 1273 1289 1327
48 1219 1384 1324 1346 1391
50 1270 1435 1378 1403 1448
52 1321 1492 1429 1454 1499
54 1372 1549 1492 1518 1556
56 1422 1607 1543 1568 1613
58 1473 1664 1594 1619 1664
60 1524 1715 1645 1683 1721
NPS d1 Class 150 Class 300 Class 400 Class 600
d2

General notes:

  • Dimensions are in millimeters unless otherwise indicated.
  • d2 = Outside diameter.
  • Dimensional tolerances outside diameter: +0 / -3.0 mm.
  • Dimensional tolerances inside diameter: ± 3.0 mm.
  • Thickness (t) specified by customer.