Dimensions of Non-Metallic Flat Gaskets ASME B16.21
to be used with Raised Face flanges ASME B16.5
Non-metallic flat gasket
Class 150 to 900    NPS 1/2 to 24

General notes:

  • Dimensions are in millimeters unless otherwise indicated.
  • d1 = Inside diameter.
  • d2 = Outside diameter.
  • Dimensional tolerances outside diameter NPS 12 and smaller: +0 / -1.5 mm.
  • Dimensional tolerances outside diameter NPS 14 and larger: +0 / -3.0 mm.
  • Dimensional tolerances inside diameter NPS 12 and smaller: ± 1.5 mm.
  • Dimensional tolerances inside diameter NPS 14 and larger: ± 3.0 mm.
  • Thickness (t) specified by customer.

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