Gasket
Metallic and nonmetallic gasket standards for pipe flanges.
ASME B16.20
ASMEMetallic Gaskets for Pipe Flanges
Metallic gaskets for pipe flanges — spiral-wound, ring-joint (RTJ), and jacketed — dimensioned, colour-coded, and marked to match ASME B16.5 (NPS ½–24) and B16.47 (Series A/B, NPS 26 and larger) flanges across their pressure classes. Published by ASME as a dimensional and identification standard, not a materials-performance spec.
ASME B16.21
ASMENonmetallic Flat Gaskets for Pipe Flanges
Types, sizes, materials, dimensions, tolerances, and markings for nonmetallic flat gaskets (full-face and ring) for pipe flanges.
API 601
APIMetallic Gaskets for Raised-Face Pipe Flanges (Withdrawn)
A withdrawn API specification for double-jacketed and spiral-wound metallic gaskets for raised-face refinery flanges; superseded by ASME B16.20.
EN 1514
ENGaskets for PN-Designated Flanges
Dimensions and types of gaskets for PN-designated (European) flanges, across nonmetallic, spiral-wound, jacketed, and grooved-metal styles.
EN 12560
ENGaskets for Class-Designated Flanges
Dimensions and types of gaskets for Class-designated flanges in the European standards system (the EN counterpart for ASME-Class-style flanges).