This standard specifies the type, size and technical requirements for flexible graphite composite gaskets for steel pipe flanges (American system). This standard is applicable to flexible graphite composite gaskets for raised-face steel pipe flanges with nominal pressure PN of 2.0MPa (Class 150) ~ 11.0MPa (Class600) specified in HG 20615.
HG 20629-1997 history
2009HG/T 20627-2009 Non-metallic flat gaskets for use with steel pipe flanges(Class designated)
HG 20629-1997 Flexible graphite composite gaskets for steel pipe flanges (American system) was changed to HG/T 20627-2009 Non-metallic flat gaskets for use with steel pipe flanges(Class designated).