This European Standard specil7esThe dimensions and marking of IBC (inside boltenvelope gaskets for use with flanges complying with prEN 1759-1:2000,prEN 1759-4:1997 for Class 150 and Class 300 for nominal sizes DN 15 and DN 600.circle) non-metallic PTFE prEN 1759一:1994 and
EN 12560-3:2001 history
2001EN 12560-3:2001 Flanges and their joints - Gaskets for Class-designated flanges - Part 3: Non-metallic PTFE envelope gaskets