API 6A blind flange working pressure: 2000~20000psi nominal bore:1 13/16"~21 ... , slip on, welding neck, blind, thread, socket weld flangeProcess: free forging, plate cutting, heat treat, machiningSurface Treat: Anti-rust Oil, Paint ... :F304,F304L,F316,F316L,316Ti and etc API 6A blind flange