Pneumatic valve flange hard seal butterfly performance difference

flange hard seal butterfly major parts of the pneumatic valve pneumatic valve material:
pneumatic valve, cast steel, stainless steel, nickel chromium molybdenum titanium steel
pneumatic valve plate: stainless steel, nickel chromium molybdenum titanium steel
pneumatic valve stem: Cr, stainless steel, nickel chromium molybdenum titanium steel
packing: fluorine plastic, flexible graphite
flange with a standard hard seal butterfly pneumatic valve:
flange connection: GB -, GB.
- GB structure length: GB -
pressure test: GB/T -
drive mode: manual, worm transmission, pneumatic, electric
flange hard seal butterfly pneumatic valve performance specification:
DN nominal diameter (mm: ~
nominal pressure PN (MPa:. ~., Lb, K