The switch of pneumatic butterfly valve

songs in pneumatic butterfly valve, pneumatic valve open electricity, why do some adjustment some open power. , this basically is to see how cylinder and pneumatic valve assembly, a state (cylinder One is a piston in the side, one is a piston in the middle) , we just set to open, the edge of the cylinder piston in piston set off in the middle, butterfly pneumatic valve is opened shut other state, if each cylinder and adjustment of pneumatic valve assembly line, that you won't get some adjustment electric pneumatic valve open, some power is opened, there is this problem of cylinder and adjustment of pneumatic valve installed (state of just misplaced If the cylinder air inlet unchanged) , the same pneumatic butterfly valve, if change the air inlet air intake, also can appear open butterfly electric pneumatic valve, open some power. , for single acting pneumatic butterfly valve, general is normally open, normally closed, principle and the same as above