Building electric: automatic pneumatic valve common fault analysis

fault, one of the pneumatic valve. The reasons are:
(1) the control channel is sundry jam ( Channel small, easy to jam;
(2) piston for rust stains card at the highest position; Is the upper bearing, but can't move down, can't open the main.
so, piston vacuum pneumatic valve must be installed before the filter; For new installations or stop using the reduced pressure pneumatic valve for a long time, be sure to disassemble and clean. The pass-through
the second failure, pneumatic valve, decompression effect. The reasons are:
(1) the piston at a particular location ( Not top stuck;
(2) the main pneumatic valve pneumatic valve guide hole in cylinder set a handle position ( Is not a closed position stuck;
(3) the lower main pneumatic valve pneumatic disc spring fracture or failure;
(4) pulse pneumatic valve pneumatic valve handle in one pneumatic valve seat hole position ( Is not a closed position and make the piston is always affected by pressure;
5. The main pneumatic disc and the main pneumatic seat, between the two sealing surface dirt stuck or Nick;
6 diaphragm failure due to fatigue or damage.
for vacuum pneumatic valve, especially emphasize regular inspection. If found dirt, rust stains will remove in time; Piston ring damage should be updated; A spring failure need available; If not closed on sealing surface, should be reground; Diaphragm is ineffective to replace; Confirmed by the use of pneumatic valve handle coarser, application of sand paper burnish.