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VG300**-OMH0006-A
Trouble shooting
O-ring is swollen.
(6)
Air leakage from the pilot valve air
exhaust port (PE port).
Foreign matter caught in the seat
(2)
Air leakage from the gasket
Insufficient tightening of the bolt
(8)
Excessive lubrication
(5)
Air leakage from the main valve air
exhaust [3(R) port*]
(3)
Incomplete switch of spool valve
(4)
Sealing failure of actuators (such as cylinder)
(7)
Sealing failure
O-ring is worn.
(6)
Lodging of foreign matter.
*For body ported type and N.O.
specification, from 1(P) port.
Perform troubleshooting with higher possibility based on the failure phenomenon.
Problem
Possible causes
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Foreign matter is caught in the pilot valve or spool valve.
(2)
Pilot valve switches. Main valve does
not switch. Or, switching is delayed.
External pilot pressure decreased.
(3)
O-ring is swollen.
(4)
Operation failure
The pilot valve does not switch.
Pilot pressure decreased.
(1)
Countermeasures
