The reversing valve is faulty

The fault of the reversing valve is: the valve cannot be reversed or the reversing action is slow, gas leakage, and the electromagnetic pilot valve is faulty。

(1) The reversing valve can not be reversed or the reversing action is slow, generally due to poor lubrication, the spring is stuck or damaged, oil or impurities stuck in the sliding part and other reasons caused。In this regard, the oil mist should first check whether the work is normal;Whether the viscosity of the lubricating oil is appropriate。If necessary, the lubricating oil should be replaced, the sliding part of the reversing valve should be cleaned, or the spring and reversing valve should be replaced。

(2) After the reversing valve is used for a long time, it is easy to appear the phenomenon of spool seal wear, valve stem and seat damage, resulting in gas leakage in the valve, slow action of the valve or normal reversing and other faults。At this time, the sealing ring, stem and seat should be replaced, or the reversing valve should be replaced。

(3) If the inlet and outlet of the solenoid pilot valve are blocked by debris such as mud, the closure is not strict, the active iron core is stuck, the circuit is faulty, etc., which can lead to the normal reversal of the reversing valve。For the first three cases, the sludge and impurities on the pilot valve and the movable core should be cleaned。The circuit fault is generally divided into control circuit fault and electromagnetic coil fault two categories。Before checking the circuit fault, the manual knob of the reversing valve should be turned several times to see whether the reversing valve can reverse normally under the rated air pressure. If it can reverse normally, the circuit is faulty。When checking, the instrument can measure the voltage of the electromagnetic coil to see whether the rated voltage is reached, if the voltage is too low, the power supply in the control circuit and the associated travel switch circuit should be further checked。If the reversing valve cannot be reversed normally under the rated voltage, check whether the connector (plug) of the electromagnetic coil is loose or the contact is not real。The method is to unplug and measure the resistance value of the coil (generally between several hundred ohms and several thousand ohms), if the resistance value is too large or too small, indicating that the electromagnetic coil has been damaged and should be replaced。

Component failure

The main faults of pneumatic auxiliary components are: oil mist failure, automatic blowdown failure, muffler failure and so on。

(1) The faults of the oil mist are: the adjustment amount of the regulating needle is too small, the oil circuit is blocked, the pipeline leaks, etc., will make the liquid oil droplets cannot be atomized。In this regard, the blockage and air leakage should be treated in time, and the amount of dripping should be adjusted to reach about 5 drops /min。In normal use, the oil level in the oil cup should be kept within the upper and lower limits。The water deposited at the bottom of the oil cup should be eliminated in time。