Common Pneumatic Cylinder Failures And Solutions

Common

1. The cylinder is faulty

Due to improper cylinder assembly and long-term use, pneumatic actuator +(cylinder) is prone to internal and external leakage, insufficient output force and uneven action, poor buffering effect, piston rod + and cylinder head * damage and other failure phenomena.

(1) The internal and external leakage of the cylinder is generally caused by eccentric piston rod installation, insufficient supply of lubricating oil, wear or damage of the sealing ring and the sealing ring, impurities in the cylinder and the piston rod are scarred.

Therefore, when the cylinder appears internal and external leakage, the center of the piston rod should be re-adjusted to ensure the coaxial degree of the piston rod and the cylinder; It is necessary to check regularly whether the oil mist + works reliably to ensure that the actuator is well lubricated; When the sealing ring and sealing ring wear or damage ring, it must be replaced in time; If there are impurities in the cylinder, it should be removed in time; Piston rod should be replaced when there is a scar.

(2) The insufficient output force and unstable action of the cylinder are generally caused by the piston or piston rod being stuck, poor lubrication, insufficient gas supply or condensate and impurities in the cylinder. In this regard, the center of the piston rod should be adjusted: check whether the work of the oil mist is reliable; Whether the gas supply line is blocked. When there is condensate and impurities in the cylinder memory, it should be removed in time.

(3) The buffer effect of the cylinder is poor, generally due to the wear of the buffer seal ring or the damage of the adjustment screw. At this time, the sealing ring and adjusting screws should be replaced.

(4) The piston rod and cylinder head of the cylinder are damaged, generally due to the piston rod installation eccentric or the buffer mechanism does not work. In this regard, the central position of the piston rod should be adjusted; Replace the buffer seal or adjusting screw.

2. The reversing valve is faulty

The fault of the reversing valve is: the valve can not reverse or the reversing action is slow, the gas leakage, the electric 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 valve should be replaced.

(2) After a long time of use, the reversing valve is prone to wear the spool seal ring, valve stem and seat damage. Causes gas leakage in the valve, slow operation of the valve or can not be reversed normally. 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 can be reversed normally under the rated air pressure. If it can be changed normally, the circuit is faulty. When checking, the instrument can measure the voltage of the electromagnetic line to see whether the rated voltage is reached, if the voltage is too low, should further check the power supply in the control circuit and the associated stroke switch circuit if the reversing valve can not be reversed normally under the rated voltage, you should 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, if the resistance value is too large or too small, indicating that the electromagnetic wire has been damaged and should be replaced.

3. The pneumatic auxiliary component is faulty

The main faults of pneumatic auxiliary components are: oil mist failure, automatic blowdown device + 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.

(2) The oil and water in the automatic drainer sometimes cannot be automatically excluded, especially in the case of low winter temperatures. At this point, it should be removed and inspected and cleaned.

(3) When the muffler on the reversing valve is too dirty or blocked, it will also affect the sensitivity and reversing time of the reversing valve, so it should be cleaned frequently