The lifting device of the truck crane consists of a power picker and a gear pump.
Generally using compressed air to push the fork to make gear meshing, output power,
When opened in the cab of the Power picker switch, such as the discovery of hydraulic pump power transmission shaft does not rotate, and issued abnormal sound, the cause of the failure is generally:
① air pressure is insufficient;
② Air duct plug;
③ solenoid valve failed.
First of all, to observe the index on the barometer, if the pressure is lower than the working pressure, it is necessary to increase the throttle to improve the pressure; if the pressure is normal, you have to look for the gas valve before and after the air duct whether the rainy season plug, the pipeline has ruptured gas leakage, resulting in the Check the solenoid valve is safe and reliable, if not troubleshooting, should remove the power cylinder, remove the piston rod, replace the piston or O-type sealing ring, and clear the cylinder wall dirt.
When the lifting operation is finished, the power switch is turned off, and the drive shaft of the picker is still rotating to make the hydraulic pump work, generally for the following reasons:
① pressure on the fork of the nut loose;
② the screw on the piston rod is loosened.
The spring and the performance of the piston rod of the ③ are weakened or damaged.
The first is to check the pressure on the fork of the nut is falling off, if the nut is off, the picker cylinder block removed, replace the new lock, fastening nut. If the fork is well fastened on the piston rod, the back cover of the picker cylinder is removed to see if the screw on the piston rod is loose. If the screws loose, should be tightened again, put on the opening pins. Both of the above are intact, push the piston rod with the hand, if the feeling has the empty itinerary, the proof is damaged, must remove the cylinder seat, replace the new spring.