If it cannot rotate in both left and right directions, first check whether the positioning pin of the slewing platform has been pulled out. Pull out the platform locating pin before turning. If the positioning pin of the platform has been pulled out and still cannot rotate left and right, start the machine to fully extend the stick and bucket cylinder, and stop the machine when the bucket is about 1.5m above the ground. Without operating the pilot handle, several people push the bucket along the rotation direction of the platform. At this time, if the platform can rotate at a small angle, it means that the rotation reducer is not damaged, It is other faults that cause the platform to not rotate left and right. If the platform cannot rotate when several people push the bucket, the fault is caused by the damage of the swing reducer. The rotary reducer shall be disassembled for troubleshooting. The platform cannot rotate left and right. If it is not caused by the reducer, the fault shall be analyzed and eliminated according to the following sequence:
1. Check whether the pilot valve core controlling rotation can be pressed in place or blocked. If the rotary pilot valve core cannot be pressed in place, it shall be repaired or replaced; If the pilot valve core is blocked by foreign matters, the foreign matters shall be removed to make the pilot valve core move up and down freely.
2. Check whether the rotary brake valve is intact and whether the rotary brake mechanism is properly adjusted. If the rotary brake valve is damaged or the rotary brake mechanism is improperly adjusted, the rotary reducer is always in the braking state, and the platform cannot rotate left and right. At this time, the rotary brake valve shall be repaired or the rotary brake mechanism shall be reasonably adjusted.
3. Check whether the rotary reversing valve rod of multi-way valve can change direction flexibly. If the reversing is not flexible, it may be caused by the following three reasons:
(1) The return spring of the rotary reversing valve rod is broken;
(2) The rotary reversing valve rod is stuck or stuck by foreign matters;
(3) The pressure entering the pilot control room of the rotary reversing valve rod is small, which is not enough to make the valve rod reverse flexibly.
4. Measure whether the oil inlet pressure of swing motor is normal. If the inlet pressure is always low or no pressure, it may be caused by the following reasons:
(1) The overflow pressure of the corresponding main safety valve is low. At this time, the corresponding main safety valve shall be adjusted to make its pressure reach the specified value; If the main safety valve fails, repair or replace the corresponding main safety valve and adjust the pressure to the specified value.
(2) The overflow pressure of the rotary secondary overflow valve is low. There are the following situations,
①. The rotary secondary overflow valve has good performance, but the pressure adjustment value is low; The overflow pressure shall be adjusted to the specified value.
②. Insufficient tightening torque of Rotary Secondary overflow valve; It shall be tightened to the specified torque.
③. Rotary secondary overflow valve fails; Repair or replace the secondary overflow valve and adjust its overflow pressure according to the specified value.
④. The valve body of the rotary secondary overflow valve is damaged, so that the oil in the high and low pressure chambers is connected; Replace the damaged valve body.
(3) The fit clearance between the rotary control valve rod and the valve body of the multi-way directional valve is too large, and the internal leakage is serious; A single valve stem shall be provided.
5. When there is high pressure at the oil inlet of the swing motor, if the platform still cannot rotate, the maintenance personnel shall touch the motor oil return pipe by hand. If you can't feel the oil flow in the pipe and feel the motor vibration, you can judge that it is the internal damage of the motor. If the maintenance personnel feel that there is oil flow in the hydraulic motor return pipe and the platform still cannot rotate, it may be caused by the following reasons:
(1) The output Journal of the rotary hydraulic motor is broken; The hydraulic motor should be replaced or repaired.
(2) The internal spline of the input shaft of the reducer is sheared; Replace damaged parts.
(3) Since the slewing ring is not greased during long-term use, the slewing ring is clenched; Butter should be added to make it better lubricated.
(4) The slewing ring isolator or steel ball is damaged and clenched; Replace the damaged parts and add lubricating grease.
