Excavators often have problems of large or small size. Failure is really a headache! I don't know if the dug ever encountered the excavator's arm dropping. Why does your love machine drop the arm in the end? How to solve the failure of the arm? Now let me briefly introduce some classic cases about dealing with the arm failure of Komatsu excavator, for your reference only.
1. Komatsu PC60-7
Brace up the arm very quickly
Equipment problem:
The problem is "lifting the arm and dropping the arm, but it's dropping very slowly. When the machine is lifted, it falls very fast, and the chain falls to the ground."
Fault analysis:
Maintenance master:
(1) check the oil seal of the big arm and find that the piston is new, and the oil seal has just changed soon.
2. Replace the bucket rod and the big arm. It is found that the spool is normal with the big arm spool, and the big arm still supports up and down very quickly.
The fault point is locked on the cylinder of the big arm. When the cylinder is checked, there is no abnormality with the flashlight, and the hand goes into the middle position and feels a circle. There is a groove on the cylinder, and it is not the end of the two ends.
Inspection and repair:
Maintenance master:
(1) because the grooves are on top of the cylinder, the flashlight can not shine, and the big arm can be lifted back to the tubing and there is no oil in the oil pipe, because the groove is in the middle position so there is no oil.
2. When the car was excavate, it fell very fast, because the piston was usually in the middle of the middle groove in the cylinder, so it fell very badly.
2. Komatsu PC220-7
When the machine moves, the arm has a fast arm speed.
Equipment problem:
Komatsu 220-7 excavator to do the action when the excavator arm drops quickly.
Fault analysis:
1. the field inspection result is 5min, the boom cylinder piston rod moves 10cm, the bucket is used to support the car, the body can not be propped up, and the pump pressure is normal before checking.
2. use the arm arm lever to act as a compound action and barely support the car body. After the fire is extinguished, the sound of hydraulic oil flowing inside the left arm oil cylinder is obviously heard.
3. therefore, we doubt the internal damage of the left arm oil cylinder and the removal of the oil filter core to check the iron chip. Therefore, the left moving arm oil cylinder is decomposed, the cylinder is found, the oil cylinder is replaced, and the arm of the arm is eliminated.
4. again use a shovel to support the car, the rear pump pressure shows 233BAR, the body still can not support, at this time the bucket arm and arm compound action, support the body, check the arm cylinder without arm, analysis that the two arm cylinder has no fault, change the arm cylinder with the rod side overloading overflow valve, so the barrier failure phenomenon is the same.
5. at this time, suspected BOOM1 valve core inner regeneration valve leakage, replace the BOOM1 valve core, support the car, the body can be supported, the rear pump display pressure 335BAR, normal, then decompose the BOOM1 valve core, found regenerated one-way valve fragmentation.
The valve is broken.
Inspection and repair:
Repair worker: repair or replace the new regenerative check valve, troubleshooting trial run.
3. Komatsu PC360-7
The excavator dropped its arm
Equipment problem:
1. Mr. Wang's Excavator in Youyang is a PC360-7 Komatsu excavator, which has worked for 5660 hours.
2. the driver said: the machine has been working well and has not been repaired by the repair shop. During the recent work, there was a breakdown of the excavator's arm.
Fault analysis:
Maintenance master:
1. may be the problem of hydraulic oil
2. may be the problem of oil cylinder oil seal
3. may be the problem of the oil road
4. may be the problem of the safety relief valve
5. may be the problem of the distribution valve
Inspection and repair:
1. check whether the hydraulic oil is dirty or mixed with impurities. Replacement of hydraulic oil
2. check if the oil cylinder and oil seal are damaged? replace
3. check if the safety relief valve is damaged? replace
4. check if distribution valve wear causes internal leakage? Replace the corresponding damage element
5. after replacing the shadow damaged parts, the loading test machine is working normally, and the excavator's arm failure is gone.
4. Komatsu PC80
The machine doesn't work hard when it works.
Equipment problem:
I have a Komatsu 80 excavator recently found that the small arm dropping cylinder is not fast enough to drop things down in 5-6 minutes. What is the reason for this?
Fault analysis:
Maintenance master:
1. The valve core of the pull rod can not be completely repositioned or spool worn. It is recommended to check whether the spool is in position and the other is not in place. At the same time, the corresponding two overflow valves should be checked.
2, the excavator arm maintenance valve is damaged, or the forearm cylinder oil seal is damaged.
Inspection and repair:
After changing the oil seal of the small arm cylinder, the fault is ruled out.
5. Komatsu PC130
When the big arm rises, it goes down automatically.
Equipment problem:
Komatsu PC130 hydraulic excavator will automatically descend when the boom comes up.
Fault analysis:
(1) the back position of the PPC valve of the arm is bad.
The back position of the main control valve spool valve is bad.
Inspection and repair:
1. Start the engine, place the hydraulic locking lever in the locking position, and the boom still slowly rises to the overflow state.
2. The engine stops and the accumulator pressure is released. The boom still can not fall.
After the replacement of the main valve assembly, the failure phenomenon is disappearing.
Troubleshooting conclusion: internal interference of main valve spool. Repair method: replace main valve assembly.
6. Komatsu PC220
The excavator's moving arm shovel is naturally falling
Equipment problem:
A Komatsu excavator appeared the natural drop of the Komatsu excavator's Boom Bucket during operation.
Fault analysis:
Maintenance master:
1, check whether the sealing ring of the boom, bucket and bucket cylinder is damaged, resulting in poor sealing. replace
2, check whether the moving arm, bucket, rod cylinder self damage? replace
3, check the arm to keep the valve failure? replace
4, check whether there is leakage in the main control valve. Repair
Inspection and repair:
After investigation, it is found that the retaining arm of the boom is damaged, and the malfunction is eliminated after replacement.
