What are the common faults of Komatsu loader planetary transmission clutch?

Loader is a very common construction machinery and equipment, which is widely used. But this behemoth also has "sick" times, especially when the loader planetary gearbox overtakes the clutch, and there are often some small conditions that affect the normal construction. Here are a few common faults.

1. When low-speed and heavy-load, there is an instantaneous pause.

When the loader is working at low speed and heavy loads, there is a sudden pause of "click", followed by refueling, and the car continues to move forward, which is the most common early manifestation of overtaking clutch failure. As the time of use increases, this phenomenon will appear more and more frequently in the operation, and the downtime will be extended accordingly.

2. The gear is running normally, but the sudden work is weak, and the transmission oil temperature increases.

The loader usually works well and drives normally, but it will suddenly appear weak. During the inspection, it was found that the oil level met the requirements, the oil bottom filter was not blocked, and the variable speed pressure was normal, which indicated that the override clutch had been damaged and failed.

3. The gearbox suddenly made abnormal noises and the speed of the vehicle decreased sharply.

When the loader is driving at a higher speed, it suddenly makes a large mechanical noise in the gearbox, and then the speed of the vehicle decreases sharply as if it is braked, at this time, release the accelerator, stop the car, no need to remove the gear, idle for a while, the abnormal sound disappears, and then step on the accelerator, and the locomotive returns to normal. If this phenomenon occurs from time to time, it is caused by the phenomenon of the roller that surpasses the clutch has a hairpin, and the roller should not be in the working position and is now stuck in the working position, so that the original non-participating in the work of the first-class turbine output gear and the outer ring gear beyond the clutch work intermittently, causing the gear to make a larger impact sound, and at the same time produce a larger braking force.

4. When starting or shifting gears, the locomotive reacts slowly.

In the operation of the loader, the rhythm of the hand feeling is normal when the gear is attached, the gear lever system is not loose, and the reaction of the variable speed pressure and gear shift is also normal, but when starting and shifting, the locomotive sometimes reacts slowly, which is caused by the poor joint between the outer ring gear and the inner ring cam of the overtaking high sealer and the slow locking.

5. There is no difference in speed between gear and I gear.

Some loaders work vigorously at low speed and heavy load, but the oil temperature of the torque converter rises faster, and there is no difference between the speed of gear and 1st gear. This is due to the fact that the roller that overtakes the clutch is stuck in the working position, so that the outer ring gear and the inner ring cam are always in a state of engagement.

Clutch squeak.

Phenomenon: The clutch of the car makes an abnormal noise when it is disengaged or engaged.

Reason: Lack of lubricant in the separating bearing, resulting in dry friction or bearing damage; There is no clearance between the release bearing and the inner end of the release lever; The oil and dust between the separation bearing sleeve and the conduit are seriously greasy or the separation bearing return spring and the pedal return spring are fatigued, broken and fall off, so that the separation bearing returns poorly; The spline hole of the driven disc is loose with its spline shaft; Driven disc shock absorbing springs, annealing, fatigue or breakage; The rivet of the friction plate of the driven disc is loose or the rivet head is exposed; The pin holes of the double plate clutch drive pin and the intermediate pressure plate and pressure plate are worn and empty.

Diagnosis and elimination: slightly press the clutch pedal to make the release bearing contact with the release lever, if there is a "rustling" sound, it is a bearing abnormal sound, if there is still an abnormal sound after refueling, it means that the bearing is worn excessively, loose and damaged, and should be replaced; If there is an intermittent collision sound, it means that there is movement before and after the release bearing, and the return spring of the release bearing should be replaced; Even when the pedal is pressed, if there is a sound when the clutch is just engaged or disengaged, it means that the rivet of the driven disc is loose or exposed, and the driven disc should be replaced.

The car clutch disengagement is not complete.

Phenomenon: When the engine is idling, press the clutch pedal, there is a gear impact sound and it is difficult to hook in, if it is barely hooked, the engine is completely turned off when the clutch pedal is not completely relaxed.

Cause: The clutch pedal free travel is too large; The separation lever is bent and deformed, the bearing is loose, and the bearing axle pin comes out, which makes it difficult to adjust the height of the inner end of the separation lever; The separation lever is improperly adjusted so that the inner end is not in the same plane or the height of the inner end is too low; The spacing screw of the intermediate pressure plate of the double-plate clutch is improperly adjusted, the individual separation spring is fatigued, the height is insufficient or broken, and the intermediate pressure plate is not flexible on the transmission pin or the axial movement in the clutch drive window; The driven disc steel sheet is warped, the friction plate is broken or the rivet is loose; The newly replaced friction plate is too thick or the driven disc is installed incorrectly; driven disc spline hole and transmission first axis spline shaft cassette; The clutch hydraulic control mechanism leaks oil, and there is air or insufficient oil volume; Weakened elastic force of diaphragm springs; The engine mount is worn or damaged, and the engine crankshaft is not the same shaft as the transmission input shaft.

Diagnosis and elimination: check the free stroke of the clutch pedal of the car, adjust it if the free stroke is too large, check whether the oil volume of the liquid storage tank is insufficient or there is air in the pipeline for the hydraulic control mechanism and carry out the necessary elimination; Check the height of the inner end of the separation lever, if the separation lever is too low or not in the same plane, adjust it, otherwise check the reverses of the driven plate, if it is all right, continue to check; Check whether the driven disc is warped and deformed, the rivets fall off, and whether the driven disc is axial motion cassette, if so, replace or repair.

1. When the gear is engaged, it cannot enter the gear smoothly. There are several reasons for this:

1) The pressure valve pressure is too low;

2) The hydraulic pump works poorly and seals poorly;

3) Blockage of hydraulic pipelines;

4) Clutch seal ring is damaged and leaked;

5) The valve stem of the hanging gear is not in place.

2. When the gearbox is changing, the gear cannot be disengaged. There are several reasons for this:

1) The piston ring is inflated;

2) Clutch friction plate burned;

3) Clutch return spring failure or damage;

4) The oil return line is blocked.

3. The gear has been hung up, but the loader is running weakly and can't even walk. There are several reasons for this:

1) The friction plate is seriously worn and the gap is too large;

2) The clutch automatic emptying valve is not tightly sealed, so that the pressure drops;

3) The pipeline of the shift control valve is blocked;

4) The shut-off valve cannot be returned;

5) The positioning spring of the transmission valve is fatigued or broken, and the steel ball jumps;

6) The clutch piston ring and sealing ring are seriously worn, which makes the leakage serious.

4. The manipulation pressure is too low. There are several reasons for this:

1) The oil quantity of the transmission oil pan is insufficient;

2) Oil leakage from the main oil channel;

3) Transmission filter blockage;

4) The steering pump (or hydraulic pump) is damaged, resulting in serious internal leakage;

5) Improper adjustment of the pressure regulator of the gearbox;

6) The spring of the pressure valve fails or breaks.

5. The gearbox automatically disconnects or disobserves. There are several reasons for this:

1) The positioning device of the shift control valve fails, and the main reason for the failure is that the positioning ball is seriously worn or the spring fails;

2) Due to long-term use, the position and length of the shift lever change, and the proportion of the rod is not accurate, which makes the operating position deviate, resulting in dislocation.

Causes of damage to the clutch of Komatsu loaders: When the clutch of the power shift transmission is engaged, the pressure of the hydraulic oil overcomes the spring force to compress the friction plate. As the hydraulic oil pressure increases, the friction plate contacts the metal disc and gradually compresses, allowing the clutch to smoothly transmit the flywheel power to the transmission shaft.

Every time you change gears, the friction plates rub against the steel plates, and the heat generated is dissipated by the coolant. When the friction plate and steel plate become thinner, more hydraulic oil is required in order for them to be fully engaged, the engine must be further accelerated, and the slippage time of the friction plate on the steel plate is also extended, and the resulting frictional heat will be more, which will cause the temperature of the hydraulic oil to increase, and when it reaches a temperature sufficient to change the performance of the seals in the transmission, the transmission will produce internal leakage. Internal leakage, in turn, continues to cause an increase in heat in two ways:

The high-pressure oil leaks through the damaged seal, so that the oil temperature continues to rise; Due to the oil leakage, the hydraulic pump is bound to deliver more oil to ensure the required pressure when engaging the clutch, so that the clutch is fully engaged, which also requires the engine to continue to accelerate, so that the liquid pressure pump produces a larger flow rate. This vicious circle will eventually lead to overheating or burning of the clutch until it is completely closed.