Troubleshooting of hydraulic system of tor0151e scraper

Troubleshooting of hydraulic system of tor0151e scraper

1. Failure of steering hydraulic system

(1) Fault phenomenon.

The common faults of the steering hydraulic system include the failure of the steering hydraulic cylinder, the instability of the system pressure and external leakage.

(2) Troubleshooting.

The main reason why the steering hydraulic cylinder does not act is that there is too little hydraulic oil in the oil tank, and the steering control valve fails; The oil is polluted, and there are sundries in the valve body, which block the oil circuit and wear and corrosion the valve core; The spring is fatigued and broken, and the valve body is deformed during installation, causing the steering valve core to not move; The steering pump gear is seriously worn, or the steering pump transmission is damaged, and the steering pump cannot output pressure oil; The piston seal of the steering hydraulic cylinder is damaged and loses its sealing function; The hydraulic cylinder arm is worn and strained, with grooves and large internal leakage; The oil suction pipe, pressure oil pipe and pipe joint are damaged and leaking oil. When dealing with this fault, first check whether there is no oil or too little oil in the oil tank, and refuel the oil tank according to the actual situation. Check the hydraulic pump and transmission device, check the wear of the gear of the hydraulic pump, and check whether the transmission device is damaged. The hydraulic pump shall be repaired if it is worn, and it shall be replaced in time if it is seriously worn. Dredge the whole oil circuit, clean the steering valve spool and related hydraulic components, polish and repair the worn spool, replace the spring if the spring is tired and broken, replace the piston seal of the steering cylinder if it is damaged, and replace the new part if the hydraulic cylinder is strained.

The main reason for the low pressure of the steering hydraulic system is the failure of the steering pump, and the hydraulic oil output by the hydraulic pump cannot reach the rated pressure. The opening pressure of the safety valve in the steering valve is too low, or the safety valve core is damaged, the oil outlet is normally open, the pipeline components are damaged and leak oil, and the system pressure cannot be established. Check whether the hydraulic pump is normal when handling the fault. If the hydraulic pump is damaged, repair or replace it. The pressure of the steering safety valve is positioned incorrectly. Readjust the pressure of the safety valve to make the pressure reach 15.0mpa. If the safety valve is damaged, it should be replaced in time. If the pipeline element is damaged and leaks oil, replace the O-ring seal and the corresponding pipeline element.

The main reason for the unstable pressure of the steering system is that the hydraulic oil contains air; The oil circuit is immersed in impurities, causing oil pollution; The hydraulic components in the system are unstable. When dealing with the fault, first check the hydraulic oil circuit and exhaust the oil circuit. If the oil is polluted, clean the hydraulic components such as the valve body, drain and wash the oil circuit of the system, and replace the original hydraulic oil. If the viscosity of hydraulic oil is too high or too low, replace the hydraulic oil with the recommended viscosity.

The external leakage of the hydraulic system is mainly due to the damage of the sealing ring and the loss of sealing function; Hydraulic components are damaged, or air holes appear in the valve body. When dealing with the fault, disassemble and clean the hydraulic components, check whether the sealing ring meets the standard, and replace the damaged sealing ring and valve body.

2. Boom / bucket hydraulic system failure

(1) Fault phenomenon.

Common faults of boom / bucket hydraulic system include lifting hydraulic cylinder does not act, lifting hydraulic cylinder acts too slowly, lifting hydraulic cylinder produces fluctuation or impact, lifting boom cannot fall, bucket hydraulic cylinder does not act, bucket hydraulic cylinder acts too slowly, bucket hydraulic cylinder produces fluctuation or impact when acting, etc.

(2) Troubleshooting.

The main reasons for the failure of the lifting hydraulic cylinder are that the oil level of the oil tank is too low, the oil supply of the hydraulic pump is insufficient, the hydraulic pump does not work, the pressure oil cannot be output, the pressure of the system safety valve is improperly adjusted or has been damaged, so that the pressure of the lifting system cannot meet the requirements. The piston seal of the lifting hydraulic cylinder is damaged, resulting in great internal leakage of the hydraulic cylinder, damage of the external oil pipe, no or insufficient oil from the hydraulic cylinder, and the load in the bucket exceeds the lifting capacity of the hydraulic cylinder. When dealing with the fault, check the oil volume of the oil tank. If the oil level is too low, add the hydraulic oil to the specified oil level. The hydraulic pump is damaged and repaired. If it fails to meet the requirements after repair, it should be replaced. The pressure of the system safety valve is adjusted improperly. Readjust the safety valve to make the system pressure reach 21.0mpa. If the piston seal of the hydraulic cylinder is damaged, the pipeline is damaged and leaks oil, the seal and oil pipe should be replaced.

The main reason why the lifting hydraulic cylinder moves too slowly is that the oil supply of the hydraulic cylinder is insufficient and the seal of the hydraulic cylinder is damaged; Hydraulic oil leakage; The system oil circuit is blocked and the hydraulic oil flow is not smooth; The system safety valve or hydraulic cylinder overload safety valve is improperly adjusted, the boom components are deformed, there is no active clearance, there is a lack of lubrication, the boom hinge pin is damaged, and there is extrusion friction between moving parts. When dealing with the fault, check the oil level of the oil tank first. If the oil level is too low, add hydraulic oil. Repair and replace the damaged hydraulic pump. Clean the hydraulic oil circuit and oil tank, and replace the damaged seals. If the pressure of the system safety valve or the hydraulic cylinder overload safety valve does not meet the requirements, readjust the system safety valve to make the system pressure 21.0mpa and the hydraulic cylinder overload safety valve pressure 24.0mpa. If the hinge pin of the lifting arm is damaged, it should be replaced, and the place lacking lubrication should be filled with lubricating oil. If the boom member is deformed, it should be removed for correction.

The impact fluctuation of the lifting hydraulic cylinder is caused by the air entering the hydraulic system, the bending of the piston rod, the deformation of the cylinder barrel or the strain of the piston. Deal with this kind of fault, check the oil level of the oil tank, and fill it up if the oil quantity is insufficient. Inlet air at the joints, pipelines and hydraulic cylinder seals. Repair and replace the seals as needed. Repair the damaged hydraulic cylinder and piston rod.

The boom cannot fall when it is unloaded, mainly due to the failure of the hydraulic cylinder, the deformation of the boom components, no active clearance, lack of lubrication, and the damage of the boom hinge pin. When dealing with the fault, dismantle the deformed boom for correction, replace the damaged hinge pin, and fill the parts lacking lubrication with lubricating oil.

The fault causes and treatment measures of bucket hydraulic cylinder are similar to those of lifting hydraulic cylinder, and will not be repeated here.

3. Brake system failure

(1) Fault phenomenon.

Common faults of the braking system include braking failure, insufficient pressure of the braking system, failure of the accumulator and charging valve, etc.

(2) Troubleshooting.

Braking does not work because the oil level of the hydraulic oil tank is too low, and the hydraulic pump loses its function and cannot output sufficient pressure oil; The oil suction pipe, pressure oil pipe and pipe joint are damaged and leaking oil. When dealing with the fault, check the oil volume of the hydraulic oil tank. The oil volume is not enough to refuel. Repair the damaged hydraulic pump and replace the damaged seals and other components.

The insufficient pressure of the braking system is caused by the failure of the hydraulic pump, the improper adjustment of the opening pressure of the system safety valve, the leakage of the system oil pipe, etc. When dealing with the fault, check the damage of the hydraulic pump and repair the damaged parts. If there is no repair value, replace it with a new one. If the opening pressure of the system safety valve is too low, readjust the pressure setting value of the safety valve to 16.0mpa. If the oil pipe and joint are damaged and oil leaks, replace them with new ones.

Accumulator failure often occurs such phenomena as the accumulator cannot be charged with oil, the charging time is too long, the charging pressure is not high, and the charging is frequent. The main reasons are that the oil level in the oil tank is too low, the hydraulic pump fails, the inflation pressure of the accumulator airbag is improper, and the accumulator pipeline and joints are leaking oil or blocked. When dealing with the fault, check the oil level of the hydraulic oil tank. If the oil level is too low, add oil. If the pre charging pressure of the accumulator is too high or too low, adjust the pre charging pressure to 6.2mpa, repair the damaged hydraulic pump, and replace the damaged seals and oil pipes.

The failure of the charging valve is caused by wear or seizure of the valve core, aging and damage of the O-ring, fatigue and fracture of the charging valve spring, excessive impurities in the filter, blocking the oil circuit, etc. When dealing with the fault, check the wear condition of the valve core. If the wear of the valve core exceeds the limit, it should be replaced. If the dust of the filter is too much, clean the filter element, and check the spring force of the charging valve. If the spring force does not meet the standard, it should be replaced.

The main fault of the cable coiling hydraulic system is that the cable coiling does not work. The reason is that there is no oil in the hydraulic oil tank or the oil level is too low, the cable coiling hydraulic pump is damaged and cannot supply oil normally, and the cable coiling valve, oil pipe and connector are leaking or blocked.

The hydraulic cable winding motor fails, and the bearing of the hydraulic motor is seriously worn or damaged, so it cannot operate normally. When dealing with the fault, add oil according to the oil level of the oil tank, clean the filter element and oil circuit of the cable winding hydraulic system, and ensure the normal flow of oil. Check the system pressure. The pressure is 8.6mpa when winding the cable and 6.4Mpa when winding the cable. If the pressure does not meet the standard value, it should be adjusted in time. If the cable winding valve and hydraulic cable winding motor fail, repair them and replace them if they are seriously damaged.

4. Other troubleshooting

There are too many bubbles in the hydraulic oil. This is mainly due to the improper grade or viscosity of the oil, and a large amount of oil bypasses the overflow valve. When dealing with the fault, drain all the hydraulic oil and add appropriate hydraulic oil. If the pressure adjustment value of the overflow valve is too low, adjust the overflow valve as required, and replace it if it cannot be repaired.

The oil temperature of the hydraulic system is too high. This is mainly due to continuous maximum pressure operation, oil bypassing the overflow valve, incorrect oil grade or viscosity, and damage to the hydraulic pump. When dealing with the fault, drain all the oil in the hydraulic system, replace it with oil of appropriate viscosity, repair the damaged hydraulic pump, correct the operation method, and limit the long-term operation under the maximum pressure.

In short, the hydraulic system of tor0151e scraper must use the hydraulic oil recommended in the manual, and the viscosity of the oil should be appropriate when adding new oil. Adjust and replace the packing gland and sealing ring in time, and the oil pipe should be firmly installed to prevent air from entering the hydraulic system. Strengthen the maintenance of the hydraulic system to prevent the invasion of hydraulic oil pollutants. Keep the hydraulic system clean frequently and replace the hydraulic oil regularly, which can reduce the occurrence of hydraulic system faults.