Due to various reasons such as worn parts and dirty transmission medium, the crawler hydraulic bulldozer will cause the bulldozer to turn hard, or even not to turn, or the cold car can turn and the hot car cannot turn (after the oil temperature of the transmission part rises to the working temperature) Failure phenomenon. After these failures occur, they must be classified and analyzed in combination with the use time of the bulldozer and the occurrence process of the failure, and the inspection should be carried out in a targeted manner to avoid unnecessary disassembly and reduce damage to the internal machinery.

　　The steering clutch used in general crawler bulldozers is a wet multi-plate constant engagement type. This steering clutch can transmit large torque and is suitable for working under harsh conditions. The engagement force of this steering clutch is provided by the elastic force of the spring deformation. The elastic force presses the friction plate and the tooth plate to ensure that there is enough friction between them to transmit torque to make the bulldozer work normally.

　　Push The turning process of the bulldozer is divided into two stages

　　The first stage: clutch disengagement gradually reduces the driving torque to zero

　　The second stage: the brake torque is provided by the brake to brake the car. These two stages are completed by hydraulic action. Because the bulldozer uses the hydraulic system to assist the operation, once the steering fails, the maintenance work becomes more complicated and difficult. The hydraulic crawler There are two cases of common steering failure of bulldozers

　　1: The bulldozer is always turning on one side, that is, as the saying goes, deviation (if both sides are turning, the symptom is weak work)

　　2: The bulldozer did not turn

　　One side does not turn or both sides do not turn. The reasons for these two situations are various. The failure of any part of the hydraulic system and the steering-related mechanical parts will cause the bulldozer steering to malfunction. The corresponding oil pressure should be carried out first. Measurement, that is, measuring the steering brake pressure of the bulldozer, comparing the measurement results with the standard values given in the bulldozer instruction manual, analyzing the steering brake hydraulic system to find out the factors that make the steering brake pressure abnormal, steering brake The hydraulic system mainly includes: hydraulic pump, pipeline, control valve, clutch, piston and brake booster. By analyzing the measured values, the fault location is determined.

　　Under normal circumstances: If the steering lever is not pulled, the measured pressure in front of the steering control valve is abnormal, usually due to damage to the safety valve. When this happens, first dismantle the safety valve and check whether the pressure regulating spring is broken or whether the pressure regulating piston is stuck. If there is no problem with the steering safety valve, check the pipeline before the valve and the hydraulic pump to ensure that the pipeline is unobstructed. If the pipeline is unobstructed, then check the performance of the hydraulic pump. If the pipeline or the hydraulic pump is faulty, it will cause insufficient oil supply. , The pressure required to disengage the steering clutch piston cannot be guaranteed.

　　The steering clutch is not thorough, causing steering failure.

　　Under normal circumstances, the pressure on the front of the valve is abnormal and the steering on both sides is malfunctioning. Find out the problem and repair it to solve the steering failure. If the pressure on the front of the valve is normal, you should consider other reasons, pull the steering lever, and measure the steering on the non-steering side. The output oil pressure of the valve, if the measured pressure is low (sometimes there is no pressure), it should be suspected that there is a leak on the measured side (inside of the steering clutch or connection disc), the steering clutch, the piston ring is damaged, the internal leakage of the clutch cannot be established When the normal pressure rises, the seal ring on the connecting disc is damaged or stuck in the groove of the seal ring, the steering control valve, the supply of oil leaks from here, the normal pressure supply cannot be established, and the hydraulic pressure of the steering clutch is insufficient. Failure to disengage the clutch or incomplete disengagement will cause steering failure. If the test results are all normal, then the bulldozer's steering failure, whether it is running or not, is only one possibility, that is, the steering clutch itself has a problem. Not turning because the piston is stuck in the working position. The normal oil pressure cannot separate it, resulting in steering failure, and the deviation is due to the clutch piston stuck in the disengaged position, which cannot always return to the normal transmission of torque. Sometimes the pressure spring of the steering clutch is broken or the pretension bolt is loose. The clutch engagement force is also enough to cause deviation. At this time, the steering clutch should be dismantled to eliminate the fault. In addition to the hydraulic system failure, the connecting rod adjustment bolts related to the steering brake, etc. If the size does not meet the requirements or improper adjustment, steering failure will also occur. After the bulldozer is used for a long period of time, each tie rod is often subjected to tension. The rods and rods may be elongated, and the connection between the rod and the rocker arm may also wear out due to long-term relative movement. These will cause abnormalities such as size. Among the two stages of bulldozer turning, the braking stage cannot be ignored. Improper braking will also result in steering failure, which should be considered in the inspection and analysis to eliminate the fault accurately.

　　The following problems should be paid attention to when adjusting the various connecting rods of Shantui bulldozers: The steering brake of the TY20 bulldozer is mechanically linked. When adjusting the steering brake link, the steering clearance should be left first to ensure that before the brakes take effect The steering clutch has been disengaged; the steering brake of the TY 160 and TY320B bulldozers is hydraulically linked. The linkage is completed on the hydraulic control valve. When adjusting the steering link, the specified clearance adjustment of the steering valve should be set aside, the brake link When you do not step on the brake pedal, you must ensure that the brake rocker arm is in a free state. If the connecting rod is improperly adjusted, it will fail. There are many reasons for the failure of the bulldozer steering, and the above are just common reasons.

　　Special circumstances such as: Pipe blockage: Steering valve rocker arm will fall off, etc., steering failure will occur, only a specific analysis based on the actual situation can completely solve the problem. Return the bulldozer to normal operation.