The slewing motor is the core component of the slewing organization of the excavator. The pros and cons of its working characteristics will immediately harm the slewing rate of the entire equipment. The drive torque, slewing parking and parking brake are important for determining the output rate of the entire equipment. . But it is also a pity. Swing motors are components that are prone to abnormalities in excavators, and they are complicated and expensive to repair, and spare parts are also expensive.
Common fault conditions and root causes:
When the excavator is working in a relatively low temperature condition, the driving force and the rotation rate are not significantly reduced.When the oil temperature rises to about 60CC, the rotation is weak, the rotation speed ratio is unstable, and the speed ratio is higher and sometimes lower.
The common faults mentioned above, in addition to the pumps, valves and other components in the rotary system software, the key is that the internal fitness exercises of the rotary motor cooperate with each other to cause damage, increase the gap, increase the leakage, and the pump oil cannot be discharged immediately. In addition, there is a lot of leakage of high-pressure hydraulic oil, which causes the working pressure in the casing to increase, the temperature of the hydraulic oil rises, and the viscosity decreases.
inspection method:
1. Stability test
Use a blind plate to protect the fuel pipe of the slewing motor from the main fuel pipe, and use an oil pressure gauge to detect the vapor pressure of the slewing motor's forward rotation and turning over the oil inlet and outlet, and then obtain the working pressure value of the slewing motor. Then connect the fuel pipe to make It is in all normal working attitudes, the excavator bucket is dropped and inserted on the road, the load of the rotary service platform increases, and then the working pressure of the speed control valve when the motor driver is detected, and the two data tests are carried out to compare, it can be judged Common fault conditions.
2. Total flow detection
Connect the PFM-6 steam flow meter in series to the oil passage, detect the total flow rate and working pressure of the rotary motor inlet and outlet, determine whether the rotary motor output torque and speed ratio exceed its technical performance parameters, and can distinguish the abnormality of the rotary motor position.
Common troubleshooting methods:
1) The damage to the gap between the plunger and the plunger hole of the engine block increases, causing a relatively serious gap leakage, and the plunger needs to be replaced.
2) The return spring is tired and its elasticity is reduced, causing collusion of the high-pressure and low-pressure fuel pipes of the engine block, and the spring yellow needs to be replaced.
3) The sliding shoe and the plunger ball are damaged, which speeds up the dry friction between the sliding shoe and the pressure plate, which causes the rotation friction resistance to increase, and needs to be repaired or replaced.
4) The rolling bearing of the slewing motor is damaged, and the accurate positioning of the rolling bearing is invalid. The rolling bearing of the required model and specification needs to be replaced.
5) Valve EX200-1 needs to be repaired or replaced.
6) The hydraulic cylinder seals of the parking brake system are embrittled, ineffective, and oil seepage, causing the brake system to not be completely eliminated, and the rotational friction resistance increases, and the sealing components need to be replaced.
7) The valve plate and the oil level of the engine cylinder are damaged, causing internal leakage and weak rotation, which needs to be repaired or replaced.
8) Sealing components are gnawed, embrittled, and invalid, and should be replaced.
According to the detailed introduction in the article, many machine friends can figure out that this common fault can actually be avoided. If the customer can pay enough attention to maintenance when using the excavator, it will not cause such a big problem in the middle and late stages. damage. Therefore, the excavator maintenance and operation specialist once again reminded everyone that excavators are not invincible, so you must be careful and careful in daily maintenance, and you can't ignore every key point!
