Common faults and maintenance of automobile electric butterfly valve
The electric butterfly valve is a vulnerable part in the process of vehicle operation. The operation of the electric butterfly valve will directly affect the stability of the vehicle and the life of other parts. Therefore, we should keep the electric butterfly valve in good working condition. The following methods can be used to check whether the electric butterfly valve works well.
1. Stop the car after driving 10km on the road with poor road conditions, touch the shell of the electric butterfly valve with your hand. If it is not hot enough, explain that there is no resistance inside the electric butterfly valve, and the electric butterfly valve does not work. At this time, take part in the appropriate lubricating oil, and then stop the test. If the shell is hot, the electric butterfly valve is short of oil, and it should be filled with enough oil; Otherwise, the electric butterfly valve is invalid.
2. Press the bumper firmly, and then release it. If the car jumps 2-3 times, it indicates that the electric butterfly valve works well.
3. If the vehicle vibrates violently in case of slow driving and emergency braking, it indicates that the electric butterfly valve is faulty.
4. Dismantle the electric butterfly valve to make it upright, clamp the lower connecting ring on the bench clamp, and pull and press the shock absorber rod several times with force. At this time, there should be stable resistance. The resistance of pulling upward should be greater than the resistance of pressing downward. If the resistance is unstable or no resistance, it may be the lack of oil inside the electric butterfly valve or the damage of valve parts, and the repair or replacement of parts should be stopped.
After confirming that the electric butterfly valve has a problem or failure, check whether the electric butterfly valve can leak oil or has traces of obsolete oil leakage. The oil seal washer and seal washer are cracked and damaged, and the nuts of the oil storage cylinder cover are loose. The oil seal and sealing washer may be damaged and invalid, so the seal shall be replaced with a new one. If the oil leakage still cannot be eliminated, the electric butterfly valve should be pulled out. If it feels stuck or different, further check whether the clearance between the piston and the cylinder barrel is too large, whether the piston connecting rod of the electric butterfly valve is bent, and whether the piston connecting rod surface and cylinder barrel are scratched or pulled.
If there is no oil leakage from the electric butterfly valve, check whether the electric butterfly valve connecting pin, connecting rod, connecting hole, bushing, etc. are damaged, desoldered, cracked or scattered. If the above inspection is normal, the electric butterfly valve shall be further synthesized to check whether the fit clearance between the piston and the cylinder barrel is too large, whether the cylinder barrel is strained, whether the valve seal is good, whether the valve clack fits tightly with the valve seat, and whether the stretch butterfly valve of the electric butterfly valve is too soft or broken. According to the condition, the method of grinding or replacing parts shall be adopted for repair.
In addition, the electric butterfly valve will make a noise in practical application, which is mainly caused by the collision between the electric butterfly valve and the steel plate butterfly valve, the frame or the shaft, the damaged or scattered rubber gasket, the deformation of the electric butterfly valve dust cylinder, the lack of oil and other reasons. The reason should be found out and repaired.
After the inspection and repair of the electric butterfly valve is stopped, the working performance test shall be stopped on the special test bench. When the resistance frequency is 100 ± 1mm, the resistance of its stretching stroke and tightening stroke shall conform to the rules. For example, the maximum resistance of Jiefang CAl091 stretching stroke is 2156~2646N, and the maximum resistance of tightening stroke is 392~588N; The maximum resistance of Dongfeng truck in stretching travel is 2450~3038N, and that in tightening travel is 490~686N. If there is no experimental condition, we can also adopt an empirical approach, that is, use an iron bar to penetrate into the lower lifting ring of the electric butterfly valve, step on its two ends with both feet, hold the upper lifting ring with both hands and pull it back and forth for 2 to 4 times. When it is pulled upward, the resistance is great, and when it is pressed downward, it does not feel laborious, and the resistance of stretching is recovered compared with that before repair, there is no sense of emptiness, It indicates that the electric butterfly valve is basically normal.