How to deal with the slow action of concrete pump truck arm frame

Fault phenomenon: the concrete pump truck three arm movement is slow, with the increase of oil temperature, its speed is further reduced.

System analysis: concrete boom pump action is driven by hydraulic system, boom pump movement speed is determined by in and out boom cylinder flow. In a boom pump truck hydraulic system, due to the boom pump is quantitative pump, only the balance valve and boom multi-channel valve can change the boom cylinder flow.

Troubleshooting: when the arm frame moves slowly, the following steps can be checked:

1. Check whether the working pressure is normal, and if the working pressure is too high or the holding pressure is lower than the set value, the arm frame moves slowly;

2. If the working pressure is basically normal, try to increase the overflow valve pressure;

3. If there is no significant change in the phenomenon, remove the balance valve and check whether the balance valve is stuck.

4. As there is no sliding rod phenomenon when the arm frame works in various positions, internal leakage of oil cylinder is denied;

5. Considering the arm frame pump, since the working pressure is basically normal, the pump failure is not considered;

6. Check the multi-way valve and find that the three-arm disc has a high temperature. After cooling it with water, the phenomenon is significantly improved.