In practice, hydraulic lock will also appear some problems, for everyone to understand, we will use a case to explain. First, we chose a typical hydraulic lock loop of a double hydraulic check valve. When the reversing valve is in the middle position, the two hydraulic check valves will close immediately and the piston will return to the static state.

In this case, the piston can be locked in the stop position for a long time due to the good sealing effect of the hydraulic check valve. However, in practical application, the circuit is not suitable for applications with strong vibration load. Because if the load strongly vibrates, then it will cause the piston rod to drive the piston to swing from side to side, in this way, it will cause the hydraulic cylinder with and without the rod cavity to alternately form the negative pressure chamber and the compression chamber.

Since the two Chambers and the back pressure of the hydraulic cylinder are in a connected state, usually the past pressure range is 0.2-0. 5MPa. in this state, it is able to open the one-way valve of the hydraulic lock and enter the negative pressure area of the cylinder. At the same time, due to the influence of the hydraulic lock, the oil in the pressure chamber cannot be discharged, and is squeezed into high pressure. With the continuous vibration operation, the pressure of the two Chambers of the cylinder will always rise.

For example, when we measure the system pressure of 6MPa, we will find that the actual pressure of its hydraulic cylinder has reached 15MPa. In this case, if unloading occurs, it will lead to serious accidents. Because in practical applications, it is usually required to ensure the piston chamber pressure.

In order to solve this problem, we can take such measures to deal with: for example, the loop of the double hydraulic control one-way valve to the single side of the hydraulic control one-way valve, in this way, not only can play the role of locking chamber pressure, but also can effectively prevent the hydraulic cylinder piston rod chamber from establishing pressure.