Dalan Hydraulic Analysis Common Faults of Hydraulic Directional Valves

The difference between the hydraulic directional Control Valve and the electromagnetic directional control valve is that the force that pushes the spool is different.
The difference between the hydraulic directional control valve and the electromagnetic directional control valve is that the force that pushes the spool is different.

The former is the hydraulic pressure of the pressure oil, the latter is the suction of the electromagnet, and the failure analysis and elimination method of the specific hydraulic directional control valve tells you that there are the following points.

Fault 1: no commutation or poor commutation

the reason:

1. The pressure of the control pressure oil that pushes the spool to move is insufficient;

2. Although the control of oil pressure is sufficient, but the other end of the valve core controls the oil return of the oil chamber is not smooth, the cause of the poor may be the blockage of dirt, or the amount of opening is not large enough, or the back pressure of the oil back is large.

All of the above situations cause the spool of the hydraulic directional control valve to be unable to move or move inflexibly, so that it cannot be reversed or poorly commutated.

Solution:

1. Appropriately increase the pressure of the control oil. The control oil pressure range of the hydraulic directional valve of the 6.3mpa series is 0.3-6.3mpa, and the valve control pressure oil pressure range of the 32mpa series is 1-32mpa, which is lower than the lowest value. The valve cannot be reversed.

2. For the hydraulic reversing valve such as m, h, k type with the intermediate position in the unloading state, if the control oil is taken from the system, a back valve must be installed on the returning oil line, and the back adjustment value must be Large enough to have enough pressure to control the oil to move the spool.

3. If the return spring is not broken, the return spring must be replaced.

4. When the bonnet direction is wrongly installed during the disassembly, the control oil will not enter the oil or the oil will not pass, resulting in no reversing. At this time, the bonnet assembly direction should be corrected. The control port on the bonnet should face the control port on the end face of the valve body: for the control oil to be introduced from the top cover, also pay attention to the direction of the cover plate.

Fault 2: The commutation vibration is large and there is a commutation shock

Cause: The commutation shock occurs when the port pressure changes drastically during commutation. At this time, the spool reversing speed is generally too fast.

Solution:

1. In order to make the pressure change slow, it is necessary to try to make the spool reversing speed slower, and a small adjustable one-way throttle valve can be connected in series on the control oil line at both ends of the valve;

Taking the design of the reversing valve core shoulder or processing into a conical surface or opening a triangular throttle groove, most of the impact problems can be solved.








----- Editor-in-Chief: Dalan Oil Pump Motor 02-Procurement Consultant

Copyright http: / (Dalan Motor) Reprint, please indicate the source
Http://news.chinawj.com.cn Editor: (Hardware Business Network Information Center) http://news.chinawj.com.cn