Multiport Selector Valve Load Direction Control and Selection

Multiport selector valve adopts a parallel oil circuit, designed with a pressure output port to connect with other hydraulic components to provide power source. After special design of the sealing method, the valve has excellent sealing performance. Multiport selector valves are widely used in hydraulic systems of forklifts, sanitation vehicles, small loaders and other construction machinery.

Ⅰ. Multiport Selector Valve Load Direction Control

Multiport reversing valve load direction changes in the course of work, in this case, take the "inlet side pressure control, outlet side flow control", in the hydraulic cylinder rod cavity side with pressure control, rodless cavity side with flow control. If the load direction remains unchanged, we can replace the two-way balancing valve with a liquid-controlled check valve to improve the stability of the system because the flow control is taken on the discharge side. The inlet side uses a pressure controller to maintain a low reference pressure to improve the system efficiency on one hand and keep the system from cavitation on the other.

Multiport selector valve in order to make the working mechanism of the load direction change can be well controlled, another PI controller will be applied to the pressure controller of the rod chamber, when the load direction change, the pressure of the rodless chamber will be reduced; if the rod chamber still maintain a very low pressure, when the load is large, the hydraulic cylinder will move in the opposite direction. When the PI controller detects that the rodless chamber pressure is lower than the set reference value, the multiport selector valve will increase the pressure set by the rodless chamber pressure controller to ensure the normal operation of the system.

Ⅱ. The Selection of Multiport Selector Valves to Consider What Issues?

Reversing valve is a type of multiposition valve, and its selection should be based on the action cycle and performance requirements of the system, combined with the specific characteristics of different components, and the applicable occasions.

1. According to the performance requirements of the system, select the neutral function and the number of bits and passes of the slide valve.

2. Consider the operation requirements of the multiport selector valve. For example, the manual manipulation with manual, pedal type; automatic manipulation with motorized, electric, hydraulic, electro-hydraulic type; long-distance manipulation with electric, electro-hydraulic type; requirements for smooth operation with motorized or main spool movement speed adjustable electro-hydraulic type; high reliability requirements with motorized.

3. We should make a choice according to the flow and working pressure of the multiport selector valve. Large working pressure and flow rate should generally be within the range of the selected valve and the highest flow rate should not exceed 120% of the rated flow rate of the selected valve, otherwise the pressure loss is too large, leading to heat and noise. If there is no suitable one, you can also use a higher pressure and flow rate of, but the economy is poor.

4. In addition, pay attention to the large working pressure, and also pay attention to the multiport reversing valve small control pressure to meet the requirements.

5. The choice of component connection - tube, plate and flange - should be determined according to the flow rate, pressure and the form of the component mounting mechanism.

6. If the flow rate is more than 63L / min, we can not choose a solenoid valve, otherwise the electromagnetic force is too small to push the valve spool. At this time, you can use other forms of control reversing valve, such as hydraulic and electro-hydraulic reversing valve.