Our plastic (ABS) two-position three-way valve is lighter and rustless than those made of iron. It's added anti-aging to prevent aging after sunlight. And every valve have been pressure tested before shipment (15kg).

1.Schematic Diagram of Filtration and Back-purge of Internal Source Back-purge Equipment:

    Water to be treated will flow into two-position three-way valve from inlet pipe. The stream controlled by valve will flow into each filtering unit to filter. The filtered water will flow into outlet from the channel of filtering inner unit. The impurity absorbed by filter will increase while the filtration is carried out. When the difference of pressure reaches to the set value or the set time, the system will carry out the mode of back-purge. First the controller will send the signal to three-way valve related to the first filtering unit. This valve will change the direction of stream and close water-in and turn on sewage draining exit. Under the reaction of pressure the back-purge water will pass through outlet pipe and rush into the filter to carry out wash and the sewage will be discharged by sewage draining exit. After the wash is finished, the unit will recover into the filtering mode and this system will carry out back-purge to next unit till all unit is washed fully and the system recovers to its filtering mode. According to the condition of pressure at outlet pipe, under the condition of pressure that is not enough to support back-purge, install solenoid valve at outlet pipe to control water flow in order to meet the requirement of washing. (As figure 1, figure 2)

Figure 1

Figure 2

    Water to be treated will flow into two-position three-way valve from inlet pipe. The stream controlled by valve will flow into each filtering unit to filter. The filtered water will flow into outlet valve from the channel of filtering inner unit and is controlled by valve and then flow into outlet pipe. When the difference of pressure reaches to the set time, the system will carry out the mode of back-purge. First the controller will send the signal to three-way valve related to the first filtering unit. This valve will change the direction of stream and flow into three-way valve and close water-in three-way valve and turn on sewage draining exit. Close water-out three-way valve and turn on water-out outer washing inlet. The back-purge water adjusted by water-out three-way valve will flow into the filter to carry out washing. The sewage will be discharged by sewage draining exit. After the wash is finished, the unit will recover into the filtering mode and this system will carry out back-purge to next unit till all unit is washed fully and the system recovers to its filtering mode. (As figure 3, figure 4)

Figure 3

Figure 4