Working Principle
When the water pump starts operating, the water flow at the inlet end of the valve passes through the micro filter, needle valve 14, pressure control chamber, electromagnetic pilot valve 8, ball valve 6 in sequence, and is discharged to the outlet. At this time, the electromagnetic pilot valve is energized (the solenoid valve works synchronously with the water pump motor) and remains in a normally open state. Due to the small opening of needle valve 14 and the smaller diameter of the inlet pipe compared to the outlet pipe, the discharge speed in the control chamber is greater than the water replenishment speed. As a result, the pressure in the control chamber decreases, and the inlet pressure acting under the main valve disc lifts the main valve disc, thereby opening the main valve to supply water downstream.
When water supply needs to be stopped, the water pump motor shuts down, and the electromagnetic pilot valve 14 closes due to power failure (normally closed state). Since the downstream water starts to flow back and the self-weight of the valve disc causes the throttle port to close quickly by 90%, the remaining 10% uses the pipe to transmit the pressure behind the valve to the upper water chamber. Due to the action of the electromagnetic pilot valve, the pressure in the upper water chamber gradually increases, eventually causing the main valve disc to close tightly. This prevents downstream water from flowing back, protects the water pump motor, and also plays a role in slow closing and noise elimination. (This is the working principle of the diaphragm type, and the piston type works similarly.)

Structural diagram of 600X piston type hydraulic electric control valve
This valve consists of a main valve, a needle valve, a ball valve, an electromagnetic pilot valve, etc. According to the requirements of different pipe positions, it can be divided into two types: rubber diaphragm type and piston type.
Main Components and Materials
| Serial Number | Part Name | Material | | Serial Number | Part Name | Material |
| 1 | 阀 体Valve Body | 铸铁、不锈钢Cast Iron, Stainless Steel | 8 | 电磁向导阀Electromagnetic Pilot Valve | 不锈钢Stainless Steel |
| 2 | 阀 座Valve Seat | 铜、不锈钢Copper, Stainless Steel | 9 | 膜片压板Diaphragm Pressure Plate | 铜、不锈钢Copper, Stainless Steel |
| 3 | 密封垫Gasket | 强化橡胶Reinforced Rubber | 10 | 阀 盖Valve Cover | 铸铁、不锈钢Cast Iron, Stainless Steel |
| 4 | 密封垫压板Gasket Pressure Plate | 铜、不锈钢Copper, Stainless Steel | 11 | 压缩弹簧Compression Spring | 不锈钢Stainless Steel |
| 5 | 阀 盘Valve Disc | 铜、不锈钢Copper, Stainless Steel | 12 | 阀杆Valve Stem | 不锈钢Stainless Steel |
| 6 | 球 阀Ball Valve | 铜Copper | 13 | 微型过滤器Micro Filter | 不锈钢Stainless Steel |
| 7 | 膜 片Diaphragm | 强化橡胶Reinforced Rubber | 14 | 针 阀Needle Valve | 铜Copper |