Working Principle
When water is supplied to the pipeline from the inlet end of the valve, since the needle valve 14, ball valve 8, and float valve 5 are normally open, water passes through the micro filter 13 and needle valve 14 into the valve cover control chamber, then flows into the water tank via the ball valve 8 and float valve 5. No pressure builds up in the control chamber, so the inlet pressure below the main valve disc lifts the main valve disc, allowing a large volume of water to flow into the tank.
As the water level in the pool or water tower rises gradually, the float rises and closes the float valve 5. This causes water in the valve cover control chamber to gradually build up pressure until the main valve disc is closed, thereby achieving automatic remote control. When the water level drops to a certain point, the float descends with the water surface, opening the float valve. Water in the control chamber drains, pressure decreases, and the main valve disc is lifted to promptly replenish water in the pool or water tower.
(This is the working principle of the diaphragm type, and the piston type operates similarly.)

Piston Structure Type
This valve consists of a main valve, needle valve, ball valve, float valve, micro-filter, etc., as shown in the figure.Its structure is a hydraulically controlled shut-off type. According to different calibers, it adopts rubber diaphragm type and piston type to connect the valve disc for opening and closing.
Main Components and Materials
| 编号Number | 零件名称Part Name | 材 质Material |
| 1 | 阀 体Valve Body | 铸铁、不锈钢Cast Iron.Stainless Steel |
| 2 | 阀 座Valve Seat | 铜、不锈钢Copper.Stainless Steel |
| 3 | 密封垫Gasket | 强化橡胶Reinforced Rubber |
| 4 | 密封垫压板Gasket Pressure Plate | 铜、不锈钢Copper.Stainless Steel |
| 5 | 浮球阀Float Valve | 青 铜Bronze |
| 6 | 阀 盘Valve Disc | 铜、不锈钢Copper.Stainless Steel |
| 7 | 膜 片Diaphragm | 强化橡胶Reinforced Rubber |
| 8 | 球 阀Ball Valve | 铜Copper |
| 9 | 膜片压板Diaphragm Pressure Plate | 铜、不锈钢Copper.Stainless Steel |
| 10 | 弹 簧Spring | 不锈钢Stainless Steel |
| 11 | 阀 杆Valve Stem | 不锈钢Stainless Steel |
| 12 | 阀 盖Valve Cover | 铸铁、不锈钢Cast Iron.Stainless Steel |
| 13 | 微型过滤器Micro Filter | 不锈钢Stainless Steel |
| 14 | 针阀Needle Valve | 铜Copper |