Ductile Iron Diaphragm-Type Remote Control Float Valve F745X-16Q

Product Description

The F745X multifunctional remote control float valve is a hydraulically operated valve that combines multiple functions. It is primarily installed at the inlet of a reservoir or elevated water tower. When the water level reaches a preset height, the main valve is controlled by a float pilot valve to close the inlet and stop water supply; when the water level drops, the main valve is controlled by the float pilot valve to open the inlet and fill the reservoir, thereby achieving automatic water replenishment. It provides accurate level control that is unaffected by water pressure; the remote control float valve can be installed in any position depending on the height of the reservoir and available space. It is easy to maintain, commission, and inspect, offers reliable sealing, and has a long service life.

Product Features

1. Tight and reliable sealing: Featuring a robust O-ring seal and utilizing the principle of pressure control, the closing force of the sliding disc is directly proportional to the inlet water pressure, ensuring a highly reliable seal.
2. High flow capacity: The valve features a full-bore, streamlined design that minimizes fluid resistance and maximizes flow capacity.
3. Operational safety: Using hydraulic operation, the liquid level in water towers or reservoirs can be automatically controlled with a high degree of accuracy.
4. Easy to use and maintain: The main valve is installed outside the tank, making it easy to commission and inspect, and simple to repair.

How It Works

The F745X diaphragm-type remote control float valve is primarily installed at the inlet of a reservoir or elevated water tower. When the water level falls below the user-set level, the float valve in the reservoir opens, allowing pressurized water from the main valve's control chamber to flow into the reservoir through a conduit. The pressure in the main valve's control chamber gradually decreases and approaches zero. Pressurized water at the main valve inlet acts on the valve stem. When the resulting force overcomes the combined force of the spring-loaded spring in the main valve control chamber and the weight of the valve stem, the valve stem rises, the main valve opens, and the piping system begins supplying water to the reservoir. Once the valve stem opens, the pressure in the main valve control chamber equals the pressure at the main valve inlet. When the water level reaches the user-set activation level, the float of the float valve in the reservoir rises due to the buoyancy of the water and closes. The pressure in the main valve control chamber then equals the pressure at the main valve inlet. Since the area of the diaphragm is larger than that of the valve stem, even though the pressures in the main valve control chamber and at the main valve inlet are equal, the forces exerted by the pressurized water on the diaphragm and the valve stem differ. The force on the diaphragm is greater, causing the valve stem to tend to move downward and close the main valve. Consequently, the valve stem automatically closes under the combined action of the force exerted by the backflow medium at a certain pressure, the spring-loaded force, and the weight of the valve stem itself.

Structural Features

Multifunctional pump control valves are generally classified into two main types: diaphragm-type and piston-type, both of which operate on the same principle. The valve drive mechanism employs a dual-chamber control structure, in which a separate control chamber is isolated downstream of the lower chamber containing the diaphragm (or piston). Valves in this series are configured by connecting the dual chambers within the main valve to externally mounted pilot valves, tubing, regulating valves, and pressure gauges to form valve assemblies tailored to different applications, purposes, and functions.

How the Main Valve Works

The multifunctional pump control valve uses a dual-chamber control chamber to apply hydraulic principles to slowly open the main valve plate into a regulated state. Piston-type valves can also be equipped with an adjustment screw mechanism on the valve cover, allowing control of the valve's maximum opening and flow rate, as well as manual closure when necessary.

Fully Open State

When the pump starts, the pressure at the valve inlet rises. The pressurized water pushes the main valve plate open while also flowing through the piping system into the lower chamber of the diaphragm (piston). Meanwhile, the water in the upper chamber of the diaphragm (piston) is drained through the piping system into the valve outlet, where the pressure is lower, causing the valve to open slowly under the combined action of these two forces.

Fully Closed State

When the pump stops, the flow velocity of the water in the valve decreases; as it approaches zero, the main valve disc closes rapidly under the combined action of spring force and its own weight, while the pressurized water downstream of the valve returns through the piping system to the upper chamber of the diaphragm (piston), pushing the small valve disc on the fixed valve stem to close slowly.

Product Specifications

Product Size Guide