The pressure tank is used in the closed water circulation system to balance the water volume and pressure, avoid frequent opening of the safety valve and frequent water supply of the automatic replenishment valve. The expansion tank plays the role of accommodating the expansion water, and also functions as a replenishing tank. The expansion tank is filled with nitrogen gas, and a large volume can be obtained to accommodate the amount of expansion water. The high and low pressure expansion tanks can use their own pressure and are connected to the regulating system. Make up water. All the control points of the device are interlocking reactions, automatic operation, small pressure fluctuation range, safety, reliability, energy saving, and good economic effect.
The pressure tank uses the compressibility of the air in the tank to regulate and store the water volume and maintain the required pressure. Therefore, it is also called a pressure water supply equipment, and its function is equivalent to a water tower and a high water tank. Since its water supply pressure is maintained by the compressed air in the tank, the installation height of the tank body can be unlimited. In addition, such equipment has less investment, rapid construction, easy demolition, high flexibility and high degree of automation, and is suitable for water supply in small and medium-sized villages with adequate water supply and normal power supply. However, it has a small amount of regulating water, rapid pressure decay, frequent pump start-up, high operating costs, and is not suitable for users with large water consumption and requiring stable pressure.
Pressure tanks are generally installed between the pump and the pipe network. After the pump is started, it will supply water to the pipe network. The excess water will be stored in the tank and the water level in the tank will rise. The air in the tank will be compressed and the pressure will increase. When the pressure in the tank reaches the specified upper pressure limit, the indicator of the electrical contact pressure gauge connected to the top of the tank connects to the upper limit contact, signals, cuts off the power, and stops the pump. The user continues to use water, and the compressed air in the tank presses the water in the tank into the pipe network, the water level drops, and the air pressure in the tank also drops. When falling to the required lower limit pressure value, the indicator of the electrical contact pressure gauge is connected to the lower limit contact, the relay operates, the motor and the power supply are connected, and the water pump restarts. Under normal circumstances, the pump can work under uncontrolled conditions, and can adjust the number of open and stop times of the pump and the working time according to the change of water consumption to ensure continuous water supply to the pipe network.