Flow regulating valve

Principle of piston type flow and pressure regulating valve

The piston type flow and pressure regulating valve is mainly composed of a valve body, a water outlet valve body, a valve seat, a piston, a squirrel cage (fan blade ring), a valve stem, a crank, a connecting rod, a shaft sleeve, a guide rail, a piston frame, a sealing ring, a main valve, an electric drive device, a PLC control system, and a pressure sensor (flow meter).

The adjustment of piston type flow and pressure regulating valves is mainly achieved by changing the medium flow area between the closing element (piston) and the sealing surface of the valve seat, in order to regulate the flow rate (or pressure). The valve body is designed with an inner and outer cylindrical structure, making the structure of the valve more in line with water flow control technology. The adjusting mechanism is a crank slider mechanism, and the closing slider is a cylindrical piston that can move axially along the center of the pipeline guided by a guide rail in the wide body cylinder, thus changing the flow area to achieve control and adjustment functions. The inner cavity of the valve body is a streamlined center axis symmetrical flow channel, which guides the fluid well inside the valve body, reduces water resistance, and minimizes head loss. The cross-section of water flow at any position inside the valve chamber is circular. The annular throttling surface of the piston at any position ensures the linear operating characteristics of the valve. The crank slider mechanism operates stably and reliably, with a constant output torque. It closes quickly and then slowly, thus not generating any water hammer.

Structure of piston type flow and pressure regulating valve

The design of piston type flow and pressure regulating valves is generally determined by the selection of their structure and size based on the system pressure conditions and the conditions of high and low flow rates. There are significant differences in the requirements and technical conditions of various working conditions. The precise control of output is extremely difficult for traditional regulating valves in flow regulation and pressure control, which is determined by the inherent structure and operation execution mode of the regulating components of traditional regulating valves. The piston type flow and pressure regulating valve can adapt to different working conditions and has excellent performance and good adaptability. The valve body is designed as an integrated and segmented type; The closing adjustment part is designed as a combination piston and multifunctional valve seat structure. When there are different requirements for the system, designing different pistons and multifunctional valve seats for closing adjustment or small adjustments can meet the requirements. By analyzing the operating characteristics of the regulating valve, the piston type flow and pressure regulating valve is designed in two standard types: squirrel cage and fan blade. The squirrel cage structure is divided into porous piston cylinder LH type, double-layer porous piston cylinder LL type, multi slot piston cylinder SZ type, and special type piston cylinder XT type; The fan blade structure is divided into an E-type multifunctional valve seat for venting and releasing, and an S-type multifunctional valve seat for fan blade rings. When there are special requirements in the system, slight modifications to the design can meet their personalized needs. At the same time, it also solves various technical problems in certain high demand working conditions, especially in high-precision, large pressure difference, and large flow rate tuning.

Main connection dimensions