TESCOM减压阀44系列工作原理

TESCOM减压阀44系列工作原理

当减压阀的输出压力较高或通径较大时，用调压弹簧直接调压，则弹簧刚度必然过大，流量变化时，输出压力波动较大，阀的结构尺寸也将增大。为了克服这些缺点，可采用先导式减压阀。先导式减压阀的工作原理与直动式的基本相同。先导式减压阀所用的调压气体，是由小型的直动式减压阀供给的。若把小型直动式减压阀装在阀体内部，则称为内部先导式减压阀；若将小型直动式减压阀装在主阀体外部，则称为外部先导式减压阀。 内部先导式减压阀与直动式减压阀相比，该阀增加了由喷嘴4、挡板3、固定节流孔9及气室B所组成的喷嘴挡板放大环节。当喷嘴与挡板之间的距离发生微小变化时，就会使B室中的压力发生很明显的变化，从而引起膜片10有较大的位移，去控制阀芯6的上下移动，使进气阀口8开大或关小、提高了对阀芯控制的灵敏度，即提高了稳压精度。

外部先导式减压阀的工作原理与直动式相同。在主阀体外部还有一个小型直动式减压阀，由它来控制主阀。此类阀适于通径在20mm以上，远距离(30m以内)、高处、危险处、调压困难的场合。

Working principle of TESCOM pressure reducing valve 44 series

When the output pressure of the pressure reducing valve is high or the diameter

is large, directly adjusting the pressure with a pressure regulating spring will

inevitably result in excessive spring stiffness. When the flow rate changes, the

output pressure fluctuates greatly, and the structural size of the valve will also

increase. To overcome these shortcomings, pilot operated pressure reducing

valves can be used. The working principle of a pilot operated pressure reducing

valve is basically the same as that of a direct acting valve. The pressure

regulating gas used in the pilot operated pressure reducing valve is supplied by a

small direct acting pressure reducing valve. If a small direct acting pressure

reducing valve is installed inside the valve body, it is called an internal pilot

pressure reducing valve; If a small direct acting pressure reducing valve is

installed outside the main valve body, it is called an external pilot operated

pressure reducing valve. Compared with the direct acting pressure reducing

valve, the internal pilot type pressure reducing valve adds a nozzle baffle

amplification link composed of nozzle 4, baffle 3, fixed orifice 9, and air chamber

B. When there is a slight change in the distance between the nozzle and the

baffle, it will cause a significant change in the pressure in chamber B, causing a

significant displacement of diaphragm 10 to control the up and down movement of

valve core 6, causing inlet valve port 8 to open or close larger, improving the

sensitivity of valve core control, and thus improving the stability accuracy.

The working principle of the externally piloted pressure reducing valve is the same

S that of the direct acting type. There is also a small direct acting pressure

reducing valve outside the main valve body, which controls the main valve. This

type of valve is suitable for situations with a diameter of over 20mm, long-distance