TESCOM減壓閥44系列工作原理

當(dāng)減壓閥的輸出壓力較高或通徑較大時，用調(diào)壓彈簧直接調(diào)壓，則彈簧剛度必然過大，流量變化時，輸出壓力波動較大，閥的結(jié)構(gòu)尺寸也將增大。為了克服這些缺點，可采用先導(dǎo)式減壓閥。先導(dǎo)式減壓閥的工作原理與直動式的基本相同。先導(dǎo)式減壓閥所用的調(diào)壓氣體，是由小型的直動式減壓閥供給的。若把小型直動式減壓閥裝在閥體內(nèi)部，則稱為內(nèi)部先導(dǎo)式減壓閥；若將小型直動式減壓閥裝在主閥體外部，則稱為外部先導(dǎo)式減壓閥。 內(nèi)部先導(dǎo)式減壓閥與直動式減壓閥相比，該閥增加了由噴嘴4、擋板3、固定節(jié)流孔9及氣室B所組成的噴嘴擋板放大環(huán)節(jié)。當(dāng)噴嘴與擋板之間的距離發(fā)生微小變化時，就會使B室中的壓力發(fā)生很明顯的變化，從而引起膜片10有較大的位移，去控制閥芯6的上下移動，使進氣閥口8開大或關(guān)小、提高了對閥芯控制的靈敏度，即提高了穩(wěn)壓精度。

外部先導(dǎo)式減壓閥的工作原理與直動式相同。在主閥體外部還有一個小型直動式減壓閥，由它來控制主閥。此類閥適于通徑在20mm以上，遠距離(30m以內(nèi))、高處、危險處、調(diào)壓困難的場合。

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