用途和適用范圍 Feature and application

自力式壓力調節閥（以下簡稱壓力閥）是一種無需外來能源而只依靠調介質自身的壓力變化進行自動調節壓力的節能型產品．具有測量、執行、控制的綜合功能。廣泛適用于石油、化工、冶金、輕工等工業部門及城市供熱、供噯系統。本產品可用于非腐蝕性（zui高溫度350℃）的液體、氣體和蒸汽等介質的壓力控制裝置。

Pressure self-regulating valve （herein after referred to as pressure valve）, a energy saving product, regulates pressure automatically without external energy supply. Pressure valve is used for pressure control device of non-corrosive liquid, gas and steam medium etc. that has integrated function of measure, performance and control. Pressure valve finds us in the field of petroleum, chemical industry, metallurgy and light industry and city heating system etc..

結構及工作原理 Structure and working principle

產品結構 Structure

本產品為直接作用型自力式壓力調節閥．由閥體、閥座、閥芯部件、閥蓋、頂盤、上、下膜蓋、膜片、彈簧、調節螺母等零部件所組成。

其具體結構參見圖la，圖lb、圖lc、圖ld所示：

Pressure valve is of direct action type, which is composed of body, seat, core parts, bonnet, highest quotation, diaphragm, spring, adjusting nut and upper and bottom diaphragm cover etc..

The specific structure sees chart 1a, 1b, 1c and 1d.

工作原理 Working principle

（I）作閥后壓力調節時的工作原理：（見圖la）

工藝介質的閥前壓力Pl經過閥芯、閥座的節流后，變為閥后壓力P2。P2經過控制管線輸入執行器的下膜室作用在頂盤上．產生的作用力與彈簧的反作用力相平衡．決定了閥芯、閥座的相對位置．控制閥后壓力。當閥后壓力P2增加時．P2作用在頂盤上的作用力也隨之增加。此時．頂盤的作用力大于彈簧的反作用力．使閥芯關向閥座的位置．直到頂盤的作用力與彈簧反作用力相平衡為止。這時．閥芯與閥座之間的流通面積減少．流阻變大．從而使P2降為設定值。同理，當閥后壓力P2降低時．作用方向與上述相反．這就是閥后壓力調節時的工作原理。當需要改變閥后壓力P2的設定值時．可調整調節螺母8。

（1）The working principle of regulating the back of valve’s pressure :（see chart 1a）

After being throttled by core and seat, P1 becomes P2.（P1 stands for the front of valve’s pressure and P2 stands for the back of valve’s pressure.）Getting through bottom diaphragm room, P2 acts on the highest quotation and creates acting force. The acting force keeps its balance with reacting force of spring, which decides the relative place of core and seat and controls the back of valve’s pressure. When P2 increases, the acting force is also increasing. Here, the acting force is bigger than the reacting force, which made the core close to the seat until balance. And the circulation area between core and seat decreases and flow resistance increases, thereby P2 fell to the setting value. Also, when P2 decreases, the acting force direction is contrary.

When P2 `s setting value needs to be changed, you can regulate the adjusting nut 8.