水力控制阀简述

　　Brief introduction of waterpower control valve

　　1.结构特点

　　水力控制阀一般分为隔膜型和活塞型两大类，两者工作原理相同，它由一个主阀（如图1 .2）及其外装的针阀、导阀、导管和压力表等组合而成。并配合使用目的、功能及场所的不同而演变成遥控浮球阀、减压阀、缓闭止回阀、流量控制阀、泄压/持压阀、水力电动控制阀、定水位阀、水泵控制阀、紧急关闭阀等。

　　Structure characteristics

　　The control valve for waterpower can be classified into the dissepiment type and the plunger type, which are of the same working principle. It is made up of a master valve（figurel、2） and a outside needle valve,  pilot valve, pipe and pressure gauge etc. It also can be categorized into float valve for  remote control, reducing valve, slow close check valve, flow control valve,  releasing pressure/keeping pressure valve, electric control valve for waterpower, water level valve, water pump control valve, emergency shutoff valve according to the using purposes and functions as well as the places in service.

　　2.动作原理

　　水力控制阀以上下游压力差△P为动力，实行自动调节，从而使主阀阀盘完全开启或同时关闭，或处于调节状态。

　　Working principles

　　Control valve for waterpower can be adjusted automatically depending on the different pressure between upriver and downsteam making the disc of the master valve open completely or close fully at the same time, or valve in adjusting condition.

　　全闭状态：当主阀进口端水压分别进入阀体及控制室，且主阀外部之球阀同时关闭，此时主阀处于全闭状态，

　　Full cut-off condition: when inlet pressure enters body and control room, meanwhile the exterior ball valve of the master valve closes so the master valve sha日be in condition of f}川cut-off:

　　全开状态：当主阀外部球阀全开后，此时控制室内水压全部被排到大气或下游低压区时，主阀呈全开状态，

　　Full opening condition: After the exterior ball valve of master valve opens completely, the control room pressure is let out to the air or the downsteam lower pressure area to make the master valve be in condition of full opening.

　　浮动状态：调节主阀外部之球阀开度，使水流经过针阀与球阀之间水流达到平衡，此时主阀处于浮动状态。

　　Floating condition:the open-close degree of adjust the exterior ball valve of the master valve，make the flow through  needle valve and ball valve balance, at this time the master valve shall be in floating condition.