原文：
　锻钢闸阀用于截断或接通管路中的介质，选用不同的材质，可分别适用于水、蒸汽、油品、硝酸、醋酸、氧化性介质、尿素等多种介质。它有三种体盖连接设计形式，如下 {dy}种：体盖焊接连接锻钢闸阀，按这种连接形式设计的阀门，其阀体与阀盖全焊密封，优点是无外泄漏 第二种：体盖螺栓连接锻钢闸阀，按这种连接形式设计的阀门，其阀体与阀盖用螺栓连接，缠绕式垫片密封，优点是便于维修。 第三种：压力自紧式阀盖锻钢闸阀，按这种连接形式设计的阀门，其阀体与阀盖用螺蚊连接，内压自密封环密封，优点是内部压力越大，其密封性能越好。 锻钢闸阀安装使用说明： 1、安装在保温管道上的各类手动阀门，手柄均不得向下 2、安装位置、高度、进出口方向必须符合设计要求，连接应牢固紧密 3、锻钢闸阀安装前必须进行外观检查，阀门的铭牌应符合现行国家标准《通用阀门标志》GB 12220的规定。对于工作压力大于1.0 MPa 及在主干管上起到切断作用的阀门，安装前应进行强度和严密性能试验，合格后方准使用。强度试验时，试验压力为公称压力的1.5倍，持续时间不少于5min，阀门壳体、填料应无渗漏为合格。严密性试验时，试验压力为公称压力的1.1倍；试验压力在试验持续的时间应符合GB 50243标准要求，以阀瓣密封面无渗漏为合格。

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译文：
Forged steel valve for cut or connect the line of medium, use different materials, can be separately applied to water, steam, oil, nitric acid, acetic acid, oxidizing medium, urea and other various media. It has three kinds of body cover to connect the design form below First: Welding connection forged steel valve body covered by this form of connection design of the valve, the valve body and valve cover seal welded, the advantage of no external leak The second: forged steel valve body bolted cover, designed by this form of connection valve, the valve body and valve cover bolt connection, spiral wound gasket seal, the advantage of easy maintenance. The third: the pressure from tight bonnet forged steel valve, according to the design of the valve of this form of connection, the valve body and valve cover to connect with Lo mosquito, the internal pressure self-sealing ring seal, the greater the advantage of internal pressure, the better the performance of its sealing. Forged Gate Valve Installation instructions: 1, installed in various types of pipe insulation manual valve handle shall be down 2, the installation location, height, must meet the design requirements of the import and export orientation, the connection should firmly close 3, forged steel gate valve for visual inspection before installation, the valve plate should be consistent with existing national standards, "Universal Valve logo" GB 12220 requirements. The working pressure greater than 1.0 MPa and in the main pipe on the role played off valve, the installation should be carried out before the performance test the strength and tight, qualified prospective use of the rear. Strength test, the test pressure for the nominal pressure of 1.5 times the duration of not less than 5min, the valve housing, packing should be no leakage in compliance. Tightness test, the test pressure of 1.1 times nominal pressure; test the duration of the test pressure shall comply with GB 50243 standards, in order to flap valve sealing surface and no leakage to pass.