译文：
一：适用性 管路中的流体必须和选用的电磁阀系列型号中标定的介质一致。 流体的温度必须小于选用电磁阀的标定温度。 电磁阀允许液体粘度一般在20CST以下，大于20CST应注明。 工作压差，管路{zg}压差在小于0.04MPa时应选用如ZS,2W,ZQDF,ZCM系列等直动式和分步直动式；{zd1}工作压差大于0.04MPa时可选用先导式（压差式）电磁阀；{zg}工作压差应小于电磁阀的{zd0}标定压力；一般电磁阀都是单向工作，因此要注意是否有反压差，如有安装止回阀。 流体清洁度不高时应在电磁阀前安装过滤器，一般电磁 阀对介质要求清洁度要好。 注意流量孔径和接管口径；电磁阀一般只有开关两位控制；条件允许请安装旁路管，便于维修；有水锤现象时要定制电磁阀的开闭时间调节。 注意环境温度对电磁阀的影响 电源电流和消耗功率应根据输出容量选取，电源电压一般允许±10%左右，必须注意交流起动时VA值较高。 二、可靠性 电磁阀分为常闭和常开二种；一般选用常闭型，通电打开，断电关闭；但在开启时间很长关闭时很短时要选用常开型了。 寿命试验，工厂一般属于型式试验项目，确切地说我国还没有电磁阀的专业标准，因此选用电磁阀厂家时慎重。 动作时间很短频率较高时一般选取直动式，大口径选用快速系列。 三、安全性 一般电磁阀不防水，在条件不允许时请选用防水型，工厂可以定做。 电磁阀的{zg}标定公称压力一定要超过管路内的{zg}压力，否则使用寿命会缩短或产生其它意外情况。 有腐蚀性液体的应选用全不锈钢型，强腐蚀性流体宜选用塑料王（SLF）电磁阀。 爆炸性环境必须选用相应的防爆产品。 四、经济性 有很多电磁阀可以通用，但在能满足以上三点的基础上应选用最经济的产品。 电磁阀的结构原理 一：直动式电磁阀 有常闭型和常开型二种。常闭型断电时呈关闭状态，当线圈通电时产生电磁力，使动铁芯克服弹簧力同静铁芯吸合直接开启阀，介质呈通路；当线圈断电时电磁力消失，动铁芯在弹簧力的作用下复位，直接关闭阀口，介质不通。结构简单，动作可靠，在零压差和微真空下正常工作。常开型正好相反。如小于φ6流量通径的电磁阀。 二、分步直动式电磁阀 该阀采用一次开阀和二次开阀连在一体，主阀和导阀分步使电磁力和压差直接开启主阀口。当线圈通电时，产生电磁力使动铁芯和静铁芯吸合，导阀口开启而导阀口设在主阀口上，且动铁芯与主阀芯连在一起，此时主阀上腔的压力通过导阀口卸荷，在压力差和电磁力的同时作用下使主阀芯向上运动，开启主阀介质流通。当线圈断电时电磁力消失，此时动铁芯在自重和弹簧力的作用下关闭导阀孔，此时介质在平衡孔中进入主阀芯上腔，使上腔压力升高，此时在弹簧复位和压力的作用下关闭主阀，介质断流。结构合理，动作可靠，在零压差时工作也可靠。如：ZQDF，ZS，2W等。 三、间接先导式电磁阀 该系列电磁阀由先导阀和主阀芯联系着形成通道组合而成；常闭型在未通电时，呈关闭状态。当线圈通电时，产生的磁力使动铁芯和静铁芯吸合，导阀口打开，介质流向出口，此时主阀芯上腔压力减少，低于进口侧的压力，形成压差克服弹簧阻力而随之向上运动，达到开启主阀口的目的，介质流通。当线圈断电时，磁力消失，动铁芯在弹簧力作用下复位关闭先导口，此时介质从平衡孔流入，主阀芯上腔压力增大，并在弹簧力的作用下向下运动，关闭主阀口。常开式原理正好相反。如：SLA，DF（φ15以上口径），ZCZ等。 来源：慧聪网泵阀行业频道

“ Selection of valve and introduction on knowledge of its structure ”,是由提供的国际阀门新闻，译文仅供参考。另外，中国电磁阀网还提供相关产品搜索：、、、、等。

原文：
1: Applicability Fluid pipe valve must be selected in the calibration of medium range model consensus. Fluid temperature must be less than the calibration temperature selection valve. Solenoid valve to allow liquid viscosity generally 20CST less than 20CST should be marked. Working pressure, maximum pressure pipeline should be used in less than 0.04MPa as ZS, 2W, ZQDF, ZCM series and direct-action direct-action step; minimum working pressure greater than 0.04MPa may use Pilot (Pressure Differential) electromagnetic valve; maximum working pressure should be less than the maximum calibration pressure solenoid valve; generally one-way valve is working, so pay attention to whether there is anti-pressure, if installed check valve. Fluid cleanliness is not high solenoid valve should be installed before the filter, the general electromagnetic Valve on the media demands better cleanliness. Note flow aperture and take over the aperture; solenoid valve generally only two control switches; conditions allow, install bypass pipes, easy maintenance; a water hammer phenomenon to customize the opening and closing time of valve adjustment. Pay attention to environmental impact of temperature on the electromagnetic valve Supply current and power consumption should be selected according to the output capacity of the power supply voltage ± 10% around the general permit, must pay attention to when starting the exchange value of the higher VA. Second, reliability Solenoid valve normally closed and normally open divided into two; generally used in the normally closed, power open, power off; but in a very long time to open a very short time to close the normally open type of use. Life testing, factory type test items are generally, not specifically our professional standards solenoid valve, so use caution when solenoid valve manufacturers. Action is very short at high frequencies are usually selected straight acting, rapid series of large-caliber selection. Third, security General solenoid valve is not waterproof, when the conditions are not allowed to use water when you type, the factory can be customized. The maximum calibration nominal pressure solenoid valve must be more than the maximum pressure within the pipe, otherwise life will be shortened or produce other surprises. Corrosive liquids should be used all stainless steel type, strong corrosive fluids should use plastic Wang (SLF) solenoid valve. Explosive environment must use the appropriate explosion-proof products. Fourth, economy There are many solenoid valve can be generic, but meet the above three points should be chosen based on the most economical product. Structural principle of electromagnetic valve 1: Direct Action Solenoid Valve Are normally closed and normally open type two. Normally closed when power was turned off, when the electromagnetic force generated when the coil power, so moving core to overcome the spring force directly with the static pull open the valve core, medium was access; When the coil power disappear when the electromagnetic force, an iron core under the action of the spring force reduction, direct closure of valve port, media barrier. Simple structure and reliability, at zero pressure and micro-vacuum work. Normally open type just the opposite. If less than φ6 flow path of the solenoid valve. Second, step-type solenoid valve direct-acting The valve is an open valve and open valve connected to the second one, the main valve and valve guide step by step so that the electromagnetic force and the pressure directly open the main valve port. When the coils, the electromagnetic force to moving core and static core pull, pilot valve open while the pilot valve mouth port located on the main valve port, and the moving core and the main spool linked, then the main valve the pressure chamber through the pilot valve port of unloading, the pressure difference and the effect of electromagnetic forces while the main spool to move upwards, open the main valve medium flow. When the coil power disappear when the electromagnetic force, this time moving core in the role of gravity and spring force to shut down pilot valve hole, then the balance hole in the medium into the main valve on the chamber, so that the chamber pressure increases, at this time In the spring under the pressure reset and close the main valve, medium stop. Reasonable structure, reliable action, when the work at zero pressure and reliable. Such as: ZQDF, ZS, 2W, etc.. Third, indirect Pilot solenoid valve This series solenoid valve by the pilot valve and main valve connected with the formation of channel combinations; Normal Closed time, without power, was switched off. When the coils, the magnetic force generated by moving core and static iron core to pull, guide valve port open, medium flow to the export, then the main valve on the chamber pressure decreased, the pressure below the import side, the formation of pressure to overcome the spring resistance and the resulting upward movement, to open the main valve port of purpose, medium flow. When the coil power, the magnetic force disappears, moving core in the spring force reduction and closure of the pilot under the mouth, this time from the balance hole into the medium, the main valve on the chamber pressure, and under the action of the spring force downward, close the main valve port. Often the opposite of open principles. Such as: SLA, DF (φ15 above caliber), ZCZ so. Source: HC network Pump Industry Channels