进口蒸汽电磁阀是由副阀和主阀两大部件构成的先导式二次开阀的电磁阀。是靠副阀的启闭来控制主阀的通断。根据断电时所处开关状态的不同，可分为常闭电磁阀和常开电磁阀。

Steam electromagnetic valve is made by the Deputy valve and main valve consisting of two parts guide type two opening valve electromagnetic valve. On the side the valves open and close to the main control valve on-off. According to the power which the switch state is different, can be divided into normally closed solenoid valve and the normally open solenoid

    
进口蒸汽常闭电磁阀在断电常位时，副阀口封闭，主阀呈断路，当电讯号进入导阀线圈时，活动铁芯受电磁力作用吸上打开副阀口，主阀阀杯内压力迅速消失，介质压力将主阀阀杯托上，开启主阀口，工作介质硬可流通。但当电讯号消失时，活动铁芯复位，封闭住副阀口，工作介质自平衡孔进入阀杯内，当压力趋于平衡时，靠主阀弹簧、阀杯自重及介质压力使阀杯下移，严密封住主阀口，阀又呈关闭状态。

Inlet steam normally closed solenoid valve in power often position, vice valve closed, the main valve is open, when the electrical signal into the pilot valve coil, core activities by electromagnetic force sucking on open side valve, the main valve pressure in the cup quickly disappeared, medium pressure of the main valve cup holder, open the main valve port, the working medium hard negotiable. But when the signal disappears, the movable iron core reset, vice valve closed, the working medium self balancing hole into the valve cup, when the pressure is balanced, rely on the main valve spring, valve cup weight and medium pressure causes the valve cup downward, tight seal main valve port, valve was closed.

    
进口蒸汽常开电磁阀在断电常位时，由弹簧作用，副阀口打开，主阀流通。当电讯号进入副阀线圈时，活动铁芯受电磁作用吸下，副阀口封闭，工作介质经平衡孔进入阀杯内，当压力趋于平衡时，靠主阀弹簧、阀杯自重及介质压力使阀杯下移，严密封主阀口，阀门呈关闭状态。当主阀断电时，电磁力消失，副阀打开，主阀杯内压力迅速消失，介质压力将主阀阀杯托上，开启主阀口，介质流通，阀呈开启状态。

Steam electromagnetic valve in power down often when, by spring action, the Deputy valve port opened, the main valve flow. When the signal into the auxiliary valve coil, core activities by electromagnetism suction, vice valve closed, working medium through the balance hole into the valve cup, when the pressure is balanced, rely on the main valve spring, valve cup weight and medium pressure causes the valve cup downward, tightly sealed and the main valve port, valve is closed state. When the main valve is powered off, the electromagnetic force disappears, the Deputy valve is opened, the main valve pressure in the cup quickly disappeared, medium pressure of the main valve cup holder, open the main valve port, medium circulation, valve is in an open state.