进口疏水阀选型必须提供疏水阀的疏水量也叫排水量(蒸汽消耗量)、疏水阀的工作压差、工作温度等工况参数，具体说明如下：
1.进口疏水阀的疏水量：选用疏水阀时，必须按设备每小时的耗汽量乘以选用倍率2-3倍为比较大凝结水量，来选择疏水阀的排水量。才能保证疏水阀在开车时能尽快排出凝结水，迅速提高加热设备的温度。疏水阀排放能量不够，会造成凝结水不能及时排出，降低加热设备的热效率。(当蒸汽加热设备刚开始送汽时，设备是冷的，内部充满空气，需要疏水阀把空气迅速排出，再排大量低温凝结水，使设备逐渐热起来，然后设备进入正常工作状态。由于开车时，大量空气和低温凝结水，较低的入口压力，使疏水阀超负荷运行，此时疏水阀要求比正常工作时的排水量大，所以按选用倍率2-3倍来选择疏水阀。)
1. Drain capacity of inlet drain valve: when selecting the drain valve, the water discharge of the drain valve must be selected by multiplying the steam consumption per hour of the equipment by the selection ratio of 2-3 times as the maximum condensation water volume. In order to ensure that the steam trap can discharge condensate as soon as possible during start-up, and the temperature of heating equipment can be increased rapidly. If the energy discharged from the steam trap is not enough, the condensate can not be discharged in time and the thermal efficiency of the heating equipment will be reduced. (when the steam heating equipment starts to supply steam, the equipment is cold and full of air inside. The steam trap is required to quickly exhaust the air, and then a large amount of low-temperature condensate water is discharged to make the equipment gradually warm up, and then the equipment enters the normal working state. Due to the large amount of air, low temperature condensate and low inlet pressure during start-up, the drain valve is overloaded. At this time, the drain valve is required to discharge more than normal operation. Therefore, the drain valve is selected according to the ratio of 2-3. )
2.进口疏水阀的工作压差：选用疏水阀时，不能以公称压力选疏水阀，因为公称压力只能表示疏水阀体壳承受压力等级，疏水阀公称压力与工作压力的差别很大。所以要根据工作压差来选择疏水阀的排水量。工作压差是指疏水阀前的工作压力减去疏水阀出口背压的差值。疏水阀后背压计算方式是：(当疏水阀后凝结水排入大气时，疏水阀的出口背压为零。如果把疏水阀排出的冷凝水集中回收，此时，疏水阀的出口背压是回水管的阻力、回水管抬升高度、二次蒸发器(回水箱)内压力三者之和。)
2. Working pressure difference of imported drain valve: when selecting the drain valve, it is not allowed to select the drain valve according to the nominal pressure, because the nominal pressure can only indicate the pressure level of the drain valve body shell, and there is a big difference between the nominal pressure and the working pressure of the drain valve. Therefore, according to the working pressure difference to select the drainage valve. The working pressure difference refers to the difference between the working pressure in front of the steam trap minus the back pressure at the outlet of the steam trap. The back pressure calculation method behind the trap is as follows: (when the condensate behind the trap is discharged into the atmosphere, the outlet back pressure of the trap is zero. If the condensate water discharged from the steam trap is recycled in a centralized way, the outlet back pressure of the drain valve is the sum of the resistance of the return pipe, the lifting height of the return pipe and the pressure in the secondary evaporator (return water tank). )
3.机械型疏水阀的阀座号：机械型疏水阀按不同的工作压差段，分成多种规格阀座孔径的“阀座号”，每个工作压差段与“阀座号”组成一条坐标曲线的排水量，不同“阀座号”的疏水量有很大差别。机械型疏水阀应根据工艺条件的比较高工作压差和比较大排水量两者相对应的坐标曲线来选合适的“阀座号”。不能以公称压力来定“阀座号”，如果选错“阀座号”，有可能出现疏水阀不工作或设备存水，影响设备正常运行。
4.疏水阀的工作温度：选用疏水阀时，要根据管道蒸汽比较高温度来选择能满足工艺条件要求的疏水阀。管道蒸汽比较高温度超过公称压力相对应的饱和蒸汽温度称为过热蒸汽，在过热蒸汽管道选择疏水阀时，应选用高温高压过热蒸汽专用疏水阀。
5.进口疏水阀的连接尺寸：疏水阀的工艺条件决定以后，根据疏水阀前后的工作压差、疏水量和“阀座号”，按疏水阀制造厂家的技术参数来选择疏水阀的规格尺寸。(不能按设备连接尺寸随便选配同样尺寸的疏水阀，疏水阀的连接口径不能代表疏水量的大小，同一种口径的疏水阀，疏水能力可能差别很大；所以选用疏水阀时必须根据设备的工艺条件，参照疏水阀制造厂家提供的参数来选配疏水阀才是正确的选择
以上就是德国洛克技术人员为大家讲解的有关进口疏水阀的相关资料。如需了解更多有关阀门知识请登入德国洛克官网或者来电咨询：138234185985
