浅谈如何给控制阀选择电动执行器产品
how to choose the electric actuator product for control valve？
在日常工作中我们该如何来为一台阀门选用电动执行器产品?下面就让天蝶阀门有限公司给大家说一下吧！
in the daily work, how to choose a electric actuator product for a control valve? let the tandy valve co., ltd. give you a look!
在流程工业中控制阀主要用来控制工艺介质的流量、温度、压力和在设备中的液位等参数，选择阀门电动执行器时，除了考虑所调节的工艺介质变化对被控参数的影响外，还要考虑工艺介质特性，气态还是液态，单相流还是多相混合流、是否有腐蚀，介质的操作状态如温度、压力、流量、阀上下游两侧压差等因素的影响。
（罗托克电动执行器）
in the process industry, the control valve is mainly used to control the parameters such as flow rate, temperature, pressure, and liquid level in the equipment in the process medium. when selecting the valve electric actuator, in addition to considering the effect of the changed controlled process medium on the controlled parameter, it is also necessary to consider the characteristics of the process medium, it is gas or liquid, single-phase or multi-phase mixed flow, whether there is corrosion, the operating conditions of the medium such as temperature, pressure, flow, pressure difference between the upstream and downstream sides of the valve and other factors.
（dkj电动执行器）
比如黑水流量控制阀，由于黑水中含有固体颗粒，除了考虑工艺流量，温度、压力以及在阀门两侧压差大小这些参数外、还需要考虑黑水中的固体颗粒对阀内件冲刷的影响，考虑控制阀节流以后会不会出现闪蒸、气蚀现象，如果阀门前后压差太大，介质节流后发生闪蒸或气蚀，对阀门会产生很大的危害，这些因素都需要在阀门电动执行器设计选型中充分的考虑。
for example, the black water flow control valve, because the black water contains solid particles, in addition to considering the process flow, temperature, pressure, and the size of the pressure difference between the two sides of the valve, but also need to consider the impact of solid particles in black water on the valve interior erosion, considering the control valve after throttling will not occur flash steam and cavitation phenomenon, if the valve before and after pressure difference is too large, the media after throttling will not occur flash steam and cavitation, the valve will have a great deal of damage, these factors need to be in full consideration for the design and selection of valve electric actuator.
（qt电动执行器）
此外在电动执行器选择时还要考虑控制阀流量特性对所控制的工艺参数的影响，选择阀门的流量特性是等百分比、线性、还是快开型，对一些苛刻的特殊工况、开车工况，与正常流量比较，如果流量调节的范围很宽，就要求阀门有大的可调比特性。
in addition, when selecting the electric actuator, the influence of the flow characteristic of the control valve on the controlled process parameters must be considered. the flow characteristics of the valve are selected to be equal percentage, linear, or quick opening type, and for some severe special working conditions and driving conditions, compared with the normal flow, if the range of flow adjustment is very wide, the valve requires a large adjustable ratio characteristic.
设计人员在控制阀选型过程中，对阀门使用的过程条件充分了解后，要明确提出阀门的技术要求和参数，比如控制阀门的类型，像偏心旋转阀、直通阀、轴流阀、平衡式的笼式控制阀等，阀体、阀内件材质;阀体尺寸大小，连接形式、压力等级;阀门定位器、阀附件等要求，还会给出一些特定参数比如调节速度、阀门全开或全关时间、噪声等级等。
in the control valve selection process, with the full understanding of the valve using process conditions, designers should not only clearly specify the valve technical requirements and parameters, such as the type of control valve, like eccentric rotary valve, straight valve, axial flow valve, balanced cage control valve, etc.. the valve body, valve trim material; valve body size, connection form, pressure rating; valve positioner, valve accessories and other requirements, but also give some specific parameters such as adjusting speed, the valve fully open or fully closed time, noise level and so on.