Still don’t know what a control valve is after reading this?

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Hi, it’s your industrial control assistant, Xiao Yang, back again. The little piece of knowledge I bring you today is about understanding control valves. Hurry up and get the small stools ready; let’s enjoy the fun of learning together. Control valves come in various types of actuators, and today we will mainly focus on pneumatic actuators. Pneumatic actuators fall into two main categories: air-operated open type (corresponding to the Fisher667 series) and air-operated closed type (corresponding to the Fisher657 series). The schematic diagram for the air-operated open type is as follows: the schematic diagram for the air-operated closed type is as follows. The same model is available in two versions – with a handwheel and without a handwheel; in all cases, the handwheel on these products is of the top-mounted type. The schematic is as follows: How are control valves classified? In simple terms, control valves are divided into linear stroke control valves, ball valves, butterfly valves, gate valves, and on-off valves. Straight-through control valves are divided into: single-seat, cage-type, and flange RF-welded BWE single-seat control valves. The corresponding Fisher model numbers for these are EZ, ES, and HPAS – three main categories. The corresponding Fisher model numbers for cage-type control valves are ETED and HPT – also three main categories. Control valve accessories are categorized as follows: sealing components, and the metal internals of the control valve. Sealing components include packing assemblies, valve body sealing components, and spool sealing components (spool sealing components are only available in cage-type valves). The metal internals of a control valve include the spool, seat, stem, and cage (a cage is only present in cage-type valves). An example diagram of a single-seat control valve is shown below; an example diagram of a cage-type control valve is shown below as well. That’s all for today. If you have anything you’d like to discuss or learn more about, feel free to leave a message.