What are pneumatic valve manual controller

the operating pneumatic valve, manual controller to people's physical strength and the ability to locate. Generally involve manual controller switch condition, and don't need high accuracy of the working condition of simple throttling or immediate feedback. In the third chapter talked about most of the manual pneumatic valve adopts manual controller. What are the advantages of manual controller with his mechanical simplicity - — Very few moving parts and no seal leakage caused by air chamber and failure. People to manipulate a unit ( For example the handwheel or lever) And make the pneumatic valves open and close or, in the middle of a trip. Simplicity means easier for maintenance of the structure, maintenance and removal. Manual controller disadvantage is that the response is slow, because the response depends on the people operating openhanded controller - — He sometimes, in some cases, will take some time. Need to turn to, for example, a linear handwheel or more revolutions to close an in schedule of pneumatic valves, and people have to cope with the fast arrive take manual pneumatic valve by pneumatic valve's journey time increased the response delay. If you need the throttle position ( Formed in the middle of the position) 。 Pneumatic valve position depends on the regulation of the controller, the controller of the adjusting range is very big. Under certain conditions these is not a problem, but over the years when the system requires more accurate, use manual controller to determine for the pneumatic valve throttle point is difficult.