The manual valve actuators are found in many industrial applications. The main reason for this is the fact that they do not need any external power sources to be able to move the valve to a desired position. They take advantage of a chainwheel, lever, handwheel or any other suitable detachable mechanism that is capable of driving a train of gears whose arrangement results into a higher torque output. The mechanism that is used is ideal and very efficient. There are numerous manual valve actuators that rely on worm gears. These are mechanical devices that are capable of transmitting motion between right angle axes that do not intersect.
There are many benefits of using the manual valve actuators. The main advantages include the cheap price, reliability and the fact that you will not have to look for a power source. They are usually designed in a self-contained manner. Their simplicity makes them easy to maintain. The motion that they use to open and close the valve is the same and it is therefore easy to notice any errors or irregularities. The only disadvantage with these actuators is that they are not automated systems; this means that you will have to control them manually every time.
There are different types of valves that can utilize the actuators. The valves are selected depending on the nature of application. The valves have different motions that achieve different objectives. The rotary motion valves are able to rotate through a 90 degrees turn to open or close the valve. The element that is used to close the valve is usually an ellipse or a disc that rotates about the angular shaft. There are several examples of this valve including the butterfly, the ball and the multi-turn valves. There are also the linear motion valves. These are valves that possess a sliding stem that has been designed to either close or open the element. The valve stem might rise during the rotation or without the rotation depending on the design. The closing element that is used can be either a disk or a plug that is slid down or pushed against an orifice. Some of the examples of linear motion valves are diaphragm, gate, globe and angle valves. The manual valve actuators can be used in most of these valves depending on their applications. These actuators can save the industry a lot of money especially when they are needed in huge numbers.