Gauge control valve setting handwheel

The handwheel mechanism shall meet the following requirements: 1. A handwheel mechanism shall be provided for control valves that do not have a bypass. 2 The process production safety interlock, which is used to control the emergency shut-off valve, shall not be equipped with a handwheel mechanism. 3 Handwheels should not be used for the mechanical positioning of valves.

I. Principles for setting the handwheel: 1. The valve does not have a bypass. 2. At the request of the client. II. Design requirements for handwheels: 1. The handwheel should be available in top-mounted or side-mounted versions, capable of being locked; it should be driven by a screw or gears, and ideally it should allow for continuous operation through an integrated clutch mechanism. 2. The handwheel should indicate the direction in which the valve opens and closes. 3. When using a cylinder actuator, the cylinder should include an air circuit bypass valve. 4. For control valves, the handwheel should allow the valve stem to move in two directions. 5. The neutral position of the handwheel should be clearly marked. 6. The operation of the handwheel should not induce friction on the actuator. 7. The clutch mechanism of the angular travel valve handwheel should be designed so as not to change the valve position when the handwheel is engaged. II. Precautions for using the handwheel: 1. The handwheel should usually be in neutral position and locked. 2. The handwheel should not be used as a limit for the valve’s travel. Everyone, add more.

The use of hand wheels has its advantages and disadvantages; one of the disadvantages is that it increases the cost of control valves and complicates the structure of the actuator. Another example: if foreign objects get stuck in the valve, the operator sees that the valve cannot be closed completely. Thinking that there must be a problem with the instrumentation, they try to force it shut using the handwheel, and as a result, both the valve stem and the seat are damaged. Since a handwheel is to be used, it’s better to consider installing a bypass after all. (In some situations, setting up a bypass is useless as the material blocks the bypass.)