Does the shut-off valve come with a handwheel, and how should it be designed?

Whether a shut-off valve is equipped with a handwheel is usually determined by the process engineering team based on the frequency of operation and the installation location. Control system designers should determine the level of automation and the control methods based on the process requirements and operational conditions on site, to ensure that the shut-off valves can meet the process’s demands regarding operation speed and precision. .

There is debate regarding whether pneumatic valves need to be equipped with a handwheel mechanism. In some cases, as specified in the \"Specifications for the Selection and Design of Automated Instruments\" (HG/T 20507-2014), control valves without bypasses should be equipped with a handwheel mechanism. However, if a process safety interlock is used to control the emergency shut-off valve, a handwheel mechanism should not be provided. On the other hand, the \"Code for Design of Oil Storage Tanks\" (GB 50074-2014) requires that valves on process pipelines, whether electric or pneumatic, must have a manual operation function. This means these valves may need to be equipped with handwheels. The main function of the handwheel mechanism is to allow the operator to change the open or closed state of the valve by rotating the handwheel, thereby controlling the flow of fluid. In scenarios that require manual operation, this type of valve is particularly useful; for example, on the emergency shut-off valves of storage tanks such as liquefied hydrocarbon spheres, it may be necessary to provide on-site manual valve shutdown buttons or switches. In general, whether to equip the shut-off valve with a handwheel should be determined based on specific application requirements and safety regulations.