A valve operating element is a mechanism that transfers torque to the valve, this could be a handwheel, lever, extension spindle, gearbox/actuator or interlock. These options are interchangeable across the T-T Flow range but may not fit valves from other manufacturers.
Handwheels are wheels attached to the valve's stem, allowing for manual operation via wheel rotation. They are usually designed for operating and adjusting smaller valves that do not require fine control or rapid opening/closing.
Levers use manual, linear or rotational force to operate the valve, ideal for larger valves, those requiring fast opening/closing and those that require a large force than a handwheel can provide.
Extension spindles extend the length of the valve stem to allow for the operation of valves in deep, confined or otherwise difficult-to-access locations.
Gearboxes (also known as actuators) provide automated valve opening, closing and adjusting via manual or motor-driven input. Similarly to extension spindles, gearboxes can provide operators with a greater degree of safety by enabling remote operation.