Spool Valves Allow Soft Unloading
Since control volumes in pilot circuits are typically small, the lower gain characteristics of spool valves produce a softer unload. To further extend the operating rate, Sun offers a "Soft Shift" option that adds an orifice in the valve’s armature to gain greater control of fluid displacement. Combining the benefits of a spool valve with the "Soft Shift" option extends shift times, which can reduce the hydraulic shock generated when unloading main-stage elements. Sun’s “Soft Shift” option is offered on all of its spool-type solenoid valves.