Valve iyi imagwiritsidwa ntchito potsegula cholowera ku hydraulic circuit (Valve nthawi zambiri imatsekedwa).
Spool ikangoyendetsedwa mwamakina, madzi ake amakhala opanda P kupita ku A. Atha kugwiritsidwa ntchito ngati:
a) kukhazikitsa kutsata kwa 2 actuators
b) monga mapeto a valavu ya sitiroko, kumene kutuluka kwake kumalumikizidwa ndi thanki.