Ring Check Valve??

An inspection of input voltage vs flow rate properties of a hydraulic servo valve Im impressing a triangular wave (frequency 0.01Hz amplitude +-10v) and plotting voltage and flow on an X Y graph. I have to set the main pressure so that the valve pressure fall at the flow rate when the input voltage is 10v (rated flow rate)is 2Bar.
Valve pressure fall=Ps-(Pa-Pb)-Pt,Ps:Main pressure,Pa:A port pressure
Pb:B port pressure,Pt:T port pressure
The different port placing, being no servo engineer I dont directly take the diagram connection a-b and t.
I have an inkling though about your question.
From the original1CheckValve
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