Introduction to the working principle of tubular one-way valve

When the hydraulic pressure produced by the pressure oil in the A chamber overcomes the hydraulic pressure and spring force and frictional resistance produced by the pressure oil in the B chamber on the valve core, the valve core opens and the oil flows from the A chamber to the B chamber, which is called positive flow. When the pressure oil flows from the B chamber, the spring force and the oil pressure in the B chamber act together to make the valve core press tightly. On the seat, the oil flow is cut off, called reverse cut-off, as shown in the figure. Thus, the opening conditions of the one-way valve are as follows:
PA-A chamber pressure (Pa) in the formula;
PB-B cavity pressure (Pa);
Ft - spring force (N);
Ff - Friction resistance (N) acting on the valve core;
W - Valve Center Gravity (N) (only considered in vertical installation, negligible in most cases);

A - Area of seat orifice (m2).