Pressure at ② overcomers the spring-bias poppet and allows free flow ②to③;
Flow in the opposite direction from ③to② is blocked by the poppet.
The cartridge has a 3:1 pilot ratio,meaning that at least one-third of the load pressure held at ③ is required at(T)to open the valve.
![Hydraulic Operated Check Valves(Ball-type) Power unit accessoriesPC08-30 from China supplier](/public/media/LazyImage_placeholder.09bec84d.svg)