The pressure reducing rotary valve is a pressure control valve that reduces the outlet pressure (secondary pressure) to be lower than the inlet pressure (primary pressure). It is widely used in the clamping systems, lubrication systems, and control systems of various hydraulic equipment. Additionally, when the pressure of the mixed oil fluid is unstable, inserting a pressure reducing rotary valve into the circuit can achieve a stable lower pressure. Depending on the controlled pressure of the pressure reducing rotary valve, it can be categorized into fixed-value output, fixed-difference, and fixed-ratio pressure reducing rotary valves.