With the cooperation of microcomputer, the flow can be adjusted and controlled in many sections without limit. It is a soft piston structure electrohydraulic valve with a wide range of applications and excellent constant flow and multi section control functions. Compared with diaphragm electrohydraulic valve, it has excellent linear control, adjustable constant speed response, low pressure drop at high flow rate, small flow rate, stable control of one liter per second, and constant flow function. It can solve the problem of overshoot and eliminate water hammer. And long life. High oil delivery accuracy. It is an advanced actuator that can automatically control the flow and flow rate of the conveying medium. It is suitable for use as an automatic control actuator in pipeline storage and transportation of petroleum, chemical, metallurgy, electricity, food, etc. It has been proved by the use of Sinopec and PetroChina oil depots that the valve has excellent performance, which solves the problems of severe water hammer, short diaphragm life, inaccurate measurement (no small flow) and other problems of domestic (imitation of foreign products) multi-function electrohydraulic valves. It is the first choice to replace imported products.