? Automatic control of engine?s rotary speed for energy saving; ? Open-type hydraulic system with the fully hydraulic steering, the electrohydraulic cushion, and the differential pressure response, which provides high reliability and slight steering shocking; ? The pumping volume reaches 140m3/h, and the stepless control is adopted to meet various working conditions; ? Automatic retraction of concrete piston, which facilitates the checking and the replacing; ? The text display is adopted to show the operation parameters and the fault types. Also the multiple automatic protection system is equipped.