The invention provides a hydraulic energy-saving
system. The hydraulic energy-saving
system comprises a stretching and contracting oil cylinder and a main valve and furthermore comprises an oil supplementary valve; the stretching and contracting oil cylinder is a single-
piston-rod oil cylinder; the main valve is connected with the stretching and contracting oil cylinder, the main valve comprises a work oil opening A, a work oil opening B, an oil inlet P connected with a hydraulic oil source and an oil return opening T connected with an
oil tank; the work oil opening A is connected with a rodless cavity oil opening of the stretching and contracting oil cylinder (6), the work oil opening B is connected with a rod cavity oil opening of the stretching and contracting oil cylinder, the oil supplementary valve is connected between the hydraulic
oil tank and the rod cavity oil opening of the stretching and contracting oil cylinder, and one-way communication from the hydraulic
oil tank to a rod cavity of the stretching and contracting oil cylinder is achieved; and the main valve comprises an A-opening oil feeding throttling slot, an A-opening oil return throttling slot, a B-opening oil feeding throttling slot and a B-opening oil return throttling slot, and the B-opening oil feeding throttling slot comprises a throttling segment and an interception segment. The invention furthermore provides a reach
stacker. According to the hydraulic energy-saving
system provided by the invention, retraction of an arm frame is achieved through the
gravitational potential energy of a stretching and contracting arm, and system
energy consumption is lowered.