Crane and hydraulic system thereof

The present invention discloses a crane and a hydraulic system thereof. The hydraulic system comprises a pressure oil source, a hydraulic cylinder and a control valve set. The pressure oil source is used for providing pressure oil. The hydraulic cylinder comprises a rodless chamber and a rod chamber. The control valve set is provided in a fluid loop between the pressure oil source and the hydraulic cylinder, and is used for controlling operation pressure of the hydraulic cylinder and flow of the fluid in the fluid loop. The control valve set is a pile-up valve, the control valve comprises a reversing valve and a first throttle valve. The reversing valve is fluidly communicated with the rodless chamber of the hydraulic cylinder for forming a first working oil way, and is fluidly communicated with the rod chamber of the hydraulic cylinder for forming a second working oil way, thereby switching the pressure oil which is supplied from the pressure oil source for entering the rodless chamber of the hydraulic cylinder through the first working oil way or entering the rod chamber of the hydraulic cylinder through the second working oil way. The first throttle valve is provided in the first working oil way.