The invention discloses two-stage
hydraulic cylinder with multi-layer core tubes and a crane, and belongs to the technical field of
engineering machinery. The two-stage
hydraulic cylinder with the multi-layer core tubes comprises a
piston rod head, an inner telescopic core tube, a sleeve, a
piston rod
assembly, a first-stage cylinder
barrel and a second-stage cylinder
barrel, wherein one end of the inner telescopic core tube, one end of the sleeve and one end of the
piston rod
assembly are connected to the
piston rod head; the first-stage cylinder
barrel is provided with an outer telescopic core tube, multiple working oil ports are formed in the
piston rod head, the first-stage cylinder barrel is arranged in the second-stage cylinder barrel, and the first-stage cylinder barrel is providedwith an outer cavity connected to the sleeve and the
piston rod assembly and an inner cavity connected to the inner telescopic core tube; and the working oil ports can independently control extensionand retraction of the first-stage cylinder barrel and the second-stage cylinder barrel. According to the two-stage
hydraulic cylinder with multi-layer core tubes and the crane, all stages of the cylinders can be independently controlled and are not limited in sequence, various working conditions of the device are met, the weight of an oil cylinder is greatly reduced, the performance of a suspension arm and the stability of the whole
machine are improved, the arrangement space is saved, and arrangement and optimization of a
rope arrangement mechanism are facilitated.