With scientific design, beautiful appearance, the craneis superior in quality, reasonable in price, safe and reliable inoperation, and easy to maintain and repair. It is an idealconstruction machine for construction enterprises. The machine hasfour kinds of work structures: lifting, circumgyrating, variableranges, and top lifting. The four structures can work incombination as well as independently so as to improve workefficiency. The top lifting structure is used to increase theheight of the tower or lower the tower. The lifting structure makesuse of tri-speed motor, with three kinds of speeds: quick,intermediate and slow positioning. For circumgyrating, wire windingmotor speed-adjusting or double-speed motor speed-adjusting can beselected according to specific requirement so as to satisfydifferent demands. The lifting arm can rotate 540º to the left andright. The circumgyrating and range adjusting are agile andreliable, and the hoisting positioning is accurate. Thus the cranecan satisfy the need for vertical and horizontal transportation inconstruction operation.