Abstract: Based on the ANSYS Workbench platform,influence of the super-lift system and geometric parameters influence on the critical lifting capacity of the telescopic boom is studied.It is proved that super-lift system can be installed at a reasonable position and angle of the super-lift mast is expanded properly will increase critical lifting capacity of the telescopic boom.The super-lift also may become a load to decrease the critical lifting capacity.The critical lifting capacity increases first and then decreases with the increase of angle φ of the super-lift mast.The critical lifting capacity gradually decreases first and then increases rapidly with the increase of length H of the super-lift mast.When the length of super-lift mast reaches a certain length,the critical lifting capacity enhancing effect is not obvious with the continuing increase.The critical lifting capacity increases with the increase of distance L between the hinge point of the super-lift mast and the telescopic boom to the basic jib root,which means that it is most favorable that the super-lift mast is mounted near the base end of the basic jib.

Key words: ANSYS Workbench software, super-lift system, telescopic boom, buckling analysis, critical lifting capacity