Patent ID: 7172082

Claim:
A mobile crane comprising: an undercarriage supported on axles having axle load limits; a superstructure mounted rotatably on the undercarriage; a main boom supported on the superstructure so that the main boom can rotate about a horizontal axis through a load plane, thereby having a variable rake, the main boom comprising a base box unit and a plurality of telescoping sections which can be extended from the base box unit to a maximum length of the main boom; a hydraulic luffing ram hinged to the superstructure and the base box unit for adjusting the rake of the main boom; and a lifting capacity increasing arrangement for increasing the lifting capacity of the main boom, the arrangement being permanently connected to the base box unit and having a weight which is included in a total weight of the main boom, the individual telescoping sections being arranged and dimensioned so that the total weight of the main boom does not exceed a maximum weight defined by the axle load limits, and so that a ratio of a top weight of the fully extended main boom, measured in a horizontal position of the main boom on an upper end of the main boom, to a base weight of the fully extended main boom, measured in a horizontal position of the main boom on a base end of the main boom, does not exceed 40:60.