Method for erecting an at least two-piece main boom for a lattice-boom crane and lattice-boom crane built accordingly

摘要

The present invention substantially relates to a method for erecting and disassembling an at least two-piece main boom for a lattice-boom crane. The erecting and disassembling procedure results in that the geometric kinematic properties of the main boom (1, 2) are used in such a manner that during the erecting and disassembling, the effective lever arm (1′) of the main boom (1, 2) is reduced. This results from the main boom (1, 2) being bent at the hinge point (A), at which at least two boom portions (1, 2) are connected to each other, and thus an angle position is produced between the two boom portions (1, 2). Further, the invention relates to a main boom (1, 2), which can be erected by the method as well as a lattice-boom crane having such an main boom (1, 2).