Abstract: A crane includes a crane pillar supported rotatably about an axis, and a radial bearing for supporting the rotatable crane pillar in a crane base. The radial bearing is lower in an installation position of the crane pillar, and an upper radial bearing likewise supports the crane pillar in the crane base. The upper radial bearing is spaced apart at a distance from the lower radial bearing along the axis. At least one chamber can be filled with oil and is provided for lubricating the upper radial bearing. A drive unit is provided for the crane pillar, and the drive unit drives the crane pillar between the upper radial bearing and the lower radial bearing. A driven region on the crane pillar is lubricated with oil by the chamber that can be filled with oil.

Abstract: A crane includes a crane pillar supported rotatably about an axis, and a radial bearing for supporting the rotatable crane pillar in a base. The radial bearing is lower in an installation position of the crane pillar, and an upper radial bearing likewise supports the crane pillar in the base. The upper radial bearing is at a distance from the lower radial bearing along the axis. At least one chamber can be filled with oil and is provided for lubricating the upper radial bearing. A drive unit is provided for the crane pillar, and the drive unit drives the crane pillar between the upper radial bearing and the lower radial bearing. A driven region on the crane pillar is lubricated with oil by the chamber that can be filled with oil.

Abstract: The invention relates to a method for signaling the danger of a crane tipping, comprising at least three alarm systems for signaling tipping warnings using a respective safety programme. At least one measurement value is obtained from the crane, at least two alarm systems for signaling the tipping warning are selected in accordance with the at least one measurement value and if a warning of tipping is signaled by at least two of the at least two selected alarm signals, a tipping warning is signalled.

Abstract: The invention relates to a method for securing the position of a crane with at least two support legs for supporting said crane on surfaces. At least one threshold is entered for the support legs, and movements which increase the supporting force are blocked if at least one threshold is exceeded by a current supporting force, the thresholds for each of the support legs being entered individually and/or for subgroups of support legs.

Abstract: A vehicle crane—in particular an articulated-arm crane—includes a lifting arm and one or more articulated arms, and the geometry of the crane arms can be changed with respect to one another. A load cable can be guided or is guided on the crane arms. A compensation device allows the tension in the load cable to be controlled or regulated upon a change in the geometry of the crane arms with respect to one another.