Mobile crane

Mobile crane, comprising a boom which is mounted in a manner pivotable about a horizontal pivot axis, a hydraulic luffing cylinder, by means of which the boom can be luffed up and down about the pivot axis, a hydraulic control block for controlling the luffing cylinder, a first safety valve, which is connected between the control block and the luffing cylinder and is configured to seal off a load-bearing cylinder chamber of the luffing cylinder in a blocking position,

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• a second safety valve, which is connected in series between the first safety valve and the control block and is configured to seal off the load-bearing cylinder chamber of the luffing cylinder in the blocking position, and a hydraulic damping device, via which pitching vibrations of the crane can be damped by the boom when the crane is moved, and which comprises a hydraulic accumulator and a first valve, wherein the first valve connects the hydraulic accumulator to a connection line between the first and second safety valves in a first switching position and disconnects the hydraulic accumulator from the connection line in a second switching position, wherein the second safety valve is hydraulically-controllable and comprises a control port which is connected to a control valve via a hydraulic control line, wherein the control valve is electrically controllable and/or position-monitored by means of a position sensor.