Liebherr expands mobile construction crane line

31 March 2021

Liebherr has launched the three-axle MK 73-3.1 mobile construction crane, designed for one-man operation.

It is the smallest crane of the MK range, which also includes the MK 88-4.1 and MK 140. It has a maximum lifting capacity of 6t, 2t lower than the other two models.

With a jib length of 38.5m, the MK 73-3.1 offers a jib head load capacity of 2,000kg with corresponding additional ballast. In a 45° luffed jib position, the crane reaches a lifting height of 51m and has a maximum lifting capacity of 2,800kg; up to 1850kg at the jib head. Three possible luffed jib positions ensure flexible operation.

Like all mobile construction cranes, this model is predestined to be used as a taxi-crane. Liebherr says it is ready for use in around ten minutes.  

The manufacturer highlights the MK 73-3.1’s compactness and manoeuvrability, which make it suitable for space-restricted construction sites. It has a total length of 13.8m, a width of 2.75m and a height of 4m. Despite being smaller than the other models in the range, the new model has the same features.

It operates electrically on site, either via site power supply or its integrated electric generator. “This ensures an extremely quiet and emission-free presence, which in turn is ideal for working at night and in noise-sensitive areas,” said Liebherr.

The small mobile construction crane is also designed for operation with 63 or 32 amps. “Working speed is in no way restricted when using the 32 amp option,” the manufacturer added.

The single-engine concept already used by the mobile cranes of sister company Liebherr-Werk Ehingen, has been adopted for the MK 73-3.1. The electric generator on the MK 73-3.1 mobile construction crane is only operated by the travel motor in the undercarriage. “The ECO mode also comes into play here,” the manufacturer added.

The new machine also features a number of assistance systems, including: an infinitely adjustable lift cabin; modern camera systems, with both load and undercarriage always in view; Micromove fine positioning mode.

Five steering programmes with active rear axle steering and half-sided support enable the crane to be used on particularly tight construction sites.

Optional features like the Load Plus load curve and reinforced trolley travel gear can further increase the crane’s performance. “This enables up to 50% heavier loads to be lifted in a 45° luffed position,” Liebherr said.