The new MK 73-3.1 mobile construction crane is the smallest in Liebherr’s mobile construction crane family and complements the crane series comprising the MK 88-4.1 and MK 140. The compact 3-axle crane is the answer to market demands for a small, compact and agile mobile construction crane that is fast and flexible in operation.

Mobile construction cranes are predestined to be used as taxi cranes and, with this in mind, the MK 73 3.1 is also designed for one-man operation. This crane is ready for use in around 10 minutes. Additional transport vehicles are not required for the crane. The electrically operated crane can be supplied with site power or powered by its integrated generator. The single-engine concept, familiar from Liebherr’s mobile cranes, and its ECOmode feature ensure reliable travel and economical operation on site.

For the crane, Liebherr has chosen proven technology in an extremely compact form. The small mobile construction crane combines all the features of its big brother, the MK 88-4.1. With a total length of 13.80 m, a width of 2.75 m and a height of 4.0 m, it is impressively compact and, as a result, extremely easy to manoeuvre. It offers a 6-tonne maximum load capacity.

Long reach options

To meet the typical demands of densely built-up inner city construction sites with projecting edges, this latest mobile construction crane has been designed with long reaches in mind. With a jib length of 38.5 m, it offers a jib head load capacity of 2,000 kg with corresponding additional ballast. In a 45-degree luffed jib position, the crane reaches a lifting height of 51 m and has a maximum lifting capacity of 2,800 kg; up to 1850 kg at the jib head. Engineers have placed strong emphasis on a design with a consistently high maximum load capacity in all luffed jib positions. Three possible luffed jib positions ensure flexible operation.

Electric crane operation

Like its big brothers, the MK 73-3.1 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. 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.

Extensive features

Similar to the other mobile construction cranes in the series, the crane operator is supported by diverse assistance systems. Highlights include an infinitely adjustable lift cabin and modern camera systems?–?both load and undercarriage are always in view. Assistance systems such as the Micromove fine positioning mode ensure precise load handling. Five steering programmes with active rear axle steering and half-sided support enable the crane to be used on particularly tight construction sites.

Additional options such as the Load Plus load curve and reinforced trolley travel gear further increase the crane’s performance. This enables up to 50 per cent heavier loads to be lifted in a 45 degree luffed position.

Single-engine concept

The single-engine concept already used by the mobile cranes of sister company Liebherr-Werk Ehingen GmbH, has been adopted for the MK 73-3.1. This concept makes operation even more economical: 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.

Liebherr has packed all the technology features of its big brothers into this small mobile construction crane; impressive manoeuvrability and flexibility combined with reliability ensure an efficient, modern addition to any crane fleet.