Liebherr has formally launched its latest mobile self-erecting tower crane in end March 2021 – the three axle, six tonne MK73 3.1 – which is targeted at urban taxi crane applications.
The maximum jib length is 38.5 metres with a capacity of up to two tonnes when equipped with additional ballast. In can also luff up to 45 degrees above horizontal to reach a maximum lifting height of 51 metres with a capacity of up to 2,800kg – or 1,850 kg at the jib tip. It also offers two intermediate luffing angles.
Designed as a true one man operation the company says it can be ready to start lifting just 10 minutes after arriving on site. The crane superstructure is entirely electric powered and operated either by the onboard generator or an onsite mains power outlet – either 63 or 32 amps. The company says that operating speeds are not affected when using the 32 amp option. The carrier engine feature’s Liebherr’s ECOmode system for greater energy efficiency and lower emissions.
The new three axle is compact with an overall length of 13.8 metres, an overall width of 2.75 metres and an overall height four metres, yet maintains all of the features of the MK 88-4.1. Other features include a range of driver assist systems, such as Micromove fine positioning mode for precise load handling, and it also includes five steering programmes with active rear axle steering and ‘half sided support’ for work on particularly tight construction sites.
As with the two larger models the crane cab can operate at any tower height. New camera systems always keep both load and chassis in view. Options include the ‘Load Plus’ load chart and reinforced trolley travel gear which are said to allow up to 50 percent increases in loads to be lifted in a 45 degree luffed position.