At ConExpo, Liebherr unveiled the LTM 1160-5.2, a 190-ton mobile crane on a five-axle chassis. Compared to its predecessor, the LTM 1160-5.1, the LTM 1160-5.2 has a 20-25% increase in load capacity even though it uses the same 203-ft. telescopic boom. Vehicle width has been reduced from 9’10’’ to 9’0”, which makes it easier to drive on public roads and through constricted sites.
One of the most notable features on the LTM 1160-5.2 is that the superstructure is powered by a single engine in the crane chassis using a mechanical shaft, rather than the twin-engine concept normally used on cranes in this class. This is the second five-axle crane model to feature the single-engine drive concept, which Liebherr first presented at Bauma 2013 on the LTM 1300-6.2.
Gear shafts are routed from the distributor gear in the crane chassis via two mitre gears through the center of the slewing ring to the pump distributor gear in the superstructure.
A Tier 4 Final, six-cylinder Liebherr diesel engine develops 544 hp at 1900 rpm and torque of 2,516 Nm at 1350 rpm. Force is transferred to the crane axles via the 12-speed ZF-AS Tronic gears. The intarder, a zero-wear hydrodynamic brake integrated in the gearbox, acts as a retarder. In addition a Telma eddy current brake is available as an option.
The mechanical shaft ensures a high efficiency level, and low engine speeds in the chassis engine provide sufficient power for crane work. Benefits of removing the separate superstructure engine include reducer maintenance work and weight. The omitted weight can be used for load-bearing components, thus increasing the crane’s load capacity.