Economical all-rounder on four axles: the new Liebherr LTM 1090-4.2

Liebherr presents an economical all-rounder on four axles at the Intermat in Paris: the new LTM 1090-4.2 mobile crane combines mobility, performance and economy in a superb package.

Liebherr recently launched an economical all-rounder on four axles: the new LTM 1090-4.2 mobile crane combines mobility, performance and economy in a superb package.

The new 90-tonne crane from Liebherr is suitable for global economical mobility as it can travel with an axle load of 10 tonnes, 12 tonnes and 16 tonnes. It features a 60-metre telescopic boom, a whole 10 metres more than its predecessor, the LTM 1090-4.1. The new crane carries 8.8 tonnes of ballast with a 12-tonne axle load, 2.1 tonnes more than its predecessor. In this configuration the LTM 1090-4.2 is now the most powerful 4-axle crane on the market. ECOdrive and ECOmode make the new 90-tonne  crane particularly green with lower fuel consumption and noise emissions. Liebherr innovations VarioBallast and VarioBase® also deliver improved performance, flexibility and safety for this new crane model.

Efficient global mobility

The development of the new LTM 1090-4.2 focused on meeting a very wide range of axle load requirements to enable the crane to deliver low cost global mobility. Even in countries where mobile cranes with a 12-tonne axle load are permitted on the roads, crane operators have for some time been demanding cranes which can be driven with 10 tonnes per axle by simply removing the ballast. This version delivers major benefits for road licensing and route approval procedures.

Despite having a boom which is 10 metres longer than its predecessor and whose weight particularly weighs down the front axles, Liebherr engineers have managed to create uniform axle loads of less than 10 tonnes for the new LTM 1090-4.2 and not to exceed a gross weight of 40 tonnes. To achieve this, the first axle was positioned in front of the front sliding beam box and the spacing between axles 2 and 3 has been extended. The larger axle spacing also has a beneficial effect on road licences in many countries.

This also creates more space in the ballast storage area on the undercarriage which allows the ballast radius to be adjusted over a very large range. The new LTM 1090-4.2 also features the innovative VarioBallast which means that it can be operated with two different ballast radii: 3.77 metres or 4.71 metres. The ballast radius can be reduced by 940 mm quickly and easily using standard mechanically slewing ballasting cylinders to ensure that the ballast radius remains inside the supports. This solution is one of the main benefits of the new 90-tonne model when used in constricted conditions.

The maximum of 22.5 tonnes of ballast is distributed so variably that in addition to the 10-tonne and 12-tonne axle load versions, uniform axle loads of 16 tonnes can also be achieved, for example for Great Britain.

The greater space between axles 2 and 3 is used to store support timber. This eliminates the need for a box for support timber at the rear of the vehicle. In addition, the new 90-tonne crane has additional storage compartments for attachment and other equipment on the crane chassis.  

Even with 16.00 R25 tyres, the new crane measures just 2.55 metres in width. The vehicle width has been reduced by 0.25 m, which is not just a benefit when driving on public roads, but also makes a real difference on constricted building sites.

Great performance with 60-metre telescopic boom

The ability to carry up to 8.8 tonnes of counterweights with an axle weight of 12 tonnes is an outstanding value for a 4-axle crane. In combination with VarioBallast, Liebherr has managed to make the new LTM 1090-4.2 the most powerful crane in the 12-tonne axle load configuration. This means that crane operators can complete the vast majority of crane jobs at low cost without having to transport additional ballast. Furthermore, the optional VarioBase® generates a significant gain in lifting capacity in working areas above the supports. For the very first time, the combination of VarioBallast and VarioBase® provides crane operators with maximum flexibility for difficult sites in the 4-axle class.

Its length of 60 metres makes the telescopic boom one of the longest in the entire 4-axle class. In addition a 9.5 to 16-metre folding jib is available which, as an option, can also be adjusted hydraulically between 0° and 40°. A 2-metre assembly jib and a rooster sheave, which can be swung to the side, round off the equipment list.

ECOdrive and ECOmode reduce fuel consumption and noise emissions

A six-cylinder Liebherr diesel engine in the undercarriage which develops 330 kW / 449 bhp and torque of 2,335 Nm provides the LTM 1090-4.2 with all the power it needs. The engine meets the Stage IV / Tier 4f emissions regulations. Liebherr can also supply the engine in an ECE-R.96 version (which corresponds to Stage IIIa) for countries with less stringent emission regulations.

The new ZF-TraXon gearbox is used to transmit the power to the crane's axles. As with its predecessor, the AS-Tronic, the 12 gears are changed automatically. ECOdrive is a new feature. The add-on eco mode defines enhanced drive properties which save fuel and reduce noise.

Liebherr has continued its single-engine strategy on the new LTM 1090-4.2. The omitted weight created by the elimination of the superstructure engine from the predecessor model has been used to deliver a longer boom and more ballast with an axle load of 12 tonnes.

In keeping with the latest developments from the Liebherr mobile crane series, the new LTM 1090-4.2 also features ECOmode for crane operations to reduce fuel consumption and noise emissions.  On the one hand, the complete pump drive can be disconnected automatically when the engine is idling and then reconnected by the intelligent controller in a matter of seconds when it is required. On the other, the crane controller calculates the perfect engine speed for the working speed selected using the control lever to avoid unnecessarily high engine speeds. This results in fuel consumption being reduced by up to 10% during crane operations.