Liebherr LG 1750

The Liebherr LG 1750 is a highly versatile 750-ton lattice boom truck crane designed for large-scale lifting tasks. With a maximum load moment of 9,864 t·m (in the SDB2 system), this crane is well-suited for applications like wind turbine assembly, bridge construction, and other demanding infrastructure projects. Its maximum lifting capacity is 750 tons at an 8-meter radius, making it capable of handling extremely heavy loads with precision.

The LG 1750 is built on a robust, torsion-resistant, self-manufactured crane carrier frame, with an 8-cylinder Liebherr diesel engine that delivers 505 kW (686 hp) and a maximum torque of 3,000 Nm. This engine meets the latest emissions standards (97/68/EG and EPA/CARB) and is paired with a ZF TC-TRONIC automatic transmission featuring 12 forward and 2 reverse gears. The crane’s drive system includes 9 axles, all of which are steered to ensure excellent maneuverability on site. The first six axles are driven, with steering controlled hydraulically and electronically to adjust to various road speeds and displacement scenarios.

The suspension system is fully hydropneumatic with automatic leveling, allowing for axle pressure equalization between the paired axles. Axles 7 and 8 feature active steering up to 60 km/h, aiding the crane’s mobility on-site or during transport. The crane’s braking system includes all-wheel servo-air brakes with optional retarders for enhanced safety during operations.

The crane’s superstructure features Liebherr’s modular slewing platform design, which includes a planetary slewing gear powered by an axial piston hydraulic motor, allowing for smooth, controlled crane movements. The slewing speed is finely adjustable and provides precise control during lifting operations.

The boom system includes:

• Main Boom (S System): Extends up to 140 meters with the SDB configuration and derrick system, allowing for heavy-duty lifting operations.
• Lattice-Type Luffing Jib (W System): With lengths between 28 to 105 meters, the W-jib is used for tasks requiring additional reach.
• Fixed Lattice Jib (F System): Extends between 12 to 21 meters with angles of 10°, 15°, or 30°, suitable for lighter loads and wind turbine installation.
• Derrick Boom: With a boom length between 91 and 140 meters, supported by a counterweight frame of 400 tons, this configuration offers maximum lifting stability and capacity.

The LG 1750 features a comfortable cabin designed for long shifts, with advanced controls and monitoring systems, including cameras, a touchscreen display, and a climate-controlled environment for the operator. Safety features include hoist limit switches, wind-speed indicators, and an aircraft warning control system, ensuring safe operations even in challenging conditions.

For site transport, the crane’s wide swing-out outriggers and large support base provide excellent stability, while the 60-ton boom nose and auxiliary hydraulic systems ensure adaptability across different lifting tasks. Counterweights can be easily configured up to 400 tons, further enhancing the crane’s lifting power.

The Liebherr LG 1750 offers the best of both worlds: the lifting power of a lattice boom crane with the mobility of a truck-mounted carrier. This makes it ideal for projects requiring high capacity and rapid deployment, such as wind farm construction or infrastructure development. Its advanced hydraulic systems, efficient transportability, and modular design ensure that it remains one of the most capable cranes in its class.

New SL12D2FB Boom System

The new boom system enables the LG1750 to erect new large types of wind power systems at tower heights from 140 to 150 metres. The design was derived from the former successful SL9D2FB boom, the main boom arrangement with fixed jib and derrick system. One of the changes was the use of three stronger 12 metres lattice boom with a width of 3.5 metres instead of 3.0 metres in the lower section of the main boom, and by lengthening of the fixed jib, the new SL12 system increases the load capacity and height under the hook. The LG1750 can achieve a greater load capacity of 141 tonnes at a height under hook of 143 metres and 97 tonnes at 160 metres.

Milestones

• First LG1750 in USA, Kansas-based Trand Inc. (Dec 2019)