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Flexibility is what you need
Liebherr duty cycle crawler cranes can be used for a wide range of applications. As an optimal basic machine for deep foundation work, the crawler cranes can be equipped with slurry wall grabs or hydromills. With fixed and swinging leader, they are ideal for use as piling rigs. They become a drilling rig when fitted with pile grab and casing oscillator. With attached vibro-flot or tamper weights they are used for soil compaction.
Thanks to their robust design and the high line pull of the main winches, the HS series is perfectly suited for slurry wall installations. Any type of grab, either mechanical or hydraulic, can be fitted.
The modular design of the slurry wall grab HSG 5-18 promises a high level of flexibility and enables the optimum adaptation to jobsite requirements.
The vertical measuring system is fully integrated in the Liebherr control system. Vertical correction is possible. This allows for a high level of accuracy, even at great depths.
The vertical assistant measures the deviations between the slurry wall and the grab along the x- and y-axes, as well as the rotation round the z-axis. An innovative graphically displayed host system guides the driver through the whole process.
The data is clearly displayed on the monitor in the operator's cabin. The process data can be exported and analysed.
Slurry walls can be installed practically vibration-free using a special cutter (hydromill). Cutter wheels are mounted on the bottom of a steel profile frame and continuously break up and crush the soil at the bottom of the trench.
An important advantage of the hydromill is that it can be deployed for almost all types of soil, including rock. Furthermore, work can be carried out at depths of over 100 m.
After land reclamation the loose soil is compacted step by step using a vibro-flot. Through the vibration the soil grains change from their initial loose layering to a denser layering. This improves the subsoil of the building site.
SAOS is installing 6,300 m² of slurry walls for the metro extension using a Liebherr HS 8100 with the corresponding Liebherr slurry wall grab, type HSG 5.
SAOS is excavating bites of 2,800 × 1,200 mm with depths of up to 54 m. At 130 m² per day, the Liebherr package underlines its high productivity.
In order to improve the soil conditions, the Finnish company Takanen is applying the Liebherr duty cycle crawler crane HS 8130 with a 14-tonne dropweight. The weight was dropped from a height of 10 m in free fall onto the building area to be compacted.
Achieving an impact between 50 and 70 kN/ m², the ground was compacted down to a depth of 7 m. The weight hit the ground 110 times per hour, about 50,000 times during the whole project phase.
The piling elements are installed dynamically. A hydraulic hammer, usually mounted on a piling rig with leader, impacts on the piling element with the aid of a ram mass. Impact driving is used for the same purpose as vibrating, whereby the hydraulic hammers currently available are able to transfer much higher forces.
Duty cycle crawler cranes are equipped with universal bored pile grabs when installing pile foundations with casing oscillators. These can be deployed for different soil conditions. The universal pile grabs are extremely robust and fitted with hard-wearing components.
A further advantage is that the body of the grab has a streamlined design so that a high falling speed can be achieved in water.
The modern concept of the new leader impresses with easy and quick assembly by means of pin connections. A high degree of stability is ensured through the lattice boom design. The proven duty cycle crawler crane HS 8200 can be used as a carrier machine.
The LRH 600 piling rig is particularly suitable for heavy piling operations with large radius.
For the installation of casings, the duty cycle crawler cranes are always fitted with a casing oscillator. These are coupled with the carrier machine and excel through their extremely robust design. They are driven through the carrier machine’s hydraulic system.
Through alternate rotation to the right and to the left the casings are finally pulled upwards or pressed downwards.
A heavy tamper weight is dropped from heights of up to 40 m onto the ground to be compacted. This dynamic input of energy increases the density. Liebherr duty cycle crawler cranes carry out the compaction process efficiently and automatically with free-fall winches and crane control.