BAUER BG 39 in use for environmentally friendly heat supply project in Switzerland

Located on the eastern outskirts of Zurich, the Lengg area is an important location for various healthcare and research facilities, a popular local recreation area and the site of one of Zurich's two lake waterworks. Due to its density of hospitals and clinics, the area is to be developed as a "health cluster" of European importance. One part of the project is the planned environmentally friendly heating and cooling supply with lake water and a network of heat pumps for the hospitals and research institutes. Energie 360° AG was commissioned with the contracting of the heating network for this purpose.

Lake water is to be extracted from Lake Zurich using underground lake pipes under the Wässerig meadow in the municipality of Zollikon. A central lake water station with a heat exchanger will be built underneath, from which pipes will lead to a transfer station, also underground. 

KIBAG Bauleistungen AG was commissioned by Energie 360° AG Zürich to excavate the excavation pit closures for a circular shaft with a diameter of 19 m and a final excavation depth of around 22 m on the Wässerig Area for the construction of the lake water center. The company decided to create the excavation using overlapping bored piles, for which the company's own BAUER BG 39 was used. 

The piles with a diameter of 1,500 mm have a length of 26 m and bind around 4 m into the molasse rock. Drilling accuracy played a key role in the production of the bored piles. This is because the smaller the deviation from the drilling axis, the smaller the overcut of the piles can be set. As a result of optimizations by KIBAG in the form of an elaborate drilling template, the use of HD drill pipes and the measurement of each borehole using a special measuring probe, a drilling accuracy of +/- 0.5% on average to the vertical could be achieved and tested. This enabled the client to save more than 20% of the piles while maintaining the same shaft size. We congratulate KIBAG AG on this achievement and are proud to be part of the success story with our machine.