125 holes - 400 mm wide and 170 cm deep
A Husqvarna drill bit tall as a man!
It is for a new office building being constructed on Lindholmen in Gothenburg.
“The conditions out here are a little special. The concrete foundations are most likely from the shipbuilding era. We had to drill through the entire old foundation to drive piles for a new one,”
says Jimmy Johansson, a foreman from Göteborgs Rivteam.
A total of 125 holes have been drilled. Half of these were 170 centimetres deep, and the others were about 1 metre deep. All holes were 400 millimetres in diameter.
Demands on both equipment and technology
Deep, large diameter holes place demands on both equipment and drilling technology.
“A drill core weighing up to 400 kg is hard to handle, especially if you run into problems and the drill gets stuck down there,” says Kent Eriksson at Husqvarna.
Göteborgs Rivteam acquired two Husqvarna DM 406 H hydraulic drill motors and DS 70 AT drill stands to perform the job. The drill stands were ordered specially and extended to handle long drill bits. Husqvarna Diagrip D 1200 drill bits were used for the job. The drilling has taken just over a month.
“We have drilled some two and a half holes a day, and I think this is quite satisfactory,”
says Jimmy Johansson.
Hydraulic wall sawing as complement
In addition to the drilling equipment, Göteborgs Rivteam also used the Husqvarna WS 355 hydraulic wall saw with 1,600 mm blades, also from Husqvarna, to cut out the two large ventilation shafts that were built under the new foundations.
“We have sawn nearly 100 metres in length, and the work has been done without any major hiccups. Kent Eriksson from Husqvarna is great to work with. He is always there whenever help is needed.”
The construction of the new office premises is underway right beside the river Göta älv, which also has an impact on how work is carried out.
Göteborgs Rivteam has pumps on site to suck up water that leaks in from the river. The turnkey contractor for the construction work is AF Bygg, who have been contracted by Eklanda Fastighets AB.