Franken-Schotter has made significant improvements in the production process for building blocks for walls and embankments at its site at Dietfurt, Germany.
The company says that its new excavator-mounted milling attachment from KEMROC removes a troublesome layer of marl while profiling the uneven surface of its limestone building blocks in a matter of minutes.
The manufacturing company employs 360 people, and has three production plants located in the districts of Weissenburg-Gunzenhausen, Eichstaett and Roth producing asphalt mix, gravel and dimensional stone.
The company says it is a market leader in Germany for dimensional stone and its product is sold worldwide.
At the Dietfurt quarry the rock has a compressive strength of between 60 and 70 MPa, and the formation consists of several layers. Depending on the thickness of the layer, rock is extracted as blocks using either drill-and-split or cutter saws.
When possible, the ideal size of a block is 3m x 1.9m and all blocks are broken out of the quarry wall using a wheeled loader.
Some layers of rock are covered by a 3-7cm deposit of marl, and previously such blocks had to be left for up to one year until the troublesome marl layer broke loose.
Occasionally, the rock layers have surfaces so uneven that they cannot be used for gardens or landscaping, resulting in product with a much lower value.
After a full week’s testing on low-value blocks, it was decided in June 2017 to purchase a KEMROC attachment for use on the company’s excavator. The most suitable attachment for this application proved to be the ES (Flexator) range of grinders, and the ES 60 HD, with 60cm wide drums fitted with carbide tipped picks, was selected.
With the KEMROC cutter mounted on its excavator, it took about one minute to remove completely the deposit of marl and profile the surface of each block of limestone, says the company.
“After a short period of time our excavator operator got a good feel for the KEMROC attachment. With this grinder, we have made a dramatic improvement to the value of our product in a very rational way,” says Sven Kersten, assistant quarry manager at Franken-Schotter.
“We have also eliminated the spalling of our blocks in winter and we are confident they can be used without hesitation in any wall.”
