Having been active in the building industry for almost a whole century, Gebr. Kaltenbach GmbH & Co. based in the Swabian town of Dornstetten opted for an extensive modernization of its carrousel system. The goal was to improve both product quality and competitiveness through the use of a new technology. Over the past two years, the entire reinforcement production was therefore upgraded to the current state of the art and a new shuttering and deshuttering robot installed. Progress Maschinen & Automation, a member of the Progress Group, was commissioned with supplying and installing the plant. Kaltenbach is highly satisfied with the result.
Gebr. Kaltenbach GmbH & Co. – based in Dornstetten in the northern part of the Black Forest – calls itself a “Swabian veteran” of the building industry. Founded in 1923, the family business quickly expanded its activities from the mining of raw materials to their processing and refinement. Today, Kaltenbach is active in the mining of crushed stone and gravel as well as in the production of asphalt and ready-mixed concrete. Since the 1980s, the company has also been producing precast concrete elements using its own raw materials.
Kaltenbach initially limited its operations to manufacturing hollow-core slabs and precast floor slabs in line production. With the installation of a carrousel system in 1993, the company increasingly focused on the production of precast floor slabs. In addition, double walls, staircases and balconies are still being manufactured to this day.
Kaltenbach is convinced of the benefits offered by the precast concrete elements: “These are products which lead to significant reductions in construction time and cost savings on the construction site,” says Werner Wößner, the company’s Division Manager for precast concrete elements. The market is, however, extremely competitive. “That is why it is particularly important to be able to deliver excellent quality in a reliable and efficient way,” Wößner continues.
The goals of improving quality and increasing efficiency sparked off the modernization measures successfully implemented by Kaltenbach over the last years. Two years ago, the Swabian company invested in a new steel processing plant. In addition, a fully automated shuttering and deshuttering robot was just recently put into operation. Progress Maschinen & Automation, a subsidiary company of the Progress Group, was the partner in both projects.
During the first step of the modernization implemented in 2015, the straightening machine for the supply of line wires was replaced, a new plant for lattice girder processing installed, and the controller of the reinforcement robot and cross-wire machine exchanged.
The newly installed straightening machine of type MSR 2BK enables Kaltenbach to straighten, cut and bend reinforcing steel from the coil with a diameter of up to 14 mm. The steel is straightened to precision thanks to the multi-rotor straightening technology – an important prerequisite for high-quality precast concrete elements. The plant has nohydraulic drives or components, and the straightening nozzles do not require maintenance thanks to the absence of bearings. All of this simplifies both everyday operation and maintenance requirements. In addition to that, the plant allows doubling of the previous coil weight: the use of 5-ton coils enabled the time needed for coil change to be reduced, which resulted in a significant increase in productivity.
As an additional measure, processing of the lattice girders was fully automated: in the process, a separation and handling beam removes the requested lattice girder from the active magazine and transports it to the next lower level where it is cut to the specified length by means of a cut-to-length machine of type GTA. In case the next lattice girder is too short, it can be welded together with any remaining parts in an automated process, thus eliminating any offcuts. The completed lattice girders are then stored in an intermediate buffer magazine from where they are retrieved for insertion into the pallet.
“We are highly satisfied with the result,” Wolfgang Hess, Plant Manager at Kaltenbach, sums up. Wößner states more precisely that everything went exceptionally well – from sales all the way to installation. The Division Manager adds: “This was what prompted us to place the follow-up order for installation of a shuttering and deshuttering robot with Progress Maschinen & Automation.”
The plant called Form Master was put into service some weeks ago. At Kaltenbach, two robots perform all steps of the shuttering process in a fully automated operation. At the start of the production cycle, a warehouse robot retrieves the shutters from their storage locations and passes them to the shuttering robot. The shuttering robot positions the shutters on the pallet in accordance with CAD specifications prior to activating the magnets. The robot is additionally capable of placing magnets for embedded parts. At the end of the production process, the pallet is scanned, the shutters are unlocked, removed and fed into the cleaning system. The cycle is completed with the warehouse robot returning the shutters to their storage locations.
The shuttering process also uses Infinity Line, a patented system that ensures optimum combination of the shutter lengths. The system enables gapless shuttering without the use of filler elements. This results not only in significant cost savings but also in an improvement of the quality of the precast concrete elements: being able to omit the filler elements ensures perfect visible edges.
Wößner and Hess have come to a positive conclusion after just a few months. The company was able to not only realize shorter cycle times but to also improve the quality of the elements produced. “Especially the Infinity Line system is an excellent tool. I wouldn’t have believed that this system worked so well,” Wößner goes on to say. In addition, the robot was making work much easier for the employees. The Division Manager gives praise to one specific hallmark: “The Form Master enables us to place magnets not only for standard electrical sockets but also for low-voltage and LED lamps.”
For Wößner, the investment has been worthwhile. “Both in reinforcement production and in shuttering and deshuttering, everything has been running smoothly right from the start.” Managing Partner Armin Kaltenbach also believes that the company is fully geared up for the future. “It is our philosophy to be a fair and reliable partner to our customers. With the modernized plant, we will now be able to fully meet this claim.”