The Bürkle Company, located in the western Baden-Württemberg city of Sasbach, is an owner-operated precast concrete manufacturer, well established on the market for more than 60 years. In addition to the precast plant, the company is a very successful manufacturer of precast basements. In 2017, the magazine Focus-Money nominated Bürkle once again as the fairest supplier of precast basements in all Germany. More than 500 polled customers placed Bürkle at the top of five leading German manufacturers of precast basements.
Over recent decades, Johannes Bürkle, who leads the company in the second generation, has successfully and continuously further developed the company with innovative ideas – in production, new products and marketing – to ensure that achievements such as those described above are not left to chance. The Bürkle Company invested in a circulation system for precast slabs, double walls and solid walls as early as 1992. This pace-setting investment was continued again and again, improved or supplemented by new production technologies. All these measures led to continuously increasing plant output, which now amounts to around 100 pallets per day. Apart from this enormous initiative, it was always important to Johannes Bürkle never to lose sight of the company’s productivity and the working conditions of his highly motivated team. This is why, in 2017, following a very thorough pre-planning phase, he decided to replace both the shuttering robot station and the pallet turning station, including compaction. At the same time, the production floor was extended by adding an annex, and all pallets were scheduled for renovation. For implementation, he decided on the plant engineering company Weckenmann and the automation specialist SAA, who together with him developed solution proposals that finally proved to be optimal in the selection process.
Pallet turning station
The performance of the turning system, in operation from 1992, no longer met current requirements. It required operators manually to move the heavy tensioning blades needed for fixing the wall elements in place during turning. The tensioning height was unchangeable, and turning of the insulated walls was therefore extremely difficult. The required wall thickness was achieved only by mounting the spacer bolts manually.
The turning system supplied by Weckenmann, which was placed in the new extension of the hall, completely eliminated these restrictive shortcomings: "The tensioning blades remain in the turning frame and do not require removal. They are now pushed in and pulled out horizontally." The tensioning level is adjusted by an electric motor: i.e., the tensioning blades rest either on the concrete shell, or on the insulation for walls with thermal insulation.
"The turning device automatically adjusts the required wall thickness based on CAD data. This eliminates manual adjustment of the otherwise customary spacer feet." The vibration station, also supplied by Weckenmann, guarantees optimal concrete compaction at a very low noise level. The compaction movement of the two pallets can be selected to take place in circular or linear directions, in x or y axis directions.
Shuttering robot station
According to the manufacturer, the performance and the small footprint of the solution implemented by the Bürkle Company are unique. The challenge here was to accommodate a high- performance plant in a very confined space. The performance specification had called for a pallet with an average of 13 forms, which can be both raised and again set down – and processed within a cycle time of 10 min., including pallet change.
The following work steps can now be performed on only one pallet station:
Scanning of a pallet size 3 x 10 m to determine where form profiles are located.
Lifting of the forms by robot, followed by transport, cleaning and storage.
The forms are cleaned and oiled and are subsequently either stored or moved on by a magazine storage unit.
Cleaning of the pallet by a traveling cleaner.
The robot oils specific areas of the pallets: i.e., where the forms are placed.
Precise positioning of the forms and activation of the magnets.
Experts from Bürkle, Weckenmann and SAA rose to this challenge with great determination. The acceleration and speed characteristics of robots, form transport, magazining units and cleaners were markedly increased, and the movement algorithms of the robots and the magazining units optimized from the previous plant. Even the smallest improvement potential was utilized wherever possible. The specifications were met, and the plant now makes a very dynamic impression.
Reworking the pallets
Reworking the pallets, up to 25 years old, was an important step for maintaining high quality levels. Weckenmann has specialized here, since it has the necessary prerequisites in-house. Knowhow in formwork construction is crucial here and for effective machine engineering and utilizing the available shop-floor space. The results of meeting this logistic challenge are pallets, which, in terms of the quality of the contact areas, do not have to fear comparison with new pallets. The difference between the old and new pallets is more than apparent on the precast elements.
Robot for embedded parts and empty pallet storage
The shuttering robot previously in operation will be converted in the course of the year to a robot for embedded parts, which will install power outlet boxes, threaded sleeves and other components on the pallet in accordance with CAD data. An integrated glue gun first applies the hot glue required for fixing with spot-on accuracy. This investment is also based on a joint effort by Bürkle, Weckenmann and SAA.
It is also worth mentioning that Weckenmann had already installed a pallet storage unit in 2017 that can buffer up to 10 empty pallets between the demolding station and the shuttering robot system. This investment increased the output of the plant by equalizing the existing differences in cycle times of the two processing steps of demolding and shuttering.
With this investment step, the Bürkle Company once again remains true to its chosen course of continuity. This is a clear commitment to the production location and the importance accorded to its own staff: the unrelenting search for improvement possibilities and the recognition that companies can sustainably succeed only when continuous and constructive investments are made. Living off accumulated achievement is not an option for Johannes Bürkle, as emphasized by his own statements.