On 24 October, the time had finally come and students of materials engineering at the Nuremberg University of Applied Sciences Georg Simon Ohm were able to visit the Walther Dachziegel GmbH roof tile factory in Langenzenn. The excursion took place as part of the third course in the subject “Heavy Ceramics” by Prof. Dr. Barbara Hintz, in order to give students of the third semester “Materials Engineering” an understanding of the extraction of raw materials and the production of (roof) tiles.
In the clay pit and in the rain
After being welcomed by the head of the laboratory and former graduate of the Nuremberg University of Applied Sciences Catrin Müller, the first station led to the extraction of raw materials as the first important step in the production of (roof) tiles. Here, Ms Müller explained the special features of the clay pit in Langenzenn and how, for example, sand is used to regulate the shrinkage of the roof tile blank. Along the way, the students’ questions, e.g. how long the clay reserves in Langenzenn will last for roof tile production, were answered.
In the meantime, the weather had deteriorated noticeably and the tour of the clay pit took place while lightning flashed and the excursion participants listened to Ms Müller’s words on clay mining in various layers of the clay pit in the heavy rain.
Fortunately, the excursion could then be continued in the dry with a detailed guided tour through the individual processing stations. The students vividly experienced for themselves how solid, large lumps of clay are turned into a homogeneous and plastic mass for brick production. The students were particularly impressed by the heavy rollers in the pan grinder, which they could admire at close range.
Plain tiles and after-work bricks
The students then followed the path of the typical plain tile from the press, which gives shape to the wet blank, through the dryer and the ceramic firing.
In the process, they learned what “Feierabend” (after-work hours) tiles are and what quality features, such as frost resistance, finished roof tiles must possess. It became clear how a very high-quality heavy clay product is created from a natural raw material in various finishing steps.
Afterwards, the students could choose their personal favourite among the various traditional to modern roof tile designs. The majority opted for the traditional plain tile with royal blue glaze.
Quality assurance as a field of work
The final part was the quality assurance laboratory, where Mrs Müller explained the various quality assurance steps and test procedures. For the students, this not only opened up a possible field of work for materials technology graduates, but also why their training is necessary.
After a final visit to the exhibition area where, for example, solar roof tiles are on display, the impressive excursion ended with the bus ride back to Nuremberg.
We would like to thank the Walther Dachziegel GmbH roof tile factory in Langenzenn, Bernd Zimmermann and especially Ms Catrin Müller for making this instructive factory tour possible and for conducting it. Special thanks are also due to the Graduates’ and Sponsors’ Association, as the financial support with the assumption of the bus costs made it possible for everyone to participate free of charge and enjoy the trip.