Duration: 25.11.19 – 29.11.19
Product: This company is producing semi-finished products for industries in the gear-, engine-, turbine- and press constructions sector. Their worldwide clients are for example oil and ship building industries. Their forged products are produced by steam hammers and presses operated by highly skilled workers.
By-product: A wide variety of by-products are generated during the production of their semi-finished products. When the workers of Hammerwerk Erft forge a punched disc for example, they use a mandrel to drive a so-called Stopfen out of the middle of the disc. Depending on the dimensions of the produced punched disc, this Stopfen can weight up to 300kg. The by-product is sold per kilogram, but its form is lost.
Inspiration: Since the first day of my studies at KISD, one of these Stopfen was laying on the window sill of the metal workshop. I always wondered how this soft looking piece of solid steel was formed. Due to a forging project at KISD in 2016, I participated in a factory tour at Hammerwerk Erft. This tour then provided an answer to the long-standing mystery of how the Stopfen is made.
Organisation: The person who was leading the factory tour was Andreas Ecke. As I was able to re-establish contact with him, I mentioned the Stopfen and expressed my interest in getting hands-on with this industrial by-product. They were on board and also assigned their current apprentice to me.
Potentials: This by-product is a constant result of the ongoing production of punched discs, the occurrence is therefore reliable. The form is always round and is varying in scale and weight. The combination of high-end forging equipment and skilled and motivated workers enables to forge almost anything in any size.
Challenges: This environment was not just filled with overwhelming possibilities, but also with life-threatening moments. One has to be alert at any time, not to stand in the way of tonnes of blazing hot material.
Goals: I want to find the most logic, easy and efficient way to manipulate this by-product. Considering the usual production of punched discs, it became clear to simply produce bowls in a very similar but slightly different manner. Instead of driving the mandrel completely through the material, its function is to merely dent into the glowing hot Stopfen. In this way, the steel would squish, forming a unique bowl.
Production: Regarding the omnipresent dangers of the working environment, it was necessary to become familiar with the facilities, behavioural code, tools and material was crucial. We collected the Stopfen in various sizes and I choose the appropriate mandrels. The preparations ended with putting the by- products into the oven. After 15 min, they reached around 1200°C and were ready to be forged. Depending on the weight, the white glowing Stopfen were either dragged out of the oven and thrown on the forging saddle by tongs or grabbed and placed by an auto manipulator. The last step before the actual forging process, was positioning the mandrel in the middle of the glowing piece of steel. With a weight of approximately 1000 tonnes, the forge press forces the mandrel into the by- product. Depending on the number of pushes, the bottom of the bowl gets thinner and the sides get bigger. Thanks to efficient execution and planning, there was still time left to experiment at the end of the week. The results were two additional side tables. With a wire brush disc on an angle grinder, the layer of slag is removed and a layer of wax polish is applied.
Reflexion: Designing products from by-products in such a hazardous environment was a very valuable experience. Being confronted with danger at any given moment, lifting heavy weights with tongs, sweating in front of pieces of steal that are 1200°C hot and pressing with the maximum force of 1000 tonnes during the process, made me feel humbleness. The language of the process marks on the finished pieces was definitely worth the effort. Considering this daily hard and dangerous work that the blacksmiths at Hammerwerk Erft are doing, I would like to express my highest respect. Within just a few days I already felt my muscle ache. My production phase took place during the morning breaks of the actual production, to prevent from interrupting the daily schedule. Every step of the production needs to be well thought through. During the production, the communication between the operating parties is limited due to the hammering noises. Everything is coordinated via signs language and shouts. Despite these extreme circumstances, there was still room for improvisation and experimentation. Even though the production used an ever-same by-product and followed therefore a more or less strict plan, there was always the need to adjust, level or reheat the glowing steel.
Prospect: In the course of collecting suitable Stopfen for the production, I noticed another type of by-products. Before the raw forging material, the cast iron bars from East Europe are cut in length to be put into the oven, the ends of the bars are cut off with a band saw. These by-products are either square or round and have at least one plane surface. I made one bowl and the side table legs from this kind of formed offcut. Next time I would be at Hammerwerk Erft, I would not change a single thing of the work process, because it worked out perfectly. The offcut by-product though could be worth of a further exploration.