Chains are an indispensable component in many hoisting technology applications. Of course, safety and compliance with the pertinent standards are just as vital here, as they are with other hoisting gear. This is because, whenever heavy loads are moved, there can be an associated danger for the people who are in the immediate vicinity. Quality assurance is therefore particularly important in the production of the chains for hoisting gear. The company Ketten Wälder puts its trust in measurement technology from HBM in its production systems.
Hoisting technology is one of the applications for the chains produced by the company Ketten Wälder GmbH, from the Upper Bavarian town of Bad Endorf. The mid-sized company employs 40 people, and produces up to 4,000 meters of high-quality chains every day. The processing of the base materials, such as steel for the chains, is a complex process, and all the sequences have to be accurately coordinated.
Different grades and dimensions of the raw materials are first lifted onto a coiler. A drawing machine then draws the material to the required diameter. After that, the individual links of the chain are produced in the chain bending machine, where link by link, they are neatly bent, and lined up and mounted, end-to-end. The next production station has modern welding machines, to weld the individual links. The welding process in the machines is fully automatic.
Important parameters such as upset pressure and current flow are measured at the same time, to gage the quality of the weld seam. In the next, fully automatic stage, important information such as the quality class, a traceability code and the manufacturer’s mark, is stamped into the material. The chains are then hardened and tempered. To do this, they are first heated, and then pass through a bath in which they are quenched – that is, cooled very quickly. They are then re-heated until the required strength and elasticity are ensured.