With our new BM12 screw-making machine, we have further expanded the range of our All-in-One machines. The new machine can process up to 18-mm-diameter wire. This makes it the most powerful of all our machines.

Forming forces about 40 percent greater than those achieved with the predecessor model BM 10 are needed to be able to process wire of such large diameters. While wire of up to 12 mm diameter continues to be cold-worked also in the new machine, thicker wire – up to 18 mm – is now processed at elevated temperatures. This is a novelty, even for our engineers with long-standing experience. The machine is designed for production rates between 50 and 70 items per minute.

To be able to handle the new wire sizes, we have implemented numerous innovative design features. The thicker wire and the heavier screws call for special engineering solutions to ensure safe downcoiling of the wire and smooth transport of the workpieces through the machine. A novelty is that the large-diameter screws are now hot worked: Before the upsetting process, they are inductively heated inside the machine. In terms of design this means that the forming tools have to be cooled and certain other components must be shielded from the resulting intensive heat radiation. Additionally, the temperature of every heated workpiece is checked by inline measurements. Items below the specified minimum temperature are automatically removed.

To ensure that the machine is able to provide the performance required, comprehensive numerical simulations of the forming behavior were performed and subsequently verified in real tests. Moreover, the new machine features a number of advanced technologies, such as the compact press drive unit and the overload coupling in the main drive, that we have already successfully implemented in other machine models.

The first order is in the pipeline

The first machine of the new series has been ordered by a US customer who will use it to produce up to 600-mm-long screws with diameters of up to 18 mm directly from the coil. The new BM 12 will replace two existing machines arranged in series that require manual reloading between the two. Here, the All-in-One principle will provide a marked boost in efficiency as it combines all process steps from downcoiling, straightening and cutting via upsetting of the screw head up to thread rolling within one single machine.