WIRE NEWS WN March 2019 | Page 8

From the Wire Coil Straight to 300-mm-Long Full-Thread Screws of 10-mm-Diameter – all in One Machine Cold forming achieves record-breaking throughput A new all-in-one machine from Amba produces full-thread screws of 300 mm length and an outside diameter of 10 mm directly from the coiled wire. While in the screwmaking industry, typically 30 to 40 threads are rolled per minute – this does not include the forming of the screw head – , the new machine achieves a rate of more 100 screws per minute – including the screw head! The machine designed for the production of full- thread screws used in structural timber design is almost ready to be shipped to a customer in Germany. It is the world’s first machine to produce screws of this length and diameter from the coiled wire to the finished product in just one continuous cycle. The machine works according to the Amba-developed all-in-one principle, i.e. all process steps from paying off, cutting-to-length and straightening the wire, forming the head to thread rolling are performed by one machine. The new all-in-one machine produces more than 100 up to 300-mm-long screws per minute in one continuous cycle. Currently, Amba achieves a production rate of more than 100 screws per minute, i.e. three times more than common machines on the market, which only roll the plain threads. The recipe: Cold forming instead of machining The new machine is exemplary of a current trend: In the manufacture of long metal components with varying cross-sections along their length, cold forming has been taken over from machining. Manfred Houben, one of the three Managing Directors of Amba, explains this trend: “Cold forming processes achieve much higher throughput rates than 8 WIRE NEWS March 2019 Manfred Houben (left) and Lars Henning, both Managing Directors at Amba, are inspecting one of the 300-mm-long screws. machining operations because the items do not have to be individually fed, clamped, machined and ejected. In this way, discontinuous manufacturing becomes a quasi-continuous process. In certain applications this may result in a productivity improvement of one order of magnitude.“ The all-in-one principle is