The manufacturing method patented by the Weisser & Söhne Werkzeugmaschinenfabrik in combination with the MAPAL tool technology with HSK-T interface offers the user the greatest possible benefits. High-precision inserts with a large working length, stable mounting of the inserts in a compact body and the optimum PcBN cutting material are the characteristic elements of the MAPAL turning tools.
The key factor here is the large length of the insert. Combined with the contact angle, it gives the MAPAL tools a possible effective machining length of up to 45 mm, with which surface roughnesses of < Rz 2 and radial run-out accuracies of 3 µm are achieved. The product range offers VDI and HSK-T connections in versions as single-carrier with one insert or as double-carrier with two inserts. Depending on the machining allowance, tools with one insert rough and finish-machine the workpiece in one machining step or in two machining steps with different stock removal rates. With double-carrier tools, one insert is used for the pre-machining and an identical insert for the finishing operation. That boosts the process reliability and increases the tool life. The MAPAL tools can be installed vertically or horizontally, depending on the workpiece.
For example, a gear wheel hardened to 58-60 HRc with a root length to be machined of 25 mm is machined using the MAPAL tool technology. A horizontally mounted single carrier with HSK-T connection is used. The total machining allowance of 0.18 mm is removed in two working steps. The roughing (ap = 0.15 mm) is performed with a feed rate fz of up to 0.7 mm and a cutting speed of 200 m/min. The same insert then performs the finishing with fz 0.4 mm and vc 240 m/min. With the conventional turning process, feed rates of only 0.1 – 0.2 mm could be achieved. The blade today reliably achieves a tool life of 2,000 parts. Of particular note, however, is the machining time per part: It totals just 6 seconds.
Compared with conventional machining, rotational turning allows a reduction in the machining times of more than 70% – with higher process reliability and longer tool life.