German high-precision machine tool manufacturer Thielenhaus Microfinish said it is now capable of machining crankshafts for engines with three to six cylinders, in some cases even without major retooling via the use of its CrankStar machine.
In addition to centre and pin bearings and thrust faces, the CrankStar can finish oil seal diameters and deburr bores in the flange. Thrust face machining occurs via a special unit while the workpiece is oscillated.
Even with vertical machine concepts, the CrankStar comes with up to 33 per cent longer intervals between tool changes than the industry standard, featuring a tape capacity of 300+ metres.
The vertical solution allows a quick belt change from the front of the machine, without requiring the withdrawal of an entire tool carrier package.
In addition to the conventional hard or soft shoes, Thielenhaus is developing a shoe that uses a kind of belt system to adapt to the component’s size.
With the DiaFlex technology, crankshafts with the same bearing widths but different diameters can be machined without swapping the shoes.
In practice, it often happens that, due to higher torques in three- or four-cylinder motors, a few millimetres more of bearing diameter are needed with the same motor concept and gauge.
The DiaFlex shoe adapts to the respective diameter and can compensate for differences of up to 15 mm without changing shoes.