Five multiplied by two axes are more productive

The usual practice is to premecanizar the wheels made with bars forged in the centres of turning. Then end the geometries of the blades in HSC machining centers. Like this it is only possible in five axes, so far, and because of the need of a high-precision machines are used with a single spindle with automated loading. So, productivity can only increase through additional machining centres. However, this is too expensive. They should facilitate and also install all peripherals, such as media holding, industrial robots, receiving stations, pallets and supply and collection devices.

Essential improvements through the production can be carried out with dual spindle machining centres. For this reason, Schwäbische Werkzeugmaschinen GmbH is now in Waldmössingen practical production processes for these machines. Sliced prefabrican as usual in centres of turning. As an interface between the devices of subjugation of the centres of turning and machining and the slices used an HSK. To this end, a tensor mandrel collects in the HSK slices his central perforation. This drilling is machined to close tolerances due to its functional nature, required by the concentricidad of the 'impeller'. It is therefore perfectly centered, aligned and round. For the machining of the 'impeller', an industrial robot respectively introduces two subject slices in the HSK on devices of the bars of subjection of the machining with double spindle BA321 Center. The accuracy of the change of the HSK conical mandrel to hold them is less than 5 µm. Devices in the bars of subject are developed on five axes NC (axes of rotation) and are arranged, as well as the main spindle, in 300 mm distance. The subject bar turns as a fourth axis to power machining simultaneously on five axes the geometries of the blades.

BA321 machining center works with two spindles of high speed reaching 42,000 rpm. They are in a robust head block which moves vertically through the portico on the well-known principle 'box-in-box'. The propulsion of the porch seeks to high precision even with eccentric loads. The routes of displacement amount to 300 mm X 500 mm in and and 375 mm in Z. The spindles of balls with lubricated ball guides make possible speeds of up to 70 m/min displacement direction and z and up to 60 m/min in X direction, with accelerations of up to 10 m/s² in the X and Z axes and up to 8 m/s² on the shaft and. String to 2 x 20 loader tools is located above the workspace. The head moves about 250 mm up to Changer tool pick-up in the magazine space that is separated from the work area by sliding doors. The tools are therefore optimally protected from chips to go flying. First pick-up, the machining center makes times 'chip to chip' less than 3 seconds. The E50 HSK tool is best suited for the high number of revolutions. They are completely symmetrical to the axis of rotation with drag slots.

To ensure rigidity and stability, the machining center runs as a monobloc. This allows in addition a very compact construction. The monoblock are integrated all the other components, so this is a very compact machine. Also is you can quickly access without any problems all propulsion components from the rear.

Large sliding doors allow free access to the work area. Thus, an industrial robot can take without problems with its double gripper two 'pump' and insert two slices after turning its pincers. This process of production - machined parallel of two 'pump' - machining center around achieves a 30% more productivity in comparison with machining with a single spindle. Thus, this way of producing saves often the need to provide an additional machine and peripherals, industrial robots, stacks of pallets, transfer stations, necessary to do so.

BA321 machining center offers the convenience of programming and management thanks to the modern CNC Siemens S840 D Solution control line. He integrates functions and special features of the simultaneous machining of five double spindle shafts. Thus, the programmer and the user can access them through graphic dialog boxes. Also, the control works considerably faster than other controls of the NC programs for five-axis simultaneous machining. Special calculation cycles increase the accuracy of the route. Thus the dynamics of BA321 machining center can take full advantage. This also contributes to higher productivity of machining with two spindles of the 'impeller'. In addition, five axis simultaneous machining provides the greatest flexibility for changing geometries of blades. Thus commissioned productions alternate with series of pump with a minimum time of equipment can be machined with profitability.