Mindful of this, German lathe manufacturer Index has introduced a new turn-mill centre, the G420, capable of producing large components in one hit within a compact footprint of about 15m2. Availability in the UK and Ireland is through sole agent, Kingsbury.
Despite weighing 23 tonnes, the machine does not need any special foundation as the polymer monobloc bed has very high inherent mechanical stability. The lathe offers the best deflection resistance of any comparable machine on the market and, with generously dimensioned linear guideways in the X and Z axes, has good damping properties. A ratio of static masses to moving masses of greater than 5:1 not only provides excellent stiffness, but also enables highly dynamic movements with low vibration.
Workpieces up to 1.6m long can be machined from bar up to 102mm in diameter, while chuck diameter is 315mm (optionally 400 mm). Top precision results are assured due to the thermal stability provided by extensive cooling circuitry throughout the machine structure, moving elements and peripherals. Stored energy can be used for other purposes such as additional process steps or heating the user's factory.
The G420 features a 26kW / 12,000rpm milling spindle moving in the X, Y, Z and B axes at the top of a vertical bed and fed from a 58-position (optionally 115-position) magazine for HSK-T63 or Capto C6 tools.
The Z-axis slideway of the milling spindle and the Y/B axis with hydrodynamic bearing support and linear scale feedback of quill movement are symmetrically designed for stability. A Y-axis stroke of ± 170 mm, B axis swivel of ± 115 degrees and large X-axis travel of 750mm, together with the Z-axis movement and C-axis on the main / counter spindle, allow up to 5-axis simultaneous machining of complex components.
There are two X/Y/Z turrets mounted on vertical guideways below the centreline between the 34 /41kW (100% / 40% DC) main spindle and the identical counter spindle. The overall design ensures excellent chip flow away from the machining area into a conveyor that can be mounted to the left or right so that a manufacturer can optimise use of floor space.
Since each of the lower tool carriers is equipped with 12 live (7.5kW / 5,400rpm) stations, more than enough tools are available for the most demanding jobs without the need for additional set-ups. The turrets are equipped with the VDI 40 tool interface with W-serration and both can be moved not only in the X and Z axes, but also ± 70mm in Y.
Both turrets are able to work at either spindle position and if a static turning tool is mounted in the upper motor spindle, three tools can be in cut simultaneously. Alternatively, a steady can be mounted in one of the turrets to assist in machining shaft-type components with the other two tool carriers.
An integrated, 2-axis handling unit is optionally available for loading and unloading parts up to 20kg and 120mm in diameter. Further automation solutions involving robotic handling and conveyor systems can be integrated to meet specific needs.
