The trend towards single set-up CNC machining of ever more-complex and higher-quality components means that multi-tasking machine tools are essential in order for manufacturers to remain competitive, especially when producing small batch sizes of multiple part variants.
The 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.
Despite weighing 23 tonnes, this machine — available in the UK and Ireland through sole agent Kingsbury (www.kingsburyuk.com
) — does not need any special foundations, as the polymer monobloc bed has very high inherent mechanical stability; and with generously dimensioned linear guideways in the X and Z axes, the machine also has good damping properties.
High levels of precision are ensured by the thermal stability provided by extensive cooling circuitry throughout the machine structure, moving elements and peripherals.
Workpieces up to 1.6m long can be machined from bar up to 102mm in diameter; the chuck diameter is 315mm (optionally 400mm).
The G420 features a 26kW 12,000rev/min milling spindle that moves in the X, Y, Z and B axes at the top of a vertical bed; the spindle is fed from a 58-position (optionally 115-position) magazine for HSK-T63 or Capto C6 tools.
A Y-axis stroke of ±170mm, a B-axis swivel of ±115deg and an X-axis travel of 750 mm — plus the Z-axis movement and a C axis on both the main spindle and the counter-spindle — allow up to five-axis simultaneous machining.
There are two X/Y/Z turrets mounted on vertical guideways below the centre-line between the 34/41kW main spindle and the identical counter spindle; and since each of the lower tool carriers is equipped with 12 live tool stations, there are enough tools for the most demanding jobs without the need for additional set-ups.
Both turrets can 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 handling unit is available for loading and unloading parts weighing up to 20kg and up to 120mm in diameter, although various other automation solutions are available.
Control is by an adapted Siemens 840D sl operated via the Industry 4.0-compatible iXpanel system from Index.