German lathe manufacturer, INDEX, has introduced a new turning / milling centre, designated R300, incorporating two independent 5-axis machining systems. Sole UK agent, Geo Kingsbury Machine Tools, says that the machine is geared toward the manufacture of larger chucked parts requiring significant milling and drilling, such as in machinery construction, tool and mold making and the aerospace industry.

This unusual level of versatility is provided by two B-axis milling spindles working in conjunction with the main and counter spindles respectively. The configuration is a cost-effective alternative to using two multi-axis machining centres with turning capability for the production of complex components up to 315 mm diameter when chucking or up to 102 mm if using short bar. The machine joins the existing, smaller R200 model, which caters for 175 mm chuck parts and 65 mm bar.

Emphasis has been placed on a high degree of thermal stability, exceptional stiffness, impressive dynamic response and vibration damping to enable machining of difficult-to-cut and high-strength materials. These characteristics are achieved by a vertical, heavily ribbed cast machine bed with the two quill-guided milling spindles placed one above the other in the centre and the main and counter spindles arranged diagonally.

Two linear tool carriers are attached to both sides of each milling spindle, providing a total of 12 stationary tools. It means that tool changes are no longer necessary for static turning operations, reducing cycle times. Rapid exchange of HSK tools between the milling spindle and magazine, which can contain up to 140 cutters, enables chip-to-chip times under 6 seconds. The two milling spindles perform tool changes independently of each other. Through-tool coolant delivery at 80 bar supports difficult machining operations including hobbing and deep-hole drilling. Even grinding using wheels up to 150 mm diameter can be included in the machining cycles.

Heavy-duty roughing operations can be carried out at the main spindle while entirely different, highly accurate fine-turning operations are performed simultaneously at the counter spindle; or alternatively, identical operations can be carried out at both ends.

Other plus points are the high accelerations and 45 m/min rapid traverses supported by powerful drives and weight-optimised assemblies, and the generous B-axis swivel ranges of 270 and 230 degrees. The turning spindles have a maximum power rating of 47 kW, a maximum speed of 3,500 rpm, and a peak torque of 690 Nm.

The C200-4D SL control is based on the proven Siemens Sinumerik S840D with INDEX customisation. VirtualLine software supports economical use of the new multi-axis mill-turn centre, guiding the programmer and operator to the correct solution for the machining task. In conjunction with 3D simulation, machining programs can be created, checked, and optimised on a PC. CNC Programming Studio provides more advanced support for programming and operation.

The INDEX R300 is designed to support energy efficiency, including: weight-optimised components for reduction of energy consumption and for increasing the dynamic response; energy recovery by means of regenerative drives; shutdown of units that consume large amounts of energy after a user-defined time; minimised friction based on optimally paired materials and low-friction hydrostatic bearings; intelligent cooling of the machine, and economical use of waste heat.