Gear Technology Magazine
www.geartechnology.com/articles/24967

IMTS Preview: Index Traub

June 24, 2014
The new Index G220 Turn-Mill Center includes a motorized five-axis milling spindle and a tool turret with Y-axis, providing maximum machining flexibility for turning and milling complex parts in a single setup. Index will demonstrate the machine at IMTS 2014, Booth S-8136. With a distance of 1,280 mm between the main and counter spindle and a maximum turning length of 1,000 mm, the G220 provides a generous work area. Operators have easy access to the main and counter spindles, the turret and the motorized milling spindle, as well as the operating panel. The fluid-cooled, identical main and counter spindles feature a clearance of 65 mm (chuck up to max. 250 mm diameter), and provide power of 20/ 24 kW, a torque of 135/ 190 Nm and a maximum speed of 5,000 rpm. A tool turret is located in the lower part of the machine, can accommodate VDI 25 and VDI 30 tool mountings in 18 or 12 stations, all of which can be equipped with individually driven tools (power 6 kW, torque 18 Nm, speed 7,200 rpm). The fluid-cooled five-axis motorized milling spindle (power 11 kW, torque 30 Nm, speed up to 18,000 rpm) has hydrostatic bearings in the Y/B-axes. The stable circular guide further ensures excellent rigidity and damping. The Y-axis features a +/-80 mm stroke, the B-axis driven directly by a torque motor has a swivel range of -35 to +215 degrees. With a large travel distance in the X-direction, machining at up to 30 mm below the turning center height is possible. The motorized milling spindle operates using a one or optionally two-row tool chain magazine which features space for 70 or 140 tools (HSK-A40). The double-row tool magazine enables setup during machining time. The compact machine features a CNC-controlled programmable gantry-type removal unit for finished workpieces. It can unload remnants from the main spindle as well as finished parts from the counter spindle. The G220 presents a particular highlight when it comes to user friendliness and process reliability with the latest generation of the Index C200 SL controller. Based on the Siemens Sinumerik 840D sl (solution line), it features an 18.5 inch touchscreen. Additionally, the new Traub TNK42 automatic lathe will have its North American debut at IMTS 2014, Booth S-8136. Developed for high production precision turning, the new 42-mm TNK42 fixed headstock automatic lathe adds to the series of CNC fixed/sliding headstock automatic lathes, the TNL18 and TNL32. The time-saving new machine is for production of turned parts up to 250 mm in length and of geometrically complex workpieces in large and medium volumes. With two tool turrets, a main spindle with C-axis and 42 mm bar capacity (7,000 rpm, max. 29 kW and 65 Nm) and a swivel counter spindle with C-axis for extensive rear end machining, the TNK42 offers high production rates with only 5.5 m2 footprint (without bar loader). The vertical design of the machine with a setup-friendly work area permits unobstructed chip flow and better ergonomics for setup operations. The stable, vertical cast machine bed is mounted on a heavy cast iron machine base, providing excellent damping properties for high-precision cutting. The upper tool turret has 10 stations with slide travels of 140 mm in X and 300 mm in the Z axis. All stations in the upper turret can be equipped with live tool holders. Turret indexing is accomplished with an NC rotary axis with a direct measuring system, avoiding the need for any mechanical lock, thereby allowing fast positioning of the turrets at any angle. This way, multiple tools can be assigned to each station, so that the upper tool carrier can be equipped with up to 20 tools. The standard built-in Y-axis for the two turrets is formed by the interpolated movement of the CNC turret indexing H-axis and simultaneously the C-axis of the work spindle as well as the X-axis of the tool carrier. Through this combined motion along with the powerful tool drives (with max. 5 kW/8 Nm/12,000 rpm), the TNK42 provides a large Y-travel for all turrets, e.g., to mill surfaces and grooves on workpieces or to drill axis-parallel off-center holes. Traub has also reduced idle time with its innovative optional “Dual Drive” system for the upper turret, where two separate drive trains are used to ramp up the speed for the next tool while still cutting with the current tool. This means the new tool is indexed to the machining position at full speed, reducing secondary processing times, and extending the service life of the live tool holders. Processing versatility Apart from its function as a lower tool turret with 9 stations and identical functionality as the upper tool turret, the lower cross-slide serves as a swivel counter-spindle for rear-end machining of workpieces. The swivel movement of the counter spindle is achieved through the CNC turret indexing axis (H-axis), thereby providing a counter spindle with a C-axis that can be moved in three axes (X/H/Z), allowing unrestricted counter spindle machining at 7,000 rpm (max. 12 kW and 22,5 Nm) and 42 mm spindle clearance.