Debut of the Optimal Large, Precision CNC Turning Center : the NLX 6000
DMG MORI CO., LTD. (hereafter “DMG MORI”) has started sales of the NLX 6000 | 2000, a high-rigidity, high-precision NLX 6000 Series CNC lathe with a distance between centers of 2000 mm, from December 14. The NLX 6000 | 2000 offers a lineup of three spindle types for a diversity of workpieces, and is the optimal large, precision CNC turning center for large-diameter shaft machining in the aerospace part and energy fields.
The NLX 6000 | 2000 is a CNC lathe available in a total of nine variations achieved by combining each of three spindle types differentiated by through spindle hole diameter – the B type (f185 mm), C type (f285 mm) and D type (f375 mm) – with the 2-axis turning specification, MC specification or Y-axis specification. With its large-diameter spindle and generous machining area, it is the optimal machine for machining long, large-diameter workpieces up to f920 mm in diameter and 2,000 mm in length. It is equipped with functions and features suited to heavy-duty cutting of difficult-to-cut materials, including a high-rigidity bed and comprehensive thermal displacement control, allowing high-speed, high-accuracy machining of long, large-diameter workpieces.
We would like to highlight the main features of the NLX 6000 | 2000 from the perspectives of: (1) High rigidity, (2) High productivity through multi-axis machining, (3) High precision, (4) Operability / Maintainability, (5) Energy savings, and (6) Safety.
(1) High Rigidity
A highly rigid machine construction supporting heavy-duty cutting of difficult-to-cut materials was created by adopted methods including simulating torsional rigidity using FEM analysis.
Slideways have been employing for the X-, Y- and Z-axis, improving vibration damping performance and dynamic rigidity. In addition, the X-axis is equipped with large-diameter ball screws of f50 mm, giving improved feed rigidity. This high-rigidity construction allows powerful machining of ultra-heavy workpieces.
(2) High Productivity through Multi-axis Machining
The turret has a capacity of up to 12 tools and adopts BMT (Built-in Motor Turret) technology, where the motor is built into the turret (with the MC specification and Y-axis specification), to minimize heat generation/vibration and improve milling accuracy when compared to the turrets of conventional machines. In milling the cutting performance equals or exceeds that of machining centers with a No. 40 taper spindle and the rotary tool spindle has a maximum torque of 117 N×m (10% ED).
The spindles achieve an output of 45/37 kW, torque of 7,021/12,069/12,082 N×m (B/C/D type) in the standard specification thanks to a robust construction with an integrated beltless-drive motor, surpassing the performance of the high-output/high-torque specifications of conventional machines.
(3) High precision
As for the thermal displacement control that has a major influence on machining accuracy, oil jacket cooling is provided around the spindle motor and the built-in motor to suppress temperature rise. A cooling system is also provided for the heat sources in the headstock and the vicinity of the Z-axis ball nut. As a result, stable high-precision machining over prolonged periods is achieved by comprehensively controlling thermal displacement.
ABS magnetic linear scales manufactured by Magnescale are equipped for efficient high-accuracy positioning. A direct scale feedback system can be featured as an option. Magnetic linear scales have better anti-vibration and anti-shock characteristics than optical systems and are also less susceptible to the condensation and oil contamination that are inevitable with machine tools, and can therefore deliver high accuracy with a resolution of 0.01 μm in challenging environments. What is more, the magnetic linear scales have the same linear expansion coefficient as the cast iron used for the structural components of machine tools in general, and show the same thermal displacement as the machine tool on which they are mounted, so they maintain extremely stable machining accuracy even in environments subject to temperature changes.
The machine has been designed based on thorough analysis of the customers’ demands and attention on improved working efficiency from the perspective of maintainability, and ease of maintenance, and the newly equipped steady rest quick change system (option) greatly improves setup change work: changes that conventionally took around 8 hours are accomplished in around 0.5 hours, substantially shortening setup change times.
A wide door opening of 2,600 mm is secured for improved operability during setup operations. In addition, the cover above the chuck is provided with a pocket to accommodate tool overhang, preventing interference.
The oil chiller, hydraulic unit and pneumatic equipment are centralized for easy maintenance.
All parts can be inspected easily and the machine can always be operated in the best condition, which greatly assists customers to improve their productivity.
(5) Energy Saving
In an effort to reduce environmental burden and running costs, the machine incorporates energy-saving functions and designs to achieve high-speed operation of various mechanisms. As for energy-saving functions, we have adopted energy-efficient components such as LED in-machine lighting, and have strengthened the functions for energy savings during automatic operation, including a function that adjusts the coolant discharge rate according to the machining load, and a function that shuts off the power to systems that are on standby. All mechanisms have also been designed for increased speed, and we have managed to cut cycle times by optimizing M codes and by developing features such as a function to reduce the operation times of canned cycles.
Ingenious measures like these translate into an annual reduction in power consumption of approximately 31%*1 compared, for example, to one of our machines that is now due for replacement after 15 years or more in service.
The CELOS energy savings application enables energy savings setting and visualization of energy saving effects.
*1 This figure is the result of comparison between our SL-603BMC/2000 lathe manufactured in the year 2000 and the latest NLX 6000BMC | 2000.
●The effect indicated above may not be achieved depending on the machine, cutting conditions, environmental conditions at measurement, and other conditions.
The NLX 6000 | 2000 complies with safety standards all over the world, including ISO standards, IEC standards, UL standards and JIS standards.