For many years, DMG MORI has been offering high-performance machine tools with ULTRASONIC technology for 5-axis machining of complex workpieces made of advanced materials.
With the new ULTRASONIC 20 linear, this series now captures a completely new class. Spindle speeds with optionally up to 60,000 rpm, more powerful drive motors, an even smaller footprint plus CELOS with apps specifically developed for the ULTRASONIC are all part of the innovations which users from the fields of optics, precision engineering and clocks, medicine and high precision mould manufacturing will benefit from in the future.
Reduced process forces for filigree structures, surface qualities up to Ra <0.1 μm and longer tool service life
Included with the most important technological innovations of the ULTRASONIC 20 linear are a new, completely digitally controlled ultrasonic generator and the ULTRASONIC actuators with higher capacity and rotational speeds of up to 50,000 rpm. The tool holders with adapted actuator technology can be easily and fully automatically replaced in the milling spindle. Each of these holders is equipped with piezo elements, which are activated via a program-controlled induction system with high frequency between 20 and 50 kHz. The original tool rotation is thus superimposed with additional tool movement with defined amplitude in longitudinal direction. The resulting deflection of the cutting edges or grinding areas is controlled via the NC program and can be in a range of up to 10μm or even higher. During grinding, drilling and milling, these superimposed vibrations have a direct, positive impact on the process forces, the removal volume and the tool service life and thus result in reduced costs and higher productivity.
In detail, the ULTRASONIC technology achieves a higher removal volume, more precise edge processing and up to 40 percent reduced process forces during machining of advanced materials like glass, ceramics, sapphire, hard metal and composite materials as well as carbide. The precision of the workpieces and reliability of the process are increased at the same time. Furthermore, the oscillating interruption of the tool contact with the workpiece results in an improved lubrication and cooling of the cutting edges and the optimum removal of stripped particles from the work area. The outcome is longer service life of the tools and excellent surface quality of up to <0.1 μ for hard-brittle high-performance materials. The ULTRASONIC 20 linear ideally combines high speed cutting with highly efficient ULTRASONIC grinding of advanced materials on a single machine. It enables the machining of an unprecedented range of different materials.
Intelligent ULTRASONIC technology with process-optimized amplitudes
“ULTRASONIC Parameter Detection” of the ULTRASONIC 20 linear ensures automatic detection of the ultrasonic frequency most suitable for the actuator and tool with powerful functions for process monitoring. Another function used for the first time worldwide is the monitoring and tracking as well as of frequency and amplitude during the ongoing machining process. For this purpose, UAT (Ultrasonic Auto Tuning) automatically tracks the frequency response and compensates all exterior influences like the dampening of ultrasonic vibrations by means of the primary process forces. This way, a consistent readjustment to the nominal amplitude or the value specified in the NC program can be achieved. With this, users can fully exhaust their processes and increase tool utilization, reduce cycle times and, particularly by reducing the process forces, achieve even more filigree, precise and high quality machining results.
Highly dynamic, long-term stable 5-axis machine concept – compact on just 3.5 mÇ footprint
With the ULTRASONIC 20 linear, DMG MORI relies on a long-term stable gantry machine design, to be able to safely meet all demands of ultrasonic machining. Despite this, the machine tool manufacturer was able to reduce the footprint of the machine to only 3.5mÇ. A double drive for the Y-axis and the concept of integrated cooling, which uses the temperature monitoring of drives, spindles and the control as well as all media guarantee highest precision and workpiece quality. The linear measuring systems from MAGNASCALE are a good example for the high-tech components which DMG MORI has used here.
DMG MORI has significantly increased the capacity of the drives for the new development: by 47 percent for the A-axis, 27 percent for the C-axis and 34 percent for the Z-axis. The linear drives achieve maximum acceleration of more than 2 g and provide rapid traverse speeds of up to 40 metres per minute. Due to the large swivel range of the A-axis of the work table, ranging from -15° to 130° and the fully integrated 360° endless rotation axis – both with torque technology, the ULTRASONIC 20 linear is optimally suited to 5-axis simultaneous machining. The rotational speed of 1500 rpm that can optionally be achieved for the C-axis also enables circular milling/circular grinding as well as turning/milling operations.
After the revamp, the ULTRASONIC 20 linear can now be used with larger tool diameters of up to 50mm and an increased maximum workpiece weight from 10kg to 15kg. The basic version of the machine is equipped with a powerful 15 kW motor spindle and a HSK-32 tool holder, the maximum rotational speed is at 42,000 rpm. Higher demands on the rotational speed can be achieved with an optional spindle, which reaches an impressive 60,000 rpm. The range in this segment is rounded off by an HSK-40 spindle with permanent lubrication.
The modular concept of DMG MORI enables a wide-ranging application-specific configuration of the machines – of course this also applies to the ULTRASONIC 20 linear. For example, the machine can be supplied with a 1,500 rpm turning/milling table, which extends complete machining of rotation-symmetric workpieces in a single setup to the operations of milling, turning and grinding. In addition to the tool magazine with 24 pockets and minute wheel, a 60-pocket chain magazine is optionally available.
Unique integration of technologies
The ULTRASONIC 20 linear with its special features enables the use of ultrasonic support for specific materials, namely the milling and drilling of nickel or titanium super alloys or of materials like magnesium, tungsten as well as composite materials. Process forces have been reduced for milling applications in titanium by up to 30 percent. For steel, double feed speeds are possible, for other materials, like magnesium, the feed speeds can be increased by up to five-fold. In addition, an improved surface quality can be achieved. The ULTRASONIC process has a significant impact on chip breaking behaviour and chip removal from the tool. Further to shorter chips, this also results in drastically reduced tool wear, making the technology interesting for almost all future-oriented target markets with high-tech products. The specific benefits associated with the option of using the ULTRASONIC technology have also taken the flexibility to a new level. It is now possible to machine workpieces from very different materials from soft to hard-brittle, in five axes for mould making, medical technology, the automotive and aerospace industry.
ULTRASONIC 20 linear with new design and CELOS
High-quality, long-lasting covers as an external distinguishing feature with functional added value thanks to optimum accessibility are the most important properties of the new standardized DMG MORI design. The ULTRASONIC 20 linear also has this new look, whose impact on value retention must not be underestimated and furthermore, the machines offer CELOS. This user interface with its unique multi-touchscreen can be used as easily as a smartphone. The user friendliness is further increased by CELOS apps which were specifically developed for ultrasonic machining. They visualise the ULTRASONIC technology cycles and the most important process parameters like frequency, amplitude and output power. At the same time, the apps monitor the process forces of the actuators and also support configuration of the tools.