Ultrasonic Machining Center Can Be Equipped with 1,500-rpm Turning Table
DMG MORI’s second-generation Ultrasonic 20 Linear extends the company’s offering of ultrasonic machining centers. Oscillating contact interruption results in improved lubrication and cooling of the cutting edge as well as increased removal of particles from the active zone. This enables longer tool life and surface qualities ranging to under 0.1 micron Ra on hard, brittle, difficult-to-machine materials. According to the company, the machine offers high material removal rates, accurate edge machining and reduced process forces in the machining of advanced materials such as glass, ceramics, corundum, composite materials and hard metal. The machine is designed to minimize deflections while increasing workpiece accuracy and process reliability for users in the optical, clock and watch, medical, and high-precision mold construction sectors.
The machine is now capable of handling larger tool diameters ranging to 2.0". Maximum workpiece weight is 33 lbs, increased from 22 lbs in previous versions. The basic machine is equipped in with a 19-kW, 42,000-rpm motor spindle and HSK-32 toolholder. Higher speed requirements are met with an optional spindle that offers 60,000 rpm. An HSK-40 spindle, optionally with permanent grease lubrication, is also available.
The machine can be equipped with a 1,500-rpm mill-turn table, which expands complete machining to include milling, turning and grinding of rotational-symmetrical components in a single setup. In addition to the standard 24-fold toolchanger with pickup, the chain magazine is optionally available for 60 tools.
Other features include a digitally-controlled ultrasonic generator as well as ultrasonic actuators with enhanced performance, the company says. Toolholders with adapted actuator technology are changed into the milling spindle automatically. Each of these holders contains piezo elements, which are activated by a program-controlled inductive system with a frequency of 20 to 50 kHz. Tool rotation is superimposed with an additional tool movement in the longitudinal direction so that a defined amplitude ranging to 10 microns, which can be programed in the NC program, is generated on the cutting edge of the tool or on the grinding layer.
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