Modern Machine Shop is focused on all aspects of metalworking technology - Providing the new product technologies; process solutions; supplier listings; business management; networking; and event information that companies need to be competitive.
Issue link: https://mms.epubxp.com/i/850702
26 MMS August 2017 mmsonline.com RAPID TRAVERSE Machining Technology in Brief What's Low-Frequency- Vibration Turning? BY D E R E K KO R N tooling rather than high speed steel. This provides the flexibility to not just consolidate operations, but to choose the balance between gear quality and production speed. Longer-lasting carbide tools, he explains, can spend more time in the cut at slower feed rates in order to impart smoother surface finishes. In contrast, HSS might require more aggressive feeds that avoid burning up the tool but leave a comparatively rougher finish. The CNC also features a conversational pro- gramming interface specifically (and only) for the skiving function. Through a series of queries about angles and geometries, this system prompts the user to enter enough information to virtually define any spline or helical or straight gear (beveled gears, hypoid gears and worm gears require other processing options). In addition to the flexibility of an HMC, avoiding the need to purchase dedi- cated software can potentially make it easier for virtually any operation to take control of its own gear manufacturing. "The machine is geared for high volumes, but it's still a great fit for a job shop," Mr. Terry says. Toyoda Americas Corp., call 847-253-0340 or visit toyoda.com. I n most cases, turning operations involve con- tinuous cuts in which the tool remains engaged with the material from the time it starts the cut to the time the cut is completed. Marubeni Citizen- Cincom has developed what it calls low-frequency- vibration (LFV) technology, which is available on its L20 sliding-headstock Swiss-type lathes. This technology purposely oscillates the cutter in the Z axis in time to the rotation of the barstock. At times, it actually brings the cutter completely out of the cut. The company says the advantage of this pro- grammed oscillation is that the intentional "air cuts" break the chips into small pieces so they can be readily expelled, minimizing the problems of spiraling chip entanglement around the work- piece, known as "bird nesting." This strategy is said to be particularly effective in controlling chips/preventing bird nesting when turning materials such as copper, plastic, Inconel and stainless steel—a challenging task for con- ventional turning operations. Additional benefits are said to include increased cutting tool life, minimized buildup on cutter edges, and reduced heat generation and power consumption. In addi- tion, the same type of cutting tools a shop would use for conventional turning can also be used for LFV turning, the company says. The video at short.mmsonline.com/ lfv demonstrates the concept, showing the changing amount of cutter engage- ment with the material as it oscillates. To make a 90-degree square shoulder, the oscillation stops and the tool is Low-frequency-vibration turning oscillates the cutter in the Z axis. Intentional "air cuts" break chips into small pieces, pre- venting the formation of long, stringy chips.