To demystify power skiving, the following provides approximate yet valid ways to calculate required spindle speeds, which is key in machine and tool selection, as well as guidelines on what components are suitable for power skiving. To make power skiving a widely used method in gear and spline production, basic understanding of the method is needed.
Software now exists to define the form of the tool and the resulting component geometry, yet no basic rules of thumb or formulas are available in handbooks for the gear manufacturing engineer wanting to make a fast analysis on the viability of power skiving a particular component. The recent development in machine controls, machine hardware, and tool design have made it possible to apply the idea from 1910 on an industrial scale for making gears and splines.
This article explains the fundamentals of power skiving in order to guide manufacturing engineers and decision-makers to determine when power skiving can be a suitable solution by using some simple mathematics and rules of thumb. Still, an understanding of even the basic principles may not be common knowledge within either the gear manufacturing or the general machining community. The same Japanese authors also published a JSME (Japan Society of Mechanical Engineers) paper where they describe gear skiving as a “high productivity method to produce internal gears with rotating tool.” There were few published works until about 2010 when literature appeared in forums such as The International Academy for Production Engineering (CIRP), International Journal of Advanced Manufacturing, American Society of Mechanical Engineers (ASME), and others, where power skiving was dissected and explained in sometimes quite heavy mathematical terms. Following a somewhat dormant period, a U.S. The initial solution was developed and patented in 1910 in Germany. You can find the complete interview (in German language only) as a video on DMG MORI's Youtube channel under the following link: interest and successful application in power skiving is increasing within the gear manufacturing community as well as within companies that have access to modern five-axis machines but, thus far, have outsourced their gear manufacturing.
The machines are also part of the state-of-the-art machinery in Sonthofen to ensure the required quality grades of the special gearboxes and drive elements.
The HerkulesGroup has been working with DMG MORI machines at its various locations for years, for example with the CTX TC series complete turning/milling machining center for machining complex workpieces. In addition, we don't have to outsource production, but can manufacture all gear parts in-house without having to rely on an external supplier." Here, too, we have had the machine retrofitted with the appropriate software so that we can drastically minimize the idle times of our parts. Senoldu: „With gear skiving, a combination of gear hobbing and gear shaping, gears can be produced in series on turning/milling centers with the highest productivity and quality. Thanks to the GearMill software, in addition to all common types of gears, we can set the appropriate inclination angle for the palloid milling operation so that the operation can be carried out, taking into account the appropriate tools for the milling process in question." Such milling operations are performed at RSG on the DMU80 FD. For this to be successful, the module must have a certain inclination in order to be able to mill gears for so-called helical or spiral bevel gears. However, in both cyclo-palloid and palloid milling operations, the tool must mill helical gears. Normally, in the gear manufacturing milling process, the module is straight. Senoldu: "The principle of cyclo-palloid gearing is based on two eccentrically arranged cutter head groups, which have radii of curvature of different sizes.
How should one envision the software update and the interaction with the machines? By retrofitting the machines with the appropriate software, we can also guarantee our customers a wide spectrum in parts production at all times." They are therefore the perfect complement to ensure our high standards in the production of our gearbox solutions. Thanks to the machines from DMG, we are able to use our turning-milling machines for cyclo-palloid gears and gears and splines in addition to our gear cutting machines (gear milling and shaping). Senoldu: "The best way to see us is as a customer and partner alike. Senoldu, how exactly would you describe the cooperation between DMG MORI and RSGetriebe?