IMTS 2014: Somewhat Unique, Always Challenging
As the old saying goes, if top-notch gear making was easy, absolutely everyone would be doing it
Gears are a somewhat unique product, said Alan R. Finegan, director, marketing, Gleason Corp. (Rochester, NY), however, “the processes used to produce them are still metalworking processes. Changes in gear making are likely to mirror those in the broader metalworking industry. Like many industries, gear manufacturing is a very mature industry and changes tend to be evolutionary rather than revolutionary.”
What revolution is taking place in gear making stems from the fact gear making has its roots in metalworking. Thus not all companies offering machines capable of making gears will be found in the Gear Generating Pavilion at IMTS. A fair number will be found in the Metal Cutting Pavilion. For the most part, these CNC machine tool companies are targeting job shops that are contracting to manufacture a variety of parts and that may not need to do high-volume machining of gears all the time.
But, as Finegan said, gears are a somewhat unique product. Those interested in dedicated high-volume production of gears and/or gears that require additional pre- and post-process operations should head to the North Building, where the companies with that expertise—and traditional, special-purpose gear making machines—are to be found.
“The trends driving innovation in the gear industry,” Finegan said, “are … the customer’s need for higher quality, more flexibility, lower costs, and, when investing in plant and equipment, lower total cost of ownership (TCO). Innovations in processes, equipment, tooling or software that do not address one or more of these issues are probably not valued by the market.”
Going forward, he noted, “We expect that there will be incremental advances in materials and coatings, metrology and analysis, flexible and tool-less workholding, and automation. There will be continued emphasis on designs and processes for ever-quieter gear sets, including more and improved fine finishing processes.
“Gleason’s mission has been and remains to be The Total Gear Solutions Provider. As such, we provide solutions to our customers that allow them to be better and more competitive gear producers. This means that we provide not just processes, machines and tools, but also the complete array of aftermarket products, services, software and education in the form of training and seminars.”
Such support is sought after by industries, such as energy, that require highly specialized gears. For a look at gear making for this industry, please visit http://tinyurl.com/gears4energy. Automakers also need this sort of support because they have an additional need: to meet governmental fuel economy standards. In addition, they need more gears to do so.
For example, Chrysler reports its new eight-speed automatic transmission paired with its 5.7-l V8 weighs a mere 8 lb (3.6 kg) more than its five-speed predecessor but delivers 5% better fuel economy. That’s a significant step on the way toward meeting fast-approaching increases in federal requirements.
Liebherr Gear Technology (Saline, MI) is a key supplier of gear making equipment to the motorized vehicle industry. A few of the trends it has noticed among its customers include the growing importance of finish hobbing and chamfering of tooth flanks and an increased desire for productivity in the hard finishing of gears, particularly generating grinding. “With gear grinding, we have seen new abrasives, such as 3M’s Cubitron-II, become available that afford higher axial feed rates, more parts per dressing, and low risk of grinder burn. The results have been reduced cycle times and increased tool life,” said Scott Yoders, Liebherr’s vice president of sales.
“From the machine tool point of view, these new gear grinding abrasives require an extremely rigid design. In particular, the grinding head stiffness is of utmost importance in order to really unlock the full potential of the abrasives. That is what our LGG series of grinders were designed for.”
In addition, he said, the chip-to-chip times on the LGG’s single worktable gear-grinding solution (down to 4 seconds) yield the highest levels of productivity for high-volume gear grinding applications. With a single worktable, not only do customers need to invest in less workholding tooling, but managing machine offsets and workpiece quality (Cpk) becomes less complicated with a single stream of variation, purely from a statistical point of view. Other trends to look for in gear manufacturing at IMTS, he noted, include increasing levels of automation for the gear production process from low to high volumes, and integrated chamfering methods for tooth flanks, which can be done in parallel to the hobbing process. ChamferCut, pioneered by Liebherr in 2005, can now be done in parallel to the hobbing process on the LC 180 CC machine.
“With this series of space-saving machines,” Yoders said, “vehicle manufacturers can develop a complete production line, in which all gearing components for a passenger vehicle transmission can be ground: planetary and sun gears, bore-type gears, as well as drive and pinion shafts.“
A Systematic Approach
EMAG LLC (Farmington Hills, MI) will be celebrating 20 years in the US during IMTS. The member of the EMAG Group is no stranger to a systematic approach to gear making. Its multiprocess machining line nicknamed the gear factory has been around for a while now. (For more details, please visit http://tinyurl.com/gearfactory.) In Chicago the company will display multiple machines from its new modular standard VL and VT product families. These offer a systematic approach that enables manufacturing process, with different operations offered on the same platform, allowing for easy interlinking and eliminating any great capital investment for automation.
The VL vertical pick-up lathe series is capable of machining a wide range of chucked components. Small gearwheels, planetary gears, sun gears, sliding sleeves, synchronizer rings or flanged components, for example, can be machined with great efficiency. The VL 2 machines workpieces with a maximum diameter of 4" (102 mm) and a length up to 6" (152 mm). Increasing in size, the VL 4, VL 6 and VL 8 offer a number of different turning and milling operations within the framework of a single closed-loop production process. Specially designed to handle large components, the largest, the VL 8, is well suited for commercial vehicle production, with the ability to handle workpieces up to 16" (406 mm) in diameter and 12" (305-mm) long.
The VT-Series for machining large quantities of shaft components employs the same modular concept. With four axes, a self-loading turret and integrated automation, the VT 2-4 machines shafts with a max diameter of 2.5" (63.5 mm) and 16" long. Spindle speeds of up to 6000 rpm achieve extremely short cycle times as the shaft is clamped vertically between work spindle and tailstock and machined from two sides. The vertical alignment of the workpiece ensures process integrity, where the unhindered chip flow prevents the build-up of chip nests in the machining area.
Looking at the Big Picture
David Goodfellow, president of Star SU LLC (Hoffman Estates, IL), said his customers also take a big-picture view of gear making: “Larger customers want a fully integrated supplier who can provide machine tool and cutting tool design, tryout, automation, reconditioning of tools and technical support of the full process.”
The company’s vice president of Sales–Cutting Tools, Tom Bell, delved into some of the details of these areas.
“Longer tool life, more parts per regrind,” he said, “are a constant topic from large OEMs, particularly in automotive. The advancement in substrate material—steels and carbide types—and coatings have impacted tool performances the greatest,” he said. “This ultimately gives end-users better performing and longer lasting tooling.”
Bell also noted that tool simulation to better predict cutting tool behavior has been of great benefit in gear making.
In addition, Bell said, the end users desire for quietness and “the goal to maximize power transfer from gearing have led to more sophisticated tolerances” even as “faster cycle times are required by gearmakers.”
Bell said Star SU’s focus at IMTS will be on advanced material for high performance hobbing, the G250 Vertical Gear Grinder, as well as its national channel partnership with Sandvik Coromant for gear milling tools.
In addition, Star SU, will be displaying its new larger portfolio based on its newly extended partnership with FFG Werke GmbH, a German machine tool manufacturer. The Star SU portfolio now also covers VDF Boehringer and Hessapp turning machines as well as Hüller Hille machining centers and Witzig & Frank multiway, multispindle machines. ME
—Executive Editor James D. Sawyer
To view the complete IMTS preview for this pavilion as a PDF, click here.
Published Date : 8/1/2014