This part wasn't machined. It wasn't stamped. It was "printed." (ProMetal)
Addressing the economical needs of the supply base. (Makino)
Vertical machines together for production ops. (Mazak)
Designed for stand-alone or zero-space cells. (Toyoda)
Twin pallets and a horizontal spindle. (Fadal)
Where accuracy meets the factory floor. (Zeiss)
One of the more meaningful themes at the IMTS came during a presentation given by Renishaw (in the U.S., Hoffman Estates, IL), a developer of all manner of things metrological*: "When times are tough, smart companies look to innovation to increase their efficiency and maximize every opportunity."
Innovation Meets Agility
And in many regards this sense of clever innovation was exhibited in varying degrees by some of the companies that were representing their wares at the show. On what is certainly a leading edge of this was being launched by ProMetal. In the interest of full disclosure, I must tell you that ProMetal president Rick Dove is (1) a former columnist for this magazine and (2) one of the founding architects of agile manufacturing. Consequently, I was (1) able to ask him brutally frank questions, outside the bounds that others who haven't known him for quite as long would be inclined to and (2) he is a man who is not likely to associate himself with run-of-the-mill products, which wouldn't be in keeping with his evangelism for all things agile.
ProMetal is a division of Extrude Hone Corp. (Irwin, PA). ProMetal provides a machine (or a service for those who'd rather forego machine ownership) to perform three-dimensional printing (3DP), a process that the company licenses from MIT. The "printing" in question is not like the ink on this page. Rather, it is one that replaces ink with powdered metal or ceramics and binders so that the output of the machine is actually physical parts that can measure, depending on the model of 3DP machine used, up to 1,000 x 500 x 250 mm in size (or be a series of smaller parts that fit within that envelope) and as great as 120 lb. in mass. The biggest machine is capable of producing 8,000 1-in3 parts in 48 hours. (It needs to be noted, however, that it is necessary to sinter the parts, which melts the binder, then to infiltrate the resulting porosity with a metal.) Like contemporary printing, the basis of the design is a data file; the machine uses a multiplicity of printing heads that actually resemble the type used in a desktop printer.
The beauty of this process, Dove explains, is that there is the ability to actually create mass customized parts as needed much more quickly than could be attained through traditional machining operations, to say nothing of the fact that the geometries that can be realized (e.g., cavities, undercuts) may be unmachinable. When asked about competition with laser-based processes, Dove suggests that while they tend to be limited to a single laser, the 3DP process can scale with an increase in the number of printing heads.
When asked about customers, Dove is comparatively tight-lipped, referencing in passing only that General Motors is doing something with the process as it relates to the lost-foam casting process—which isn't entirely surprising, given that GM engineers, people from MIT and folks from ProMetal worked on a four-year NIST-sponsored program on that very subject.
But this isn't just about the machines. Dove and his cohorts are creating what they're calling an "Agile Rapid Production Network." Dove defines this as a network of companies all of which are interested in doing things rapidly. While other rapid prototyping firms have long had service bureaus, Dove sees this network as being one whereby they're able to provide customers with finished parts even if the 3DP process is but one of many processes involved.
Of course, not all firms are interested in something like 3DP, especially if they have production volumes and tight schedules after a longer leadtime. Which brings us to Liberty Precision Industries (Rochester, NY) and its president, Douglas K. Woods. What is interesting about what Woods has in mind is that while he admits that Liberty is a special machine builder and systems integrator that, of course, has products (e.g., they're big on dual- and quad-spindle machines), he goes on to say that most machine builders are interested in fitting a particular part to a machine while at Liberty the approach is to start with the part (some of the types of parts that they're well-versed in include steering knuckles, control arms, manifolds, and other items with features including angular holes and close tolerances that are made in annual volumes of 250,000 units or more), and then trying to figure out the machine or system that is best suited to process it. He often uses the term "morph," as in, "We don't know what our machines will morph into next year." That's because he doesn't know what kinds of parts they'll be producing.
Liberty has created something of a network itself to supply cells and systems. In February, 2002, it signed a partnership agreement with German builder Schwabische Werkzeugmaschinen GmbH, which specializes in the aforementioned dual- and quad-spindle machining centers, both horizontals and verticals (e.g., the twin-spindle vertical BAS03-22, which is fitted with 20-hp, 17,500-rpm spindles, twin trunnion tables for a 3.5-second workpiece change, and a work envelope of 300 x 400 x 400 mm). And it is working to network capabilities in other parts of the world, as well.
One of the innovative strategies that Woods and his colleagues use to create custom cells and systems is to use standard components wherever possible, thereby reducing both cost and time to build. While there are certainly an array of competitors to contend with, Woods describes the management of the company as people who are "young, aggressive, and want to do something different." And given that the company has been around since 1922, it's fair to say that they're experienced, too.
Alliance & Action
Before leaving the subject of companies getting together, it is worth noting that Roger Cope, vice president, Business Development, Lamb Technicon Machining Systems (Warren, MI), says that Lamb and Yasunaga Corp. of Japan have created a strategic alliance. Lamb is well known in North America for its head, block and case manufacturing systems. Yasunaga is known in Japan for automotive parts and machine tools and systems. Cope explains that by working with the Japanese company Lamb will be in a position to provide systems, particularly to the "transplant" automotive companies that will be more competitive from a cost and technology point of view. Speaking of technology: Lamb has developed a horizontal machining center, that can be used as a stand-alone or as a transfer machine module, for milling and drilling aluminum and magnesium that has what it calls a "hybrid kinematic" design. Which means that using standard AC servo motors and ballscrews it can deliver acceleration rates of 1.5 g in X and Y and 2.0 g in Z, a rapid traverse rate of 80 m/min, and positioning accuracy of +/-0.005 mm. It is equipped with a 16,000-rpm, 20-kW spindle (HSK 63A taper).
Linear motors had what seemed to be a slight boom a few years back, and then have, by an large, receeded from view. But they may become much more in evidence thanks to an undertaking at Deckel Maho Gildemeister (DMG; Schaumberg, IL), whose chief executive, Dr. Rüdger Kapitza, is essentially mandating that when company engineers develop new machines, they implement linear drives wherever appropriate. An example is the DMC V linear line of vertical machining centers. Each of these machines (there are three sizes, with X, Y, Z travels of 25.2 x 23.6 x 19.7 in.; 40.9 x 23.6 x 19.7 in.; 56.7 x 23.6 x 19.7 in.) features a linear motor in the X-axis, which results in the ability to achieve rapid traverses of 2,755 ipm. Similarly, the X-axis drives of the CTX 320/420 universal lathes are fitted with linear drives (the swing diameter and longitudinal travel for the CTX 320 are 15.7 in. and 17.7 in.; the numbers for the CTX 420 are 26.8 in. and 25 in.). Kaptiza is guaranteeing that the users of DMG equipment with linear drives will achieve a productivity increase of 10%, thanks to the rapid positioning capabilities that they provide.
Cost is a concern that is an abiding one throughout the industry. Some companies have specifically focused on developing flexible machines for the auto industry that are in keeping with this overall sense of fiscal responsibility. Among them is Makino (Mason, OH), which has long been known for the horizontal machining-center based systems that are used in powertrain and brake system manufacturing operations. Heretofore it has offered machines like the A55E (400-mm pallet; 14,000-rpm spindle) and the A77E (500-mm pallet; 12,000 rpm, 50-taper spindle). However, because these machines have tended to be used by OEMs and tier-one suppliers, the company has developed a series of machines with an "a" designation.
So there are machines like the a51 horizontal machining center, with a 400-mm pallet and a 12,000-rpm spindle and the a71, with a 500-mm pallet and a 10,000-rpm, 50-taper spindle. The objective in developing this line of machines was to provide performance while reducing the price vis-à-vis not only its own line of machines, but also those of the competition.
Similarly, Mazak Corp. (Florence, KY) has engineered machinery that is well suited for applications in high-volume production applications—where lean manufacturing and the necessity of flexibility are taken into account—but here the spindle orientation is vertical. Included is the IVS 200—with the IVS designating "inverted vertical spindle," which means, in part, that the spindle is used not only to rotate the part, but to provide material handling action, as well. This two-axis CNC turning machine's spindle has an integrated motor (eliminating gears and belts); it accelerates to 5,000 rpm in just 1.8 seconds and it provides a maximum torque of 147.5-lb.-ft. The rapid traverse in X is 4,330.7 ipm; it is 2,362.2 ipm in Z. The turret rotation is quick, too: 0.17-sec/step. The machine is designed with a small footprint with easy accessibility for all maintenance points. As a result, the machines can be lined up for higher-volume operations.
A horizontal spindle CNC machine that's designed to operate either as a stand alone or configured in a line in an exceedingly compact manner is the TOP J from Toyoda Machinery USA (Arlington Heights, IL).
First of all, the TOP J has a compact footprint: just 39 x 106 in. But they've gone far beyond just that: the machine is available in both left- and right-hand configurations: this means that you can place two machines next to one another so that there is zero dead space between them. Expensive floor space considerations are, consequently, not as big an issue as they otherwise might be.
The Long Run
Another company that's looking toward providing equipment that can work in automotive-type environments, where 24/7 is not an unusual cycle demand, is Mori Seiki (Irving, TX), which is offering a new horizontal machining center, the NH5000. Toward that end, there is one feature of the machine that is emphasized—and which is typically not talked about when promoting a new machine, although it is a key consideration once a machine is in action: it has been designed with a triple-action chip trough (given that it has a 30-hp peak direct-drive spindle that goes from 0 to 14,000 rpm in 1.4 seconds and the X, Y, Z rapids are 1,968.5 ipm, there are clearly plenty of chips that can be generated in comparatively short order). The trough, incidentally, includes a central hinge conveyor flanked by spiral conveyors. The NH5000 is a 500-mm pallet machine (a.k.a., 19.7-in.2); pallets can handle up to 1,102-lb. payloads. In keeping with the whole notion of lean operations, the machine was designed with features that contribute to a minimal mean time to repair (MTTR), such as centralized and organized features (e.g., lubricant pump; air equipment control; cable wiring) so that repair people can get right at them.
Fadal Machining Centers (Chatsworth, CA) has long been known for its line of vertical machining centers. Yet the company has found that when its customers started looking for horizontal spindle machines to bump up their production levels, they began to look at other vendors. So, not to lose customers, they've developed the HMC 400, a 400-mm twin pallet machine. It features 20 x 24 x 20-in. travels, a 10,000-rpm spindle, a Siemens SINUMERIK 810 D digital control, a 40-pocket toolchanger that provides 1.2-second tool-to-tool time. And it is said to be engineered for a 24/7-duty cycle. The pricing is expected to be in the $170,000 range.
Like the Wind
Machining is predicated on having something to do the cutting, of course. Sandvik Coromant (Fair Lawn, NJ) has developed a high-speed face mill, the CoroMill Century, that is really all about getting it done on aluminum, as it can be used with either polycrystalline diamond (PCD) or uncoated carbide inserts, and run, depending on mill diameter, at up to 40,000 rpm (e.g., in this case, a 40-mm diameter mill). It is worth noting the PCD tools are what the mill has really been developed to work with. Key applications are light roughing, finishing, and superfinishing; surface finishes on the order to 10µRa have been obtained. The mills are available in diameters from 40 to 200 mm. There are a couple of key features to note. For one thing, when machining at high speeds, getting the inserts appropriately seated in the pocket is essential. So to assure that, there are serrations on the seats and on the back of the insert. Another important aspect is making sure that chips are out of the way, fast. So the CoroMill Century is designed (1) with through-the-body fluid and (2) that there is a cyclone effect set up such that as the mill rotates faster, the more effective evacuation becomes.
For those who are looking for high-production or large-batch turning of steel, Carboloy (Warren, MI) has developed a new coated cemented carbide, designated TP1000. The substrate is cobalt-enriched so that the interior is hard and the surface region is tough. Which means that it can endure high cutting speeds. Don Graham, the company's manager of Turning Programs, Don Graham, is quoted as saying, "Trends toward increased productivity, dry machining, and difficult-to-machine materials demand higher wear resistance, deformation resistance, and toughness all combined into one grade." The insert is available in geometries for roughing, medium-roughing and finishing.
Of course, there is the requirement for grinding, and one of the more interesting developments in the volume production arena for shafts—as in camshafts, crankshafts, and gear shafts—is available from United Grinding (Miamisburg, OH). It's the Schaudt Mikrosa BWF Zeus S, which provides 300 mm between centers and a center height of 175 mm. The machine is designed for use with CBN wheels (galvanic- and ceramic-bond types); cutting speeds of 120 m/sec. can be attained. The machine has a sliding Z-axis that employs a digital ballscrew drive; the X-axis has hydrostatic guideways. This adds up to precise machining and repeatability. One of the challenges of crank grinding relates to clamping the workpiece in the chuck so that the crank pin can be cylindrically ground. The Zeus S machine ameliorates the difficulty by having a central clamping chuck; the machine control (a Siemens Sinumerik 840D is used) actually makes the adjustments necessary to cylindrical and eccentric grinding, thereby greatly simplifying the process.
After all is said and done, parts really aren't done until there is some assurance of their quality. Which leads to a new bridge-type coordinate measuring machine (CMM) from Carl Zeiss IMT (Minneapolis), the CenterMax, which is described as a "production measuring center." Yes, this is a shop-floor CMM, one that's said to be capable of sitting right next to a machining center or the like. Certainly, there is an active vibration package that keeps things stable from that perspective. One of the issues related to CMMs in the general environment is that temperature can have an effect on measurement accuracy. So Zeiss engineers have really gotten to the fundamentals with this machine, by developing a patented temperature-resistant frame fabricated with invar (a steel alloy). It has thermal damping properties; the machine is said to be guaranteed to provide results in a range of 59 to 95F. The accuracy of the machine is u1 = 1.3 + L/350; the measuring volume is 35 x 47 x 27 in. The CMM can be configured with a pallet carrier frame, a granite plate, or a rotary table integrated into the machine bed, which means that part loading is facilitated.