Heller Looks To Pump Up the Energy
By James D. Sawyer
Motorized vehicles were frequently mentioned during Heller WerkTage (literally Working Days) 2014 held at the company's headquarters in Nürtingen, Germany. That’s not surprising for a number of reasons. For one Nürtingen is not far from Stuttgart, where Karl Benz invented what is considered to be the first automobile. Benz was granted a patent for his invention in 1886. Eight years later the company now known as Gebr. Heller Maschinenfabrik GmbH was founded in Nürtingen.
In the intervening 120 years both companies have grown and most often prospered. That’s illustrated by a little-known fact: since 2004 about 80% of the machining for heavy truck engines has been done on Heller machines. (You probably already know about Benz, his colleague Daimler and the Mercedes vehicles that wear the three-pointed star.)
While automotive and aerospace are the key industries served by Heller, the company is beginning to increase its focus on the energy industry. WerkTage 2014 saw 15 energy customers from the US in attendance, according to Vince Trampus, Vice President Sales & Proposals of Heller Machine Tools LP (Troy, MI). Given that Heller has added larger machines to its C Series, the large workpieces often required by the oil & gas industry are well within its reach. (In addition, Heller sells a good number of machines to the power generation industry where the drives and generators are similar to equipment found in autos and airplanes.)
Among these larger machines is the CP 8000, which was on display in Nürtingen. It is a combined mill/turn five-axis machine that has a work envelope of 1250 x 1200 x 1400 mm. It can accommodate workpiece diameters of as much as 1250mm with pallet loads up to 2000 kg. This is topped by the new CP 10000, with a work area of 1600 x 1400 x 1600 mm that can accommodate workpiece diameters of 1400 mm and pallet loads of 4000 kg.
Six other machines were on display in the WerkTage 2014 showroom, beginning with the H 2000. This is a bread-and-butter four-axis machine that both mills and drills and can be ordered with an optional fifth axis. (This also can be added to the H 2000 at any time after the machine has been delivered.)
The five other machines operating on the showroom floor were all five-axis multifunction units: an H 4500, H 6000, FP 4000, FT 4000 and a CP 4000.
However, the machine that perhaps best grabbed the attention of attendees was one in the event's Technology Center demonstrating a very nontraditional machining process: cylinder-bore-coating (CBC) machining of an engine block.
To date, most lightweight automotive engine blocks use cylinder liners in order to provide the surface finish needed to optimize fuel economy and lower emissions. CBC is a lighter-weight cost-effective alternative that incorporates twin-wire arc spraying. Heller in cooperation with Daimler and other partners is working to integrate the process into volume engine production.
While the demonstration in Nürtingen did not include all the steps of the process, in full operation CBC machining includes premachining, fine boring, coating, finish machining and finish honing of the coated cylinder bore on a Heller MC20 four-axis machining center. Total cycle time, including part load/unload, for an eight-cylinder engine is five–six minutes. The engine blocks may be direct-loaded into the machining center or mounted on a swiveling exchanger.
A key contribution of Heller to the process is to fine-bore the arc-sprayed cylinder coating to impart a final finish. Previously this was accomplished with honing, but the Heller fine boring process takes about half the time and assures a much more consistent finish and form to the cylinder due to the machining center spindle axial orientation to the bore. Tooling cost is also much lower compared to honing.
For a more in-depth look at CBC machining look here.
A final display, this one in the Marketplace Assembly area, that indicates how Heller is looking to the future was that of August Wenzler Maschinenbau (Spaichingen, Germany). Heller realized some time ago that autos would have to become lighter in order to become cleaner and more efficient. In partnership with Heller, Wenzler has been working since 2009 designing and building machines for machining complex aluminum structural components.
What they have come up with is essentially two five-axis machines integrated in one unit. The machine is capable of cutting dry or with minimum cooling fluid. The arrangement is said to be very cost effective. Currently it is aimed at premium automakers such as Jaguar and Land Rover, but as more and more car companies reduce the weight of their vehicles these aluminum structural components will become much more common—as will the machines needed to make them.
Published Date : 5/30/2014