DNC system adds flexibility and functionality at automaker's machine shop

Modern Machine Shop, June, 1993

And now there's expandability. Whereas the old environment was limited at linking six machines, the new system's growth is unlimited. All of the shop's machine tools are now linked. To handle future growth, all that is needed is to add another communications hub.

There's virtually unlimited expandability for workstations on the network, too. That's a very important consideration because while Powertrain is installing 47 workstations now, many more will be added by mid-year to handle a new engine program. This addition will increase production another 50 percent. All workstations, present and future, will be connected via the new DNC network. The interconnect ability between all the workstations and machine controllers will help Powertrain speed products faster to market.

The majority of workstations presently on the network, about 40, are used by designers to design parts on another floor of the same building. Once designers finish their part designs, they notify the machine shop that the part is ready for cutter path development. A CAM operator is assigned the part, who retrieves the part through remote log-in. He develops the cutter path and sends it to the NC machine.

In addition to unlimited expandability, memory has dramatically increased. Whereas the old system had a total of 20 megabytes for the entire shop, now each new workstation has 1.3 gigabits of disk drive memory, that's 80 or more times more than the previous environment. Plus, each personal computer has a 40-megabyte hard drive on the personal computer, enabling machine tool operators to store all of their cutter path programs right at the machine, retrievable at a moment's notice.

"Once a cutter path program is created, it can now be edited at the machine," says Mr. Schlee. "That's a 25 percent time-saving improvement. Before, the machine operator would shut down the machine, go to the computer room, log onto the system, make his edits, recompile the program, generate the tape program, download it to the machine, and test it again. This was an iterative process until he got it right. Now, with EDS-DNC, the operator verifies the cutter path right on the screen and downloads it there. If minor editing is required, it's performed at the personal computer while the machine is running."

Another time saver for the machine operator is the availability of graphics at the personal computer at the machine. On-screen graphics eliminate having part prints all over the shop. Graphics of fixtures, clamps, and other engine parts are used by operators to setup parts off-line for subsequent machining operations.

A significant factor contributing to the software's success is that it is constantly being upgraded. The software's functional features--expandability, flexibility, security, and so on--are continually enhanced by an EDS-DNC Users' Group. The group consists of purchasers of the DNC software. The users group meets quarterly to discuss and prioritize suggested enhancements. The original developers of the software from EDS' Ohio Technical Support Center in Dayton, Ohio, attend to provide insights on what they believe good and what is not in the best interests of the software and existing users. A vote on proposed enhancements follows. Approved enhancements are incorporated into the next release and made available to all users.