Factory Fundamentals
The company sets up multiple jobs in advance for storage in the container of the Fastems FPM
150 per cent, the new machine completed each part in 3 minutes and 45 seconds – 50 per cent less time than the previous machine. Additionally, the ability to run the parts at the higher feeds and speeds recommended for that particular combination of tool and material improved surface finish quality by nearly 50 per cent. Overall cleaner cutting eliminated most of the hand deburring, reducing total cycle time for that secondary operation from more than seven minutes to less than one minute per part. With the previous machine, the shop had to reduce the feed rate to meet tolerances on parts mounted at the top of the tombstone fixture or farthest away from the pallet table. “The cutter was working far enough out from the bearing surface to act like a long lever,” Landau explains. “We had been getting too much deflection between the pallet table and the coupling. On the Doosan, running at a 50 per cent faster feed rate, there was still no deflection.” These gains were particularly notable because the part’s surface included a 3D radius that blends into a straight wall, he says. This required simultaneous X-, Yand Z-axes movements. Much of the cycle time savings were achieved during these moves, which involved toolpath calculations that many CNCs could not handle. In that scenario, he says, the CNC typically suppresses the programmed feed rate. That was a non-issue for the Fanuc CNC and its 200-block look-ahead capability. In addition to improving productivity and part quality, the cell has redefined the company’s notion of what setups should entail, Vise says. Running virtually 24/7 has reduced interruptions and downtime previously associated with change-overs. Landau adds that production control is easier and more effectively executed. “We have eliminated variation at many points in the production chain. We do not see the spikes in production like we used to. We see higher, straighter-line charts, and that is a very good thing.” he concludes
June 2011 - MODERN MACHINE TOOLS 107