Triumph Aerostructures and the need for flexible post-processing


Triumph Aerostructures – Vought Aircraft Division, a subsidiary of Triumph Group, Inc., is a leading global manufacturer of aerostructures for commercial, military and business jet aircraft. The company has full fabrication capabilities and available products include fuselages, wings, empennages, nacelles and helicopter cabins. The company’s customer base consists of the world’s leading aerospace OEMs. Triumph Aerostructures – Vought Aircraft Division employs about 6,000 people in six U.S. locations.

One of the company sites, located in Nashville, TN, produces individual parts and sub assemblies for Airbus, Gulfstream, Cessna, and Lockheed Martin. With approximately 900 employees spread over two million square feet of work space, the Nashville site has 10 large CNC gantry mills, nine large assembly riveters, and a variety of smaller CNC equipment. In the machining area, there are more than 35 CNC spindles making chips. “The Nashville facility focuses on parts that are ‘long and large.’ Most everything we do is longer than 30feet,” said Lead CNC Programmer Bill Gwinn. Those ‘long and large’ parts start out as massive engineering models, many of which reside in legacy CATIA-V4 CAD/CAM data files.

Using ICAM’s Post-Processing software, Triumph has been able to convert CAD/CAM engineering data files into Computer Numerical Control (CNC) code, quickly and virtually error free. As of 2007, many parts are being developed, or imported through a newer CATIA-V5 system. Using a two step process, CNC programmers can extract the graphic engineering data (from either system) into APTSOURCE (APT) files, which are then fed into the ICAM Post-Processing software. ICAM converts the APT information into customizable code for each CNC machine.

Current ICAM Posts
Since 2007, three new Post-Processors have been developed for three different CNC machines. The first two are for Handtmann 5-axis mills; one with a single head configuration, and the second having a twin-head gantry setup. The most recent Post was developed for an older Cincinnati 5-axis Gantry mill that was ‘retrofit’ with a new Siemens 840D Control, the same control used on both Handtmann mills.

After processing the APT files through ICAM, the final output (CNC code) instructs the CNC machines to mill Aluminum billets into precision aircraft components. Typically, these large complex parts have machine times measured in days, rather than hours & minutes; and that’s with three shifts of machining. Parts this big require large programs; in many cases, multiple large programs. According to Gwinn, that’s where ICAM has paid for itself. The processing time for these programs takes about half the time as the old Post-Processor.

While ICAM has proved itself as a valuable tool, Gwinn says that his time training at ICAM was “invaluable.” The two training sessions spent helped us go beyond just using ICAM. Triumph also has an ICAM developer’s license, and used it to build the first two Posts. This also allows users the flexibility to modify any post as needed.

In the case of the Cincinnati post, Triumph was faced with a unique situation where time was a key factor in building the new post for this upgrade. Fortunately ICAM was able to work with Gwinn and help develop and finalize the post in just a few weeks. “Our goal was to use the existing APT files, over 70 of them, and run them through a new ICAM Post to achieve the same tool path” said Gwinn. Since the Control upgrade would use a different tool path method; Tool-Tip vs. the previous Knuckle-Driven method, all programs required reprocessing. “ICAM did an excellent job collaborating with us to develop the Post, in order to give us an error free CNC tool path; especially with little to no changes in the original APT files.”

Future plans for the Nashville site include using ICAM Post-Processors on all new work and any machine-control upgrades.