CompositesWorld
Issue link: https://cw.epubxp.com/i/630867
FEBRUARY 2016 6 CompositesWorld OUT OF AUTOCLAVE SUPPLEMENT types of parts could also potentially be designed for OOA manufacturing. Typical VBO prepreg panels, such as the trailing edge Upper Panel 12 (in Fig. 1, p. 4) were layed up under clean- room conditions on the mold tool, then vacuum bagged and moved to the oven for cure. Fig. 2 shows Upper Panel 12 in the oven (note that thermocouples are installed on the underside of the mold tool). During cure, cycle times and temperatures for the OOA MTM44-1 system are comparable to those for conventional 350°F/177°C autoclave-cure materials but the cure cycle is without the complexities of control of positive pressure. Full vacuum only is maintained throughout the cycle. Following cure, the upper panel was vacuum-secured to a machining fxture within a CMS (Caledonia, MI, US) machine for fnal machining and drilling. Tat fxture also is the fnal buy-of fxture for the panels to prove that the product is correct to model. Fully machined upper panels, drilled and countersunk, require a pin check and deburring before transport to the NDT facility, where they are reviewed using ultra- sonics for possible faults and defects during layup. After successful completion of this process, the panels are moved to paint, prior to assembly. Panel quality is comparable with conventional autoclave-cured honeycomb sandwich panels, with porosity levels that reportedly meet all customer requirements. "It's all about cost and rate nowadays," explains John Savage, technical authority composites. "OOA [prepreg] is well positioned to tackle both these requirements, while it also provides a simpler produc- tion system compared to in-autoclave usage for certain applications." GE Hamble has proven the throughput and cost principles of this process in its high-performance automotive programs. As the new A350 XWB has become the stage for its production debut in an aero- space environment, validation of the advantages is anticipated when stable and mature production has been reached. Te current package requires GE to deliver about 14,000 composite parts per annum, which will rise with the projected demand for more aircraft. To meet the projected demand, GE, as part of a fve-year, US$50 million-plus investment at the Hamble site, has developed a new 9000m 2 composites production facility. Both in-autoclave and OOA operations will be housed in the new center. Te new facility reportedly will incorporate the very latest factory automation technology to improve the efciency of the long established hand lay-up manu- facturing technique: Tool movement and tracking will use advanced technology, driven through the Manu- facturing Execution System (MES). Layup tools and product will be tracked through the factory, using wireless technology. Control systems have been integrated into the layup stations to automate the services and the projection lasers, both of which are automatically driven through the MES. Automation and advanced material handling is a theme carried throughout the new composite facility, in line with the principles of Industry 4.0. Building on this success in OOA technology, GE Aviation is focusing R&D; eforts on creation of other materials and manufacturing processes, both in- and out-of-autoclave, together with optimizing composite design methods through a number of UK government and EU-funded research and technology programs. GE Aviation Hamble is set for a busy future. Read this article online | short.compositesworld.com/VBOA350 FIG. 2 Bagged and ready for oven cure The vacuum bagged Upper Panel 12 in oven, ready for cure, with thermocouples (mounted on the underside of the toolface) wired for cure- temperature control. Source | GE Aviation