In a variety of industries there is a growing need to manufacture high quality carbon fibre epoxy matrix composite structures at greater production rates and lower costs than has historically been the case. This has developed into a desire for the automation of the manufacture of components, and in particular the lay-up phase, with Automated Tape Laying (ATL) and Fibre Placement (AFP) the most popular choices. When used for large primary structures there are such potential gains to be had that both techniques have seen rapid implementation into manufacturing environments. But significant concerns remain and these have limited their wider adoption into secondary structure manufacturing, where manual forming of woven broadgoods is dominant. As a result the manufacture of secondary structures is generally explored for costs reduction through drape simulation and lower cost materials. Improvements in lay-up quality and yield are possible, but the effect of this approach on productivity and build costs has perhaps been under explored. This paper investigates this by reviewing the manufacture of a complex geometry representative of a fixed trailing edge panel, identifying the current forming philosophy and then applying novel drape simulation tools to improve on that forming route to facilitate productivity increases. This was possible by the development of unambiguous forming instruction sets, that when combined with some preforming solutions further increased the productivity and cost reduction potential. The low cost manual forming was compared to an in-house AFP productivity assessment, and it was found that the rates were comparable on an hourly deposition rate, but when assessed in terms of other metrics manual forming could still remain the most suitable manufacturing route. The work has shown that for complex structures manual forming with well developed drape solutions can still be the most low cost and productive process.
PresenterCarwyn Ward, Univ. of Bristol