Design Study of a Wing Rudder : Exploring the Possibility to Implement Additive Manufacturing

Sammanfattning: Subtractive manufacturing are the most common methods in the aerospace industry to manufacture components. In these parts the buy to fly ratio is low and it needs accurate strengths analyses to static and dynamic loads especially were the different parts relate to each other with fasteners in the assembly work. Additive manufacturing has now been developed to be of such quality that the aerospace industry see the potential to use the technology in their production of parts. It has been possible to make them lighter, stronger and reduce the total amount of parts in an assembly. This mean probably some changes to the stakeholders in the process of their product development. Engineers who are working on the products will need to face the design aspects and restrictions with AM to choose the right component/sub-assemblies to convert to AM parts. This thesis will address the possibility to redesign a wing rudder and to get some knowledge about the engineer’s point of view of AM and how it may affect them. Today there are several aerospace industries adopting AM and get airworthy components to less critical parts as brackets but also parts in the engines as the fuel nozzle in an Airbus (Trimble, 2016). For larger parts, there have also been studies to use AM for example internal galley partition but the result is it will take too long time to print by todays machines. There are several different methods for AM and Powder Bed System is popular in the aerospace industry according to its geometrical correctness to the CAD model (Dordlofva, Lindwall, & Törlind, 2016). Commercial aircrafts industry starts to get harder regulations for their emissions to get lighter planes and less air resistance. AM open up the possibilities to meet these requirements by producing parts which was impossible to produce before. The design process for AM design today are not fully known yet, which leave a lot to imagination. There are general design rules on how to design for AM build but it does not necessary mean the part will be correctly built. There are several cost driven aspects with AM, the most expensive part is the print time but there are different aspects to. For example, CNC machining may be needed after the AM build and add cost for subtractive manufacturing. Interviews with engineer’s groups have been made to conduct their thoughts and knowledge of AM and how it may affect their work. Some uncertainties were mentioned and it was most focused on the process and the reliability of the finished part. The engineers think the design process will be almost the same and only change boundary conditions. To get ideas, a workshop was made with some design guidelines for development of different designs on the wing rudder and to bring positive and negative aspects to the design. An overall cost calculation was made for a few parts and the result shows that it is hard to compete with the design of the wing rudder today. The most important aspects for a success of AM is the print speed, qualified manufacturing processes and CAD software support for the engineers.