Automated selection and assembly of sets of blades for jet engine compressors and turbines

摘要

Aircraft engines need to pass regular maintenance intervals, which go along with a complete disassembly, part inspection (with necessary repair or replacement) and finally reassembly. Especially the manual composition and assembly of blades are time-consuming processes. Increasing air traffic and growing pressure on costs in aviation MRO, demand more efficient approaches. This paper introduces an automated approach for increasing efficiency in selection and assembly of sets of blades for jet engines. Chapter 1 gives a short overview on different designs for compressor and turbine stages. Additionally, the process of adjusting and mounting a set of blades into a circumferential groove is described. Furthermore, a potential for an automated assembly process is determined. Chapter 2 gives an overview of the overall concept, including robotic blade handling, measuring of blades, balancing a set of blades and gap measurement. Chapter 3 focusses on the two measuring tasks. For measuring the width of the blades, optical and tactile approaches are compared. Image processing and laser triangulation are compared to current use of feeler gauges for the gap measurement. In chapter 4 a force-guided assembly strategy, using a force-torque-sensor is presented. Chapter 5 concludes with a brief overview of the planned future work.