Highly Accurate Automated 3D Measuring and Data Conditioning for Turbine and Compressor Blades

Abstract

The measurement of compressor or turbine blades is very interesting for quality control and inspection checks. Especially for mechanical wear valuation it is important to inspect the whole geometry of a blade with main focus on the airfoil. This 3D measurement task, which involves many identical components, and high accuracy, as well as high point density in the airfoil edge regions, demands detailed planning of the appropriate 3D-measuring machine, measurement planning, reproducibility as well as analysis and provision of measuring values for the user. Preliminary investigations were carried out to select an appropriate measuring method providing both a complete geometric and as automatic as possible acquisition of blade geometries. Another constraint was that the technique had to make efficient use of time and be accurate. A data processing routine using software developed at TU Dresden is used for automated analysis and provision of measuring values for the user. The approach to linking automated complete 3D data acquisition by means of strip projection with automated analysis of measuring data opens up the option of using it as an efficient 3D-measuring machine for high accuracy requirements and higher quantities. The method shown can be transferred to other objects that need to be scanned in larger quantities.