Non-contact Type On-machine Measurement System for Turbine Blade

In turbine blade machining from a near net shape (e.g., forged workpiece), it is difficult to use a touch trigger probe for measuring the mounting angle of the workpiece due to its uncertain free-form surface. Therefore, non-contact measurement is required to determine the setup condition of the workpiece. Recently a high-performance laser displacement sensor has been able to measure glossy metal surfaces because of the progress in its sensing device. Using such a high-performance sensor, the non-contact type on-machine measurement system has been developed. It was installed on the multi-functional machine tool to determine validity of the system. This system measured the turbine blade cross-section to compare with CAD data and the measurement data by coordinate measuring machine (CMM). As a result, validity of this system for measuring a turbine blade was proved. We have proposed some application using this measurement system. The application enables optimal machining of a turbine blade from a near net shape at an appropriate phase. This contributes to minimizing the size of expensive material and the machining time.