Improved Process Controls for the Laser Drilling of Small Holes (1001-938)

Triton Systems, Inc., in partnership with the National Aerospace Leadership Initiative (NALI) funded Connecticut Center for Advanced Technology (CCAT), is developing the concurrent use of multiple sensor types and methods to collect laser drilling process data. This data is then processed by a specially designed integrated control system to generate a real-time, bi-modal breakthrough detection (BBTD) device to monitor and control the laser cooling hole drilling process for gas turbine components. The monitoring and control system will collect data from multi-mode sensors related to the laser pulse interaction with the turbine component material and resulting plasma plume. Current single mode breakthrough detection methods, which predominantly use broad band spectral sensing devices, are not considered sufficiently effective or reliable. The current alternatives are fixed pulse number per hole protocols that result in component airflow variation of up to +/- 10%. This leads to unnecessarily high numbers of defective parts from over- and under-drilling. It is estimated this multi-mode concept could reduce airflow variation from +/- 10% as currently experienced to +/- 2%-- a fivefold reduction. Tighter control of airflow results in longer turbine component life, reduced overall production cycle times and costs, and an increase in gas turbine efficiencies.