New lifting methods for gas turbine combustors and casings
In order to compete successfully with other manufacturers, the European gas turbine industry is continually seeking to improve safety and comply with future environmental legislation. Having anticipated the future legislation requirements such the Committee on Aviation Environmental Protection (CAEP3), this 48-month RTD project investigated a change in design styles with the increased use of high stress concentration features. The aim of the project was to produce verified lifting methodology for the design and in-service support of combustor components like angled effusion cooling holes; however this requires a thorough understanding of material behaviour. Hence the primary emphasis focused on the development of three types of material behaviour models, and how they could be implemented into Finite Element (FE) programmes for component design. Based on Thermo-Mechanical Fatigue (TMF), isothermal test results and specimens that contain representative component features; two materials known as C263 and Haynes 230 were studied. Their material behaviour was subjected to stabilised component stress predictions, the prediction of component life at design stage and crack growth models to enable safe inspection intervals. The obtained results produced various complementary stabilised component stress and strain predictions, and also demonstrated very good lifting correlations under different conditions for isothermal specimens. In addition, the crack propagation modelling proved to be successful in predicting the behaviour of plain and featured isothermal specimens. Overall, most of the programmes within this project made significant progress for the development and verification of lifting methods for both combustors and casings. Work will continue to assess components once they have been run to the point of failure, whilst additional programmes will focus on lifting methods that will not increase component development timescales.
