Method for Assessment of the Residual Life of Turbine Disks

摘要

A method for assessment the durability of turbine disks at the stages of damage removing and development subject to structural and technological changes is developed on the basis of the nonlinear mechanics of deformation and fracture. The proposed method includes numerical analysis of the stress-deformed condition of disks in the initial and damaged states, determination of stress and strain fields in the zones of cutting of the damaged material volume, and calculation of low-cycle fatigue and the duration of crack growth from initial to critical sizes. The theory of the developed method is the concept of a fracture process zone. The method is used for comparative evaluation of stress-deformed conditions and durability parameters for options of changing the geometry of a steam turbine disk by removing the damaged material around slot fillet of key.