Life Assessment for Creep and Fatigue of Steam Turbine Blisk

Arun kumar H D, Dr. S G Gopala Krishna

Blisk, Integrated bladed rotor, Thermal gradient, Creep, Fatigue.

Steam Turbine Rotors are one of the key sectors among rotating machinery heavy engineering components. These machines operate at a constant speed at high pressure and high thermal gradients at the initial stages. One of the main factors concerning the mechanical integrity of these rotors is the interface between the blade and the disk. The contact region between the blade and the disk happens to be the most critical zone in the blade rotor. In order to manage high stress gradients at the blade root region, the rim of the disk is made heavier. The mass of rim of the High Pressure stage collectively makes the design bulky. Apart from the design being bulky, the chances of the contact region leading to crack initiation due to high thermal gradient and enormous centrifugal force over a period of time can lead to fatigue creep interactions reducing the life of the disk. In the present work, one small effort is made to integrate the blade and the disk to form Integrated Blade Rotor commonly known as “BLISK” for the first stage blades. And reduce the Mass of the rotor by scooping the uniform disk.

10.22161/ijaers.3.8.6