The turbine rotor is composed of turbine rotor blade (rotor blade), turbine disk, turbine shaft, connecting parts between disks and seals, etc. Its main function is to convert kinetic energy and thermal energy of high temperature and high pressure gas at the outlet of the combustion chamber into mechanical work, which is used to drive rotating parts such as compressors, fans (or generators).
As a power component of high-speed rotation in high temperature air flow, turbine rotor needs to withstand high temperature load, aerodynamic load, centrifugal load and thermal stress, so its thermal strength, mechanical strength and reliability have harsh requirements.
The turbine rotor is made of high-strength superalloy, and a large number of cooling structures and thermal barrier coating materials are arranged on the blade.
The connection between disc and shaft, disc and disc, rotor blade and wheel on turbine rotor is very important. In multi-stage turbines, the rotor adopts disc and drum hybrid connection structure.
The connection between the disc and the shaft can be divided into non-removable disc shaft connections (such as radial pin connections, welding, forging integral parts, etc.) and removable disc shaft connections (such as long bolts, short bolts, sleeve teeth, etc.).
Disk shaft connection needs to have sufficient strength and stiffness, and can not weaken the strength of the wheel and shaft, in order to be able to reliably transfer a variety of loads, the disk and shaft should be reliably centered when working, so as not to destroy the balance of the rotor, and the connection should have high thermal resistance to reduce the heat transfer from the disk to the shaft.
Disk-to-disk connection is divided into non-detachable disk-to-disk connection and detachable disk-to-disk connection, among which the non-detachable disk-to-disk connection is mainly used for turbine rotors with fewer series.
The connection between the rotor blade and the wheel is mostly fixed by the longitudinal tree tenon, which requires the joint of the tenon to expand freely after being heated to reduce the thermal stress, and requires the heat transfer of the tenon to be good, so that the heat on the blade is easily transmitted to the wheel.
