Laboratory Study of a Steam Turbine Rotor Weld Repair

The repair consisted of severing the rotor between the 12th and 13th stages and welding a new forging, replacing the 9th and 12th stages, to the remaining original rotor. A test rotor was prepared from the scrapped rotor section using procedures similar to the actual rotor repair. The test rotor was subjected to a mechanical and metallurgical test program to determine the properties of the material in the weld-repaired area. Testing included: nondestructive examination of the rotor bore, mechanical analysis of the rotor material, metallographic examination, hardness, tensile, rotating beam fatigue, fracture appearance transition tempreture, J-integral fracture toughness, and stress rupture testing