Analysis on Spalling Reason of Babbitt Layer of Steam Turbine Bearing of Ultra Supercritical Unit

The spalling reason of Babbitt layer of steam turbine lower bearing of one ultra supercritical unit was analyzed by means of chemical composition analysis, X-ray diffraction, metallographic examination and so on. The results showed that the chemical composition of the Babbitt layer significantly deviated from the requirement of GB/T 1174-1992 standard and the proportion of ε and β ′ phase was exorbitant resulted in the spalling. It was suggested that the control of the quality and manufacturing process of the bearing must be emphasized.