The analysis and solution of contact rubbing fault for low pressure rotor of gas-steam combined cycle turbine unit

Abstract

The contact rubbing fault mechanism for low pressure rotor of gas-steam combined cycle steam turbine unit is analyzed deeply in this paper. It is include that the high start and stop frequency of the gas turbine, the special operation mode of the long-time turning and the high designed turbine turning speed are the main reasons for the axial displacement to the inlet side of the fir-tree root and the contact rubbing fault of the low pressure rotor . At the same time, this paper presents a solution to the problem of contact rubbing fault of low-pressure turbine rotor, and analyzes the dynamic stress and vibration frequency of the new blade after technical improvement. The results show that the stress of root and groove of the new blade and the vibration frequency of the new blade can meet the requirements of safe and stable operation of the unit.