800MW Steam Turbine Flow Path Retrofit Design And Application

The steam turbine is the rotate type prime motor using steam as working media to convert thermal energy into mechanical energy.For normal coal-fired power,nuclear power plant and geothermal power plant,the steam turbine is used to drive generator to generate electric power,and the steam turbine is very important power equipment for modern countries.With the development of China's economy,and the electric demand and supply keep increasing,and the energy-saving and environment-protection requirement is higher than before.In order to reduce the coal consumption of thermal power plant,technological transformation of energy saving and emission reduction of the steam turbine is very necessary.This paper analyzes the original design and existing problems of 1#,2#800MW turbine units in Suizhong power plant,and introduces retrofit purpose,principle,scope,technology and safety,economic performance,technical data,technical feasibility and retrofit scheme.The main purpose of retrofit to flow path of 1# and 2# 800 MW unit is to improve economic performance and safety to realize energy-saving and consumption-reduction and output increase.Based on new design concept of Harbin Turbine Company Limited,the software such as CATIA,CFX-TASC flow,is applied to perform full-3D flow field design for whole flow path of turbine,and determine the retrofit scheme for whole turbine,and optimize design of HP/IP/LP flow path and structure so as to meet optimal object that the heat rate of steam turbine not greater than 7729.5k J/k W.h and rated output up to 880 MW after retrofit.The present issues of steam turbine can be resolved,through optimization of HP rotor,IP rotor and LP rotor,HP nozzle group,HP inner casing,IP inner casing,LP inner casing,diaphragm carriers,HP,IP and LP moving blades,HP,IP and LP diaphragm and stationary blades,sealing and gland seal.After retrofit,the preliminary test of operation is performed,and the test result meet defined requirement.