Case Analysis Of Steam Seal Retrofit For 600MW Unit Steam Turbine

The development of electric power industry has a direct impact on the speed of development of national economy,and the power industry provides power for all fields of national economy.There are many kinds of power plants,in our country,accounting for three of the order of thermal power,hydropower and nuclear power.Among them,thermal power and nuclear power,are the steam turbine as the energy conversion of the medium to power generation.More than 80% of the electricity is provided by the steam turbine generator unit.The turbine technology is advanced or not has great influence on the development of the electric power industry.At this stage,China's power industry is at an unprecedented pace.At the same time,steam turbine on the function and structure of the continuing problems especially in the old steam turbine is gradually phased out,the new type steam turbine,the transformation of steam turbine components a new becomes increasingly important.Wushashan power plant steam turbine is Harbin steam turbine plant with the introduction of production technology design of 600 MW supercritical unit,although designed heat consumption rate for 7530.20 kJ/(kWh),but due to constraints of domestic manufacturing technology and equipment installation level,combined with on-site maintenance process and actual operation status,it is believed that the actual heat consumption rate about 7745 kJ/(kWh).In view of the 600 MW unit in Wushashan power plant steam seal transformation,analyzes the necessity of reform,establish the transformation goal,on high pressure cylinder stage steam seal,high pressure and low pressure cylinder seal cylinder at the end of grade three diaphragm seal scheme in detail.In order to find out the unit after the transformation of the actual operation and the effect of #2 after the modification,respectively in 600 MW,450MW,300 MW under the condition of the thermal performance test and other economic and technical index,rate of high pressure cylinder efficiency and unit consumption determination unit of heat.The results show that the modification effect of steam seal is remarkable.