Research And Application Of Quality Improvement Technology For Axial Blade Assembly

As the work of ultra-low emission and energy saving of coal-fired power is in full operation gradually in the country,higher steam turbine units efficiency and less coal consumption become new requirements.The goal in making steam turbine units turns into high power,high speed and long and thin axis,and problems such as rotor balancing become outstanding.A turbine blade is called the ‘heart' of a steam turbine,and its processing and assembly accuracy will directly affect the balance of a rotor,which then affect the safety of a turbine unit as a whole.Therefore,the research on improving the quality of blade assembly is of great urgency.At present,the power machinery enterprises are facing problems of long assembly cycle,poor assembly quality,wrong tooth fit clearance after balance,and blade fracture,in producing and assembling steam turbine axial blades.These problems are making great impact on efficiency and safety of producing steam turbine units.Therefore,the research on improving the quality of blade assembly has a certain value and is of great significance.To shorten assembly period,improve assembly quality,cut maintenance cost of axial assembly blades,the paper starts from the study of assembly requirements,analyzes the current status of assembly,proposes several key technologies to ensure the quality of assembly,and provides systems analysis,optimization and improvement for the technologies.The main research topics include: the analysis and optimization of the blade root and wheel groove fit clearance;analysis and determination of the reasonable amount of blade thickening;the improvement and process simulation of blade manufacturing process and the realization of a single blade precision processing technology;making diagnosis in advance and reducing workload in actual assembly process,via the virtual assembly technology and at last,implementing and verifying the results on a specific power equipment enterprise's steam turbine unit,and applying the results into the procedure.The results can greatly improve the quality of steam turbine unit assembly,keep blade radiation position,reduce the amount of unbalance in rotor dynamic balance and improve the safety of units.At the same time,they can also greatly shorten the assembling period and cut maintenance cost.