Analysis And Improvement Of The Processing Technology Of 30MW Turbine Rotor

Rotor is the core part of energy conversion in steam turbine.Its function is to turn high temperature and high pressure steam into rotating mechanical energy and output power.The rotor is subjected to very complex forces during operation,mainly including torsion,centrifugal force and thermal stress.Therefore,its structural form design,material selection and processing technology are facing severe challenges.The rotor stability plays a vital role in the operation of steam turbine,the rotor unbalance amount is small,the rotor during rotation beating is smaller,more stable rotation,so the machining precision of rotor machining has a very high demand,so the design of a comprehensive manufacturing process,to ensure the accuracy of the rotor in the processing and installation is very important.In this paper,the effect of cutting speed,feed rate and cutting depth on surface roughness is studied by single factor test,and the optimum processing parameters are determined.Through the study of dry cutting,cooling liquid and compound spray method,it is determined that the combined spray method is the best and the most economical method.Based on the processing of steam turbine rotor speed and feed rate and cutting depth are tested and analyzed,find out the three relations between surface roughness and machining parameters,easy to determine.Through the study of the non coolant cutting,the coolant and the compound spray method,it is found that the combined spray method has the best cooling effect.For each part of the rotor,and the difficulties in the process of analysis,research and development of a specific tool bar,for the rotor slot between the steam sealing teeth,ensure accurate processing;a rotor machining process for clamping and locating rotor processing platform is designed.Which is to ensure the machining precision,and greatly reduce the clamping positioning time;design and improvement of the rotor machining process,including machine tools,cutting tools,and detection,and determine a reasonable processing parameters,completed the optimization of processing technology of rotor.A systematic and comprehensive analysis is made of the machining difficulties in the machining process of the rotor's locking ports,wheel grooves and balancing holes,and the cutting tools,processing methods and technological parameters are optimized and improved.For rotor slot processing,using separate machining tool,improve processing efficiency and utilization rate of the tool,meet the machining precision of the parts will be better;for the balance hole processing method,through the design of the new cutter and processed in the Mitsubishi machine,to solve the pressure stage impeller,balance hole span not in drilling problems,and ensure the machining precision and quality of the rotor;optimizing the processing of the lock,the NC programming processing through the use of UG,locking higher precision,surface quality is more beautiful,and time-saving and labor-saving.