Study On Thrust Bearing Design Of Canned Motor For New Type Nuclear Main Pump

The nuclear main pump is an important part of the reactor circulating system,while the main pump bearing is the most important part of the nuclear main pump.The new type nuclear main pump is designed by shielding pump structureThe main pump unit is composed of a shielding motor and a pump body.The pump and pump form a vertical structure.Due to restrictions on operating environment conditions,the main pump motor thrust bearing can only be used as lubrication medium with water,due to the low viscosity of water,increasing the establishment of fluid lubrication difficulty,which directly affected the bearing capacity and allowable friction.Therefore,in addition to reasonable structure design,the selection of friction secondary materials is especially important for the main pump bearing.At present,water lubricated bearings are mostly made of graphite material.Although they have the advantages of self lubrication,but the wear resistance is not enough,it has been unable to meet the requirements of the new generation of nuclear main pump for bearings,thrust bearing has become one of the components that restrict the reliability of the main pump.In view of the existing problems,in order to solve the reliability of the main pump thrust bearing and improve the safe operation life of the bearing,this paper mainly carried out research work in the following aspects:Firstly to optimize the design of bearing structure,according to the main pump working condition,design of structure parameters of the test bearing,the bearing friction optimization of thrust bearing performance calculation and further study on finite element analysis.Secondly the feasibility and technical analysis of the main pump shielding motor,thrust bearing and new wear-resistant material are carried out.Considering the physical characteristics,mechanical properties and processing technology,the friction pairs of the test bearing are determined.A new composite material for thrust bearing under special working conditions of nuclear main pump is developed.Finally through the establishment of simulation of main pump running conditions on the test bearing to carry out verification test in the laboratory for concrete in water lubricated thrust bearing test device,the actual operating condition simulation of pump units,to carry out research subjects bearing friction and wear test,test results can meet the requirement of the use of nuclear main pump.Through the research work,the research and development of a main pump bearing excellent performance,the results of the study will be applied to new nuclear main pump thrust bearing design,is bound to the nuclear main pump safe operation and power production is of great significance.