Research On The Simulation Of Spray Quenching Process Of Nuclear Power Rotor And Composite Spray Quenching Equipment

The research object of this paper was 1000 MW and 1400 MW level nuclear power rotor. The simulation study of the temperature distribution, microstructure and stress distribution of the spray quenching cooling process was finished. The optimal heat transfer coefficient was determined, and the process of rotor spray quenching was made. Considering the influence of pray quenching distance, spray quenching stagnation etc on the heat transfer coefficient, the domestic first sets of nuclear power rotor wind and water(FOG) composite spray quenching equipment was developed successfully. The spray quenching process was conducted for the 1000 MW level nuclear power rotor by using the spray quenching equipment. The measures for improving the equipment design were suggested.The numerical simulation coupling temperature, phase change and stress-strain during composite spray quenching of nuclear power rotor was carried out. The cooling rate, the microstructure and stress distribution were obtained. Simulation results showed thatdifferent diameter parts of nuclear power rotor requireddifferent cooling intensityand cooling wayinorderto ensure performance.The same part of the rotor in the spray quenching process required to use composite spray coolingin order to shortenthe time of water spray, save energy and reduce consumption.The simulation results showed that the influence of water spray heat transfer coefficienton the cooling rate of nuclear power rotor core and microstructure transformation improvement was very small when water spray heat transfer coefficientreached a certain value.Based on it the optimal heat transfer coefficient was determined, and the process of 1000 MW and 1400 MW rotor spray quenching cooling was established.To study the effect of multiple factorsonthe heat transfercoefficient, the relation curves of heat transfercoefficientvs the nozzle diameter D, spray quenching distance H and jet medium temperature T were obtained. The optimal nozzle diameter and jet quenching distance data were made. The results showed that the heat transfer coefficient outside the rotor surface stagnation region decreased rapidly.To ensure axial uniform cooling of the rotor,the rotor rotated while it was cooling.By studying the structure of composite spraying quenching system consisting ofspraying water system, spraying frog system and spraying wind system, multiple key problems were solved,such as themulti nozzle concentric variable diameterstructure, the rotating spreader structure and the supporting steel structure and so on. The domestic first set of nuclear power rotor composite spray quenching equipment was developed, and the experimental test of spray quenching system was completed.Using the composite spray quenching equipment and the process of nuclear power rotor, the production of 1000 MW nuclear power rotor was carried out. The process and equipment were verified. The results of rotor sampling test showed that the mechanical properties of the rotor sampling parts met the requirements. The fluctuation range was small. The microstructure, grain size and inclusion analysis were qualified in according torelevant requirements.According to the results of the process and equipment validation, the process of nuclear power rotor spray quenching could correctly guide the nuclear electric heat treatment.The composite spray quenching equipment could fully complete the nuclear power rotor heat treatment. This paper put forward the further optimization measures for the compound spray quenching equipment, which laid a technical foundation for the future development of the 1400 MW nuclear power rotor equipment.