Research On Process Planning And Test For The Parts Of Control Rod Drive Mechanism

The CRDM is the visual plant for working and safety of nuclear reactor. It is amagnetic-jack which operates in vertical steps. Manufacturing process studied of Control rod drive mechanism(CRDM) especially key components of pressure housing assembly is important significance to realize the localization of the generation III of nuclear power equipment.Taking control rod drive mechanism(CRDM) which is the key parts of the generation III AP1000 nuclear power as the research object, in this paper, the pressure housing assembly processing technology and dissimilar metal welding technology are studied by theoretical analysis and experiment.This paper obtains the following research results.Based on in-depth analysis of technology data and function of pressure vessel, the manufacture process of the parts are built on the basis of referencing machining process for both domestic and Foreign.To be solvedthe key problems for position between inside and outside diameter,process the locating datum for the workpiece acted as mutual reference principle again and again is used for machining.It improve the position precision of reference surface. Because the machining characteristics of slender rod of pressure vessel, bending easily, both mechanical model and finite element model for slender rod are established. Simulation and analysis are performed for comparing the influence regularities between center frame and follow-rest. The case of using center frame is built. It can control processing accuracy of bending influence effectively.It can correct positional alignment error of blanks and reach the requirement of position by subsection correction.Researching of dissimilar metal weld of pressure housing assembly, this paper states studied with welding technology of Austenitic Stainless Steel and Nickel-base Alloy from groove dimension and heat input. It built welding process and detection specification based on analysis of metallograph and mechanics experiment.It established fault tree and risk rating list of machining quality, when introducing failure mode and effects analysis(FMEA)for analyzing potential auality risk and compensation scheme. A set of defects tracing procedure and complete quality assurance system is establishedThe manufacturing process is verified by hydrostatic test and nondestructive test and destructive test for Control rod drive mechanism.