Mechanism Research And Motion Analysis For Nuclear Power Plant Pipeline Special-profile Weld Inspection Equipment

This paper aims to design and develop a suitable vortex video scanning device fornuclear plant control rod drive mechanism (CRDM) lower Ω weld. Considering the CRDMarrangement and available space, scanning device stretches in the radial direction in thecircumferential scanning manner to do the eddy current inspection. This equipment iscomposed of a base, telescopic mechanism,vertical auxiliary support mechanism, scanningterminals, four parts which mainly complete the non-destructive testing tasks with thescanning eddy current probe installed in the terminal.The main content and the innovation of this paper are:First, to complete the design of the virtual scanning device prototype, come up withthe draft, process based on the draft, and to complete the assembly and debugging in thelater period. This can help complete the scan work of the weld Ω eddy current video at thelower part of CRDM.Second, after the completion of the virtual prototype design, it uses Pro/MECHANICA to do finite element analysis for the key components of scanner. Then itoptimizes component design based on the analysis results in order to make the stress ofparts and the deformation of the parts adapt to the mechanical properties of materials andensure the security and reliability of the usage of parts.Third, with the kinematic analysis on the scanning device, it uses D-H rule to obtainthe homogeneous transformation matrix between the coordinate system and then to obtainthe scanner probe’s pose position and orientation. Next, it implements the inversekinematics analysis, which provides reliable kinematics ground for the deeper intelligentcontrol of the scanning device. Finally, it uses the “mechanism module” in Pro/Engineer todo the motion simulation for the scanning device. These parameters will be used to verifythe rationality and effectiveness for the scanning device design and kinematic analysis.