The surface accuracy of the sealing plate in aircraft movable rotating structures directly determines the assembly clearance of the rotating body. However, as a thin-walled component with a complex spatial curved surface, the sealing plate faces challenges such as manufacturing rebound and assembly deformation, leading to difficulties in shape control. This paper proposes a rapid detection method for dynamic shape deviations of rotating components based on digital 3D measurement technology. Firstly, a cylindrical coordinate system is established by fitting rotation axis parameters from scanned point clouds. Secondly, the outer contour points of the seal plate are extracted to generate 2D profile curves. Finally, dynamic shape deviations are calculated through comparison with ideal digital models. Experimental verification using 3D-printed mock-ups demonstrates that the proposed method can accurately extract outer contour lines of rotating bodies, with deviation calculation results matching the mock-up manufacturing accuracy. Moreover, it effectively identifies interference risks. This methodology provides reliable technical support for dynamic clearance analysis and optimization of rotating components.