A New Method for Precision Measurement of Wall-Thickness of Thin-Walled Spherical Shell Parts

Thin-walled parts are widely used in shock wave and detonation physics experiments, which require high surface accuracy and equal thickness. In order to obtain the wall thickness of thin-walled spherical shell parts accurately, a new measurement method is proposed. The trajectories, including meridian and concentric trajectories, are employed to measure the thickness of thin-walled spherical shell parts. The measurement data of the inner and outer surfaces are unified in the same coordinate system, and the thickness is obtained based on a reconstruction model. The meridian and concentric circles' trajectories are used for measuring a spherical shell with an outer diameter of phi 210.6 mm and an inner diameter of phi 206.4 mm. Without the data in the top area, the surface errors of the outer and inner surfaces are about 5 mu m and 6 mu m, respectively, and the wall-thickness error is about 8 mu m with the meridian trajectory.