Abstract: For parts with complex surfaces, a 3D scanning measurement method for full profile was proposed. To obtain the shape deviation of the part, the scanning model was built by reverse modeling and used to compare with the design model. The proposed method was used to measure the blade out arc hollow parts of a large nuclear power steam turbine, and then compared with the designed model. The measuring results show that the largest positive and negative deviations are 2.59 mm and -3.03 mm, respectively. Compared with the traditional special fixture, the 3D full profile measurement method can be used to measure various complex parts rapidly, and it has the characteristics of full data and high precision. To solve the springback problem of the part, springback compensation for the part with complex surface based on reverse engineering was introduced. After springback compensation for the blade out arc hollow part, The molds were processed and tested. The results show that the final largest positive and negative deviations are 1.36 mm and -1.43 mm, which meet the requirement of the shape deviation of that part.

Key words: material synthesis and processing technology, reverse engineering, springback compensation, mould, complex curved surface