The quality control method for remanufacturing assembly based on the Jacobian-torsor model

To improve the assembly accuracy of remanufactured parts with multiple heterogeneity and properties, and to guarantee the quality of remanufacturing product no worse than the original one, this paper takes the air tightness of remanufactured engines’ cylinder block and head as the research target and proposes a quality control method based on the Jacobian-torsor model for remanufacturing assembly. First of all, three different Jacobian-torsor models for assembly tolerance are structured, and according to that, the defined torsor difference (∆FR) of remanufacturing products is calculated by considering the geometric error of remanufactured related parts assembly influenced by the temperature field and force field. Then, the optimal tightening torque of cylinder heads’ main bolts corresponding to ∆FR is achieved by applying the bivariate Lagrange interpolation method. Finally, taking the assembly of remanufactured engines’ cylinder block and head as a case study to verify the proposed methods is feasible and effective.