The cylinder block of main pump is a mechanical part that produces pressure through relative motion with piston. At this moment, the relative movement between the cylinder block and the piston may cause a seizure, and this seizure problem can be solved by pressing a bushing into the cylinder block. However, if the rates of shrink fit are insufficient, the copper bushing will be detached from the cylinder block and rates of shrink fit are excessive, a residual stress higher than yield stress of material will be generated and adversely affect the durability of vushing and cylinder block.
Therefore, in this study, a clear and quantitative rates of shrink fit is presented to solve the above mentioned problems, and to correct the durability assessment process of mechanical parts where residual stress occurs is performed. The results of this study are expected to be based on durability assessment of mechanical part with complicated production process.