Analysis of the Effect of Machining Sequence on Machining Error Considering Workpiece Rigidity Change

Abstract

Abstract The objective of this research is to investigate relations between individual physical phenomena and machining error from the measured machined error. Small lot production using numerical control machine tools is widely applied to high quality and high value-added products. In such production, agile and flexible machining is required. Thus, there have been many researches which investigate the effect of specific phenomena such as cutting force, thermal expansion, tool wears, chattering vibration and so on, which is to realize high precision machining. However, there have been some unsolved problems. The first problem is focused phenomena are mostly cutting force and/or machine tool deflection. Accordingly, other effects such as the results by workpiece rigidity change have not been investigated enough. The second problem is that the generation process of machining error is complicated and there is no proper method to compensate. Because of those complicate process, it is difficult to determine the dominant error factor of a new machining case in advance. Therefore, on-machine error measurement and estimation of error factors are essential technologies in order to achieve accuracy assurance. Recently, machining for rib-structured and thin-walled workpiece becomes important because of their higher structure efficiency and light weight characteristic. In this paper, the effect of workpiece rigidity to the machining error is investigated. Depend on the machining sequence, workpiece rigidities change differently during the machining process. Two different machining cases with different machining sequences are conducted and difference between the cases are investigated.