Estimation of Reliable Replacement Time of Cutting Tool in Tooling Machines Using the Energy-Based Reliability Model (ERM)

Real-time monitoring systems have been developed for tooling machine for the purpose of investigating the time-dependent cutting conditions, to detect instantaneous events, and to estimate life of cutting tools and the machine itself. An Energy-based Reliability Model (ERM) has been developed for real-time monitoring of cutting conditions. A standardized inspection process was defined and the two most sensible signals, vibrational signals and temperature increments, are collected to monitor the accumulation of dissipated energy during the tooling processes. The ERM then computes the normalized accumulative dissipated energy in replace of evaluating surface quality of workpiece at the end of each tooling process. This paper focuses on the implementation of ERM in the turning process on a lathe. The experimental results showed the dissipated energy linearly grows with respect to the amount of volume removal from the workpiece. The ERM built from the experimental results under the same condition were then utilized to estimate the turning performance under different experimental conditions. As a result, similar trends of dissipated energy versus volume removal were found. Therefore, ERM can be utilized to estimate a reliable replacement time of cutting tool in tooling machines.