Plastic is common in daily life. The need for plastic keeps rising along with population growth. Ethylene vinyl acetate, or EVA, is one of the most used plastic. EVA is obtained from the synthesis of ethylene with vinyl acetate. One of the tools commonly used to produce EVA is the autoclave reactor. The autoclave reactor is a vessel that works at a temperature of 150-230 °C and a pressure of 1000-3000 atm. A common problem that often occurs in autoclave reactors is bearing damage. This research uses optimization methods to increase bearing life. This study chose two parameters, namely the number of impellers, temperature, and used bearing life as a response. Experiments in this study used Ansys software for simulation, which was validated using data from the company. Then the experimental results were optimized using the Taguchi method and Response Surface Methodology (RSM) assisted by Minitab software. These two methods are compared to find out which method gives better performance. The study results show that the two methods have similarities in that the parameter that significantly influences the response is temperature. Both methods also get the same optimal parameters, namely when: the number of impeller is 7, and the temperature is 150 °C. Simulation results using optimal parameters obtained an increase in bearing life of 3.095% compared to the initial design. The difference between the two methods is that RSM provides more detailed information about the effect of the relationship between factors and factor squared on responses. RSM is more accurate in predicting the response value under optimal conditions with a prediction error of 0.009%, while the Taguchi method has an error prediction value of 0.4208%.

Plastic is common in daily life. The need for plastic keeps rising along with population growth. Ethylene vinyl acetate, or EVA, is one of the most used plastic. EVA is obtained from the synthesis of ethylene with vinyl acetate. One of the tools commonly used to produce EVA is the autoclave reactor. The autoclave reactor is a vessel that works at a temperature of 150-230 °C and a pressure of 1000-3000 atm. A common problem that often occurs in autoclave reactors is bearing damage. This research uses optimization methods to increase bearing life. This study chose two parameters, namely the number of impellers, temperature, and used bearing life as a response. Experiments in this study used Ansys software for simulation, which was validated using data from the company. Then the experimental results were optimized using the Taguchi method and Response Surface Methodology (RSM) assisted by Minitab software. These two methods are compared to find out which method gives better performance. The study results show that the two methods have similarities in that the parameter that significantly influences the response is temperature. Both methods also get the same optimal parameters, namely when: the number of impeller is 7, and the temperature is 150 °C. Simulation results using optimal parameters obtained an increase in bearing life of 3.095% compared to the initial design. The difference between the two methods is that RSM provides more detailed information about the effect of the relationship between factors and factor squared on responses. RSM is more accurate in predicting the response value under optimal conditions with a prediction error of 0.009%, while the Taguchi method has an error prediction value of 0.4208%.

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