Enhancing Thermal Efficiency and Temperature Uniformity of Barrel Using Induction Heating

• Main Authors: YEH, GUO-HAO, 葉國皓
• Other Authors: HUANG, MING-SHYAN
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/e26b5d

碩士 === 國立高雄第一科技大學 === 機械與自動化工程系碩士班 === 105 === In the injection molding, the melt quality and stability are both important factors that directly affect the molding quality. The melt quality is depending on the stability and uniformity of barrel temperature. The traditional injection machine uses the resistance heating to perform the barrel heating process, but the resistance heating having a problem of slow heating and low energy efficiency. In recent years, using the induction heating technology in barrel heating has been mention in some research. Fast heating rate and energy efficiency are both advantages of induction heating. However, poor design of induction coil cause serious magnetic field interference. Therefore, how to design a suitable induction coil is the most important challenge for the barrel induction heating. In this study, both of the simulation and experimental method were performed to analyze the magnetic field and temperature distribution under difference barrel shape and coil design. The simulation results show the barrel with grooves has better heating rate and temperature uniformity, and can effectively solve the magnetic field interference by the proximity effect. Single-section barrel heating experiments show that, the heating section thermal efficiency of resistive heating is 51% and induction heating is 86%, the holding section thermal efficiency of resistive heating is 10% and induction heating is 23%, and the holding section temperature uniformity of resistive heating is 79% and induction heating is 68%. Double-section barrel heating experiments show that, the heating section thermal efficiency of resistive heating is 58% and induction heating is 69%, the holding section thermal efficiency of resistive heating is 3.9% and induction heating is 5.4%, and the holding section temperature uniformity of resistive heating is 92% and induction heating is 93%. Simulation and experimental results confirmed that the using induction heating and optimize the barrel shape design can effectively enhance the thermal efficiency and temperature uniformity.