A numerical approach to energy savings in heat drying process of drilled and water-cleaned PCB

摘要

The post-drill cleaning process, one of processes to manufacture Printed Circuit Boards (PCBs), can be divided into water cleaning and heat drying processes. The various contaminants occurred during the drilling process are removed in the water cleaning process. The remaining moisture after this process is thoroughly removed by vaporization during the heat drying process. In this paper, the heat drying process of PCBs that have been drilled and water-cleaned prior to drying, is modeled and investigated for a Computational Fluid Dynamics (CFD) analysis. The Human-Machine Interface (HMI) system configured by using the Ubiquitous Sensor Node (USN) and the Machine-to-Machine (M2M) device is proposed in order to measure interior temperatures of the drying system and to define boundary conditions for the CFD analysis. Currently, six heaters are in operation by workers for the heat drying process as customary. However, it was shown through the experimental measurement and numerical analysis that the heat drying process is possible with operating only 4 heaters. The electrical power consumption of the case where 4 heaters are operated shows 33% of decrease from that of the case where 6 heaters are operated. For a near future study, a structural improvement of the drying system will be proposed with research on parameters that are influential on the performance of the system as one of the measures for a further reduction of electrical power consumption.