Research And Application Of High Vacuum Sintering Process Control System

For the domestic current production technology of samarium cobalt permanent magnet materials, the high vacuum sintering process control system of the manufacturing enterprises of samarium cobalt permanent magnetic is the object of this study. And by combining the aspects of computer control, the technologies of sensing detection and the aspects of fieldbus, the high vacuum sintering process automatic control system with good stability, high reliability and high cost-efficiency is proposed in this paper.This topic does research into high vacuum sintering process, designed the efficiency and reduce the energy of frames including presintering, sintering and cooling, and developed by control system to control temperature, vacuum degree and pneumatic actuators in sintering process. The programmable logic controller(PLC) works as the center of this system; the touch screen and operating buttons can be used to control the system; several kinds of sensors can be used to collect data regarding temperature and vacuum degree; each pneumatic value can be altered according to the process. All of these will realize the automatic control of high vacuum sintering process. Finally, the PC management system is designed to monitor the operation, to realize remote control and to save and display the data, etc.The temperature detection module based on ADu C845 is proposed according to the aspects and requirements of the sintering process. The temperature collected by temperature sensor can be handled and then be uploaded to the PLC through the temperature detection module equipped with the external interface of PLC communication. This module possesses the features of high precision, high stability, which assures the high accuracy of testing subsystem.The control system is mainly divided into four subsystems: center control subsystem, temperature control subsystem, pneumatic control subsystem and PC monitoring subsystem. Besides, center control subsystem is the core part of this system, which is used to cope with testing data, to issue control instruction and to deal with malfunction and so on.The system has been used by the company, it has been keeping a stable and safe operative condition since it was installed, which indicates that this system could satisfy the real application requirements of easy operation, stability, strong resistance to interface and so forth.