The Research On Autocontrol Protection System For The Check Valve Of Axial Flow Fan

This article concentrates on the check valve for axial flow fan, to work out an autocontrol protection system for the check valve. The system will lift the value lead to reduce the loss of pressure head which can increase the production of steel of blast furnace, on the condition of never disturbing the work of check value, when the flow rate in the ventilating duct is regular. The mechanical part of the system uses electromagnet and three phase alternating current motor as the power to lift the value lead. A PLC will dominate the control process, and to increase the reliability of the system, we make a redundancy control module by 51-serial single-chip microcomputer. We also program a supervisory control system in the host computer by LabVIEW, a graphical software system, to give facilities for the operating crew to control the system and check the history data. We use serial communication and CAN fieldbus to connect the PLC control system, the redundancy control module and the supervisory control system. The autocontrol protection system has high reliability and can run a very long time without stop. The system also can be expanded.The most important characteristic of the system is the mechanical part can ensure the normal work of the check value even if the control part is out of work. And the redundancy control module works with the PLC, which increases the reliability of the system. The well ordered human-computer interface of the supervisory control system which programmed by LabVIEW makes it easier for the operating crew to adapt it.After further proof-test, this autocontrol protect system has the value to be generalized.