Quantitative Evaluation Of Carburizing Damagage Of Ethylene Cracking Furnace Tube And Magnetic Detectiong Technology

Ethylene cracking furnace is an important device in petrochemical enterprises,with furnace tube as its core component.The operation of furnace tube of ethylene cracking furnace affects the sound operation and production cost of the enterprise.In the process of using ethylene cracking furnace at home and abroad,the problem of carburizing damage of furnace tube is frequent,but at present,there is a lack of quantitative analysis method for the structure and performance inside and outside the carburizing zone of the furnace tube in service,and it is difficult to check in a non-destructive way.In this paper,the quantitative evaluation of carburizing damage of ethylene cracking furnace tube is carried out,and the magnetic detection technology of carburizing damage of ethylene cracking furnace tube is explored.A carburizing layer thickness detection system for ethylene cracking furnace tube is developed by combining PLC and magnetic sensor.1.Quantitative study on the relationship between the structure and properties of carburized layer of furnace tubes in service in ethylene cracking furnace.Through metallographic examination,scanning electron microscope,X-ray diffraction,chemical composition analysis and mechanical property test,the relationship between the structure and performance of carburized layer of ethylene cracking furnace tube in service for a long time is explored:a quantitative relationship between the microstructure inside and outside the carburized layer of furnace tube and its corresponding mechanical properties is found.At the same time,the failure and damage mechanism of the test furnace tube in the subject is discussed,and three life evaluation methods with high correspondence and applicability are used for simple life evaluation and analysis of the test furnace tube in the subject.2.Research on magnetic detection technology of carburizing damage of ethylene cracking furnace tube.Combined with metallographic test and mechanical property test,the corresponding relationship between the magnetism and carburization of ethylene cracking furnace tube is explored through two kinds of magnetic testing tests(magnetic coercive force test and magnetic force test),and the advantages and disadvantages of the two kinds of magnetic testing tests and their application prospects are compared.3.Based on PLC and magnetic sensor,the thickness detection system of carburized layer is developed.Based on the existing furnace tube with carburizing damage and the principle of magnetic testing,a software and hardware system of magnetic testing for carburizing layer of ethylene cracking furnace tube based on PLC is developed,which includes sensor selection,PLC selection and communication settings,and Visual Basic Six This paper introduces the programming and setting of PC monitoring interface,and verifies that the system can meet the detection task under the actual maintenance condition through the test.