Research On Micro-crack Detection Method Of Plate Heat Exchanger Plate Based On Machine Vision

The plate heat exchanger plates are the core components of plate heat exchangers,and micro-cracks may occur during the stamping production process.If the plate heat exchanger uses plates with microcracks,there will be a risk of leakage.Once the raw material leaks in industrial production,it may cause economic and environmental problems.Therefore,strict inspections must be carried out after the production of the plates to ensure that the defective plates will not be put into use.Manual visual inspection and penetrant flaw detection are commonly used in the industry to detect micro-cracks.Manual visual inspection is difficult to ensure the accuracy of micro-crack detection;the traditional penetrant inspection method has complicated processes,and the real-time performance of micro-crack detection is poor.A micro-crack detection system for plate heat exchangers based on machine vision is designed.The detection algorithm of the system adopts image processing technology,and the application program of the system is developed based on the MFC graphical interface development library.The system has been tested completely,and the results show that the system can run stably and meet the design requirements.The main work of this paper is summarized as follows:(?)The research status of micro-crack detection and the reasons for the formation of micro-cracks in plate heat exchangers are analyzed,combined with the actual needs of industrial production and the requirements of industry standards,the system design indicators are formulated.(?)The characteristics of different region segmentation and feature enhancement algorithms are analyzed,and appropriate preprocessing algorithms are designed for the detection of micro-cracks to meet the needs of micro-crack extraction.(?)A micro-crack extraction algorithm based on edge detection and line detection is designed,and a comparative analysis is carried out in terms of detection accuracy,calculation speed and system requirements.(?) Various characteristics of micro-cracks are analyzed,and the quantification method of each characteristic and the micro-crack characteristic constraint set combining multiple characteristic constraints are designed.Experiments show that the feature constraint set can effectively remove a large number of false detections.(?)The human-computer interaction interface of the system is designed,and the designed algorithm is embedded in the application program to realize the complete function of the system.