Defect Identification And Detection Of Liquid Ammonia Storage Tank

In the unceasing development of refrigeration industry in our country,most refrigeration enterprises take liquid ammonia as the refrigerant.In the whole operational process of refrigeration system,the storage,transportation,and application of liquid ammonia relate to multiple parts.As the liquid ammonia has corrosion,and the formed ammonia gas after gasification is easy to become explosive gases after it mixing with air,the accidents of poisoning and explosion are easy to occur once the liquid ammonia leaks.Many factors may cause the leak of liquid ammonia,wherein,the defect in the production and use of liquid ammonia tank is the main factor to cause the leak of liquid ammonia.At present,there are many kinds of traditional nondestructive detecting technology that can detect the defect of liquid ammonia tank,but as there are different types of defect,and the detecting technique has certain limitation,when the detecting environment can't meet the requirements of detecting condition of the equipment,it is hard to achieve the recognition and detection of defect.The thesis makes the research about the recognition and detection of liquid ammonia tank based on the refrigeration enterprises relating to ammonia in Lanling.The content of the research are as follows:(1)On the basis of the research on traditional contact nondestructive detecting technology,the thesis compares the advantages and disadvantages of all kinds of technology,and the limitation of the detection to different types of defect.(2)Based on the potential safety hazard checking and controlling project of refrigeration enterprises relating to ammonia in Lanling,which makes recognition and detection of liquid ammonia tank,the problems of the internal corrosion degree of tank wall and the detecting technique of micro leak point have been found.The thesis makes a research on the method of detecting technique.(3)Use non-contact infrared detection technology to carry out detection to the temperature of tank wall.Construct heat transfer model,analyze the influence of material thickness on the temperature in the aspect of theory,choose samples of certain standard to carry out detection,propose the relation curve between temperature and thickness through the data of detection.According to the research result of detecting technique of micro points,use infrared imaging devices,ammonia gas detector and ultrasonic leak detection instrument to carry out detection to leak point of storage tank.