Intelligent computing methods used in acoustic emission and magnetic flux leakage detection of tank bottom

Abstract

As the main equipment for petroleum and petrochemical raw materials and products storage, storage tanks are widely used in petroleum and petrochemical companies. The safe operation of storage tank is the precondition of normal production. The tank bottom is the highest risk for it is always used under the composite medium, some of them is very corrosive and often causing tank bottom failure. For the tank bottom belongs to the concealed work which always runs under the corrosive composite medium circumstance, and the bottom defect couldn't find by daily inspection. So, the newly developed acoustic emission detection technology is emerging, which has advantages of online detection and avoiding the expense and risk of opening the tank. But the acoustic emission detection has disadvantages of give qualitative results, which couldn't give the accurate remaining thickness of the tank bottom, so the magnetic flux leakage detection is developed which can give the quantitative results. These two methods have their own merits and demerits, so the two methods are often used together in the practice. Recently, our institute in accordance with the requirements of the group company safety and environmental protection department to carry out a large number of acoustic emission testing work online in order to avoid the tank perforation, two hundred tanks of DAQING oil field, LIAOHE oil field and other oilfield belong to CNPC were tested by acoustic emission detection technology and forty tanks of these tanks were testified by magnetic flux leakage detection technology when opening the tanks. The results show that the two detection methods can reflect the corrosion of the bottom of the tank well, and can provide decision support for the daily management and maintenance of the tank.