The Safety Assessment And Finite Element Analysis Of Defective Buffer Tank

Pressure vessels are extremely important equipment in the aspects of the chemical and mechanical. Most of the pressure vessel is used under the extreme ambient conditions or harsh terms of their own. And some damages more or less occur on the materials of pressure vessel after a period of usage. These damages will generate different kinds of defects. Crack is the most major defect in the defects of pressure vessel,so strengthen the study of Crack about Pressure Vessel has very important significance.Firstly, standards of countries in the world in terms of the pressure vessel safety assessment were presented. After that, this article assumes a buffer during it was used produce an open type(Ⅰtype) Crack which was in the inner surface of the container body and away from nozzles by non-destructive testing. Then, crack was assessed by simplify and routine assessment, according to the evaluation method in the GB / T 19624-2004 "containing defects in the safety assessment of the pressure vessel”, getting the general failure assessment diagram and simplified failure assessment diagram about this crack. Finally, determining the crack defects can be accepted according to the position in the assessment diagram of assessment point.The method of finite element analysis can be applied to the study of pressure vessels containing defects, and it can obtained the stress intensity factor and the situation of stress distribution of the different forms of defects. It can simulate the buffer tank using the finite element software ANSYS, output related stress cloud and ensure the finite element method is feasible by comparing the stress intensity factor between the finite element method and computing method. It confirms buffer containing defects safety assessment results. Then this paper simulates a variety of factors which affect the stress intensity factor. And it found that when the container wall thickness increasing, the value of KI presented the downtrend; As the size of the crack increasing, the value of KI presented the uptrend; The length of the barrel when conducting the finite element simulation does not substantially affect the values of KI; The greater the pressure in the container, the greater the value of KI; No matter the model 1/2 or integrated model, it does not affect the value of KI When using the finite element software ANSYS simulation This research laid the application foundation about finite element software in defective safety assessment of pressure vessels.