A Study On The Theory And Method For Assessment Of The Pressure Pipelines

Pipeline is very important in industrial production which is used in the delivery of medium materials of special properties, such as high-temperature, high pressure, flammable, explosive, toxic.Once the pipeline is damaged, it will cause serious consequences to the state and the people, causing major losses. In order to ensure the pipelines can operate safely, people must do some necessary safety evaluation.Therefore, this paper, which studies the theory and method of safety evaluation on pressure pipeline, is of great theoretical significance and economic value.There is a lot of work to be done in the research of pipeline safety evaluation technique. Just a small part of research work is done in this paper. The main research content is as follows:1 Systemically analyzes and research on the theory and methods of the current existing pipeline safety evaluation. Seek more scientific and reasonable pipeline safety evaluation methods and improve pipeline safety evaluation criteria.2 Comprehensively analyze the impact of high temperature on materials and corrosion mechanism of hydrogen and the impact of hydrogen on properties of materials. Collect and sort high-temperature mechanical properties of various grades of carbon. The types and mechanism of hydrogen damage, and the properties degradation of materials are preliminarily discussed.3 Calculate stress intensity factor and J integral of the pipe surface crack with finite element method. First calculate a number of new pipeline axial stress intensity factor data by using finite element method. On this basis, systemic summary of the stress intensity factor of pipe crack is done. Then sort and compare various calculation methods of J-integral. Compile J-FEM program of pipe calculation by using ANSYS APDL language in secondary development.4 A lot of time needs to be spent in calculating the crack pipe characterization parameters with finite element method and only some discrete points of data can be obtained, so this paper presents the method of neural networks to resolve these two issues.Establish the artificial neural network expert system. Through computer simulation results show that the system is very accurate and reliable.