Study On Residual Strength Assessment Technology For Oil/Gas Transportation Corroded Pipe In Service

The pipeline is very important in the exploitation of petroleum. Oil and gas pipelines are prone to corrosion due to the effect of the environment and production transported. The residual strength of pipelines corrupted must be evaluated so that the correct decisions can be making: the pipeline can continue to service, require to been maintained or must to be replaced.The residual strength assessment of pipelines corrupted is a new pattern management technology about more 30 years. It has strong practice. In addition, the conditions of oil-and-gas pipelines are very complex, so in the earlier of its' development, it took long time to apply, prove and consummate it gradually. Today, many countries take active parts in spreading this new technology to safety assessment of oil-and-gas pipeline.Firstly, this paper sets forth in brief the development background and technology, investigation practice, science bases and appliance effect of the residual strength assessment technology of oil and gas pipeline assessment. It puts forward the study intention aad detailed study containing and also frames the proper technique courses.Based on the colligation anglicizing and comparing the existing methods of residual strength assessment, this paper the practice of the pipeline producing, installing, operating and managing, this paper refers to the regular index assessment method and investigates the fuzzy collocation assessment method of the petroleum-and-gas pipeline.Next, the various methods of residual strength assessment are analyzed and compared synthetically. The mechanics fundamentals and principles of this technology are introduced. The basic hypotheses are erected. The size model and mechanics model areestablished and consummated according to the damage degree of the pipeline corrupted and to the forces at the pipe wall in various laying manners. And established residual strength limitness for Corroded Pipe.Again, taking the maximum allowing operation pressure (MAOP) as assessment rule the new method of the residual strength assessment of various corrosions is put forward based on the existing assessment methods. The multilevel assessment system of corrosion defects is erected, which carries grade assessment according to the criterion from simpleness to complexity and from conservation to accusation.Finally, based on the fundamental theories of the structural reliability and the true condition of the corroded pipeline, the assessment model of which is established and is carried out. The relative software of the residual strength assessment for corroded defects in long distance pipelines of oil and gas is presented in brief.