The laying of buried pipelines in difficult engineering and geological conditions is associated with the need to take into account a large number of factors affecting the process of pipeline operation. It is practically impossible to take into account all these factors at the design stage. In this regard, methods that make it possible to assess the technical condition of the pipeline at a specific point in time acquire particular relevance. One of the promising methods for assessing the technical condition of underground pipelines is to survey the depth of the axis of the underground pipeline from the ground surface with subsequent use of the data obtained to assess the level of bending stress. The low popularity of this method lies in the large errors obtained in the calculations according to the developed methods. In the work, the reasons for the occurrence of significant errors in determining bending stresses when using survey data were analyzed, mathematical dependencies were proposed that make it possible to evaluate bending stress based on the data obtained with the accuracy specified at the design stage of the experiment. Calculations are provided that confirm the adequacy of the proposed mathematical models.
The feature of the operation of main underground pipelines in complicated engineering and geological conditions is the need for constant monitoring of their technical condition and the design position of the axis to assess the level of bending stress in order to take preventive measures. The existing methods for monitoring the technical condition of underground pipelines have several disadvantages, for this reason, as a rule, a set of methods is used.
One of the promising methods for assessing the bending stress of underground pipelines is the method of surveying the depth of the pipeline axis from the ground surface. The paper provides dependencies that make it possible to level the errors arising when using this method and to assess the bending stress of an underground pipeline with an error not exceeding the specified one and taking into account the design features of the pipeline and the equipment used.
Comparison of the calculated values of bending stress when using the method of surveying the depth of the axis of an underground pipeline from the ground surface and the values obtained during smart pigging of a section of an underground pipeline is presented. The provisions for determining the optimal shooting step when measuring the depth of the pipeline axis from the soil surface are presented.
In this paper, it is proposed to investigate the influence of the parameter providing the rate of pipeline coating degradation on the protective length of cathodic protection systems (CPS). Comparison of the calculated values of the pipeline coating resistance with the predicted values is carried out according to the theoretical distribution of the pipeline coating resistance in time. The difference between the practical value of the parameter providing the rate of coating degradation of the considered pipeline section from the predicted one is determined. The dependence of the parameter providing the rate of pipeline coating degradation on the protective length of the CPS has been formed, which makes it possible to reduce the number of cathodic protection stations along the pipeline path at the design stage, and to diminish their energy consumption in the electrochemical protection system from corrosion of oil and gas pipelines.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.