Research on Strain and Displacement ILI Technology for Oil & Gas Pipeline

Abstract

The safe and rapid transportation of oil and natural gas, as strategic resources for national energy and power, is one of the important factors restricting the development of national economy. The pipeline often passes some areas vulnerable to geological hazards, placing pipes under the bending stress caused by bending strain apart from normal internal pressure load. Hence, the existence of bending strain on pipeline severely affects the structural integrity and operational safety of pipeline. Especially when any severe defect exists at the position with flexural strain, it may cause the failure of pipeline more easily. This paper proposes an In-line inspection method for pipeline displacement and strain which based on inertial navigation technology. The measurement of pipeline centerline and algorithm of pipeline strain are presented. The method has been verified by pull through and field test. It offers an effective method for safe operation of long-distance oil & gas transportation pipeline in seismic area.