Development of new pipeline maintenance system for repairing early-built offshore oil pipelines

This paper introduces a set of new pipeline maintenance system for early-built long-distance offshore oil pipelines. An on-line intelligent inspection pig is developed using ultrasonic tool to detect defects in oil pipelines and the acquired data is stored for off-line analysis. Through analysing the data, defects can be found, sized, classed, and besides, the plan to locating them is made. An autonomous pipeline robot is developed to carry out the locating defects tusk, which adopts the way of detecting girth welds, combined with odometer wheels to locate the defects' position, so the problem of locating defects in early-built offshore pipelines unequipped with magnetic markers is solved. The paper introduces major components of the intelligent inspection pig and the autonomous pipeline robot and describes the process of maintaining offshore oil pipelines with the developed system.