Detection apparatus and method

摘要

A detection apparatus arranged to detect defects within a flexible pipe at least partially surrounded by seawater comprises an impedance monitor and a processor. The impedance monitor is arranged to measure the impedance between an electrically conductive member extending at least partially along the length of a flexible pipe and a seawater electrode in contact with seawater surrounding at least part of the flexible pipe in response to an electrical test signal applied to the electrically conductive member at first and second frequencies. The processor is arranged to detect variation of the measured impedance for an electrical test signal at a first frequency, and if a variation of the measured impedance is detected, to determine if the variation is indicative of a pipe defect, and if so to determine the distance from the seawater electrode to a pipe defect by comparison of the measured impedances at the first and second frequencies. Methods of detecting defects within a flexible pipe body, a pipeline apparatus and methods of forming pipeline apparatuses are also disclosed.