This document is an expanded abstract.
Oil flowlines are two to twelve inches in diameter pipelines, most susceptible to corrosion and very difficult to inspect. Since the flowlines are connected to the well head and closest to the wells, they are exposed to the highest pressures and temperatures thus most susceptible to corrosion. Since flowlines are small in diameter, most of them do not have launcher and retrieval stations thus almost impossible to inspect them using In-line Inspection (ILI) smart PIGS. Due to inability to inspect the flowlines, accidents occur with flowlines every month. A corrosion monitoring system is thus absolutely necessary to prevent accidents from happening with flowlines.
The aim of this research project is to introduce new or improved methods for monitoring and detecting corrosion of onshore exposed flowlines by developing fiber optics based external and internal corrosion detection sensors. It is hoped that the same external corrosion detection sensor can be also used to detect oil leakage.
Developing corrosion detection sensors for oil and gas pipelines is a monumental task since there are many different material types for oil and gas pipelines, pipeline diameters, and wall thicknesses in service. Onshore, there are pipelines above the ground, pipelines completely buried under the ground, and pipelines partially buried and partially exposed. Offshore, there are pipelines sitting underwater on the seabed or completely buried under the seafloor with both pipeline types subject to marine growth. There are 2 to 12 inches flowlines with different wall thicknesses, and 8 to 48 inches transfer or transmission lines with different wall thicknesses. Externally, there may be pipeline insulations, coatings, paints or marine growth, and internally, there may be coatings, scale, asphaltene or wax build up.