Improved Methodology for Identification of Buried Casings using Indirect Inspection Method

摘要

Even though casings protect the carrier pipe from mechanical damage and external loads, they may create problems and require excavation for inspection and repair. There are several instances where accurate details on casing location is not available. Identifying the unknown locations of the casings to replace, remove or perform maintenance is a major cost for pipeline operators. These challenges could be a concern for pipeline integrity for pipelines that cannot be pressure tested or prohibit the use of In-Line Inspection (ILI) tools, because completing direct examination or performing Direct Assessment (DA) at an unknown casing location would be challenging. This paper will show how an indirect inspection technology can be used to find buried casings without any direct contact to the pipeline or ground disturbance. In addition, the paper will share how to find these casings based on the change in the magnetic field on the pipe. This paper will present results from previous inspections and share visuals of final processed data.