Supporting offshore pipeline asset inspection

Creating geophysical north-up and strip charts to inform remedial work planning

Regular condition inspection monitoring is the cornerstone of any asset management strategy. An exposed or free-span pipeline can result in costly breakage. Bathymetric and geophysical surveys are usually undertaken annually in line with monitoring obligations. Such data is then reviewed to inform remedial work planning, and actions taken if issues are found.

An ABPmer client wanted to visualise geophysical survey data collected along an offshore gas pipeline. We were asked to create a series of north-up and strip charts from data gathered within an offshore gas field.

We first imported and displayed the multibeam echosounder bathymetry (depth) data and used this to extract longitudinal profiles of the seabed. Using AutoCAD, a series of strip charts were created at a 1:2500 scale along each pipeline. The charts displayed plan view bathymetric imagery and a seabed profile. Features of interest along the pipe such as exposures, free-spans and engineering features (mattresses, grout bags, crossings and debris, etc) were labelled and overlaid providing a visual summary of the data collected.

All charts were created in AutoCAD software and electronic outputs delivered in DWG and PDF formats.