XYZ Mapping

XYZ Mapping

High resolution XYZ mapping technology from TDW pairs global positioning system (GPS) coordinates at above-ground locations with inertial mapping. The result: highly accurate data to support your pipeline integrity program.

This system provides operators with a detailed map of key pipeline features, including:

  • Girth welds
  • Valves
  • Fittings
  • Anomalies

XYZ mapping technology also allows you to monitor pipeline displacement and calculate bending strain. Additionally, if you need to conduct an excavation, the system will guide you to the right spot – eliminating the time and expense of “walking the pipeline.”

Best used for: gas and liquid pipeline systems; the technology is scaled for pipelines from 6 inches through 48 inches in diameter

Key features:

  • Provides sub-meter GPS coordinates for an entire pipeline.
  • Technology reveals the precise centerline trajectory of pipelines in latitude, longitude, and elevation.
  • Assists with identifying bending strain.


  • What kinds of inline inspection tools can be paired with this technology? The XYZ mapping technology can be paired with our deformation (DEF) tools to inspect pipeline geometry. Operators also opt to combine the mapping solution with magnetic flux leakage (MFL) technology for metal loss inspections in small-diameter liquid lines; with gas magnetic flux leakage (GMFL) for metal loss inspections in natural gas pipelines; and with the Multiple Dataset (MDS) platform during comprehensive assessments for multiple threats.
  • How close do control points need to be spaced? Surveyed control point locations must be spaced at intervals that allow no more than 35 to 45 minutes of tool time to accrue in between points. If the inspection vehicle maintains a consistent speed, surveyed intervals may be a maximum distance of 3 km (1.9 mi).
  • Are there any control point locations that are not recommended and/or negatively impact accuracy of the above-ground survey results?Yes:
    • Downstream of any combination of fittings or heavy wall pipe that could cause the inspection tool to surge as it exits the section. Detecting vehicle passage during a surge is much less reliable than at steady speeds.
    • Within 3 meters (9.8 feet) of a casing end or directly over a casing. Casings cause distortion in above ground marker (AGM) signals, making passage time difficult to determine.
    • Near cathodic protection transformers, pumping stations, generators, high voltage power lines, or any other known source of electrical noise that might interfere with the AGMs.
    • Areas with very weak GPS signal strength due to poor sky visibility.