TDW ILI Support Services include:
AGM (Above Ground Marker) Site Selection: Careful review of maps and terrain
characteristics to determine factors such as depth of coverage, power line interference,
negative roadway infl uences and accessibility of right-of-way.
GPS Surveying: A process involving global positioning satellites allows highly refi ned AGM placement to within sub-meter accuracy. Precisely established and logged points along a pipeline route enhance tool detection and the accuracy of anomaly locations. TDW also uses a triangulation process to accurately establish GPS coordinates.
AGM Deployment: Prior to launch and deployment, ILI tools and AGMs are
synchronized with exact atomic time. AGMs are then located along the pipeline route
and activated in preparation to detect pig passage utilizing highly reliable Bluetooth®
communications technology.
Pig Tracking and Locating: Following the progression of an ILI tool through a pipeline to confi rm pig passage at each AGM site. In the event that a pig should stop, its location will be determined between the last AGM site passed and the AGM site yet to signal passage.
AGM Retrieval: Picking up all markers after pig passage and documenting the time of
passage at each location.
GPS Data Logging: After ILI inspections, a detailed report is created with the longitude and latitude of AGM locations, which assists in locating specifi c pipeline anomalies with greater accuracy. Surface photos of each site and instructions on how to access specifi ed locations via roads and right-of-way easements are also provided.