Buried Pipeline
& Utility Locating Services

Stress Concentration Tomography

3-D Line Locating Ltd.; along with Speir Hunter Ltd offers a non-invasive pipeline inspection service based on Stress Concentration Tomography.

SCT is a passive magnetic sensing tool that collects the magnetic data of a target pipeline and then analyzes it for self magnetic-flux leakages in the pipeline wall, which are know as Stress Concentration Zones(SCZs). Using this stress-profile information, integrity managers can make informed decisions regarding the safe operation of their pipelines.

What is the Process Workflow?

Inspection is usually conducted by a two man team but in some circumstances it is possible for one man to conduct an inspection alone. Depending upon terrain it is usually possible for a single two-man team to inspect lO kms of pipeline in one working day.

The client expresses serious interest in contracting our services. We request technical data of the pipeline information that includes pipeline diameter, wall thickness, current and historically high operating pressure as well as the material grade of the pipeline. These variables are then used to calculate whether or not the pipeline is suitable for SCT inspection.

Assessment of the pipeline route is carried out to determine terrain and potential obstacles for proposed field inspection.

The pipeline route is marked out. and above ground obstacles such as parked cars are removed from the pipeline route. Field workers assess the pipeline route for above-ground objects that could cause magnetic interference. They are then moved and if this is not possible, logged into our mapping system to identify any potential false positives at a later stage in analysis. Once the pipeline route is marked out and is safe and clear, field workers collect magnetic data of the pipeline by walking over the survey route carrying the Uniscan scanner.

Once fieldwork is finished, the magnetic and surface feature data are uploaded to a computer and sent to our data analysis centre in the UK. Depending on the requirements of the client, preliminary results can be delivered prior to demobilization.

Following the delivery of preliminary results, we send our clients a final integrity report that contains detailed information that the client can use to make informed decisions regarding the safe operation of the pipeline, and to identify locations that may need further investigation or repair.

What are the benefits?

– SCT reports the presence of all defects in any orientation causing stress magnetisation in the pipeline wall. This includes corrosion, cracks, dents, sagging and twisting.

– SCT requires no pre-inspection preparation of the pipeline or modification to operating parameters. Neither us excavation for contact NDT required in the process workflow. Consequently there are no hidden costs to drive up the quoted cost of inspection.

– SCT can be used in conjunction with ILI for monitoring the development of stress caused by defects within specific sections of a long pipeline. Through the periodic measurement of defect growth, excavations and repairs can be scheduled more efficiently and disruption to service and revenue dramatically reduced.

– SCT can be used in conjunction with other non-invasive methods such as DCVG and CIPS as a solution to confirm if damage to the coating and/or current leakage has led to damage to the pipe wall.

– SCT can be used to map the pipeline route to sub metre accuracy, accurately identify the location of casings, pipeline diameter changes and to distinguish between longitudinal weld and seamless construction.

Contact us to receive more information or to book your Presentation on this new technology.

Download our brochures to learn more about this service

3-D Line Locating Ltd is a privately owned Buried Pipeline and Utility Locating, Ground Disturbance Management and SCT Services company. For over 20 years, we have been at the forefront of the Damage Prevention industry in Western Canada. Although the industry has changed significantly over the last 20 years, we have been very fortunate to have been at the leading edge of the evolution and still maintain the highest levels of quality, accuracy, consistency and customer satisfaction in our industry.

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