Unpiggable

Pipelines are usually inspected using “free swimming” inspection tools propelled by the product medium itself. The downside of such inspections is the pipeline operating parameters (production, flows & pressures) and complex launch and receiving requirements. Romstar offers unpiggable solutions as an alternative.

On-line inspection tools attached to an umbilical can be used to transfer the inspection data to storage for later processing and analysis. Umbilical tools can also be propelled into the pipeline by a fluid, pulled into the pipeline with a cable or crawl into the pipeline either by driven wheels or pneumatically in a similar way as a caterpillar. The maximum distance, which can be inspected with umbilical tools, is dependent on the cable type and length and on the number of bends in the line. The limiting factor is not the bend radius, but the cumulative number of bends the tool has to pass. An advantage of umbilical tools is the real-time information on the measurements, which are available during the inspection. This enables a direct assessment of detected features and the possibility to stop and re-inspect certain sections of the pipeline.

Alternatively, the combination of “free swimming” combined with cabled or umbilical pigging can also be deployed internally in pipelines. Such inspections tools have the ability to:

• Inspect pipeline lengths up to 12km in one run.
• Negotiate unlimited number of bends.
• Tool travel in both directions.
• Inspect multiple diameters in one run.
• Provide ultrasonic measurement online.
• All data stored on tape which allows for detailed processing.