|
Methodology:
We utilize an advanced, computerized system capable of hearing the noise made by the pressure differential of the flow moving around the pig, and then pinpointing the location of the origin of the noise. In order to do this, the pipeline may have to be exposed to the bare steel wall, at certain intervals (typically determined by size and pressure), in order for us to magnetically attach our sensors directly to the pipe. These Field Sensor Units communicate via radio to the computer which analyzes the acoustic data, and pinpoints the location of the pig.
Examples.
During a project for Marathon-Ashland Pipeline and C-Pig in Woodhaven, MI, we were able to use our 60" Probe Bar to make a safe contact with the pipe, magnetically attach our sensors to the probe bar and made a successful locate with about a 3,000 ft. distance between the two points. Although the system's calculation of the location was 19 Ft. away from the pig's exact location, we were much better than their original estimated location - over 4 miles away.
On other locates, we were able to make direct contact with the pipe (vs. the probe bars), and were only 6" off from the exact location of the pig.
One of our more challenging locates was performed for LOOP, LLC in Port Fourchon, LA (as a subcontractor to PEI) on a submerged 4" diesel line supplying fuel to an off-shore platform. Sensor distance (span) was 11,532 ft, and the Enduro gauging pig was located within 3 seconds. Of course, it took the rest of the day to verify, with close interval surveying (and after LOOP recovered from the initial "shock & awe"). Hebert was the survey contractor on the project. See the picture.
Our summation is this:
We can utilize the probe bar approach to eliminate excessive excavation, thus increasing the amount of pipeline we can survey in a given timeframe.
We can expect up to a 3% error at a 3,000+ ft. distance due to the vibration of the pipeline, probes, distance anomalies, minimum pipeline contact, etc.
Placement of the sensors directly on the pipe increases the accuracy.
The location of the pig can typically be confirmed non-intrusively with the additional use of ground microphone and magnetic locating technology. And,
Our methodology works, and is proving to be a superior stuck-pig locating system vs. other methods (if there are others.)
Don't wait. Stop paying "Pig Rental".
Contact us, TODAY!
|
|
