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Sahara leak detection tool used for speed, accuracy and on-the-spot results

Sahara platform inside a pipe filled with water

For more than 15 years, water operators have relied on the Sahara® leak detection platform for speed, accuracy and on-the-spot results required for inspection of complex pipeline networks typically found in urban environments.

The Sahara in-line tethered tool can assess pipelines 6 inches and larger, while the line remains in service. Because it’s tethered, an operator has complete control, and can closely examine events of interest, such as a leaks, air pockets, and visual anomalies.

The tool is propelled by the product flow, requiring a flow velocity of only one foot per second, and is able to navigate in flows up to ten feet per second, with no disruption to service.

Sahara device

Sahara tool can be inserted into almost any existing tap 2 inches and greater

To insert the tool into an active pipeline, almost any tap 2 inches and greater can be used. As the tool enters the pipe, a small parachute or drogue is inflated by the flow velocity of the water. The parachute pulls the tool through the pipe, with the probe lighting the way with its onboard LED lighting system, highlighting any visual defects in the pipeline.

If the Sahara tool encounters any acoustic events—such as a leak—the operator can stop the tool at the exact point of the leak. At the same time, an above-ground operator locates the sensor, marking the exact leak location within plus or minus 18 inches (0.5 meter). This enables users to know in real time where the leaks are, and where repairs are needed.

Worker finding the exact spot for a issue reported during the inspection

Detects up to 4 times as many leaks as trunk main correlators

The tool can detect up to four times as many leaks as trunk main correlators because the acoustic sensor is brought right to the leak – pinholes, cracks, joint leaks – Sahara can detetct virtually any type of leak. In addition, the tool can detect air pockets in the pipeline, both visually and acoustically.

As the Sahara tool inspects the pipeline, it may encounter valves that connect a high pressure zone to a low pressure zone, and if one of those valves is not fully closed, Sahara can also detect the lack of isolation between zones during the inspection.

Visual anomalies detected during inspection

Detect leaks, air pockets and visual anomalies while mapping the pipeline path

The tool can navigate single bends without issue, but is limited up to 270 cumulative degrees of bends in a single survey.

While the video and acoustic inspection is taking place, the tool can also be used to map the pipeline path, providing a clear plan view of the pipeline with sub-meter accuracy. The beauty of the Sahara tethered platform is that it can provide a variety of pipeline condition information in real time, with no disruption to service, on all pipe types.

Houston Skyline

Enwave Houston deploys Sahara tool to quickly locate leak in chilled water line

In December 2015, Pure Technologies (Pure) was retained by Boyer Inc. to perform a Sahara inspection on a 24-inch Chilled Water Supply pipeline (CWS) and on a 24-inch Chilled Water Return pipeline (CWR) operated by Enwave Houston.

The purpose of the inspection was to locate a suspected leak on one of the dual lines that run parallel along the downtown core. Large cities often operate central chilled water plants to cool water that is then sold to building owners for use in air conditioning.

Tools on the surface before starting with the inspection

Insertions completed at night, with no traffic disruption or chilled water disruption

Boyer proposed two separate Sahara insertions during the planning phase. Pure completed both insertions at night over a two-day period for a total of 795 feet of pipeline inspected, with no traffic disruption or chilled water disruption. Acoustic data was collected and recorded during the inspections as the Sahara sensor traversed the main. The data was evaluated on site in real time to identify events associated with leaks and pockets of trapped air.

During the inspections, one (1) leak and zero (0) air pockets were detected. The leak was located 144 feet downstream from the insertion point with sub-meter accuracy. This allowed a pinpoint excavation to be made for repairs, minimizing disruption to downtown Houston traffic, and minimizing the contractor`s cost of excavation and road restoration.

Once again, the Sahara tool proved its worth.

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