Cased-Hole Logging Products – Well Integrity
WLD-Well Leak Detector
 The Well Leak Detector (WLD), a cased-hole logging tool developed by TecWel, detects and locates leakage in a wellbore with a depth accuracy of a few inches. Any oil, gas, water or multiphase fluid leak can be detected with rates from as small as 0.02 liter/min (or 0.004 GPM) and upwards. Also multiple leaks in a wellbore can be detected.
With the WLD TecWel is able to detect any leak in:
- The production packer
- The expansion joint, or any other subassembly
- The tubing
- The Downhole Safety Valve - DHSV
- The control line to the DHSV
- Any of the casings in the well
- The wellhead
Specifications for using the tool:
The WLD is deployed inside the tubing, even when logging to identify a casing leak. While logging with the WLD, the only thing that the WLD needs is an active leak, and the subjection of the failing barrier to a ∆P (differential pressure) causing a flow of fluids through the leak point(s) (i.e. generating an active leak). While logging with a line speed from 3 to10 m/min (10 to 30 ft/min) to locate a leak, the well could be shut in, producing or injecting into the reservoir and still the WLD can find the leak point. The WLD can also been run inside a casing (i.e. no tubing installed in the well).
The standard WLD Tool String is configured like this:
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The WLD Technical Specification:
(Download the technical specification sheet in PDF format)
| WLD Information |
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Digital Signal processing (DSP) |
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Real time measurement |
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| Sensitive ultrasonic passive sensors |
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| Leaking fluids |
Oil, water, gas, mud, brine or multiphase |
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| WLD Requirements |
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| Differential pressure and an active leak i |
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| Required voltage |
18 V ± 5 V |
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| WLD Specification |
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| Leakage location accuracy |
± 0.1 metre (3.9 inches) |
| Min. detectable leak rate for liquids |
0.02 litre/minute (0.0052 gal/min.) |
Min. detectable leak rate for |
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| gas under downhole conditions |
0.02 litre/minute (0.0052 gal/min.) |
| Min. required ΔP across the leak point |
> 3 bar (45 psi) |
| Repeatability |
1 % |
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| Deployment |
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Electric line (mono conductor) |
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Well tractor |
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Coiled tubing |
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| Depth correlation |
CCL (GR is an option) |
| Maximum line speed while logging |
10 m/min. (30 ft/min) |
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| Tool String Data |
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Maximum tool OD |
1/11/16” (42.86 mm) |
| Length |
2.05 ft (625 mm) |
| Weight |
8.6 lb (3.9 kg) |
| Pressure rating |
15,000 psi (1034 bar) |
| Temperature rating |
302 °F (150 °C) |
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(Higher temperatures on request) |
| Telemetry |
Sondex Ultrawire |
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Material quality H2S & CO2 resistant |
i An active leak is a flow of fluid through a leak path where the flow is caused by a differential pressure. |
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