Case study LeakPoint 4

Leak at GLV dummy. The peak indicates turbulent flow in the vicinity of the tool, revealing the exact depth of the leak point.

Retrieved GLV dummy (bottom) with its damaged seal. A healthy GLV replacement is shown (top).

Region: North Sea, Norway
Well type: Newly completed producer

Challenge
A failed pressure test following the installation of a new completion in a North Sea oil producer led to the discovery of a 2 l/min. leak. The leak presented the operator with a diffi cult choice: undertake a lengthy troubleshooting process or
pull the completion. Further concern about wash-out damage to completion equipment made a quick solution imperative. Several leak sources were suspected. These included 3 gas lift valve (GLV) dummies and a chemical injection valve dummy. The completion also included a new packer, which had not been set, and a lower-set production packer. A plug at 3,827m limited the possibility of deeper leak points.

Solution
A LeakPoint survey was specifi ed and completed in under 10 hours. This precisely located a leak in the upper GLV dummy, which was retrieved and found to be damaged.

Case benefits

• Rapid, accurate leak location enabled precise diagnosis and remediation
• Portable diagnostic system enabled fast mobilisation and deployment
• Rapid diagnosis avoided risk of completion wash-out damage
• Customer stated intervention and production savings amounted to millions of dollars

Key capabilities

• Fast, highly accurate location of single or multiple leaks
• Locates even complex leaks in A, B & C annuli through tubing
• Sensitive to a wide range of leak rates: 0.02 to >5,000 l/min.
• Clear, unambiguous log response
• Proven effectiveness. Pinpointed leaks in >90% of wells surveyed
• Confidently select and target the most effective remedial intervention

Results
The LeakPoint survey provided the precise location of a diffi cult-to-pinpoint and potentially expensive leak. The survey also verifi ed the integrity of the other completion components within the well. The failed GLV dummy was replaced, a pressure test was performed and no further leakage was found. The customer stated that LeakPoint technology had helped to avoid lost production, re-completion and further intervention costs, saving the operator millions of dollars.

Typical applications

• Locating leaks in tubing, casing and completion components
• Pre-workover diagnostics
• Post-remediation validation
• Pre-abandonment survey