12-hour reinstatement for $20,000/day production well
Platelets® seal 1mm outer annulus to conductor leak
- Client Major Operator
- Leak Location Outer Annulus - Conductor
- Location North Slope, Alaska/li>
- Nominal Bore 9 5/8 inch casing
Challenge
An oil production well was shut-in following the identification of a shallow leak from the outer annulus to the conductor, resulting in annulus fluid discharge to the environment. Costly and time-consuming work would normally be required to excavate and remove the conductor casing in order to patch the leaking casing.
Solution
A set of tailored diagnostic flow tests using Telepath® were carried out to profile the leak, confirming a leak of 1mm equivalent diameter. A solution containing specific Platelets® designed to seal leaks of that size, and to cope with the environmental conditions they would be subjected to in the coming years, was injected into the system via the annular wing valve.
Outcome
Annular pressure rose as soon as the Platelets® reached the leak zone. The operation stopped the annulus to conductor communication and the well passed an MIT at 1,800 psi to reinstate full service qualification. The solution was achieved without having to excavate and remove the surface conductor, or pull the tubing and cut and pull the casing.
The upside
$20,000/day production was regained in twelve hours. A costly excavation workover was avoided and there were no heavy equipment or plant requirements. The well was reinstated by a simpler and much safer process than excavation and was brought back to a serviceable state in a much shorter time frame than a conventional process: twleve hours, compared to six weeks for excavation, the only other alternative approach to repairing the integrity of the well.
