Abstract
An offshore operator in Malaysia detected an unexplained annulus pressure increase after completing a large-bore gas production well. A leak detection tool was run on an electric line tractor and located leaking tubing connections at 333 m and 394 m MD. This led the operator to recomplete the well.
The operator chose to close a fluid loss isolation valve at 1800 m MD. Because an electric line tractor, hydraulic stroking tool, and key tool were already onboard the platform as a contingency to open the valve, this suit of technology was chosen to close the valve.
The toolstring was configured with a 4.625" key pad to fit into the sliding sleeve of the valve and run in the hole. The tractor was activated 146 m above the valve and then driven down to the valve where a depth correlation was made. Then the toolstring was placed with the key extended until it reached the recess area above the shifting profile. The piston of the hydraulic stroker was extended with the key pads expanded and located the shifting profile. Next, the hydraulic stroker was activated to stroke up and thereby closed the ball valve.
The valve was closed in 15 hours from rig up to rig down, including 2 hours of inflow test. This was the first time such a valve has been closed on electric line in Asia Pacific and the operation proved the viability and efficiency of the technology. Importantly, the operator did not kill the well and saved significant costs by cutting the time in half compared to a workover.
This paper will present the learning from the operation while discussing this newly adopted approach and the benefits it offers to the industry.
