Published: 01/01/2007
Published: 01/01/2007
An operator’s high-profile completions project was its first development project in a particular deepwater region and its entry into production for a particular country. Several deepwater, subsea, high-angle wells were in approximately 1,400 m [4,593 ft] of water. In this challenging environment, the operator needed to isolate the formation and gravel pack the reservoir as efficiently and cost effectively as possible.
The Schlumberger FIV Formation Isolation Valve was installed below the gravel-pack packer. When the gravel packing was finished, the FIV valve was closed, allowing the gravel-pack tools to be safely retrieved and the formation to be isolated for installation of the upper completion. An underbalanced pressure differential was then created above the FIV tool. The valve was reopened using the Trip-Saver one-time opening tool, and the well was placed on production.
The TIVF isolation valve with flapper was then used to allow testing of the tubing during installation of the upper completion. The valve was run in the closed position, allowing the tubing to autofill. When the TIVF valve was in place, the tubing pressure was cycled to enable the production packer to be set. After the packer was set, the TIVF valve could be further cycled to actuate the Trip Saver mechanism and open the valve. The use of this valve eliminated approximately 6 h of intervention per well.
Business objectives required that the completion be installed before subsea Christmas trees were available. A valve was needed to provide an additional barrier below the tubing hanger. The SFIV surface-controlled FIV valve was used to suspend the well after the upper completion was installed. The use of this valve eliminated 1 to 2 rig days per Christmas tree installation and saved the operator an estimated USD 1 million per well.
The final three wells, with their high productivity indexes (PIs), were among the operator’s highest-producing wells anywhere in the world, and—along with the zero skins—exceeded the operator’s targets. These outstanding results were attributable in part to a combination of the FIV valve and the fluid systems and gravel-pack technologies used in this completion project and were achieved with no accidents, no harm to personnel, and no damage to the environment. The collaborative operation helped the operator reach its intended target reservoirs, with reservoir performance exceeding expectations.
The final three wells, with their high PIs, were among the operator’s highest- producing wells anywhere in the world, and—along with the zero skins—exceeded the operator’s targets.
Challenge: Gravel pack the reservoir economically in a challenging deepwater well without intervention and provide barrier for well suspension
Solution: Install three Schlumberger isolation valves:Results: Saved the operator an estimated USD 1 million per well by eliminating the need for intervention
