Inflow Test Device Enables Barrier Integrity Verification when Traditional Methods Aren’t Feasible
An offshore operator in Western Australia verified a subsea well's barrier using Interwell's ITD and BVS system, overcoming completion integrity issues. The solution enabled accurate, real-time inflow testing without surface manipulation, improving efficiency and ensuring reliable barrier qualification through significant pressure drawdown confirmation.
Year
Region
Challenge
A major offshore operator in Western Australia was conducting a pre-P&A suspension intervention on a subsea well, which required the installation of suspension barriers in the production and annulus bores. Since the liner top couldn’t be tested for integrity, an inflow negative test was necessary to verify the primary barrier set in the production tubing. However, due to a suspected leak in a tubing connection above the production packer, performing the test from surface might not be possible.
Solution
Interwell proposed using a Barrier Verification System (BVS) in combination with an Inflow Test Device (ITD) between Retrievable Bridge Plugs (RBPs) to achieve the barrier verification objectives.
Before the job, volume calculations were conducted to configure the ITD chamber, considering both scenarios of either oil or seawater being trapped between two RBPs (which were set 20 meters apart). After the lower RBP was set, the ITD was deployed in combination with a BVS transmitter suspended below the upper RBP. The ITD was set up at the surface to activate on a time delay.
After setting the upper RBP, the inflow test was monitored from the surface in real-time using an Active E-line BVS receiver, which recorded pressures above and below the upper RBP. A pressure drawdown of 2900 psi was observed between the barriers, and pressures were monitored for an additional three hours to gather sufficient evidence for qualification. The significant pressure drawdown also confirmed that the well fluid present between the barriers during the inflow test was seawater.
Value Created
The combination of the ITD and BVS enabled barrier testing in the direction of flow for integrity qualification, providing a more effective and cost-efficient alternative to traditional methods such as surface pressure manipulation, which was not possible due to completion integrity.
Additionally, the ITD’s capability for variable volume calculations and chamber preparation allowed for precise inflow test setup, optimising job execution and ensuring reliable results.
Key Capabilities
- Inflow test through local pressure manipulation
- Well integrity and barrier verification
- Real-time remote monitoring using surface powered equipment
- Reduces rig time and surface footprint
- Combination of services to minimise intervention runs
