1214WAB® providing a SCP barrier and foundation for P&A cement plugs
- Well type Appraisal
- Reservoir type Sandstone
- WCS products 1214WAB, 812WAB & 6WAB
- V0 1214WAB whitin 13 3/8” casing Enabled client to verify B annulus barrier
- Rapid set V0 WAB LH'S added value Via no requirement for set down weight to seal
- Extensive wab portfolio enabled Extended reservoir contact via 6WAB range
- Capex effective p&a Using V0 1214WAB as base for reduced risk P&A
- Location Norway
An IOC in Norway had an appraisal well application that required a number of solutions, to allow them to construct and complete the well to their high standards.
The list of requirements included a ‘verifiable’ V0 B annulus barrier, a rapid set, horizontal liner hanger for 2 x distinct casing architectures, and also a product that would act as the foundation for placement of P&A cement plugs for abandonment.
During the well construction phase of the well, one 1214WAB was incorporated to and deployed with the 9 5/8" casing, and positioned to set within the 13 3/8" casing. Once at TD, primary cement operations were conducted, and at the conclusion, the 1214WAB was fully set, cement less, within the 13 3/8" casing against the bumped plug.
Challenging cement operations in the 12 ¼” hole due to potential weak formations and high ECD based the rational for the placement of the 1214WAB within the 13 3/8". Once set, the 1214WAB was then tested via applying pressure to the B annulus to FIT + 70 bar confirm Welltec Annular Barrier (WAB) sealing and providing barrier verification.
The WAB was positioned close to the 13 3/8” shoe, to form part of the barrier envelope.
Exposed formations below the 13 3/8” csg shoe increased the risk of gas migrating and resulting in a gas below well head causes problems during PP&A. IS0 14310 V0 leak rate qualification of the WAB permitted installation without dispensation from the authorities. Next step was to drill out across the reservoir section to 8 1/2" open hole.
Primary & contingency liner
The client was unable to reach TD with 8 1/2" section and therefore reverted to contingency operations utilizing the 812WAB & 6WAB as horizontal liner hangers. 812WAB LH was deployed with a 7" liner and once at TD, an engineered cementing operation was conducted to focus purely on 7" shoe integrity, with the WAB being rotated throughout cementing operation. The 812WAB LH was then hydraulically set within the 9 5/8" shoe, with no weight down required to affect a seal.
All pressure was then bleed off the pressure and verification that the WAB LH is set via pull/slacking off weight on the liner top. The remainder of the reservoir section was then drilled out to 6" and a 6WAB LH was deployed with a 4 1/2" cement-less liner, as above.
Plug & abandonment
A 1214WAB was run for the provision of two distinct solutions within this one application:
1. Ensuring no SCP within the B annulus and as a base
2. As a future base for cement during well abandonment
After a successful well test, a bridge plug was installed inside the 9 5/8” casing just below the WAB depth.
The 9 5/8” casing was then cut and the bridge plug and WAB were tested to 70 bar above 13 3/8” LOT.
Cement was pumped to provide the necessary seal integrity to met the regulatory requirements for well abandonment.
Verified B annulus barrier against SCP reduced complexity, gas tight, rapid set horizontal liner hangers for both primary and contingency liners.
CAPEX effective, reduced risk P&A operations.
Enhanced well integrity and extended reservoir contact via IS0 14310 V0 rated WAB portfolio.