Key facts
• Customer: Undisclosed supermajor
• Location: North Sea, UKCS
• Well type: Platform oil well
• Key benefits: PWC® solution reduced dual casing annulus remediation timing from 80 to 3 days
The customer’s challenge
HydraWell supports the operator in question for a plug and abandonment (P&A) campaign that involves a number of wells at approximately 140 metres water depth. The P&A job was conducted from the now shut down production platform, which is relatively small in size.
On previous P&A campaigns in the same field, the operator had used section milling to remediate the dual casing annulus, either section milling one casing at a time or both at the same time. Such P&A jobs had previously taken up to 80 days to complete.
HydraWell was brought on board to try to lower the time and budget required for setting the primary and secondary reservoir abandonment plugs.
The HydraWell solution
HydraWell deployed the PWC® (perforate, wash, cement) technology on the wells, using HydraWell’s HydraHemeraTM tool configured for dual casing applications.
After detailed planning with the operator and all third-party services involved, HydraWell deployed the one-trip PWC® method perforating through both the 7 5/8” and 9 5/8” casings at the same time, before the HydraHemeraTM jetting tool washed and cleaned out debris in the annuli behind the perforated casings.
A combination barrier as defined in the UK abandonment guidelines was then set, tested and approved by the operator.
The result
Rock-to-rock barriers were successfully set and no swarf cuttings were brought topside.
Compared to the operator’s previous P&A jobs, which had taken them up to 80 days to remediate a dual casing annulus when using section milling, it took 3 days to plug a similar well type when using the PWC® method.
