Real Time Barrier Verification of a Shallow Set Barrier for Pre-P&A – Long Term Suspension

Challenge

The primary objective of this operation was to execute a Pre-Plug and Abandonment (Pre-P&A) procedure on an aging oil producer well situated in the Norwegian continental shelf. The well had previously undergone temporary P&A measures, involving the placement of both a deep-set plug and a shallow-set plug within the 9 5/8" casing.

The essence of this workover operation was to expand the scope of the temporary P&A by equalizing and subsequently extracting the existing shallow plug from the well. Following this, a new mechanical plug, equipped with an acoustic Pressure/Temperature (P/T) monitoring sensor referred to as the Iconic Digital Transponder (iDT), would be installed.

The incorporation of this monitoring technology was essential to ensure the ongoing integrity of the primary barriers, thereby aligning with industry regulations and ensuring the safe execution of this operation.

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Solution

Monitoring would be provided by connecting a 8.15in OD Iconic Digital Transponder (iDT) to the shallow 9 5/8 casing plug, where the iDT would transmit wireless live well pressure data and deliver recording at the wellhead. Well, is planned to be suspended over a period of 3 years, Iconic will deliver LIVE data T/P trough the whole suspension period.

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Operation

The well was planned to be a producer, but it was temporary P&A after successive attempts to sidetrack without success in 2019 and the deep and shallow barrier  was set. Due to integrity the shallow plug has to be equalized and pulled and replaced with a new 9 5/8 plug. Slot cover removed and the sealing area was inspected. Install and pressure test BOP. Plug and IDT RIH. Pressure test plug. iDT surface monitoring equipment was rigged up – to read out LIVE data from below the plug. The shallow plug was successfully installed with the Iconic pressure- and temperature-sensor hanging below on the plug to monitor the primary barrier. The original plans were to set the plug under the DHSV (4-500m) - to get enough weight in the string to pull off the plug. After discussing with Archer, they have the option to set up the TimeLock plug with a 2.5T collet (Standard 8T collet) Setting depth 80m.

Due to bad weather helicopter was not able to land on platform. Iconic was call on duty and supported the operation from onshore. This is the first IO operation with this client. Planned suspension time of the well is set to 3 years

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Value Created

Iconic iDT system was successfully installed as an IO operation together with the Archer 9 5/8 casing plug. The iDT system will gather valuable data for the client trough the long time suspension period – Monitoring of the primary barrier integrity was required in order to comply with industry’s regulations and execute this operation in a safe manner.

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