Offshore staff
ABERDEEN, UK – Well integrity specialist Unity has completed a preparatory P&A project in the North Sea with Petrofac.
Unity deployed its Temporary Abandonment Cap Test Tool (TACTT) to pressure-test two suspended mudline wells for an end-of-life Petrofac was conducting for an unnamed operator.
TACTT is said to be capable of sealing onto any type or size of temporary abandonment (TA) cap fitted to a suspended well. The device will then pressure-test the seal to ensure well containment, and finally test and vent pressure from below the TA cap.
It can also leave a reliable secondary seal in place if required, Unity said.
Aside from providing a fast and mobile method of pressure testing, the company added, the process simplifies and improves safety for the re-entry of suspended wells.
In addition, it allows operators to understand the amount of pressure accumulation below the TA cap since the previous intervention, factoring the information into the operational plan for decommissioning.
For this project, the technology is said to have quickly confirmed zero pressure below the TA caps of the two wells, allowing P&A operations to continue. The TACTT was delivered within a week, returned to Unity after the first well, redressed in three days, then remobilized for the second well.
The TACTT was run on drill pipe from a rig, but it can also be cable deployed for vessel-based P&A activity, with only two engineers required for the operation.
Gary Smart, Unity CEO, said: “Re-entering offshore wells, which may have been suspended for a considerable number of years, is challenging and high risk, particularly as any pressure build up behind the back-pressure valve of the TA caps cannot usually be measured.
“For the first time, there is a safe and efficient method to test and vent these wells prior to re-entry.”
01/15/2020
