Claxton, an Acteon company, has improved the technological advantage of its Suspended Well Abandonment Tool (SWATTM) by developing an extension module. In turn, this enables Claxton and Acteon sister company, Offshore Installation Services Ltd (OIS), to set deeper environmental and intermediate barriers.
Neil Watson, SWAT product leader, Claxton, said, “SWAT holds the Queen’s Award for Innovation in the UK, and the Petroleum Institute Platinum Award for Innovation. It is the first tool of its type, and is provided by Claxton in co-operation with OIS. In combining our proven SWAT tool with the new extension module, we have significantly increased the range of wells that can be abandoned using SWAT. By providing our customers with more opportunities to opt for this rigless method, we enable them to reduce their well abandonment costs considerably.”
The existing multi-award winning SWAT tool is deployed from a vessel of opportunity through the moonpool, eliminating the need for a drilling rig. It is positioned on the wellhead and then used to perform casing perforation, recovery of drilling mud and placement of the required cement barriers in the well.
SWAT utilises the extension module to enable cement to be positioned even deeper within the well. A wiper plug is positioned before and after the cement column, which ensures that the wellbore is cleaned ahead of the cement. The lower plug forms a base for the column and slurry is uncontaminated when it enters the annulus. The cement is then displaced to the required depth in the well. In OIS’s most recent well abandonment campaign, the depth was 2400 feet below mudline. This added depth capability significantly enhances well decommissioning capacity; previously, the SWAT tool was limited to environmental barriers up to 600 feet below mudline, which limited the wells eligible for abandonment with SWAT.