Recovery of drilling fluid circulation and placement of environmental barrier using SWAT™

The problem

A contractor of a North Sea operator contacted Claxton to devise a plug and abandonment solution for a subsea well on a field located in the northern North Sea in the East Shetland Basin on the UK Continental Shelf. The requirement was for circulation and recovery of drilling fluid from the wellbore (Cat 2.1) and 9.5/8” x 13.3/8” annulus and placement of a 100ft environmental cement barrier. Claxton was contracted to provide the full back deck service (SWAT™ suspended well abandonment tool, perforation and cementation) for the first time direct to the vessel operator.

The solution

Proven across over 120 North Sea wells, Claxton’s suspended well abandonment tool, SWAT™, was immediately earmarked for the job. The tool can rapidly perforate, circulate and place the required cement barriers in the well annuli through a wellhead during subsea well abandonment operations.

Claxton provided SWAT with ancillary equipment and support services to undertake the subsea well plug and abandonment work scope. Claxton project managed the complete SWAT package, including the perforation and cementing operation, and formed a strong supply chain link with the contractor Rever Offshore and other partnerships to deliver the complete solution to the end client.

the result

The offshore phase went smoothly and was completed in one week. The operation resulted in the successful placement of a 100ft environmental cement barrier in the well bore and annulus.

Both Rever and the end client were impressed with the professionalism of the team and the outcome.

Scott Cormack, Rever Offshore contract project manager commented: “We are really happy with the SWAT job and appreciate the team’s efforts to get the operation executed safely and successfully.”

This project was a turning point for Claxton and the SWAT system offering, providing a new route to market for the tool.

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