DECOMMISSIONING
One-stop decom solution
Flexible approach enables operator to improve efficiencies
C
omprehensive and bespoke services have recently helped an operator plug and abandon its wells in the southern North Sea. Te field had been producing
natural gas for over 40 years. At its peak, it supplied around 10% of the UK’s gas requirements. In the 1990s, an infield drilling programme and new production technologies revitalised the field. Nevertheless, many older wells had reached the end of their operational lives, prompting the beginning of a multi-year well abandonment campaign. Te age of the wells is challenging.
Many of the well interfaces are obsolete, which means that some well intervention equipment needed to be developed specifically for the campaign. Te decommissioning team from Claxton worked closely with the operator to understand the project requirements. From the outset, it was clear that Claxton’s Sabre subsea abrasive cutting system would be a vital part of any campaign to cut and recover the wells. However, Sabre’s growing popularity meant that the units were in high demand, with some backlogs, so were not immediately available.
RAPID REACTION Claxton promptly manufactured a new Sabre unit with a reduced footprint designed specifically for the client’s campaign. Tis unit was deployed in December 2013 and has since been in continuous service. Te system is reliable, flexible and easily moved between platforms and vessels. It also has a low environment impact, using only naturally occurring garnet minerals, air and water in its transonic-speed abrasive jet, which is capable of severing wells with multiple cemented casings. Te well-dewatering packer was also upgraded.
52
www.engineerlive.com
A new Sabre system was manufactured specifically for a recent decom project
Te project scope also includes supply of on-site machinery, surface riser systems, bespoke interfaces, bandsaws and drills to cut the recovered sections, and debris caps and slings for safe multi-string backload. Te operator is using Claxton’s equipment and services to improve its decommissioning efficiency and capacity, which helps to reduce costs and release
resources for other projects. Te company was able to take advantage of Claxton’s extensive riser inventory to get what it needed quickly. Te firm’s on-site machinery and skilled engineers were also able to swiftly deliver bespoke equipment. Robert Leggett, decommissioning
product leader at Claxton, says, “We really wanted to work with the operator on its campaign. I am delighted that we were able to react quickly, including manufacturing a Sabre system specifically for the project. It is great to see this and our casing-recovery system in two years’ continuous service and with more work to do.
“Te ability of our multi-skilled team Older wells can require bespoke tools
to move from one operation to another without the need for continuous crew changes was particularly valued. We are now collaborating with the client on new systems and methods of work to further increase operational efficiency. l
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56
