In the UK Sector of the southern North Sea, Spirit Energy continues its plugging, abandonment and decommissioning campaign and here is an awesome photograph of the last step in plugging an offshore well with a sub-sea production system. I urge you to click on the little thingy, upper right to get a better look.
The well has been plugged under strict regulatory oversight; permanent, steel 15K PSI differential plugs have been set in every concentric string of casing followed by massive, thick cement plugs, pretty much top to bottom. The well head assembly is rigged down and set aside.
All those casing strings are cut at the mud line with mechanical or jet cutters then a bell nipple is welded on by divers and a bolted flange to flange cap is placed on the well complete with permanent labeling, location and ID numbers, etc. The WH assembly is then lifted to the surface.
In the photograph above a WH is being pulled to the moon pool below the drill floor where it will be unbolted, lifted above deck and taken back to the beach. I don't know how long this WH was in the water but I suspect a good while. The very top photograph is courtesy Well Safe Solutions, Aberdeen, and is Well Safe Defender plugging and decommissioning rig.
"It's Not Dark Yet, But It's Gettin' There." Bob Dylan
The North Sea oil producing province will celebrate its 60th birthday in 2024; it has given the world so much oil and so much natural gas, from such a harsh environment, requiring the absolute greatest of innovation and engineering skills... every man, woman and child on earth should be proud of the North Sea. It represents the utmost in human spirit and resilience.
She has a number of years in her still, the North Sea, but she is old and tired and good operators are doing what has to be done to properly put her to bed.