BiSN, a supplier of downhole sealing solutions and technology, has caught up with representatives from Aker BP regarding the successful plug and abandonment campaign conducted in the Valhall oilfield in 2020.
Aker BP needed to safely P&A 30 wells in the Valhall field in the North Sea and partnered with BiSN to deploy Wel-lok technology to create safe and cost-efficient Wel-lok plugs. After extensive testing conducted over the past two years, it has been shown that not only did this provide a permanent plug and abandonment solution, it allowed for new wells to be drilled and operated safely for the next 30 years.
“As part of the success story, we are monitoring the same wells today and we’re proud to say that out of the 30 wells today there is no leakage,” said Kjetil Vadset, Senior Drilling Engineer, Aker BP.
For two years prior to commencing the campaign in 2020, Aker BP and BiSN carried out a joint testing programme at BiSN’s Houston location to ensure Wel-lok technology was the safest, most cost-effective option. As a result of completing this rigorous testing programme, BiSN Wel-lok technology received acknowledgement of consent for use, including DNV-GL verification and PSA (NORSOK) evaluation of bismuth.
“Qualifying Wel-lok technology for use in the North Sea and securing a long term partnership with Aker BP were two major priorities for BiSN at the time,” said Paul Carragher, Founder and CEO of BiSN. “We are looking forward to continuing to develop a one team relationship with Aker BP on their forthcoming P&A campaigns.”
By implementing Wel-lok technology over traditional cement, it is estimated that the campaign saved approximately three months of rig time, or approximately US$2mn per well.
As part of the campaign, BiSN delivered the largest bismuth plug ever deployed to date. Produced at BiSN’s UK facility, the tool weighed in at 33,191 lbs and sealed up to 30 inches in the wellbore.
“We're very proud. The operation has gone beyond expectations. We planned and hoped for 72 hours per installation. We're down to 33 hours per installation just now,” said Vadset.
