BP has still not established what caused the hull of its largest floating oil production vessel to crack in heavy seas west of the Shetlands last week.
The monohull of the floating production storage and offloading vessel (FPSO) on the Schiehallion field was damaged after being struck by a 20m wave at 10pm on 9 November.
Three cracks appeared in the bow section, 15m above the waterline. The largest was about 1m across and 8cm wide.
A spokesman said the damage occurred in 14mm-thick steel plate above the main structure of the hull, which is made from 25mm-thick plate.
The vessel was not producing oil at the time and none of the 75-strong crew were injured, but 30 crew were evacuated as a precaution. ‘It was a bit of a surprise for everyone,’ said the spokesman.
He added that BP had contacted Brown & Root, the engineer and project manager on the Schiehallion development, and Harland & Wolff shipyard in Belfast, which built the vessel.
Eight experts from BP Shipping and the Health & Safety Executive examined the damage and made suggestions on repairs, which should be finished this week.