Subsea drilling secures Rankin caissons

摘要

Eight caissons of varying diameters on the North Rankin A platform on the Australian North West Shelf have been successfully fitted with arrester bars,with the help of a specialist subsea caisson drilling machine purpose-developed by engineering technologies and services company Furmanite Australia for operator Woodside Energy The arrestor bars were fitted earlier this year as a measure to prevent the 8t caisson pumps from falling to the seabed(some 150m below)in the event of a failure of the pump or its pipework.In order to fit the arrestor bars,a total of sixteen 190mm holes had to be drilled in the caissons at depths of 8m below sea level.The eight caissons being modified were of three different outside diameters;750mm,900mm and 1012mm.