The objective of the project is to design a tender to assist a TLP (Tensioned Leg Platform) for the drilling of 24
wells to 8500m max in 800m of water. DIETSWELL designed a STAD (Semisubmersible Tender Assisted
Drilling) to install the Drilling Equipment Set on the TLP while all other drilling equipment would remain on the

Simultaneous drilling and coiled tubing operations were a driver to the design. The entire DES (Drilling Equipment
Set) has been designed so that coiled tubing injector head can be installed on BOP floor and both operations can
be performed without interfering with each other. In order to accommodate the 13m height coiled tubing injector
head, the drill floor level was set at 45m above sea level. The main crane is designed to install the DES. The
auxiliary crane is designed for usual daily operations.



Structure typeSemisubmersible tender assisted drilling (STAD)
Rig LocationCongo
ClientTotal E&P Congo
Project PhasePre FEED
Type of ContractDesign competition
Contract Start / FinishMarch-August 2011
Man-hours8000 hours


Rated Drilling Depth8500m
Water Depth800m – Max: 1500m
Overhaul (L x l x h)82,5m x 57m x 26,5m
Power Generation4 x Caterpillar C175-16, 2590HP
DrawworksNOV ADS-30D, 3000HP
Top DriveNOV 8SA
Derrick / MastBootstrap Mast LEE C MOORE xS-Mast, 49m x 10m x 10m, 590mT (1300000lbs)
Mud pumps3 x National 14P-220, 2200HP 7500PSI
Storage capacities

– Mud Tank: 1400m3

– 8000 Sacks

– Bulk Mud/Cement: 480m3

– Base Oil: 810m3

– Drillwater: 2520m3

– Freshwater: 810m3

– Fuel: 2540m3

– Ballast: 5940m3

Well control systemBOP 18 3/4” 5000PSI
Accommodation158 persons