By OGJ editors
HOUSTON, May 21 -- Transocean Inc. claimed its GSF Rig 127 jack up drilled a record length extended reach well off Qatar for Maersk Oil Qatar AS.
GSF Rig 127 drilled Well BD-04a to 40,320 ft measured depth with a 35,770-ft lateral section in 36 days in Al-Shaheen field. The record of 7.6 miles also is the first well in the history of offshore drilling to exceed 40,000 ft, Transocean claimed.
The well, in 200 ft of water in the Perisn Gulf, bottomed at a true vertical depth of 3,500 ft subsea. Inclination of its horizontal section was 89° to just over 91°, Maersk Oil Qatar said.
The extended-reach portion surpassed by 2,000 ft the previous world extended-reach record of 38,322 ft MD set by Parker Drilling Co. working for ExxonMobil Corp. The ExxonMobil well was drilled by a land rig at Sakhalin-1 under the Sea of Okhotsk in Far East Russia to a target area in Chayvo field 7 miles offshore (OGJ, Feb. 18, 2008, p. 33). That well was drilled with the custom-designed Yastreb land rig.
Transocean said its GSF Rig 127 crew dealt with high torque in the well's extended reach section. The crew used extensive deck-management planning and a supply boat to hold additional drill pipe so that the rig stayed within its variable deck-load rating.
OGJ archives indicate that Well DB-04a may be the world's longest well bore. The former Soviet Union claimed it drilled the vertical SG-3 research hole well to 40,228 ft in the 1970s-90s on the Kola Peninsula near the Norwegian border west of Murmansk (OGJ, Dec. 7, 1992, p. 32).