HOUSTON – An offshore operator recently had success with a complex drill-in with liner through the cap rock into the top of a high-pressure, high temperature (HPHT) well in a recent North Sea operation, says Baker Hughes.
Once at TD, the drill-in liner was successfully cemented on bottom to isolate the cap rock. This was required because of the high pressure differential between the cap rock and reservoir. The EZLine system prevented the possibility of large drilling fluid losses entering the reservoir, says Baker Hughes.
A modified Hughes Christensen PDC bit drilled the 7-3/8" intermediate section 30 m (98 ft) to TD in 22.5 drilling hours. Subsequently, a specially commissioned application-specific Quantec 5-5/8” drill-out PDC bit drilled 123 m (403 ft) of cement, landing collar, float shoe, and EZcase bit in 24 hours.
The bit went on to drill 167 m (548 ft) of the reservoir in 57 hours to TD and was rerun for a wiper trip after logging, says Baker Hughes. The excellent borehole quality enabled openhole logging without difficulty.