Drilling Technology for Ultra-Deep Directional Wells in the Halahatang Area
In order to solve the technical problems that include slow buildup rate and hard well trajectory control in ultra-deep directional drilling in the Halahatang Area of the Tarim Oilfield, we investigated well trajectory control and ROP-increasing technologies for ultra-deep wells. By analyzing difficulties in ultra-deep directional drilling technology, and studying the buildup section trajectory control and the ROP-increasing technology, a technical program was developed. The program tested the PowerDrive Archer rotary steerable system (RSS) in the buildup section of ϕ241. 3 mm hole in ultra-deep directional well for the first time in this area. A motor with medium to low RPM and high power was selected, and combined with anti-shock and anti-abrasion 6-blade PDC bit and high temperature resistant MWD instrument in BHA to control the hole trajectory and raise ROP in ϕ171. 5 mm inclination holdup section. By selecting a drilling fluid system that prevents lost circulation and well kick, and blocks the effects of sulfur and high temperature, safe operation in ultra-deep directional well was guaranteed. Field tests were conducted in four ultra-deep directional wells in the Halahatang Area, the average ROP in inclined section was increased by 13. 53%, the average directional drilling period was shortened by 38. 58%. The composite technology based on the operability in build-up and hold-up sections can be used as a reference for trajectory control and ROP increase in ultra-deep directional wells of the Halahatang Area in the Tarim Oilfield.
AAPG Datapages/Search and Discovery Article #130003© Petroleum Drilling Techniques, Issue 4, 2018