Luo Y.,Jianshe Beilu Yiduan |
Huang P.,Jianshe Beilu Yiduan |
Li M.,Jianshe Beilu Yiduan |
Ge L.,Jianshe Beilu Yiduan |
Wan W.,Jianshe Beilu Yiduan
Drilling Fluid and Completion Fluid | Year: 2014
When drilled deviated hole in shale formation in many geological structures in Sichuan with water base drilling fluids, borehole instability seemed inevitable. Effort has been made to solve this problem. When using polymer sulfonate drilling fluid to drill deviated hole through the shale formation, wettability reversal, solids particle size distribution control and spurt loss control technologies were combined to control formation instability. Using these technologies, the pores in the near-wellbore formation were instantly plugged, the micro-fractures in the near-wellbore formations were instantly sealed off, and a compact oil-wet mud cake was instantly generated against the newly formed borehole wall. This technology has been used in Gongshan Temple, Lianhua Hill and Zhangjiaping in the drilling of long deviated shale hole sections and fractured sloughing hole sections. Drilling time was saved by 33.5%, rate of penetration increased by 29.4%, rate of hole enlargement decreased by 52.0%, and time spend in reaming decreased by 93.9%.