| 摘要 |
FIELD: oil and gas production. ^ SUBSTANCE: method envisages first revealing intervals in boreholes of oil deposit under development, which are composed of insecure clay rocks, for example shale. Then follows preparation of drilling fluid by mixing polymer, salt, and water taking into consideration osmotic pressure of formation water (Pfw) in interval to be exposed, hydrostatic pressure of drilling fluid coupled with pressure loss in hole annuity (Phyd), and formation pressure (Pf). Osmotic pressure of drilling fluid (Pdf) is adjusted by adding salt in such amount that it satisfies equation: Pdf = (Pfw+Phyd-Pf)+(2-4) (MPa). ^ EFFECT: ensured osmotic drainage of bored intervals of insecure clay rocks without loss in mechanical properties thereof. ^ 1 dwg, 1 tbl |
