Kuntsiak Y. Development and introduction the complex of tools and technologies for drilling of inclined directional and horizontal wells (applied for oil and gas fields of Ukraine)

Dissertation is designed on development and introduction of the set of highly efficient tools and technologies for drilling of inclined directional and horizontal wells in complex geological conditions of rocks’ bedding subject to sloughing, collapsing and narrowing of the well bore. As a result of theoretic, experimental and field researches the effect patterns were established between well inclination and dog-leg severity of well bore, type of drilling fluid and drilling time for intervals consisted of unconsolidated rocks onto stability of well walls within the oil and gas fields of Dnepr-Donetsk Depression and shelf of Black sea as well as the range of its critical values for specified rocks was calculated. The new BHA with excentrical anti-stuck cross-overs were designed that prevent drill pipes sticking to the lower wall of the well bore and provide the better weight on bit