Key words: drilling mud, clayey shale, borehole profile, assembly of drilling string bottom
Drilling companies often have problems during horizontal wells constructions such as abnormal geological conditions bringing WOB, high coefficient of friction in directional of wells, cleaning of well from cutting and etc. On the example of Michayuskoe field we provide complex solutions of these problems. They are directed to safekeeping the stability of lithified clays rocks by increasing inhibitory and bridging abilities of clay-free drilling mud. This type of mud is composed of potassium inhibitor with high molecular weight, polysaccharides, organic inhibitor and carbon black. Frictions forces (or resistance to movement of the boring tool) are evaluated to optimize the composition of the drilling layout boring tool while drilling in directional wells. This solution takes into account placement of steel drill pipe and heavyweight drill pipe with considering power options, borehole profile, and parameters of drilling mud. While noting considerable attention should be paid to the lubrication of drilling mud since its effect will be significant for coefficient of friction in horizontal parts of wells.
