Experimental study of shale drillability with different bedding inclinations under varying wellbore pressure conditions

Abstract In the practice of shale gas development engineering, it is important to understand physical and mechanical properties shale. The bedding inclinations are known significantly influence its properties. This study mainly examined on drillability under different wellbore pressures. used in this varied from 0° 90°, with a gradient 15°. pressure values 0 25 MPa, 5 MPa. results show that index increases exponentially increasing at inclinations. proposed exponential empirical model can describe relationship between pressure. When less than 15 index, shows “W”-type variation trend as increase range 90°. decreases gradually impact virtually undetectable. provide reasonably insight into effect deformation drill bit, useful prediction for situ conditions.