Leakage check method of casingprogram design for horizontal wells

Horizontal wells have become an important technology for effectively developing oil and gas at present. With wellbore goes forward, well leakage is likely to occur on horizontal section because of the particularity of formation fracture pressure for horizontal wells, which affects the drilling efficiency and drilling cost. Considering the characteristics of formation fracture pressure and force analysis of horizontal section during drilling, a new leakage check method was developed with consideration of the annular dynamic pressure and practical experience of drilling. This method was safer, more efficient and more cost-saving than conventional design methods.