METHOD OF DETERMIiNING FRICTIONAL COEFFICIENT OF BOREHOLE OF HORIZONTAL WELLS

On the basis of established model of frictonal force, frictional coefficient of different section of horizontal wellbore is determined through measured data while drilling. The method of increasing frictional coefficient is properly used to predict the frictional force of designed path of later horizontal wells. Thus, reliable data is provided to the optimized designing of horizontal well drilling. The method of increasing frictional coefficient is finished by repeatedly comparing computing the frictioal force of corresponding section of designed and drilled path of the same well. Modified factor of frictional coefficient of different sections of designed path of one field or area is obtained by statistical computing and analysis of more wells.