Horizontal Drilling Techniques in Longdong Gas Field

To tackle the challenges of wellbore instability, low rate of penetration and lengthy drilling time encountered in horizontal drilling in Longdong Gas Field, the investigation of horizontal drilling techniques was carried out. The casing program was designed as a three-spud structure according to the formation features, with the surface casing isolating the fragile formations; the well trajectory was designed as five sections to meet the target distance requirements and ensure smooth well trajectory; applicable well trajectory control techniques were used according to the well trajectory requirements at different sections; PDC bits and drilling fluid were optimized in line with the formation characteristics of the various well sections, and corresponding maintenance measures were taken, by which a set of horizontal drilling techniques applicable to Chengdong Gas Field were developed. Field application showed that the horizontal drilling techniques in Longdong Gas Field can solve the problems occurred in the drilling process, increase the rate of penetration and decrease the drilling time.