Engineering Techniques to Drill Successive Wells under Different Conditions and Their Example Analyses in Sichuan-Chongqing Region

Three ways to drill successive wells are described,including casing sidetracking in an original well, drilling a new hole within the same well site and drilling a hole in an adjacent other well site.The success examples of drilling successive wells,such as Luojia 16H-1,Xinqingxi 1 and Xin 856,are analyzed.The results have indicated that major gas discovery wells need to be closed by a long cement plug if they are heavily out of control and have shortcomings of hole structure and engineering.For drilling a successive well , the comprehensive geological prediction of fractures is a prerequisite ,and directional drilling is a key step. Drilling a horizontal successive well can penetrate much more high dip fractures and increase gas production capacity.