Research On Optimum And Crucial Drilling Technology For Deep Well In Northeast Sichuan

With the development of domestic oil and gas exploration and development,the deep well has been increasing.During construction a deep or ultra deep well in northeast of Sichuan,there are general difficulties such as complex geological conditions and wellbore structure,strong abrasive formations.The above problems lead to low ROP,long drilling and completion period,and high drilling cost.In order to solve the problems of increase drilling speed,it's importance to research optimal and fast drilling technologies,increase the bit footage and time,increase drilling speed.This paper carry out a study of optimal and fast drilling Program for deep and ultra deep wells in Northeast Sichuan.This paper investigates a large number of documents,and applies the latest research results of Ultra deep well drilling engineering in the world.the basic characters of regional structures and formations,well structures and the present technologies of drilling and completion in deep and ultra deep wells are analyzed and studied.Based on theoretical research and combined with drilling data analysis,this thesis studies the matching technologies of optimal and fast drilling Program in Northeast Sichuan.It carried on the theoretical research and application effect analysis from the following aspects,such as formation characteristics analysis,well structure optimization and design and feasibility analysis of gas drilling,rock breaking tools and power drilling tools,etc.The optimized structures of exploration wells are 20"-13 3/8"-10 3/4"-7 5/8"-5 3/4".The optimized structures of development wells are 20"-13 3/8"-10 3/4"-7".Gas drilling technology can be used in the upper large wellbore but if there are water production intervals,foam drilling should be choosed.Gas drilling technology,turbodrill combined with impregnated bit and PDM cooperate with multiple drill bit can be used when drilling into the formations from Ziliujing to Xujiahe.If the hole is stable,air hammer will be a good choice.Uniform thickness PDM and PDC bits are suitable for marine stratum.In this paper,the matching technologies of deep well and super deep well enriched the theoretical system and research content of drilling and development in Northeast Sichuan.It not only solve the problems of low ROP and long drilling period,but also contribute to safe drilling,energy saving,environmental protection,and reducing the cost.This paper has a very important guiding significance and practical value for the development of deep oil and gas.