Research On The Slimhole Horizontal Well Drilling Speed Improvement In Changling Gas Field Of Jilin

Sofar, horizontal wells have become the base technology of oil&gas development athome and aboard. The number of horizontal wells drilling increases rapidly, the scope ofapplication expands gradually, and the technology becomes more and more perfect. Inrecent years, horizontal wells has became more and more important in domestic oil fielddevelopment, the drilling technology in improving driiling speed has also got greatimprovement. But with the low qulity of resources, some new problem appeared, mainlyfocused on drilling speed and drilling cost of horizontal wells, especially for the low pressure,low permeability and low yielding lardge structural-lithological reservoirs and strongheterogeneity formation, using regular drilling technology, low efficient,low speed and highcost is inevitably. Beside, some oilfield has complex geological conditions will also increasethe diffculty of horizontal wells drilling.Changling Denglouku gas reservoirs has rich gas and the effcient development of thisresource is very important for Jilin Oilfield to continuesly improve its natural gas output. ButDenglouku is a low cavity, low permeability, tight gas resvior, buried more than3500metres with poor drillablity and strong abrasive, it was proved that regular technology is hardto be used here for efficient development because of low drilling speed and high drilling cost,so since2011, slimhole horizontal well is adopted, but there are still some diffculties neededto be solved.The first is how to improve the drilling speed of build up section and horizontal section.The second is how to improve the efficiency of trajectory controlling. The third is how toreduce the drag and torque, clean up the bore hole.This project focuses on the drilling speed improvement problem, based on the theoryanalysis and field experiment, successfully selected the suitable PDC bit and researched thehorizontal well steering BHA design method, formed a set of Changling Denglouku slimholehorizontal well drilling technology, and great effect is achived during field application.