Research On The Gasification Well Drilling Technique

At present research demonstrate gasified fluid drilling is an economical method in under balanced drilling. It can reduce formation damage causing by drilling fluid dropout and eliminate"chip hold down effect"greatly and enhance ROP enormously. Through the research of power computation of gasified fluid drilling, the gasification drilling fluid system, the gasification drilling implementation plan and the gasification drilling well completion plan and so on,the model and design software was build up. With the aid in the model and the software,we can obtain the master data such as the pressure drop computation heterogeneity pipe flow fundamental equation,the ability of that gasification drilling fluid take along the filings,the density of gasification drilling fluid and the gasification drilling fluid return velocity and so on. Thus we further obtains that the equipments need to choose which in the well drilling process and the synergy. The higher gas fluid ratio is,the more liquid head reduces are,and in the same well depth equivalent density is lower,the gasification well drilling enhancement drills fast is more obvious; The gasification may realize the water base drilling fluid to realize in the pore pressure coefficient 0.7~1.15 stratum under balanced drilling; The gasification well drilling implementation plan is practical and feasible,the gasification well drilling and the conventional well drilling transformation is convenient,can meet the field conduct request; Carrying on the survey using the bottom hole pressure test attachment to the bottom of the well fluid column actual pressure,and carrying on the contrast with the software computation,the software computed result and the measured data difference is smaller than 3%,can meet the field conduct request. The application software carries on the computation analysis and the field test result tallies very well,indicates that this software to gasifies the well drilling to have the instruction function; The complexed aluminum complex ion gasification drilling fluid system,the bore hole is stable,takes along the filings performance to be good, the degasification is normal, can meet the gasification well drilling construction needs; The gasification drilling fluid takes along the filings ability to take along filings ability compared to the conventional drilling fluid,may reduce the liquid displacement suitably for the enhancement drilling rate; Because the ability taking along the filings of gasified fluid drilling is better,and it reduces regrinding,moreover enhancing advance rate,it can also enhance the single drill bit footage.My dissertation's emphases are modifying the establishment model that basing on Daqing Oil Field's scene actual data and obtaining a set of new models which conform to the well drilling actual circs,and compiling the software under the new model's foundation to convenient field construction request. These researches are great development to gasified fluid drilling and have very important theoretical significance.