Study On Process Engineering Of Wellbore And Fluid Stability Of Complicated Well Condition In Ningding Block

Through investigates and statistics on current situation of drilling fluids technology on each horizon in Ningding block and analysis on traditional sealing technology and anti-collapse measures,the paper figur out common plugging techniques exist for a single cause of the leakage and plugging effect not ideal,the recurrence rate and more problems,especially for large complex leakage wells,the use of conventional bridge plug,chemical gel static plugging,chemical gel gap plugging,chemical gel plugging mud and lime trailing cementing technology is not obvious effect,often repeated over and over again,it will miss the best anti collapse time,and the formula is complex,not with the deep structure and geological structure of the change,so that the formation of the system has a resistance and defects.Thesis simulat sand bed by 3 mm and 10 mm steel ball plugging effect evaluation and 5 mm fracture plugging effect evaluation,contrast API fluid loss plugging indoor experiment,as well as the main agent of PAC,ZDS,Na OH,SF,clay,sodium formate collapse prevention formula optimization indoor experiment,,the paper select the anti-leakage formula containing HHH complex structur materials and other anti-leakage materials and anti-collapse formula containing 3% Bentonite,0.3%PAC,4%ZDS,1%SF,7%Na COOH and 0.1%Na OH,and test and verifi the optimiz drilling fluid technology methods on oil filed as well as gave simple introduction of methods in handling with common sticking of tool accidents.