Study On Strongly Inhibitive Drilling Fluid System In Su 53 Area

The pressure bearing capacity of upper strata is low in Sulige block,and the "double shi layer" is easy to collapse,Improve drilling fluid density,easily lead to leakage.In highly deviated wells in well bore stability,collapse is serious,easy resistance and sticking,"double layer" collapse formation is in highly deviated wells,which not only increases the collapsed length,while balancing the mechanical stability of the well bore is changed.This is the fatal factor that leads to the collapse of the horizontal well and the horizontal well.The contact area of drilling fluid and gas reservoir is increased,the drilling time is relatively long,and the possibility of gas pollution is increased.These problems have seriously restricted the normal drilling process,and it is very important to study the strong inhibitive drilling fluid system.In this paper,through the study of reservoir of Su 53 block,analyses the existing problems of drilling fluid system of strong inhibition,to carry out the indoor formulation and evaluation test,optimization of the amphoteric sulfonic acid copolymer to replace the original formulation of various silicone filtration reducing agent and tackifier,and introducing bionic wall by adjusting agent GBFS-1.Silicone dosage form bionic well bore strengthening type drilling fluid system formula.The original fluid silicone drilling fluid loss agent system(SMP-2,SPNH,KH-931)is replaced by amphoteric polymer sulfonate,and the polymer has strong coating ability,reduce shale hydration expansion;adding bionic solid wall agent GBFS-1 enhanced near well bore rock strength,maintain well wall stability.The new drilling fluid system has good anti collapse ability.Considering the mechanical and chemical factors,application of bionic idea improved near borehole wall collapse prevention rock strength,borehole wall stability effect is outstanding,has a good ability of preventing collapse.The field test was carried out.Through the summary and analysis,the bionic drilling fluid system and its construction technology were improved.