There are large sections of mud shale in the upper well section of Block E in Thailand,which makes it easy to make pulp and collapse.The target reservoir is an igneous fracture type oil and gas reservoir.The window of construction safety density is narrow,and the leakage can easy to occur in the same layer.Because of this situation,the K2SO4 amine-based drilling fluid formula was researched in the lab,the results showed that the combination of K2SO4 and organic amine TJX-1 obviously improved the inhibition,the expansion rate of shale was decreased by 72.1%,and the rolling recovery rate reached 92.9%.The rheological properties of the optimized drilling fluid system were stable,and the addition of film-forming blocking agent LXJ-1 can significantly improve the plugging performance of the drilling fluid.Based on the difficulties with the construction in the field,a supporting technical scheme was formulated and successfully applied to several wells,such as WBEXT-3D.The problems of slurry formation and shaft wall collapse of soft mud shale are effectively solved,the complexity of target formation leakage is effectively controlled,and the rate of penetration(ROP)of the well in the same block is increased by 43.5%.
K2SO4 amine drilling fluidinhibitionblock to prevent collapsespray leakage in the same layer
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NSTL
维普
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