APPLICATION OF MMH DRILLING FLUID IN MENXI-3 WELL IN CHUANDONG AREA

Sand bridge and sediment are found in the 311mm hole in Chuandong Area,reaming operations are required,while well slough is likely to happen in shale formation,especially when high dip angle exists.Laboratory test and field practice of MMH drilling fluid were conducted.The results showed the unique rheology of "solids-liquids" conversion,with the structure formed and broken quickly.Other advantages inclued low viscosity in nozzle,high Casson dynamic shear force and shear thinning cofficient,good wellbore cleaning capability and inhibating effect,as well as high well stability.