METHOD OF OIL-GAS WELL CONSTRUCTION Russian patent published in 2001 - IPC

FIELD: construction of oil and gas wells, particularly, well washing and protection of fresh water from pollution with drilling mud. SUBSTANCE: method includes mounting of drill, drilling and installation of equipment for wells of service water supply. For construction of oil-gas well, drilling equipment is mounted. Drilling mud is prepared on base of mineralized water. Water is taken from wells of service water supply. Cutting of bottom hole rock of oil-gas well by bit is carried out simultaneously with forcing of drilling mud at pressure to bottom hole. Drilled-out rock is lifted to surface. Fresh water is used for preparing drilling mud for surface well drilling of wells of service water supply and oil-gas well. Water is taken from local open water reservoirs formed with ecologically clean fresh waters coming to day surface. Waters are similar in their qualitative composition to drilled fresh waters. Mineralized water is used for preparation of drilling mud which is used after lowering and fastening of surface casing string of oil-gas well. EFFECT: higher ecological safety of well construction. 2 dwg, 1 tbl