PROCESS OF OPENING OF PRODUCTIVE POOL OF WELL

oil and gas production, technology of secondary development of productive pool shut off by casing strings, high-speed jets of drilling fluid. SUBSTANCE: in correspondence with process perforation passages are created in casing string, cement stone and in seam. High-speed jets of drilling fluid with speed nor less than 130 m/s are used for this purpose. Passages are created in two stages. At the beginning passages in required point of seam are created. Then they are formed at distance not closer than (8-12) dn, where dn is nominal diameter of jet across butt of nozzle. Time of formation of first passages exceeds time of creation of holes in casing string on ground surface by factor of four as minimum. Time of formation of second passages is at least twice as much as time of creation of first passages. Content of solid phase in drilling fluid is not less than 8% of volume of drilling fluid. EFFECT: raised efficiency of perforation of casing string with drilling fluid. 1 dwg