METHOD FOR SECONDARY OPENING OF PRODUCTION STRATUM Russian patent published in 2009 - IPC E21B43/11 E21B33/14 

FIELD: oil-and-gas production.

SUBSTANCE: invention related to oil-and-gas production, particularly to oil fields development, and used for executing of production stratum secondary opening. Essence of the invention is in cementing of the well and descending piping strings with installed on a case with a plug fitting made of acid-soluble material, washing out of the well and pumping an acid into the production stratum, well development. According to invention case is installed on tubing strings using automatic locker. Case has a centraliser and supports. Between the free end of the well and its bottomhole create a gap big enough to dislocate plugs. Before the cementation the horizontal well bore wash it out with high content foam with 5-10% magnesium content, with a volume equal to two volumes of horizontal well. After that cement horizontal well with a slurry, which have a certain filtrating qualities, based on polyurethane hydrophilic polymer, pumped with volume equal to cemented gap volume. Therefore lift up tubing pipes and disconnect them from case, supply them with slurry and hydrochloric acid, separate them from a well fluid and each other with acid resistant plugs with the immediate well fluid displacement along the gap between tubing pipes and well wall. To be supplied untill slurry reaches the bottom hole. After that connect tubing pipes with a case and continue supply till the pressure drop, triggered by interaction of the second plug with case supports. After some times well to be developed.

EFFECT: diversified range of application due to slightly cemented collectors use, and increase in efficiency due to non-perforated opening of the collector, and decrease of a well product watering.

1 tbl, 1 dwg