PROCEDURE FOR HYDRAULIC BREAKDOWN OF FORMATION IN HORIZONTAL BORE OF WELL Russian patent published in 2010 - IPC E21B43/26 

FIELD: oil and gas production.

SUBSTANCE: horizontal bore of well is drilled in oil-non-saturated section of producer; whereupon annular space between casing and rock of horizontal bore of well is cemented. A hydro-mechanical slit perforator performs perforation azimuthally directed with intervals per one round-trip operation. Further, there are lowered packers cutting each interval equal to length of a formed slit from the rest part of the string. Hydraulic breakdown of the formation in a horizontal section of the well is carried out successively starting from the perforated section of the horizontal bore of the well distant from axis of a vertical bore of the well. Also hydro-mechanical slit perforation is double-sided; the slits are arranged at 180° relative to each other in vertical plane opposite to each other relative to axis of the horizontal bore of the well in one interval. Hydro-mechanical slit perforation can be also made one-sided with a turn of 180°in vertical plane relative to axis of the horizontal bore of the plane in turn every other following interval, or in staggered way equal to length of a formed slit. One-sided hydro-mechanical slit perforation is made in the direction of a formation roof at low thickness of the producer and at active bottom water.

EFFECT: raised efficiency of directional HBF and minimised amount of round-trip operations at secondary formation opening-out before HBF.

2 cl, 3 dwg