METHOD TO ISOLATE WATER-BEARING RESERVOIR INSIDE WELL Russian patent published in 2008 - IPC E21B33/13 

FIELD: oil and gas production, particularly methods or devices for cementing, for plugging holes, crevices, or the like.

SUBSTANCE: device comprises technological pipe string lowered in well and reagent supply unit installed at well head. Technological pipe string is provided with radial channels opposite to penetrated water-bearing reservoir. The radial channels are sealed with hollow bush from inside. The bush is retained with shear member and may perform limited axial sliding in downward direction relatively technological pipe string. Reagent supply unit is made as upper and lower top cementing plugs installed in technological pipe string and retained with lock members so that it may be released and slide downwards in axial direction. Technological pipe string is provided with upper, lower and central supply pipes arranged over, under and between top cementing plugs correspondingly. Lower top cementing plug may cooperate with hollow bush.

EFFECT: increased water-isolation quality and extended water-isolation result duration.

2 dwg