DEVICE TO PERFORM WATERPROOFING WORKS IN WELL Russian patent published in 2007 - IPC E21B33/13 

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

SUBSTANCE: device comprises pipe string lowered in well and provided with shoe at end thereof. The shoe is made as hollow bush and provided with liner formed in end part thereof and with self-sealing collar located from outside thereof. The liner has through orifices. The collar provides flow in bottom-top direction. Pipe string has partition located in lower pipe string part. Upper and lower radial channels are correspondingly formed over and below partition. The liner may cooperate with well bottom. Hollow bush may perform limited movement in upward direction with respect to pipe string and seal lower radial channels.

EFFECT: elimination of cement surge tank usage for waterproofing composition preparation and increased waterproofing works quality.

1 dwg