DEVICE FOR WATERPROOFING OPERATIONS PERFORMING IN WELL Russian patent published in 2008 - IPC E21B33/13 

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

SUBSTANCE: device comprises flow column and pipe string arranged inside it. Flow column has stem arranged at lower end thereof. Pipe string has radial channels formed in lower pipe string part and is sealed below the channels. Radial channels are air-tightly sealed with bush having side channels. Bush may perform limited upward movement to align side channels with radial pipe string channels. Disc valve with seat is installed between flow column and stem. Seat has rupturable member, which retains seat in opened state. Lower part of pipe string may hermetically seal disc valve seat and cooperate with rupturable member. Stem has hollow end part provided with plug installed inside end part so that the plug may perform limited upward movement as plug rests upon well bottom. The end part has radial channel, which may be hermetically closed as plug slides upwards.

EFFECT: increased waterproofing efficiency.

2 dwg