DEVICE FOR PLACING CEMENT PLUG IN WELL Russian patent published in 2011 - IPC E21B33/14 

FIELD: mining.

SUBSTANCE: device for placing cement plug in the well includes hollow cylindrical housing; lower cement plug with through channel, which is equipped from above with plug catching baffle for upper cement plug and connected by means of shear elements to the housing; casing attached to the housing, and side flushing ports. Through channel of lower cement plug is provided along its axis, and side flushing ports are arranged on the casing which is made in the form of a branch pipe with the length of more than lost-circulation zone and equipped from above with a cavity and from below - with shoe with valve and fastener for lower cement plug; at that, plugs, casing and shoe is made from easily drilled material. Side channels have the possibility of tight overlapping of lower cement plug at its downward movement till lower cement plug interacts with the shoe fastener.

EFFECT: proposed device for placing the cement plug in the well is reliable design for isolation of troublesome zone at well drilling by the controlled delivery of cement slurry to the specified well hole and its separation from the well fluid in order to create cement plug of high quality with the channel for subsequent drilling.

3 dwg