DEVICE FOR CONTROL OF BEHIND-CASING FLOWS BETWEEN TWO FORMATIONS Russian patent published in 2016 - IPC E21B47/11 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to oil and gas industry, in particular to means of control casing flows in borehole fluid. Device contains lowered on geophysical cable container for tracer fluid with feed assemblies and unsealing, as well as measurement sensor. Ferrofluid is used as tracer fluid and devices for magnetic field measurement are used as measurement sensors. Container is placed to pipe string equipped from outside with a packer set between upper and lower formations. Feed Assembly is made in form of a perforated plug rigidly mounted on lower end of pipe string. Depressurisation unit is made in form of a row of radial holes made on lower end of container and hollow bushing equipped with top inner circular ledge arranged in cylindrical recess made on external surface of container. Hollow bushing is spring-loaded from bottom of container and is equipped with a row of openings. In transport position row of radial holes of container is tightly covered by spring-loaded hollow bushing, and in working position at unloading container on a perforated plug hollow sleeve has possibility of restricted axial movement upwards relative to container and alignment between a row of radial holes of container and row of openings of hollow bushing. Measurement sensor is installed on pipe string above packer opposite upper formation.

EFFECT: technical result consists in improvement of reliability and efficiency, high accuracy of presence of behind-casing flow between two formations, excluding sealing logging cable at wellhead.

1 cl, 3 dwg