ANCHOR-CENTRALISER OF STEPANOV HYDRO-MECHANICAL STRUCTURE Russian patent published in 2009 - IPC E21B17/10 E21B23/00 

FIELD: oil-and-gas production.

SUBSTANCE: invention related to casing string hole clearance cementing , particularly cementing casing string in a well. Hydro-mechanical anchor centraliser, includes cylinder connected to string, inside which installed 3 barrels, executed as half barrels, connected in pair with each other via seals, working piston, installed under barrels and executed as half barrels, stiff fixed in a conical part, centralising arms, roller fixed with string, lockers, executed as a T-shaped channels on the barrels bottom, interacting with T-shaped pins, stiff fixed with centralising arms top ends, destroyable plug, installed in radial hole with thread, connecting internal cavities of cylinder with string, stepped executed along its external working surface, slide barrel with conical external surface on its top part for interaction with cylinder internal conical surface and radial hole, located under conical surface, installed over barrels and on bigger diametre of the string inside cylinder internal cavity with possibility of radial hole closing with it after anchor centraliser actuation and executed along external diametre, less tha cylinder internal diametre, and actuation, fixed relatively to cylinder working barrel, and on the bottom part of working barrel along generating line radial pins executed in gaps between centralising arms.

EFFECT: anchor centraliser reliability increase.

4 dwg