FILTERING WELL CONSTRUCTION TOOL Russian patent published in 2006 - IPC E21B33/14 E21B43/04 

FIELD: mining, particularly production or injection wells, as well as for well completion.

SUBSTANCE: tool includes production and filtering strings, circulation valve provided with shear plug, flushing channels and shutoff bush for flushing channels closing. The shutoff bush has shear plug and is made as cementing plug. Circulation valve plug and shutoff bush plug may be sheared as the shutoff bush is installed on circulation valve seat to close all flushing channels and to prepare the well for following operation. Production string has smooth inner surface.

EFFECT: increased efficiency due to possibility to overlap working operations and due to well diameter reduction.

2 cl, 1 dwg