TOOL FOR GRAVEL PACKING OF INTERVAL INSIDE WELLBORE AND METHOD OF GRAVEL PACKING OF INTERVAL INSIDE WELLBORE Russian patent published in 2001 - IPC

FIELD: mining construction, particularly, devices and methods of gravel packing with use of low-viscosity liquids. SUBSTANCE: tool includes pipeline containing lower main section and upper section of filter. Downhole tool is lowered into interval to be packed and pulp is forced into annular space round filter. In this case, liquid flows out of pulp through perforations in casing, and gravel, during same time, drops onto bottom of annular space with formation of gravel packing. When gravel packing rises above uppermost perforations, liquid from pulp starts rounding gravel packing, passes through bypass filter, through washing pipe to pipeline and outside from lower end of main filter to pack perforations in casing to improve distribution of gravel in gravel packing inside annular space. EFFECT: increased quality of materials mined from bed. 10 cl, 3 dwg