DEVICE FOR SAND BRIDGE REMOVAL FROM WELL Russian patent published in 2003 - IPC

FIELD: well operation and servicing. SUBSTANCE: device has breaking mechanism consisting of hollow cylindrical body accommodating coaxially installed movable shaft whose upper part is made in form of turbine. Breaking mechanism upper part is rigidly connected with hollow rod spring-loaded with return spring and ensuring its mobility in axial direction. Breaking mechanism lower part has crown rigidly connected to cylindrical body. Crown is made in form of sleeve. Sleeve upper part is hollow. Sleeve lower part has vertical water holes symmetrical to axis and mutually perpendicular plates rigidly secured to sleeve lower side surface. End lower surface of said plates is reinforced with hard-alloy cutters and is trapezoidal in shape. Mounted on movable shaft are upper disk and lower disk with circulating channels. Disks are mounted on journals of movable shaft. Rigidly fitted on movable shaft is cam. Sleeve lower part has end teeth and radial channels communicating device internal cavity with annulus. Circulating channels of disks are located symmetrically relative to device axis. EFFECT: higher efficiency of breakage of sand bridge. 2 dwg