DEVICE FOR WELL CEMENTATION Russian patent published in 2004 - IPC

FIELD: oil and gas wells construction and operation. SUBSTANCE: device has hollow body as part of casing string, operation plug, branch pipe, shear mounting saddle for operation plug. Said saddle is mounted in the branch pipe, in lower part of casing string. On outer surface of body above the shear saddle assembled soft cover is placed. Spring deflectors are also provided, one ends of which are rigidly connected to outer surface of body, while other ends are connected to respective ends of soft cover, which are fixed in transporting position by differential bushings. These bushings are connected to the body by hollow pins. They are made capable of their destruction during interaction with plug and of operation pressure transfer from body hollow through pins hollows into differential bushings hollows. This assures movement of differential bushings and freeing of spring deflectors ends together with soft cover. Expanding of latter occurs in radial direction in operating position of device with pressing ends of soft cover to well wall. EFFECT: increased device operation reliability. 5 cl, 3 dwg