DEVICE FOR HYDRAULIC FRACTURING OF ROCKS IN WELL Russian patent published in 2018 - IPC E21C39/00 

FIELD: mining.

SUBSTANCE: invention relates to mining – to instruments of mining geophysics, and is used to determine stresses in a rock mass by injecting liquid under pressure into a sealed section of a well before destroying its walls. Device comprises a cylindrical body (hereinafter – the body) with sealing elements installed at its ends and a mechanism for compressing the sealing elements between them, with two channels in the body. Sealing elements have conical recesses at both ends, and the mechanism for compressing the sealing elements consists of a stationary rod integral with the body, with two cylinders symmetrically mounted on the body and axially movable, each cylinder has a conical protrusion at one end. Conical protrusions of the cylinders contact the conical recesses of the sealing elements adjacent to them, and conical portions of conical grooves, mounted on the body at its ends, contact the conical recesses. Working cavities of the cylinders are connected to one of the channels provided in the body, and the other channel of the body is connected to an opening on the cylinder-free side of the stationary rod. In the working cavities of the cylinders there are installed valves overlapping the channels by which the working cavities of the cylinders are connected to the cavities under the sealing elements. On movable valve rods, there are shanks for restricting the cylinder stroke.

EFFECT: elimination of loss of stability of sealing elements during compression by providing their additional pressing against walls of the well.

1 cl, 1 dwg