DOWNHOLE CALIBRATOR Russian patent published in 2023 - IPC E21B10/26 

FIELD: mining.

SUBSTANCE: invention relates to a rock cutting tool, namely to a downhole calibrator. The calibrator includes a hollow body with a central flush channel. On the outer surface of the body, reinforced with wear-resistant inserts, alternating long and shortened blades are made. The lower surfaces of all blades are set at the same level, and the upper surfaces of the long blades are above the upper surfaces of the short blades. Each shortened blade contains internal horizontal and vertical channels. The horizontal inner channel runs from the central flushing channel of the calibrator body along its radius. The horizontal inner channel merges into an upwardly directed vertical inner channel emerging on the upper surface of the shortened blade. An ejection nozzle is installed at the exit from the vertical internal channel, forming after itself an ejection chamber between the borehole wall, the calibrator body and the side walls of two adjacent long blades. The ejection nozzle of the vertical internal channel of each shortened blade is made with an internal surface tapering along the movement of the flushing liquid, having a polyhedral shape in cross section. The inner tapering surface of the ejection nozzle in each of its many cross sections along the entire length of the ejection nozzle has the shape of a polyhedron. Each ejection nozzle is fixed relative to the blade against rotation, and the specified shape of the polyhedron of the cross section of the inner tapering surface of each ejection nozzle is positioned so that one of the vertices of the set of angles of the polyhedron is oriented towards the axis of the calibrator, the second of the vertices of the set of angles of the polyhedron is directed towards the incoming face of one adjacent long blade, and the third of the vertices of the set of angles of the polyhedron is directed towards the escaping face of the other adjacent long blade.

EFFECT: qualitative distribution of the flow over the elements of the calibrator.

4 cl, 6 dwg