CENTRALIZER-STABILIZER OF THE DRILL STRING WITH EXTENDABLE ROLLERS Russian patent published in 2023 - IPC E21B10/34 E21B17/10 

FIELD: mining industry.

SUBSTANCE: invention relates to the field of construction of oil and gas wells, namely to devices that provide centering and stabilization of the layout of the drill string in the wellbore. The downhole roller centralizer comprises a cylindrical housing with at least three longitudinal grooves equidistant from each other along its surface. In each groove on the axis parallel to the axis of the device, there is an extendable roller having a hinged connection with movable elements. The housings of the sliding rollers are made with the possibility of rotation relative to the axis. A through groove is made on each end side of the longitudinal groove. There are two hollow rods in the housing, when the rollers are extended, moving progressively towards each other. Each of the rods is spring-loaded with a return spring. On each hollow rod, cam pushers are fixed according to the number of rollers with eyelets and a piston with the possibility of translational movement of the hollow rod with a piston relative to the device housing in its through bore. One hollow rod hydraulically isolates through grooves made on one end side of the longitudinal grooves, and the other hollow rod hydraulically isolates through grooves made on the other end side of the longitudinal grooves. In each of the through grooves there is a double–arm lever mounted on the axis of rotation by means of a finger fixed in a transverse hole made in the device housing, and pivotally connected on one side to the eyelet of the cam pusher, and on the other side to the axis of the extendable roller by means of pins. The through grooves on the outside are closed with protective covers, and the extendable roller housings are rotatable relative to the axis by means of rolling bearings.

EFFECT: increase in the reliability of the device in the process of extending and returning the rollers to their original position by eliminating the impact of the external environment on the elements of the device involved in this process and reducing the number of moving links.

2 cl, 9 dwg