UNIVERSAL MECHANICAL CENTRALIZING DEVICE Russian patent published in 2005 - IPC

FIELD: oil and gas well drilling, particularly support-and-centralizing devices for bottomhole assembly to perform directionless path control and well wall calibration.

SUBSTANCE: centralizing device comprises body, spring-loaded centering members arranged in grooves and spaced equal distances one from another. The centering members form calibrating diameter of the device. Centering members are arranged in even or odd manner, concentrically or eccentrically one to another and installed in mating grooves directed at 4°-9° to body axis. The mating grooves converge towards device bottom. Stop nut for calibrating diameter regulation is located on outer body surface in top part thereof. Stop nut is joined with the body by left-handed connection thread and has longitudinal orifices extending along stop nut axis. U-shaped shear clips destined to prevent bottomhole assembly sticking are inserted in stop nut orifices.

EFFECT: increased efficiency of bottomhole assembly operation, possibility of rapid changing the main bottomhole assembly parameters, extended range of application due to solution of some technical problems, possibility of device usage for underbalanced drilling.

2 cl, 3 dwg