CORE EXTRACTOR Russian patent published in 2014 - IPC E21B25/00 

FIELD: oil and gas industry.

SUBSTANCE: core extractor includes a tubular housing, an upper adapter connected to the upper part of the tubular housing, which is intended for connection to a spindle of a hydraulic downhole motor or to a drilling string, and a lower adapter connected to the lower part of the tubular housing. A core receiver made in the form of one or more pipes connected to each other is located inside the tubular housing. The upper part of the core receiver includes a rotation support and an adjustable suspension. Its lower part includes a device for separation of core from the mine face, which is made in the form of collet and lever core grippers arranged in a sleeve. The sleeve is connected to the lower part of the core receiver pipe. Besides, it includes the lower sealing assembly made in the form of a diaphragm covering the core receiver cavity from the mine face. The diaphragm covering the core receiver cavity from the mine face is fixed between the lower part of the core receiver pipe and the upper part of the lever core gripper. In the core receiver rotation support there installed is a threaded plug covering the core receiver cavity from the tubular housing cavity. The core receiver cavity between the diaphragm and the threaded plug in the rotation support is filled with insulating liquid. The adjustable suspension is made in the form of a threaded tubular element tightly insulated from upper part of the tubular housing. In the threaded tubular element there are through channels intended for pumping of a drilling agent through the cavity between the tubular housing and the core receiver, which is restricted in the lower part with a drilling crown. The rotation support in the upper part of the core receiver is tightly insulated from the core receiver cavity filled with insulating liquid. Besides, it is equipped with an axial damping device, provided with through channels intended for pumping through it of some part of the drilling solution to the cavity between the tubular housing and the core receiver, which is restricted in the lower part with the drilling crown.

EFFECT: improving reliable preservation of formation parameters of core using insulating liquid to prevent core contact with the drilling agent; reducing dynamic loads on a suspension rotation support during drilling and separation of a core string.

4 cl, 4 dwg