RU2253006C1 - Drilling body for extracting directed core - Google Patents

Abstract

FIELD: geophysics.

SUBSTANCE: device has column pipe with branch pipe, drilling crown with core extractor and directing device. Core-directing device is made of flexibly deformed pipe in form of closed ring, free ends of which are connected by sliding collar. Ring-shaped pipe is mounted in ring-shaped recess, made along inner surface of upper portion of core-extractor and is filled with non-aggressive liquid with low viscosity. Inside the pipe two balls are freely positioned. Balls are made of hard material. On of balls has density greater than density of liquid in the pipe, and other one has, on the contrary, lesser density. During directing process first ball sinks, and second one floats. This feature allows better precision during when positioning core in special plane.

EFFECT: simplified construction, higher reliability, higher trustworthiness.

3 dwg

Description

The present invention relates to devices for producing and retrieving undisturbed oriented core and may find application in the sinking of wells by the core method in solid rocks.

A device is known for the extraction of oriented core (AS No. 75970 IPC E 21 V 47/02 BI No. 32 - 1980). The device comprises a core projectile, a crown, a longitudinally movable core breaker and an orientator. In this case, the orientator is made in the form of rings interacting with each other from plastic material, a spring and a movable sleeve and is located under the core cutter with the possibility of interaction with it.

The disadvantage of the device according to A.S. No. 759709 - a high probability of error in determining the position of the apsidal well plane.

A device is also known for the selection of oriented core (AS No. 883121, IPC E 21 B 25/16, BI No. 43 - 1981). The device comprises an outer pipe with an adapter and a crown, an internal core collection pipe, a mechanism for marking the core connected to the core collection pipe, and an apsidal plane position sensor with a multiple marking mechanism and a clamping element in the gap between the soft metal plate and the movable heel on a spring loaded stock. In this case, the marking element is made in the form of a group of balls of different diameters, the rod has an injection channel for moving the balls in the clamp gap, and the heel of the clamp and the soft metal plate are located inside the core-receiving pipe, which is spring-loaded with the possibility of longitudinal movement relative to the outer pipe.

The disadvantage of the device according to A.S. No. 883321 is the complexity of its design.

A well-known core orientator for the selection of oriented core from exploration wells (AS No. 1257162, IPC E 21 25/16, BI No. 34 - prototype). The core orientator consists of a core pipe with a drill and a crown and an adapter, an orienting sensor, a core explorer with a casing, and a core orienting device. The core-orienting device consists of a marking cutter mounted on the casing and an indenter installed in the drill bit and hidden in the holes of the casing in the form of a ring made of elastically deformable material, on which a replaceable washer from plastic-deformable material is placed.

Core orientator according to A.S. No. 1257162 has the following disadvantages:

the complexity of the design, the possibility of errors in determining the apsidal plane of the well due to the possible rotation of the crown at a certain angle when the drill is pulled during the process of interlocking and detaching the core from the bottom.

The task: to increase the accuracy of measuring the apsidal plane of the well and the reliability of the drill with a core-orienting device.

The 3 problem is solved as follows. Drill for selection - oriented core consists of a core pipe with an adapter, a drill bit with a core cutter and a core-orienting device. A circular groove is made on the inner surface of the upper part of the core core, in which the core-orienting device is placed. To place and fasten the annular tube of the device, the top end of the core core cutter is cut into sectors perpendicular to the circular groove. The device is made of a plastic deformable tube in the form of a ring, the free ends of which are connected by a sleeve. One end of the tube is rigidly fixed in the sleeve, and the second is able to move inside the sleeve by the amount of change in the gap of the longitudinal section of the core breaker. The tube is filled with a neutral, low-viscosity liquid, into which two solid balls of the same volume are freely placed, but with different densities, so that one of the balls drowns in the liquid and the second floats.

The invention is illustrated by drawings, which depict:

- figure 1 is a General view of the projectile in axial section;

- figure 2 - core drill with a core-orienting device (top view);

- figure 3 is a core breaker with a core-orienting device along section AA.

A drill for selecting an oriented core consists of a core pipe 1, a drill bit 2, an adapter 3, located, for example, in a drill core 4 (Fig. 1). On the inner surface of the core core at the upper thickened end face, a circular groove 5 is made, where a core-orienting device is inserted, which is a thin-walled tube 6 made of plastic-deformable material, for example aluminum (Figs. 2, 3). The tube is bent in the form of a ring, the ends of which are connected by the sleeve 7 so that one end of the tube is clamped rigidly in the sleeve, and the other (not shown) can move freely, allowing you to slightly change the diameter of the ring from the tube along with a change in the core core diameter due to its longitudinal section 8 at the core core 9. The upper end of the core explorer is cut into sectors 10 to the bottom of the circular groove 5. The formed walls of 11 sectors 10 around the groove have spring properties and allow you to insert and fix the tube 6 in the circular groove Dhu 5.

The pipe 6 is filled with a neutral low-viscosity liquid 12, where two solid balls of the same volume (diameter), but of different density, are freely placed so that the density of one ball, for example 13, is greater and the density of the other ball 14 is less than the density of the liquid.

Drill works as follows. After driving a predetermined interval of the well, the drilling process is stopped and the rotation of the projectile is stopped. In this case, the core breaker and orienting device remain on the core column 9 in the upper part of the drill bit 2. In the orienting device tube 6, the ball 13 with a density higher than the fluid density 12 will occupy the lower position in the well, and the ball 14 with a lower density will occupy the upper position. A straight (imaginary) line between them will correspond to the apsidal plane 15 of the well (figure 3). Then, when the projectile is raised by the inner cone of the crown, a thin tube 5 of plastic-deformable material is crushed and the core column 9 is jammed by balls 13, 14. After this, the core detaches from the bottom and the projectile rises from the well.

In the raised projectile, the drill bit is unscrewed, the core column is removed along with the core drill and the core-orienting device. Then visually through the slots of the kernel core sectors, the position of the desired balls is determined. For convenience, the balls are painted in different colors. Based on the position of the marks on the core and taking into account the inclinometric measurements in the well, the parameters of the elements of occurrence of rocks in the massif are determined using a core meter.

The proposed solution has the following advantages:

- the device is quite simple in design and operation;

- two balls are simultaneously involved in determining the apsidal plane of the well, which increases the accuracy of the measurement.

Claims (1)

A drill for selecting oriented core, consisting of a core pipe with an adapter, a drill bit with a core tapper and a core-orienting device, characterized in that the core-orienting device is an annular tube of plastic deformable material fixed in an annular groove on the inner surface of the top of the core core, the end of which is divided into sectors, with the free ends of the tube connected by a sliding sleeve, and the tube is filled with a non-aggressive liquid with a small by viscosity, while inside the tube two balls of solid material are freely placed, one of which has a lower density and the other is higher than the density of the liquid in the tube.

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