SU1737098A1 - Dual core barrel - Google Patents

Abstract

Use: core drilling. SUMMARY OF THE INVENTION: A double column projectile comprises a column tube and a cap, movable within it, having an internal cavity and a chamber above the cavity. A core bearing tube is installed inside the cavity of the cap, connected by a rod to a piston inside the chamber and spring-loaded relative to the cap. The throttling elements on the head and core pipe when pumping washing fluid cause high-frequency oscillations of the head and core receiver. 1 hp f-ly, 1 ill.

Description

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The invention relates to the mining industry and can be used in the drilling of wells with coring.

Known are double-core shells containing a rock-destroying tool, outer and core-receiving pipes with channels interacting with each other by means of a spring.

The disadvantages of the known projectiles are the low mechanical speed of drilling and, as a result, the inevitable loss of core from scouring with a stream of washing liquid.

Also known is a double core, containing a core pipe with an upper inner protrusion, a core rock-breaking tool with an internal annular protrusion connected to the core pipe, and a core receiver with a shoe, non-return valve and branch ducts placed inside the core pipe with the option a longitudinal displacement between the protrusions of the core tube and the rock cutting tool.

A disadvantage of this device is the low core yield due to the intense wear of the leading chisel of the core tube.

The purpose of the invention is to increase the core yield.

An increase in the core yield is achieved by improving the conditions for the formation and transportation of the core in the cavity of the core-receiver tube. The upward flow of the washing liquid and the longitudinal vibration of the tube. In addition, when using the proposed device, the mechanical speed of drilling increases due to the imposition on the bit of additional destructive shock loads.

The goal is achieved by the fact that the well-known dual-core projectile containing a core tube with an upper

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an internal protrusion, a core rock-breaking tool with an internal annular protrusion and a core receiver tube with a shoe, a check valve and branch ducts connected to the core tube and placed inside the core pipe with the possibility of longitudinal displacement between the protrusions of the core pipe and the rock-destroying tool are provided with a spring-loaded relatively core core a pipe with a cap with an internal cavity and a chamber above the cavity with a piston placed in it, while the core-receiving pipe is located inside wipe the cavity of the head cover, the piston is connected by a rod to the core-receiving tube, the head cover is made with two annular grooves on the outer side surface, and the core pipe - with an internal ring throttling protrusion located in the interval between the annular grooves of the head cap, the internal cavity of the head cap is made cononic with downward the base

The drawing shows a schematic diagram of the proposed double core projectile.

The double core projectile contains a core 1 and a core tube 2 pipe, a rock-destroying tool in the form of a column bit 3 with internal stepped protrusions 4 and 5 and channels 6 for the washing liquid. The column tube 1 has an inner annular protrusion 7 and in its cavity there is a cap 8 with annular channels 9 and 10 and a protrusion 11 between them on the outer side surface and the centralizer 12 remote from the protrusion 11 by a predetermined distance. In a conical base down the cavity 13 of the headrest 8 is placed core tube 2, interacting with it by means of springs 15 and piston 16 having channels 17 placed in chamber 14, and core tube 2 connected to upper blind end.

Core lifter pipe 2 ends with shoe 19, and headgear 8 with shoe 20, communicating respectively with protrusions 5 and 4 of bit 3, and the average diamtr of shoe 20 is equal to the average diameter of the circle on which the flushing channels 6 of bit 3 are placed, and the outer diameter of shoe 19 is the inner diameter of the protrusion 4. At the end of the shoe 20 there are radial channels 21, and the protrusion 5 of the bit 3 is equipped with a core 22. In the upper part of the core receiver pipe 2, a check valve is located under the blind end.

23 and inclined outwards and to the bottom of the channel 24, open into the cavity of the headband 8. In the upper part of the cavity of the core pipe is placed thrust annular

the protrusion 25.

The device works as follows.

When lowering the projectile into the borehole, the cap 8, under the influence of

0, the flushing fluid occupies the uppermost position, resting against the ribs of the centralizer 12 against the protrusion 25.

5 snare through the annular space, as well as through the central channel of the core tube 2. 2. The valve 23, channels 24 and the cavity of the headgear 8, moving it upwards. Further, through the radial channels 21 of the shoe 20, the space between the cap of the head 8 and the core pipe 1, the flushing fluid flows into the central channel of the drill pipe string connected to the upper part of the core pipe 1.

5 After placing the projectile on the bottom, the device is driven into rotation by the drill pipe and the flushing fluid is supplied to the bottom. In this case, the core-receiving tube 2 rests on the shoe 19 into the protrusion 5

0 of the rock-destructive tool 3, and the cap 8 rests on the spring 15 and hangs over the upper end of the core-receiving tube 2. The pressure of the flow of flushing fluid acting on the cap

5-8, the latter is moved downward, compressing the spring 15 and abutting the protrusion 4 of the bit 3 with the shoe 20 o. At the same time the flushing fluid flows through the channel 9, the protrusion 7 on the core pipe 1 mines and reaches

0 through the channels of the bit 3. At the moment of impact of the shoe 20 on the protrusion And part of the channels 6 overlaps with the Iashmak 20 and the flushing fluid through the radial channels 21 of the Shoe 20 flows to the chamber 14 of the head

5 to 8, filling it through the channels 17 in the piston 16. By increasing the pressure of the washing liquid in the chamber 14 and by means of the spring 15, the cap rises above the upper end of the core-receiving tube 2. The washing fluid flows to the bottom through the channels 6, the pressure in the chamber 14 drops and the cap 8 re-shifted downward under the pressure of the downward flow of washing liquid.

5 When the headgear 8 moves, the core-borne pipe 2 also oscillates along the axis, but with a smaller amplitude, and strikes the shoe 19 against the protrusion 5. The oscillations of the conical cavity of the headband 8 near the inclined holes 24 create an ejection effect in the upper part of the core core cavity 2, reinforced by its vibrations, stabilizing the upward flow of the washing liquid in its cavity. The upward flow of washing fluid in the cavity of the core-receiver tube 2 improves the conditions for core formation, due to which its output increases. High-frequency longitudinal oscillations of the core-receiver tube 2 contribute to the movement of the core deep into its cavity, which also contributes to increasing its output. Impact loads on the rock-destroying tool 3 provide an increase in the mechanical drilling rate. It also allows for increased core yield, as a result of which the effect of harmful parameters on the core is reduced. The drilled core during lifting of the projectile is held in the cavity of the pipe 2 by the core holder 22.

Claims (2)

Claim 1. Double core projectile containing a core pipe with an upper inner protrusion, a core rock-breaking tool with an internal annular protrusion connected to the core pipe and a core tube with a shoe, a check valve and branch ducts located inside the core pipe with the possibility of longitudinal displacement between the projections core pipe and rock cutting tool, characterized in that, in order to increase the core yield, it is provided with a spring-loaded relatively core receiver A pipe with a cap with an internal cavity and a chamber above the cavity with a piston placed in it, while the core-receiving tube is located inside the cavity of the cap, the piston is connected to the core with a core tube, the head-cap is made with two annular grooves on the outer side surface, and the column tube - with the inner ring throttling protrusion located in the interval between the annular grooves of the head. 2. The apparatus according to claim 1, characterized in that the internal cavity of the headrest is made conical with the base oriented downwards.