RU2251618C2 - Device for extracting sample out of borehole - Google Patents

Abstract

FIELD: well research, particularly means for drilling rock sample out of borehole in an airtight manner.

SUBSTANCE: device comprises case and hollow drill arranged in the case and having ring-shaped cutter. Stopper closing cartridge for sample receiving is kinematically linked with the drill by means of transmission mechanism. Transmission mechanism is formed as rotary drum with curved cut made in side surface thereof, deflecting finger and rotary arm. Deflecting finger slides in curved cut and is fixedly secured to drill body. Rotary arm is connected with the drum by one end thereof and with stopper by another end. Rotary arm is connected with stopper by means of mechanical couple including rod with plug. The stopper is arranged in cartridge lid and is made as rotary cylinder. Formed in the cylinder is through channel sized in accordance with the sample to be drilled out. Cylinder is provided with annular gaskets connected one to another by linear members. The rotary arm has an axis of rotation connected to device case.

EFFECT: simplified structure, increased reliability.

3 dwg

Description

The proposed device is intended for drilling a rock sample from the walls of the well and delivering them to the surface in the chamber under a pressure equal to the bottomhole pressure.

Known borehole sampler, which has a core drill bit, occupying an extended position for core sampling from the side wall of the well or a retracted position for storing the selected core. A special drive device provides core ejection from the bit into the receiving chamber and laying on the core of the separation ring gasket before extraction to the surface (US patent No. 5487433, E 21 V 25/02). The known device does not provide complete sealing of the drilled core.

A device of a core sampler of a drilling type is known, which allows rock samples to be taken from the walls of the well and raised to the surface in the chamber under a pressure equal to the bottomhole pressure. A distinctive feature of the core sampler is the core collection chamber, into which drilled samples are pushed through the connecting channel and the main valve after turning the drilling device through 90 °. After closing the core receiving chamber due to the action of the main valve, the pressure remains equal to the bottomhole and constant during the lifting of the core sample to the surface and transportation of samples in the chamber to the laboratory (US patent No. 4950844, Е 21 В 49/06).

The disadvantage of the design is its large dimensions. Through the use of a rotary drilling device, the diameter of the core sampler increases. The complexity of the hydraulic drive system for closing the core receiving chamber, as well as the low reliability of the sealing element, make the core sampler design unreliable as a whole.

The proposed device solves the problem of simplifying the design, increasing the reliability of the drilling process of the sealed core, as well as increasing the information content of the results.

The problem is solved in that in a device for selecting a sealed core from a well wall, comprising a housing and a drill with an annular cutter placed therein, a core receiving cassette with an overlapping plug, the plug is kinematically connected to the drill through a transmission mechanism, which is made in the form of a rotary drum with a curved cut on its side surface and a deflecting finger sliding in it, rigidly fastened to the drill body, and a pivot arm, which is connected to the drum with one end and with the other end closed with the help of a mechanical pair - a pin with a plug, while the overlapping plug is placed in the cover of the core receiving cassette and is made in the form of a rotating cylinder having a through channel commensurate with the core being drilled, in addition, the rotating cylinder is equipped with ring seals interconnected by linear elements, and the pivot arm has an axis of rotation associated with the body of the device.

In Fig. 1, a core sampler is shown in section, in Fig. 2 is a section along AA in the initial position, in Fig. 3 is a section AA in the case of core reception.

The device consists of a housing 1, which contains a kinematically connected electric motor, a gearbox (not shown in the diagram), a drill 2 (made hollow) with an annular milling cutter 3, designed for drilling a rock sample (core). On the lower plane of the drill 2, a finger 4 is rigidly fixed, which enters the curved groove of the drum 5. The drum 5 can rotate around the axis 6 and has a fork 7, in the groove of which includes a finger 8, mounted in a pivot arm 9, which can oscillate around the axis 10, and ending with a square tip 11. The tip 11 is articulated with a blocking plug 12 made in the form of a rotatable cylinder having a channel 13, consistent with the drill core. The plug 12 is located in the cover of the core receiving cassette 14 and sealed with a seal 15. The cartridge is attached to a removable cover 17, which is installed in the core 1 of the core sampler. The seal 15 is placed in the grooves in the body of the overlapping plug 12 and is made in the form of two rings 15, interconnected by linear elements 16. 18 is the pressure lever, 19 is the seal of the cover 17.

The device operates as follows: the device descends into the well, while the drill 2, the clamping lever 18 are in the initial position (Fig. 1), the channel 13 of the overlapping plug 12 is in the closed position (Fig. 2).

On command from the ground, in a core sampler lowered into the well for a predetermined interval, the electric motor is turned on, which, by kinematics, rotates the ring mill 3 and hydraulically rotates the clamp lever 18 so that it presses the core sample to the well wall.

The rotary cutter 3 by means of translational movement of the drill 2 is embedded in the wall of the well and drills a sample of rock of cylindrical shape (core).

With the translational movement of the drill 2, the finger 4 rotates the drum 5, which with a fork 7 rotates the lever 9 around the axis 10, while the overlapping plug 12 rotates around its own axis by 90 °, the channel 13 is set to the “open” position (figure 3), informing the cavity of the core receiving cassette 14 with the cavity of the device. The drilled core through the channel 13 enters the cartridge 14. After that, the electric motor of the device is reversed. The clamping lever 18 and the drill 2 are returned to their original position. At the same time, the drum 5, turning in the opposite direction, sets the channel 13 of the overlapping plug 12 to the “closed” position (figure 2). The device rises to the surface, while in the cavity of the cassette 14 baric conditions of the coring point are preserved.

Claims (1)

A device for selecting a sealed core from a well wall, comprising a body and a hollow drill with an annular cutter placed therein, a core receiving cassette with an overlapping plug, characterized in that the plug is kinematically connected to the drill by means of a transmission mechanism, which is made in the form of a rotary drum with a curved cut on its lateral surface and a deflecting finger sliding in it, rigidly fastened to the drill body, and a pivot arm, which is connected to the drum at one end and p to the other end a closing stopper using a mechanical pair - a pin with a plug, while the closing stopper is placed in the cover of the core receiving cassette and is made in the form of a rotating cylinder having a through channel commensurate with the core being drilled, in addition, the rotating cylinder is equipped with ring seals interconnected by linear elements, and the pivot arm has an axis of rotation associated with the body of the device.

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