RU2232873C1 - Device for secondary drilling-in of productive stratum - Google Patents

Abstract

FIELD: oil-and-gas production industry; secondary drilling-in of productive stratum to depth of penetration of filter of drilling mud, plugging-back and other technological fluids.

SUBSTANCE: proposed device includes tubular housing with drilling unit inside it, drill, drill flushing unit, mechanism for securing housing to wall of well bore, cassette with drill and drilling bushes for adding the length of drill and suspension of housing in form of logging cable. Drill is made in form of hollow rod with mill at the end. Drilling unit is provided with elastic diaphragm having central hole whose diameter is lesser than diameter of drilling bush rotating in synchronism with bush during its operation. Mechanisms for securing the housing are mounted above and under drilling unit symmetrically to it. Drill and drilling bushes are pressed from below by means of spring. Cassette is built in lower portion of device and partially located in drilling unit for alignment of axes of drill and spindle of drilling unit. Mill has ellipsoid section.

EFFECT: simplified construction; enhanced reliability.

2 cl, 3 dwg

Description

The invention relates to the oil and gas industry, and in particular to devices used in the secondary opening of productive formations by drilling to a depth of penetration of the filtrate of drilling, grouting and other polluting formation fluids and more.

Known drilling downhole drill [1], containing a cylindrical body, the housing suspension in the form of a wireline cable, an oil pump, a retractable drill, a drill extension mechanism for drilling and a mechanism for fixing the perforator body to the well wall.

Its disadvantage is that, due to its design features, it cannot create channels by drilling the necessary depth, to the depth of penetration of polluting liquids into the formation.

It is also known a device for the secondary opening of the reservoir by drilling [2], including a tubular body, inside which are placed the nodes of rotation, feed the drill, made in the form of a hollow rod with a cutter at the end, the upper and lower fixing mechanism of the body to the wall of the wellbore, a cassette with placed in it with bushings for building up the drill as it penetrates to the length of one sleeve and the housing suspension in the form of a wireline cable.

This device is in technical essence closer to the proposed one and can be adopted as a prototype.

Its disadvantages are design complexity, low reliability, there are cases of failure of the drill feed units and the supply of bushings from the cartridge due to jamming of the drill, since it is possible that chips and cuttings get into the spindle area and cartridge. In addition, the risk of breakage of the cutting tool-milling cutter when the drill leaves the column due to the elastic deformation of the device body and its deviation from the axis of the well due to the force developed by the feed unit during drilling due to the significant distance of the fixation points of the device in the well relative to drill, which leads to a sharp increase in the supply of drill at the time of its exit from the casing and jamming.

The objective of the present invention is to simplify the design of the device, increasing its reliability in operation by fixing the device as close as possible to the spindle.

The problem is solved by the described device containing a tubular body, with a drilling assembly placed therein for rotation and feeding the drill to the well wall, a drill flushing device, a drill made in the form of a hollow rod with a mill on the end, mechanisms for fixing the case to the walls of the wellbore, cassette with a drill and drill sleeves placed in it to build it up and a housing suspension in the form of a wireline cable.

What is new is that the drilling unit is equipped with an elastic diaphragm with a central hole with a diameter smaller than the diameter of the drill sleeve, synchronously rotating when working with a drill passed through its hole, preventing clogging of the spindle’s internal movement zone with spent metal chips and cuttings, while body fixings are installed above and below the drilling unit as close as possible to it, and the cassette with the drill and drill sleeves located in it, preloaded from below by a spring, is installed on the bottom of the device and partially placed in the drilling unit with the possibility of alignment of the axis of the drill and the axis of the spindle of the drilling unit, and the drill cutter is made in the form of an ellipse in cross section.

Another difference is that it is equipped with an electronics unit, an electrically connected system for monitoring the drilling process and recording the results on a computer.

Patent research on novelty, as well as on inventive step, was carried out according to the patent fund of the TatNIPIneft Institute for a depth of 20 years. The search results showed that objects of a similar purpose and characterized by such a combination of essential features, like the proposed one, were not found. Therefore, we can conclude that the claimed object meets the criteria of "novelty" and "inventive step".

The presented drawings explain the essence of the invention, where Fig. 1 schematically depicts the inventive device in operation, lowered on a wireline opposite the reservoir, a general view, in partial section, in Fig. 2 - a reference conductor with a drill, a fragment of the cassette and drill sleeves, in partial section; figure 3 is a view of A, the moment of exit of the drill cutter from the conductor through an elastic diaphragm-seal.

The device comprises a composite tubular housing 2 (see FIG. 1) launched on a logging cable 1, which is a suspension, with interconnected mechanical, hydraulic and electrical systems located inside the housing, including a drilling unit 3 for rotation and supply of the drill string with a drill 4, flushing unit (flushing unit not shown), fixing mechanisms 5 and 6 upper and lower, respectively, with anchoring elements 7 and 8 for fixing the body 2 to the wall of the wellbore 9, installed above and below the drilling unit in the maximum possible distance awns thereto and disposed symmetrically with respect thereto; a cassette 10, located in the lower part of the housing, with drill sleeves 11 for building a drill string with a drill 4, pressed from below by a spring 12 to push them one at a time into the support conductor 13; drilling unit 3; electric drive 14; an electronics unit 15, electrically connected to a system for monitoring the drilling process and recording results on a computer (computer not shown). The drill is made in the form of a hollow rod 16 with a mill 17, the cutting part of which is made in the form of an ellipse (see Fig. 3) in cross section, and a connecting element is made at its other end, for example, in the form of a coupling 18 for building it with drill sleeves 11. The drill sleeves 11 are made of the same size, the end sections of which are in turn made in the form of a nipple 19 and a coupling 20. The rotating conductor 21 of the drilling unit is provided with a diaphragm 22 with a central hole 23 made of an elastic material that insulates the internal movement zone of the spindle 24 (see Fig. 2 and 4) about t getting there and clogging with metal shavings and particles of cuttings. The elastic diaphragm 22 is installed in an annular sample of a rotating conductor held by a nut 25 with the ability to synchronously rotate together with the drill and, therefore, the drill sleeves passing through its central hole, which is made with a diameter smaller than the diameter of the drill sleeves for a tight girth of their outer surface .

The inventive device operates as follows. It is lowered into the well on the logging cable 1 in the interval of the reservoir 26 (see Fig. 1) and power is supplied from the ground control panel to its electric motor via the cable, thereby putting it into operation. In this case, the rotation of the shaft of the electric drive motor is transmitted to the drive shaft of rotation and supply of the drill assembly of the drilling unit, at the same time, the anchoring elements 7 and 8 of the device fixing mechanisms 5 and 6 are released, which, pressing against the well wall, fix the device in a stationary state. At the same time, the pump for the flushing unit starts to work (the flushing unit and the pump are not shown). The spindle 24 of the drilling unit 3 (see figure 2), moving rotationally-translationally engages with the clutch 16 of the cutter 17 and moves it to the borehole wall until it stops, the drilling process begins. In this case, the drill first passes through the wall of the casing pipe and then goes deeper into the formation rock. After deepening the drill for its entire length, the spindle returns to its original position, freeing up space for the drill sleeve in the conductor 13, which is fed there under the action of the compressed spring 12 of the cartridge 10. The spindle, again moving rotationally-translationally, first screwes it into the coupling 18 of the drill 16, and further, the deepening process continues until the drill deepens to the length of one sleeve. Next, the cycle repeats. The process of using drill sleeves in the organization of the drill string during drilling of the reservoir is displayed and archived through the control panel on the IBM PS. After all drill sleeves exit the cassette, the operator of the control panel turns on the engine reverse, in which the upper latch (latch is not shown) returns the anchoring elements 7 to their original position, as a result of which the coupling 27 is activated and the motor shaft starts to rotate idle. After turning off the engine, the device is ready to rise. When lifting, under a tensile force, the anchoring elements 8 of the lower locking mechanism occupy a position that does not interfere with the lifting of the device from the well.

To perform the drilling of the next channel before the device is lowered into the well, the freed cartridge from the bushings is removed, and another one with charged drilling bushings is installed in its place.

The technical and economic advantage of the proposal is as follows.

The device proposed for protection by the patent has increased reliability in operation, due to the elimination of spent metal chips and drill cut particles getting into the inner travel zone of the spindle, a more successful arrangement of the device fixing mechanisms and the implementation of the cutting part of the cutter of an optimal design. The design of the invention is significantly simplified in comparison with devices of a similar purpose, and therefore, it is metal-intensive and compact. Preliminary field tests conducted in the fields of OAO TATNEFT gave positive results.

Sources of information

1. RF patent No. 2054877, 6 E 21 B 43/44, BI No. 11, 1996

2. RF patent No. 2182961, 7 E 21 B 43/11, BI No. 15, 2002 (prototype).

Claims (2)

1. A device for the secondary opening of the reservoir by drilling, including a tubular body with a drilling unit located therein for rotation and feeding the drill to the well wall, a drill made in the form of a hollow rod with a mill on the end, a drill flushing unit, housing fixing mechanisms to the barrel wall wells, a cassette with a drill and drill sleeves located in it for building it up, and a housing suspension in the form of a wireline, characterized in that the drilling unit is equipped with an elastic diaphragm with a central hole with a diameter smaller than the diameter of the drill sleeve, synchronously rotating when working with a drill passing through its hole, preventing clogging of the inner spindle movement area with spent metal chips and cuttings, while the housing fixing mechanisms are installed above and below the drilling unit as close to it as possible and are located relative to it symmetrically, and the cassette with a drill and drill sleeves located in it, preloaded from below by a spring, is built into the bottom of the device and partially placed in the drilling unit with awn ensure concentricity of the axes of the drill and the drilling spindle unit, wherein the milling drill is in the form of an ellipse in cross section. 2. The device according to claim 1, characterized in that it is equipped with an electronics unit electrically connected to a system for monitoring the drilling process and recording the results on a computer.

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