RU2514009C1 - Device to determine water production intervals and to isolate them in boreholes of multihole horizontal wells - Google Patents

Abstract

FIELD: oil-and-gas industry.SUBSTANCE: device comprises the going-in string of hollow sealed pipes and logging instrument for well survey. Flow string used as said going-in string of hollow sealed pipes has bottom end with openings to accommodate blown valves while inner circular groove is made under holes in said flow string to receive split lock ring. Note here that hydraulic standoff device is arranged at bottom end of said flow string for it to get into open well of multihole horizontal well. Besides, this device is equipped with squeezing plug to slide over flow string, driven by fluid overpressure to destruct blown valves for opening of holes in flow string and locking by lock ring in said string under said holes. Logging instrument is lowered into flow string by stiff cable against the stop to squeezing plug.EFFECT: reliable operation, accurate determination of watered interval.3 dwg

Description

The invention relates to the oil and gas industry and may find application in the isolation of water inflows in open trunks of multilateral horizontal wells.

A device for shutting off the inflow of produced water in wells with horizontal bottom hole (patent for utility model RU No. 30518, IPC ЕВВ 33/12, published in Bulletin No. 17 dated 06/20/2003), including tubing pipes lowered on a string inflatable packers, while one of the ends of the tubing is plugged to provide simultaneous packing of the wellbore, and the other is connected to production equipment, and in the tubing made channels opposite the reservoir. At the same time, additional openings are made in the tubing opposite the inflatable packers, which are equipped with direct valves and a pressure relief mechanism for each inflatable packer. Check valves are installed in the channels of the tubing, and a deep pump is installed inside the tubing, the tubing is additionally equipped with centralizers, which are located in close proximity to the inflatable packers.

The disadvantages of the method are:

1) the complexity of the design associated with a large number of nodes and parts;

2) the device does not allow isolation of the water inflow interval, but only turns it off;

3) the device does not allow the shutdown of intervals of water inflow in the open trunks of a multilateral horizontal well.

A device for isolating formations in a well is also known (patent RU No. 2071545, IPC ЕВВ 33/12, published in Bulletin No. 1 of January 10, 1997), including upper and lower packers interconnected by pipes, each of which has a housing with a radial channel, a shell, forming an annular cavity with the outer surface of the housing, an annular cone and slips placed outside the housing with the possibility of interaction with each other, and check valves, while the device is equipped with a coupling mounted above the upper packer and connected to the housing by an adapter the second one is connected to the annular cone of the upper packer, a sleeve and stepped bushings, the smaller steps of which are oriented in opposite directions, the large steps are placed in the annular cavities, and the check valves and packer sealing elements are installed in the stepped sleeves placed between the shells and the ring cones, while the sub connected to the clutch by shear screws and made with the possibility of axial movement relative to the clutch until it stops against the annular cone of the upper packer.

The disadvantages of this device are:

1) the complexity of the design associated with a large number of nodes and parts;

2) low reliability associated with a complex principle of operation, and the device nodes are interdependent and operate in a specific sequence dependent on each other;

3) the device does not allow isolation in the open trunks of a multilateral horizontal well.

The closest in technical essence and the achieved result is a device for the study of horizontal wells (patent RU No. 2114298, IPC ЕВВ 47/01, publ. 06/27/1998 in bull. No. 18). The device comprises a geophysical instrument lowered into a horizontal well on a logging cable, providing a measurement of the flow rate and composition of the fluids in the well. Float elements are rigidly attached to the geophysical instrument, which are air-filled, airtight pipe sections. The average density of the float elements together with the geophysical instrument is less than the density of oil pumped out of the well. A pusher is attached to the float element, made in the form of a column of hollow sealed pipes, the average density of which is close to the density of oil pumped from the well. Inside the pusher tubes to the geophysical instrument are current-carrying conductors. A load motor is attached to the pusher, made in the form of a column of weighted pipes, through which a logging cable is connected, connected to the lead wires of the pusher. The length of the pusher corresponds to the total length of the horizontal and curved sections of the well. The load of the engine has such a mass that the force developed by the weight of the load of the engine when the device is lowered into the well is sufficient to push the geophysical instrument with float elements by means of a pusher to the bottom of the well.

The disadvantages of this device are:

1) low reliability associated with the possibility that the geophysical instrument will not reach the bottom of the well if the weight of the load-engine is insufficient, since it is impossible to determine in advance the resistance that occurs in the well during the descent of the device;

2) low accuracy of determining the flooded interval by a geophysical device, since during the study the geophysical device must be symmetrically in the flow of the well fluid, and due to the presence of float elements, it fluctuates in the fluid flow with a decrease in the density of the well fluid flow;

3) the device is designed to determine the intervals of water inflow in the horizontal wellbore, but does not allow to determine the intervals of water inflow in the trunks of a multilateral horizontal well.

The technical task of the proposal is to increase the reliability of the device and the accuracy of the determination of waterlogged intervals in the open hole of a multilateral horizontal well by conducting selective geophysical surveys followed by isolation of the waterlogged intervals of the well, as well as by placing the geophysical instrument directly in the fluid stream.

The stated technical problem is solved by a device for determining the intervals of water inflow and their isolation in the open trunks of multilateral horizontal wells, containing a string of hollow sealed pipes lowered into the well and a geophysical instrument for conducting geophysical surveys.

What is new is that at the lower end of the column of hollow sealed pipes, which are used as a tubing string, holes are made, knock-off valves are installed in the holes, and below the holes in the tubing string there is an inner ring sample, in which a split a retaining ring, while at the lower end of the tubing string, below the holes, a hydraulic diverter is installed, which ensures that a multi-hole horizontal well gets into the open trunk In addition, the device is equipped with a squeeze plug that can move along the tubing string under the influence of excess liquid pressure with the possibility of breaking the knockout valves with opening holes in the tubing string and fixing the retaining ring in the tubing string below the holes , the geophysical instrument is lowered into the tubing string by means of a rigid cable, all the way into the squeeze plug.

Figure 1, 2 and 3 shows the proposed device in the process.

In a multilateral horizontal well 1, to study its open boreholes, for example 1 ', 1 ", 1''' (Fig. 1), a device is used that is lowered into the well on a string of hollow sealed pipes, which is used as a string of tubing 2 (hereinafter referred to as a pipe string) with openings 3, 3 '... 3 ⁿ at the lower end. As a pipe string 2, a tubing string of 73 mm diameter may be used according to GOST 633-80. For example, at the lower end of a pipe string 2 perform three holes 3, 3 ', 3 "(figure 1 shown conventionally) with a diameter of 18 mm In the holes 3, 3 ', 3 "of the pipe string 2, respectively, there are three knocking valves 4, 4', 4" (shown in Fig. 1 conventionally) at an angle of 120 ° relative to each other, made of bronze grade BrAMts9-2.

At the lower end of the pipe string 2 (Fig. 1), below the holes, a hydraulic diverter 5 is installed, equipped with a rod 5 'and a nozzle 5 "with a hole at the bottom. The rod 5' of the hydraulic diverter 5, under the action of excess liquid pressure in the pipe string 2, allows the column to enter pipes 2 in any of the open boreholes 1 ', 1 "... 1 ^{n of a} multilateral well 1, for example, into an open borehole. The nozzle 5 "with the hole of the hydraulic diverter 5 provides flushing during tripping operations of the pipe string 2.

As a hydraulic diverter 5, devices widely used by OAO Tatneft for flushing and acid treatments of multilateral wells described in patents RU No. 2318111, IPC ЕВВ 23/00, publ. 02/27/2008, or No. 2318112, IPC Е21В 23/00, publ. 02/27/2008 in bull. No. 6.

The device is equipped with a squeezing plug 6 (Fig. 2), which can be moved along the pipe string 2 under the influence of excessive liquid pressure and the destruction of the knock-off valves 4, 4 ', 4 "with the opening of holes 3, 3', 3" in the pipe string 2.

There is the possibility of subsequent fixation of the squeezing plug 6 with a split retaining ring 7 (Figs. 1 and 2) installed in the inner annular sample 7 '(Fig. 1), made in the pipe string 2, below the holes 3, 3', 3 ", and tight cutting off the hydraulic diverter 5 from the pipe string 2.

To determine the interval of water inflow, the device is equipped with a geophysical device 8 (figure 2). They use a geophysical device 8 of any known design, for example, a complex modular type device of the GDI-7 brand manufactured by Tatneftegeofizika-Universal LLC (Tatarstan Republic, Bugulma), designed to conduct hydrodynamic studies in open boreholes of horizontal wells. Using this device, geophysical studies are carried out, for example, thermometry and debitometry (inflow), determining the water-cut interval of the open hole 1 '(Fig. 1) of the multilateral horizontal well 1 while moving the geophysical instrument 8 along the open well 1' of the multilateral horizontal well 1.

The geophysical instrument 8 (Fig. 2) is equipped with a rigid cable 9, through which it descends from the wellhead (not shown) of the well through a pipe string 2 (Fig. 2) into a multilateral horizontal well 1.

In the horizontal section of the well, the geophysical instrument 8 is pushed along the pipe string 2 to the hydraulic deflector 5 with a rigid cable 9 with the force generated by unwinding the drum of the geophysical elevator (not shown in FIGS. 1, 2, 3), on which the hard cable 9 is wound, due to its rigidity allows you to effectively deliver the geophysical instrument 8 into a horizontal well.

As a rigid cable 9, for example, a cable of variable cross-section of grade KL 3-160 / 230-900a (with a diameter of 22-28 mm) or a cable of constant cross-section (diameter 28 mm) of grade KG 3 × 0.75-150-150 Oa, manufactured by CJSC GISpribor-M (Russia, Pskov, Almaznaya St., 3).

The flapper valves 4 are designed to create a message of the internal space of the pipe string 2 with the space of any of the open shafts 1 ', 1 ", 1' '', for example, with the open trunk 1 ', a multi-hole horizontal well 1. The flapper valves 4 are destroyed after the device falls into the set open trunk, then determine the intervals of water inflow and their isolation through the holes 3 of the destroyed knockdown valves 4.

The device operates as follows.

At the wellhead, the proposed device for determining the intervals of water inflow and their isolation in the open trunks of a multilateral horizontal well 1 is assembled (Fig. 1). For example, it is necessary to determine the interval of water inflow and isolate in the open hole 1 'of a multilateral horizontal well 1 with a known bottom of 1150 m.

A device for studying open shafts of a multilateral horizontal well on a pipe string 2 is lowered into a multilateral horizontal well 1 until the hydraulic diverter 5 is opposite the entrance to the open hole 1 '(Fig. 1), for example, in the interval of 950 m. During the descent the pipe columns 2 flush the multilateral well 1 through the 5 "nozzle with the hole of the rod 5 'of the hydraulic diverter 5. Flushing the well 1 during the descent of the device eliminates its blockage with sludge.

Then, from the mouth of a multilateral well horizontal well 1 using any known pump, for example, a cementing unit of the CA-320 brand, the process fluid is pumped into the pipe string 2, for example, fresh water with a density of 1000 kg / m ^{3 is used} and an excess liquid pressure is created, which through the inner space 10 (figure 2) of the pipe string 2 is transmitted into the inner space (not shown) of the hydraulic deflector 5.

As a result, the stem 5 'of the hydraulic diverter 5 is rotated towards the open barrel 1'. Further, without reducing the excess pressure in the pipe string 2, the pipe string 2 is continued to descend into the open hole 1 ′ of the multilateral well 1 until it stops in the bottom 11 (for example, in the range of 1150 m) of the open hole 1 ′ of the multilateral well 1.

This technological operation allows you to determine the exact location (hit) of the pipe string 2 in a given open hole 1 ', since all open shafts 1', 1 "... 1" "of the multilateral well 1 have different values of the faces.

Raise the string of pipes 2 up until the hydraulic diverter 5 is in the interval of tapping 12 (Fig.2) of the open barrel 1 '(Fig.1), while the hydraulic diverter 5 remains in the open barrel 1'. For example, the length A of the hydraulic diverter 5 (Fig. 1) is 2 m. Then the hydraulic diverter 5 is placed in the interval of tapping 12 at a distance of 950 + 2 = 952 m. Knowing the bottom hole 1 (1150 m), determine the height by which raise the pipe string 2: 1150-952 = 192 m. Thus, the pipe string 2 is raised up to 192 m.

From the mouth of a multilateral hole 1, a squeezing plug 6 is installed in the pipe string 2 (Fig. 2), which is pushed through the inner space 10 under the influence of the excess pressure created by the pump unit CA-320 pumping a technological fluid, for example fresh water with a density of 1000 kg / m ³ pipe columns 2. Slug plug 6 moves over the pipe string under the influence of excess liquid pressure 2. When overpressure, for example 10 MPa, is reached, knock-off valves are destroyed 4. Openings 3 in pipe string 1 are opened for access downhole fluid inside the pipe string 2, while the squeeze plug 6 moves further along the pipe string 2 and is fixed in it below the holes 3 using a retaining ring 7 located in the pipe string 2 below the holes 3. Then into the pipe string 2 (figure 2) on the hard cable 9 lower the geophysical instrument 8.

A rigid cable 9 pushes the geophysical device 8 through the inner space 10 of the pipe string 2 all the way into the squeeze plug 6. In this case, the geophysical device 8 is opposite the openings 3 of the pipe string 2, through which liquid is supplied to the pipe string 2 to study the open trunk 1 ′.

By moving the pipe string 2 from the cut-off interval 12 (952 m) to the bottom 11 (1150 m) of the open hole 1 ', for example, the water-cut interval (not shown) in the open hole 1' (Fig. 2) of the multilateral well 1 in the range of 1072- 1094 m. On a rigid cable 9, a geophysical instrument 8 is removed from the pipe string 2.

Isolation of the open hole 1 '(Fig. 3) of a multilateral horizontal well 1 in the interval 1150-1072 m is carried out by pumping through the pipe string 2 insulating material, for example microcement (ultra-thin ultracement), produced by NPO Polytsell CJSC (Vladimir) according to TU 5739-019-56864391-2010. For this, microcement is closed in fresh water with a density of 1000 kg / m ³ with a mass ratio of 2: 3, respectively, and the resulting solution is pumped into the pipe string 2.

Then, at the same time, insulating material is forced through the holes 3 of the pipe string 2 into the open hole 1 'of the multilateral horizontal well 1 and the pipe string 2 is lifted to the upper section of the waterlogged interval (1072 m). Thus, the open hole 1 '(Fig. 3) of the multilateral horizontal well 1 is isolated.

To determine the watering interval and its isolation in another open hole 1 ", ... 1 ^{n of a} multilateral well 1, for example, in an open hole 1", a device is assembled at the wellhead on a pipe string 2, as shown in Fig. 1. Repeat the technological operations performed in the study of the open barrel 1 '.

The proposed device provides improved reliability and accuracy of determining the waterlogged interval in the open trunks of a multilateral horizontal well, while the geophysical instrument is located directly in the flow of the fluid due to its joint movement with the pipe string along the open well of the multilateral horizontal well, and the hard cable transfers data to the wellhead measurements in dynamics, which allows more accurately determine the watering intervals, and then isolate them ju in the open trunks of a multilateral horizontal well.

Claims (1)

A device for determining the intervals of water inflow and their isolation in the open trunks of multilateral horizontal wells, containing a string of hollow pressurized pipes lowered into the well and a geophysical device for conducting geophysical surveys, characterized in that at the lower end of the string of hollow pressurized pipes, which use a pumping string compressor pipes, holes are made, knock-off valves are installed in the holes, and below the holes in the tubing string, an internal An end sample, in which a split retaining ring is installed, while at the lower end of the tubing string below the holes a hydraulic deflector is installed to allow a multilateral horizontal well to enter the open bore, in addition, the device is equipped with a flow plug that can be moved along the pump string compressor pipes under the action of excess liquid pressure with the possibility of destruction of the knocking valves with the opening of holes in the string of tubing and fi casing by the retaining ring in the tubing string below the holes, the geophysical instrument is lowered into the tubing string by means of a rigid cable until it stops in the squeeze plug.

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