Hydraulic fracturing method for low-permeable formation with impermeable layer and water-bearing interlayer

FIELD: oil and gas industry.

SUBSTANCE: method involves landing of tubing string with packer to a well, packer seating, hydraulic fracture liquid injection by the tubing string with packer to a low-permeable formation, hydraulic fracturing of the low-permeability formation with further fracture fixation by injection of liquid carrier with propping agent via the tubing string, pressure relief in the well. Before tubing string landing to the well, water-bearing interlayer interval of the low-permeable formation is perforated to form perforation holes. Then at the wellhead the tubing string is filled upwards from the bottom with a plug, lower hole rows, packer, upper hole rows and additional packer. Inside the tubing string, a mobile bushing with radial channels is inserted to seal lower hole rows of the tubing string tightly in initial position and connecting the tubing string via upper hole rows and perforation holes to the ware-bearing interlayer. A seat is installed inside the mobile bushing, the mobile bushing and the seat are fixated in initial position against the tubing string by a differential shear element. The tubing string is landed to the well, packer and additional packer are seated in the well so as to shot water-bearing interlayer off tightly at two sides, upper water0bearing interlayer is isolated by injection and flushing of water isolation composition via the tubing string through upper hole rows to the water-bearing interlayer through perforation holes under pressure twice lower than hydraulic fracture pressure of the formation, process break is made for solidification of the water isolation composition, then a ball is dropped to the tubing string from wellhead, and overpressure is formed in the tubing string. First the shear element is destroyed, and under impact of overpressure above the ball, mobile bushing is shifted down along the tubing string to a stop against the tubing string plug, overpressure increase in the tubing string is continued, and the shear element is destroyed again. The seat is brought down to a stop against the plug under impact of overpressure above the ball. Upper hole rows of the tubing string are shut off tightly by the mobile bushing, and lower hole rows are connected to the tubing string by radial channels of the mobile bushing.

EFFECT: improved efficiency of hydraulic fracturing.

2 dwg

 

The invention relates to the field of oil and gas industry, in particular to hydraulic rupture of low-permeability formation containing a clay interbed with water-bearing zone.

The known method of hydraulic fracturing of carbonate reservoir (patent RU №2460875, IPC EV 43/26, publ. 10.09.2012, bull. No. 25), including the descent into the well of the column tubing - tubing with the packer and its subsequent landing, the descent into the tubing string of a column of flexible pipes - GT below the lower end of the tubing, the pumping podozrevayuschego cement through a flexible tube, conducting hydraulic fracturing of carbonate reservoir with bottom water. By the way the lower end of the GT is lowered to the level of the oil - water contact OWC, seal the space between the columns tubing and GT, fix podozrevayuschego cement by GT produced the isolation of bottom water in carbonate reservoir to fill the borehole from the bottom to the level of the KSS, and then rethermalized the space between the columns tubing and GT and lift the column of GT so that its lower end is at 1-2 m below the top of the carbonate reservoir, and then determine the total volume of fracturing fluid (Vg), seal the space between the columns tubing and GT and produce a fix in GT first portion of the fluid gap in the amount of 60-70% of total volume (Vgunder pressure not exceeding 25 MPa and at a speed not more 2 m/min, then the remaining volume of fracturing fluid pumped into GT in 3-5 cycles, alternating with the fix propping agent, which is used as a 25% inhibited hydrochloric acid, and the volume of acid is determined depending on the thickness of the productive part of the carbonate reservoir based on the volume of 0.2 m acid to 1 m thickness at each injection cycle, at the end of the last cycle of injection are prodavcu acid aqueous solution of a surfactant in the amount column GT with subsequent exposure of 1-2 hours, then remove the column GT from the tubing string and run well into operation.

The disadvantages of this method are:

- firstly, the limited capacity of the implementation of the method, as it applies only to the carbonate aquifer;

- secondly, the impossibility of carrying out insulation for water (aquifer zone), when water-bearing zone is located above the productive zone;

- thirdly, the duration of the method, associated with the need to descend into the tubing string columns GT below the lower end of the tubing, sealing (depressurization) of space between the columns tubing and GT, the movement of a column of GT inside the column tubing in the process of implementing the method;

- fourthly, the poor quality of the isolated aquifer zone, because as vodoizolyatsionnogo� material is cement-based, which is quite difficult to push deep into the aquifer zone.

The closest is a method of hydraulic fracturing (patent RU №2170818, IPC EV 43/26, publ. 20.07.2001 G., bull. No. 20), providing education in the reservoir with bottom water of a hydraulic fracture, the descent of the column tubing - tubing with the packer in the well, landing the packer. On the tubing string to produce the pumping of fracturing fluid from the formation with plantar water of a hydraulic fracture, then in the tubing to the bottom holes of the perforated interval is lowered a flexible pipe - GT, GT pumped for the proppant in the mixture with podozrevayuschim cement in a quantity sufficient to fill a mixture of the bottom of the crack to above oil-water contact with the filling of the crack in the bottom water zone (aquifer proplast) of the crack at the bottom of the oil-saturated zone (productive zone), while the column tubing serves liquid-sand carrier with proppant in the amount sufficient for fixing the upper part of the vertical cracks.

The disadvantages of this method:

- first, the fracturing is carried out before water isolation, which can lead to the formation of cracks across the thickness of the layer from bottom water to the roof, and there is no guarantee that when carrying out the subsequent waterproofing plantar chemiplast them completely you can isolate (to block the inflow of water in the productive part of the reservoir), which reduces the efficiency of hydraulic fracturing and causes rapid flooding of the reservoir for subsequent operation of the well.

- secondly, after the formation of cracks in the reservoir by injection of fracturing fluid into the tubing string is lowered GT and the operation takes a certain amount of time, during which the crack is partially closed, then produce both water-shut-off cement on GT a bottom part of the reservoir and the pumping of fluid-sand carrier along the annular space between the tubing and GT for sealing already started to close the cracks, which complicates the process of implementation of the method and reduces the permeability of the formed cracks;

- thirdly, it is impossible to carry out the isolation of the aquifer zone is in its location above the productive zone;

- fourthly, low quality insulation water bearing stratum, as the waterproofing material is cement, which is almost impossible to push deep into the aquifer zone;

- fifth, the duration of the method, associated with the need to descend into the tubing string columns GT below the lower end of the tubing, sealing (depressurization) of space between the columns tubing and GT, the movement of a column of GT inside the column tubing in the process of implementing the method.

Technically�and objectives of the proposal are to improve the efficiency and quality of hydraulic fracturing by eliminating the reduction of the permeability of fractures, formed in the process of hydraulic fracturing with the possibility of implementing the method when aquifer zone is above the productive zone, as well as reducing the duration of the method.

The technical problem solved by the method of hydraulic fracturing of low-permeability reservoir with impermeable bed and aquifer zone, which includes the descent of the column tubing with a packer into the well, landing the packer, pumping the fracturing fluid through the column tubing with a packer in low-permeability reservoir and the creation of a hydraulic fracture in low-permeability aquifer with the subsequent fastening of the crack injection on the column tubing of the fluid carrying the proppant, bleeding pressure from the well.

What is new is that before the descent of the column tubing - tubing in the well is perforated interval aquifer low permeability zone of a formation with the formation of the perforations, then at the wellhead, the tubing string from the bottom up equip cap, bottom rows of holes, the packer, the upper rows of holes and an additional packer and tubing inside install movable sleeve, equipped with radial channels, tightly overlapping in the initial position the lower rows of holes of the columns� tubing and informing the tubing string through the upper rows of holes and perforations aquifer zone, while inside the movable sleeve install the seat, a movable sleeve and the seat in the original position relative to the tubing string fixed differential shear element, lowering the tubing string into the well, put the packer and additional packer in the borehole so that they are hermetically cut off the water-bearing zone from two sides, produce the insulation of the upper aquifer zone is the fix and produvkoi waterproofing composition in the tubing string through the upper rows of holes in the aquifer zone through the perforations under pressure 2 times less pressure hydraulic fracturing, maintain technological pause for hardening waterproofing composition then the wells is discharged into the tubing string ball, create excessive pressure in the tubing string, this is done by first destroying the cutting element under the action of excess pressure above the ball moves a movable sleeve on the tubing string down until it locks into the recess of the tubing string, continue to improve the excess pressure in the tubing string and again destroy the cutting element, under the action of excess pressure above the ball seat is moved down until it stops at the plug, while the upper rows of holes tubing tightly clipped movable sleeve, and the lower rows of holes of the tubing string by means of radial channels stock�Noah sleeve communicated with the column tubing, then pumped fracturing fluid through the tubing string through the lower rows of holes of the tubing string in the perforations of the productive zone and produce in the productive zone is hydraulic fracturing with the formation of cracks, with subsequent attachment of the injection fluid carrying the proppant, after hydraulic fracturing of low-permeability reservoir vent pressure from the well and retrieve the tubing string.

The proposed method is as follows.

Fig.1 and 2 schematically presents the proposed method of hydraulic fracturing of low-permeability reservoir with impermeable bed and aquifer zone, where 1 production well; 2 - low permeable formation; 3 - impermeable bed (clay interlayer); 4 - productive zone (permeable Sandstone); 5 - water-bearing zone; 6 - perforation of the productive zone 4; 7 - perforated aquifer zone 5; 8 - column tubing; 9 - cover; 10 - lower rows of holes; 11 - packer; 12 - upper rows of holes; 13 - additional packer; 14 - movable sleeve, 15 - radial channels of the movable sleeve; 16 - seat, 17 - differential cutting element; 18 - ball; 19 - o-ring; 20 - valve; 21 - pressure line; 22 - hydraulic fracture.

Production well 1 (see Fig.1) revealed low-permeability layer 2 (the layer with impermeable�m interbed 3 (clay interlayer), below which is placed a productive zone (permeable Sandstone) 4 with low permeability (permeability (0.1 to 10)·10-3µm2), and higher water-bearing zone is 5.

Productive zone 4 producing well 1 through the perforations 6 is operated, for example, sucker rod pump (Fig.1 and 2 is not shown).

In operation, the flow rate at the production wells 1 quickly decreases, and therefore it should work on enhanced recovery of oil from low-permeability layer 2 producing well 1.

This purpose produce hydraulic fracturing - hydraulic fracturing of the productive zone 4 of the reservoir 2. This is removed from the well operational equipment (Fig.1 and 2 is not shown) and implement the proposed method as follows.

First, before the descent of the tubing string 8 (see Fig.1) in the borehole 1 on the column technological pipe pull the punch (Fig.1 and 2 not shown) of any known construction and is perforated interval aquifer zone 5 (see Fig.1) in the borehole 1 with the formation of the perforations 7. For example, using punch PCTL-M, manufactured by Neftekamsk machine-building plant (the town of Neftekamsk, Republic of Bashkortostan, Russia). Removed from the well 1 column technological pipe with a hammer.

Then at the wellhead the tubing 1 8 upwards �sysauth cap 9, the lower rows of holes 10, the packer 11 (next lower packer), the upper rows of holes 12, an additional packer 13 (hereinafter the upper packer).

From the condition of minimization of pressure losses in the process of implementing the method of the bottom 10 and top 12 rows of holes of the tubing string 8 is made, for example, in two rows and have a hole diameter of 12 mm, and are six holes in each row.

The inside of the tubing string 8 is installed movable sleeve 14, equipped with radial channels 15, sealed by means of sealing rings 19 overlap in the initial position the lower rows of holes 10 of the tubing string 8 and informing the drill pipe 8 through the upper rows of holes 12 and the perforations 7-aquifer zone 5. Inside the movable sleeve 14, set the saddle 16, and the movable sleeve 14 and the seat 16 is fixed in the initial position relative to the tubing string 8 shear element 17.

Pull the tubing 8 into the borehole 1 and put the upper 13 and lower packers 11 in the bore 1 so that they are hermetically cut off the water-bearing zone 5 from both sides.

As the packer is used, for example, a packer with mechanical axial installation P-YAMO (35 MPa) manufactured by scientific-production firm "Packer" (Oktyabrsky, Republic of Bashkortostan, Russian Federation).

At the wellhead 1 to the upper end of the tubing string 8 is set�t valve 20, which through the discharge line 21 tied with pump units (Fig.1 and 2 is not shown).

Produce insulation upper aquifer zone 5 injection waterproofing composition, such as resin, the column tubing 8 through the upper rows of holes 12 and the perforations 7 in the aquifer zone 5 pressure 2 times less pressure hydraulic fracturing.

For example, the pressure of hydraulic fracturing, as determined empirically, is 28 MPa. Then while isolating the upper aquifer, the injection of the resin is carried out under a pressure in the range of 28 MPa/2=14 MPa.

As the resin used, for example, acetonitrile resin, produced by TU 2228-006-48090685-2002, or urea-formaldehyde resin, produced by TU 6-06-59-89.

The use of resin can improve the quality of isolation of the aquifer, as the waterproofing material used cement, as in the prototype, and the resin which has a higher turnover and you can push deep into the aquifer zone 5.

Isolation aquifer zone 5 low-permeability layer 2 is produced before the fracturing poductive of the interlayer 4 low-permeability layer. As a result, the sole aquifer interlayer provides a reliable barrier precluding the development of cracks g�of kerasnya up ie the interval 5 aquifer zone 5, which minimizes flooding of the borehole 1 at the operation layer.

Withstand technological pause for hardening waterproofing composition, for example, 4 p.m.

After the isolation of the aquifer of the interlayer 5 with a wellhead dropped into the tubing string 8 ball 19 (see Fig.2). In the tubing string 8 over the ball 19 through the pump unit, for example CA-320, create excessive pressure.

As a result, first destroy the differential cutting element 17 in place of fixation of the movable sleeve 14 relative to the tubing string 8 and under the action of excess pressure above the ball 19 moves the movable sleeve 14 to the tubing string 8 down until it locks into the recess 9 of the tubing string 8.

Continue to increase the excess pressure in the tubing string 8 and re-destroy the differential cutting element 17 in place of fixation of the seat 16 relative to the movable sleeve 14 and under the action of excess pressure above the ball 19, the saddle 16 is moved downwards until it engages into the recess 9 of the tubing string 8, the upper rows of holes 12 of the tubing string sealingly through the sealing rings 19 are clipped movable sleeve 14.

The lower rows of 10 holes of the tubing string 8 by means of radial channels 15 of the movable sleeve 14 is communicated with the column tubing 8. Withstand technological pause for hardening waterproofing components�icii, for example, within 12 hours

Then the drill pipe 8 through the lower rows of holes 10 produce hydraulic fracturing of low-permeability reservoir 2 in the productive interval of the interlayer 4 with the formation of cracks in it 22 hydraulic fracturing and its mounting fix fluid carrying the proppant.

Hydraulic fracturing of low-permeability reservoir 2 in the productive interval of the interlayer 4 with crack 22 hydraulic fracturing and its mounting fix fluid carrying the proppant produced by any known technology, for example as described in patent RU No. 2473798 "Method of hydraulic fracturing in the well", IPC EV 43/26, publ. 27.01.2013., in bull. No. 3 or in the patent RU №2358100 "Method of hydraulic fracturing in the well", IPC EV 43/26, publ. 10.06.2009 G., bull. No. 16.

Reduced the duration of the method, due to the lack of necessity of application of the column of GT and its descent into the tubing string below the lower end of the tubing, sealing (depressurization) of space between the columns tubing and GT, displacement columns GT columns inside the tubing in the process of implementing the method, wherein the injection into the upper water-bearing zone and the lower productive zone is carried out by injection flow switching movement of the movable sleeve 14 with radial channels 15 relative to the tubing string 8 IU�do her top 12 and the bottom 10 rows of holes.

Consistent implementation of technological operations water shutoff aquifer of the interlayer 5 and the hydraulic fracturing of the productive zone 4 eliminates the reduction of the permeability of fractures produced during hydraulic fracturing of low-permeability layer 2, as hydraulic fracturing is performed after water shutoff.

The proposed method of hydraulic fracturing of low-permeability reservoir with impermeable bed and aquifer zone allows you to:

- to increase the efficiency of the method due to the preliminary isolation aquifer zone. As a result, the sole aquifer interlayer provides a reliable barrier precluding the development of a crack up at the interval aquifer zone, which minimizes flooding of the reservoir for subsequent operation of the well.

- eliminate the reduction in the permeability of the cracks formed in the process of hydraulic fracturing or fracking, as hydraulic fracturing is performed after water shutoff;

- implement isolation aquifer zone is in its location above the productive zone;

- to improve the quality of isolated aquifer zone, because as a waterproofing material used is cement, and a resin that has a higher fluidity, and can push deep � water-bearing zone;

- to reduce the duration of the method, as there is no need to use the columns of GT and its descent into the tubing string below the lower end of the tubing, sealing (depressurization) of space between the columns tubing and GT, displacement columns GT columns inside the tubing in the process of implementing the method.

Method of hydraulic fracturing of low-permeability reservoir with impermeable bed and aquifer zone, which includes the descent of the column tubing with a packer into the well, landing the packer, pumping the fracturing fluid through the column tubing with a packer in low-permeability reservoir and the creation of a hydraulic fracture in low-permeability aquifer with the subsequent fastening of the crack injection on the column tubing of the fluid carrying the proppant, bleeding pressure from the well, characterized in that before the descent of the column tubing - tubing in the well is perforated interval aquifer low permeability zone of a formation with the formation of the perforations, then at the wellhead, the tubing string from the bottom up equip cap, bottom rows of holes, the packer, the upper rows of holes and an additional packer and tubing inside install movable sleeve, equipped with radial channels, tightly overlapping in the original position�NII lower rows of holes of the tubing string and tells the tubing string through the upper rows of holes and perforations aquifer zone, while inside the movable sleeve install the seat, a movable sleeve and the seat in the original position relative to the tubing string fixed differential shear element, lowering the tubing string into the well, put the packer and additional packer in the borehole so that they are hermetically cut off the water-bearing zone from two sides, produce the insulation of the upper aquifer zone is the fix and produvkoi waterproofing composition in the tubing string through the upper rows of holes in the aquifer zone through the perforations under pressure 2 times less pressure hydraulic fracturing, maintain technological pause for hardening waterproofing composition then the wells is discharged into the tubing string ball, create excessive pressure in the tubing string, this is done by first destroying the cutting element under the action of excess pressure above the ball moves a movable sleeve on the tubing string down until it locks into the recess of the tubing string, continue to improve the excess pressure in the tubing string and again destroy the cutting element, under the action of excess pressure above the ball seat is moved down until it stops at the plug, while the upper rows of holes tubing tightly clipped movable sleeve, and the lower rows of holes of the tubing string by means of radial channels stock�Noah sleeve communicated with the column tubing, then pumped fracturing fluid through the tubing string through the lower rows of holes of the tubing string in the perforations of the productive zone and produce in the productive zone is hydraulic fracturing with the formation of cracks, with subsequent attachment of the injection fluid carrying the proppant, after hydraulic fracturing of low-permeability reservoir vent pressure from the well and remove the tubing.



 

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EFFECT: improving reliability of hydraulic formation fracturing and efficiency of fracture fixing.

4 dwg

FIELD: oil and gas industry.

SUBSTANCE: group of inventions is related to mining and may be used in a string or equipment for wells completion. The mechanical sliding sleeve (101) includes a guard (105) with openings for interconnection with fluid, the first adapter (103) connected to the sleeve guard and the second adapter (107) connected to the sleeve guard. An insulating bushing (201) is placed in the inner channel formed by the sleeve guard, the first adapter and the second adapter thus forming an opening (113) for interconnection with fluid. The insulating bushing slides along contact surfaces between the first adapter, the second adapter and the sleeve guard in between the open position when fluid comes through openings and the closed position when fluid passage is prevented through openings. The sealing element is coupled functionally to the sleeve guard, the first adapter, the second adapter and the insulating bushing in order to prevent fluid passage through openings when the sleeve is not in the open position and to insulate at least part of contact surfaces from contact with borehole fluids.

EFFECT: improving operational efficiency of the sliding sleeve.

15 cl, 15 dwg

FIELD: mining.

SUBSTANCE: fluid supply device features sensor of plugs (darts, balls, etc.) passing through tool. Actuator shifts tool insert after a preset number of plugs has passed through tool. Insert shift opens catcher in tool bushing. After next plug discharge, catcher connects to the plug in bushing so that fluid pressure applied to the plug installed in tubing string can move the bushing. Shifted bushing opens windows in tool, connecting tool channel to surrounding annular space, thus enabling treatment of formation interval adjoining well shaft to intensify flow. Actuator can use sensor of plugs passing through tool. Spring housed in tool can bend at approach to sensor when a plug passes tool, and sensor counts number of plug passes.

EFFECT: enhanced efficiency of multistage hydraulic fracture in one round trip operation.

32 cl, 25 dwg

FIELD: oil and gas industry.

SUBSTANCE: method includes simulating of formation and recording of data on borehole processes by a geophysical instrument run-in into the tubing string at a logging cable and self-contained instruments installed at the lower end of the tubing string. At that simulation of formation is made by breaking a breakable drain valve made of a brittle material of hemisphere shape and installed with a convex part downwards in the lower part of the tubing string; for this purpose a drill stem is fixed under the geophysical instrument and the geophysical instrument is run-in with the stem into the interval with speed sufficient to break the breakable drain valve. At that upper part of the tubing sting above the breakable drain valve is not filled with water and a packer is installed in tubular annulus at the level of the tubing string lower part.

EFFECT: increase of information content and reliability for borehole investigations; reduction of labour intensity, time consumption and equipment costs; possibility to use in wells with any producibility of the investigated formation.

1 dwg

FIELD: oil and gas industry.

SUBSTANCE: there is a description of pipe string for well completion installed in position neighbouring to zone or zones where hydraulic fracturing (HF) is to be performed and inflow is to be obtained. In preferable version its peculiarity concludes in valves with sliding couplings allowing implementation of at least two configurations; wide opening and opening of channel with filtering material located in it. Valve unit may have three positions where a position of complete closing is added to two above mentioned positions. After run-in-hole operation valves may be set to position of wide opening in any order required for HF. After completion of HF valves may be either closed or set to filtering position in a differentiated way to get inflow from the zone subjected to HF in any required order. There are various methods for valves actuation described. Pipe string may be provided with telescopic forcers providing HF if it is required to do string cementing. According to alternative version pipe string run in uncased well is just provided with holes for HF liquid passing through and outer packers for provision of HF in any required order.

EFFECT: proving HF in separated zones of formation in required order.

40 cl, 33 dwg

FIELD: oil and gas industry.

SUBSTANCE: multiposition device for selective switching over of flow through packer spindle between opposite directions contains: packer with packer spindle and sealing element designed so that spindle is retained in underground location when sealing element is in seating position; housing of crossflow coupling including components moved relative to each other and adjusted for its selective attachment near upper part of mentioned retained independently packer spindle, at that housing of cross-flow coupling when it is attached near upper part of packer spindle is able to generate relative movement providing opening and closing of channel on housing of cross-flow coupling.

EFFECT: reducing total length of device, orientation of device with higher accuracy.

13 cl, 6 dwg

FIELD: oil and gas production.

SUBSTANCE: down-hole valve includes housing with channel going through it, ball with through hole installed with the possibility of turning at its axis without longitudinal movement so that through hole coincides and not coincides with the said channel. The said ball axis is installed with the possibility of selective longitudinal movement in relation to the housing not depending upon the said turning.

EFFECT: increase of valve operation reliability via reliable keeping of open and closed position.

13 cl, 9 dwg

FIELD: oil and gas industry.

SUBSTANCE: selective well completion device includes a tube slide valve installed on the tube, the body of which is connected to the section of casing string, which is located opposite the productive formation and equipped with holes. Slide valve is equipped with two ring-shaped stops by means of which it is connected to the catch from time to time. Catch includes cylindrical housing with spring-loaded extendable cams and conical brace with a drive, which are located in it, and is connected by means of mechanical draft to the ground lifting mechanism attached to the ground power supply and control unit. At that, the device also includes independent electrical power supply located in the catch housing and made in the form of electrical accumulator or a set of electric batteries, at least two reed relays, similar number of signaling devices - electric lamps and at least three concentrically ring-shaped constant magnets installed in the well, as well as two radio contact devices mutually connected by means of radio on air. One of radio contact devices is located on the catch and equipped with the antenna in the form of electroconductive mechanical draft and connected to the independent power supply, and the other one is located on the ground surface and is connected via control unit to the ground power supply. Mechanical draft is flexible and made in the form of electroconductive rope. Drive of the brace includes electric heater equipped with thermostat, the working member located within its coverage and having the effect of shape memory in the form of straight-line wire from titanium nicelide and reverse element of the working member which is balanced and made in the form of a brace, and electric heat-insulating housing. At that, through the radio contact device fixed in the catch, the heater and each reed relay is separately connected to independent power supply, and by means of both radio contact devices the heater through the control unit and each reed relay separately through the control unit and one of the lamps are connected to the ground power supply.

EFFECT: enlarging functional capabilities of the device.

3 cl, 1 dwg

Downhole tool // 2304212

FIELD: oil production, particularly devices operating inside wells, for instance for circulation valve opening and closing, as well as for packer seating or removal.

SUBSTANCE: downhole tool comprises rod provided with member made as hollow sphere truncated from top and bottom and shaped as upturned cup. The cup bottom has facet extending along outer diameter thereof. Fishing head is arranged on sphere bottom from top thereof. The fishing head has dimensions within the range of sphere radius. Connected with inner sphere bottom part is stem having diameter less than sphere diameter. The stem is connected to the bottom through rod.

EFFECT: increased reliability and simplified technological operations to be performed.

2 dwg

Well whipped valve // 2068077
The invention relates to the oil industry and can be used in installations for the operation of wells, mainly with installations equipped with submersible pumps, for example, for well killing before they repair and drain the fluid from the raised tubing

Downhole tool // 2304212

FIELD: oil production, particularly devices operating inside wells, for instance for circulation valve opening and closing, as well as for packer seating or removal.

SUBSTANCE: downhole tool comprises rod provided with member made as hollow sphere truncated from top and bottom and shaped as upturned cup. The cup bottom has facet extending along outer diameter thereof. Fishing head is arranged on sphere bottom from top thereof. The fishing head has dimensions within the range of sphere radius. Connected with inner sphere bottom part is stem having diameter less than sphere diameter. The stem is connected to the bottom through rod.

EFFECT: increased reliability and simplified technological operations to be performed.

2 dwg

FIELD: oil and gas industry.

SUBSTANCE: selective well completion device includes a tube slide valve installed on the tube, the body of which is connected to the section of casing string, which is located opposite the productive formation and equipped with holes. Slide valve is equipped with two ring-shaped stops by means of which it is connected to the catch from time to time. Catch includes cylindrical housing with spring-loaded extendable cams and conical brace with a drive, which are located in it, and is connected by means of mechanical draft to the ground lifting mechanism attached to the ground power supply and control unit. At that, the device also includes independent electrical power supply located in the catch housing and made in the form of electrical accumulator or a set of electric batteries, at least two reed relays, similar number of signaling devices - electric lamps and at least three concentrically ring-shaped constant magnets installed in the well, as well as two radio contact devices mutually connected by means of radio on air. One of radio contact devices is located on the catch and equipped with the antenna in the form of electroconductive mechanical draft and connected to the independent power supply, and the other one is located on the ground surface and is connected via control unit to the ground power supply. Mechanical draft is flexible and made in the form of electroconductive rope. Drive of the brace includes electric heater equipped with thermostat, the working member located within its coverage and having the effect of shape memory in the form of straight-line wire from titanium nicelide and reverse element of the working member which is balanced and made in the form of a brace, and electric heat-insulating housing. At that, through the radio contact device fixed in the catch, the heater and each reed relay is separately connected to independent power supply, and by means of both radio contact devices the heater through the control unit and each reed relay separately through the control unit and one of the lamps are connected to the ground power supply.

EFFECT: enlarging functional capabilities of the device.

3 cl, 1 dwg

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