RU2414586C1 - Procedure for isolating operations in well and packer equipment - Google Patents

Abstract

FIELD: gas-and-oil producing industry.

SUBSTANCE: procedure consists in lowering string with drillable packer on adjusted hydraulic tool, in its installation in specified interval of well and in pumping required volume of material into under-packer space. Further, the adjusted hydraulic tool is retracted from the packer; the overlying interval is processed under pressure or the production string is pressurised for pressure tightness omitting condition time for hardening previously pumped material. The packer has upper and lower dividers. A mechanism of packing fixation consists of catches, on internal surface of which there are teeth interacting with threads on external surface of a packer mandrel. Between an upper cone and a sealing element of the packer there is arranged a bearing sleeve with double-sided saw-like projections and recesses entering response slots of an upper cone and the sealing element; a lower end of this element also has saw-like projections entering response slots of the lower cone.

EFFECT: pumping material in two intervals above and under packer regardless of direction and value of pressure drop.

3 cl, 3 dwg

Description

The invention relates to the oil and gas industry and is intended for insulation and other works during the overhaul of wells.

The closest to the method of conducting insulating work in the well, adopted as a prototype, is the method of isolating the complication zone in the well (patent RU 2257462 C1 of 10.21.2004). The essence of the invention: lower the filling pipes equipped in the lower part with a device for isolating the annular space of the well between the casing and the filling pipes and the annular milling cutter. Hydrocarbon-based cement slurry is pumped through the filling pipes under pressure. Then the cement mortar is forced into the complication zone. Selling cement mortar is carried out with a stepwise increase in pressure to a value exceeding the reservoir pressure and subsequent stepwise depressurization. The operations of increasing the pressure and its subsequent discharge are repeated, but with a different rate of increasing and depressurizing in each of the operations. The resulting cement bridge in the wellbore and the packer are drilled using the filler pipes and an annular milling cutter placed in the well.

The disadvantage of this method is that it is not possible to carry out pressure treatment of the overlying interval with cement or other material, for example acid, or to pressure test the production casing for tightness without delaying the hardening of previously pumped material. If it is necessary to carry out the above technological operations, a time of 48-72 hours is required at the OZZ (waiting for cement to harden).

The objective of the invention is the expansion of technological capabilities when conducting insulating work on the well. At one descent, it is possible to carry out technological operations in the above- and under-packer intervals of the well, without waiting for the hardening of the grouting or other material due to the use of an additional poppet type shut-off valve installed above the drillable packer.

Known drillable packer (PR) for conducting insulating work, adopted for the analogue, comprising a housing, sealing cuffs, an anchor assembly, a shut-off valve and a locking mechanism made in the form of a hollow rod with a piston and a seat for the shut-off valve. The housing is made with a seat for interaction with a removable valve mounted on the bottom of the stem with shear screws (patent RU 2128278 C1 of 03/27/1999).

An analogue of the invention is also a packer drilled for tight separation of the barrel of the production casing of LLC Yugson-Service (patent RU 2296853 C2 from 02.14.2005). The packer contains a barrel with a threaded thread on the outer surface, a sealing element mounted on the barrel, an upper and lower cone, upper and lower grippers that are connected with the cones, a split nut installed in the upper cone, which has a threaded thread on the inner surface, and having a threaded cutting the barrel on the inner surface and threaded cutting the cone on the outer surface. The packer is additionally equipped with a stop located in the lower part of the barrel and representing a cork or cork with a body.

The closest adopted for the prototype is packer equipment (patent RU 2344270 C2 dated 10.26.2006), including a drillable packer with sealing elements mounted on the tubular barrel, oppositely directed slip units, a latch and a non-return valve, and a landing tool with a cylinder resting on the upper packer slips, and a tubular rod with pistons attached to the packer check valve. Between the cylinder and the tubular rod of the landing tool, an additional piston is placed with axial freedom of movement along them, resting on the cone of the upper slip unit, and the latch is located in this cone. Also, the packer check valve is fixed in the open position by a shear element, an additional valve is installed below the check valve, the shut-off element of which is located above the seat and is made in the form of a ball made of an elastic material, such as polyurethane.

Analogs and prototype have common drawbacks and, therefore, the limited use in wells due to the lack of the ability to check for tightness of the above-packer interval of the well, they do not allow two intervals to be processed above and below the packer at different pressures with one or another kind of material and technological operations in overpacker interval without waiting for the hardening of cement or other material pumped into the subpacker interval.

As well as a disadvantage of the known drillable packers is poor drillability due to the rotation of parts during their destruction by a rotating destructive tool.

The aim of this invention is to provide the possibility of pumping cement or other material in two intervals located in the sub- and over-packer space at different pressures, improving drillability of the packer, as well as increasing the reliability of the connection-disconnection of the landing tool with the drillable packer (PR).

The problem is solved in that:

- the drillable packer (PR) has two dividers, the upper one is in the form of a poppet valve, which includes a body attached to the barrel, and a spring-loaded plate located in the hydraulic cylinder cavity, and the lower separator is made in the form of a plug installed on the end of the hydraulic installation tool rod, overlapping flow section of the packer;

- the mechanism for fixing the packer contains dogs made in the form of a sleeve cut into sectors, on the inner surface of which there are teeth for interacting with a threaded thread on the outer surface of the barrel of the PR, moreover, an elastic clip, for example, rubber, is crimped along the outside of the dog;

- between the upper cone and the sealing element PR mounted support sleeve with bilateral sawtooth protrusions and depressions, for example, slots included in the mating grooves of the upper cone and the sealing element, the lower end of which also has sawtooth protrusions included in the mating grooves of the lower cone, which eliminates the rotation of the elements packer when drilling;

- in the lower part of the stem of the installation hydraulic tool (IHG) there is a sleeve with a landing seat for a throw ball fixed with shear elements, and in the place of installation of the sleeve the rod has radial holes with balls located in them, forming a lock between the IHG and PR;

- all PR elements are made of easily drilled materials, with the exception of the throw ball, shear sleeve and lock balls made of steel;

- steel elements are held and removed from the well in a basket located to the lower part of the IHG rod.

The proposed method of conducting insulation work in the well and packer equipment solves the problems of increasing the efficiency of the technology of repair and insulation work by eliminating repeated tripping and hoisting operations (SPO) and, if necessary, conducting operations after cementing, without waiting for the cement to harden (OZZ), which leads to to reduce the time of the complex repair work, improve the quality of insulation work, reduce time and material costs for drilling packer equipment.

To obtain such a technical result, a method for conducting insulating work in a well is proposed, which consists in lowering a pipe string with PR on a landing tool. During the descent, the pipes are self-filling with the borehole fluid through the radial channels in the basket of the installation hydraulic tool (IUG). After the PR reaches the specified depth, a ball is thrown into the pipe string. Landing and sealing of PR are made. Then the required volume of material is pumped into the under-packer space. At the end of the work, the pipe string is raised with the IUG. When lifting the IUG, the plug installed on the end of the IUG rod closes the PR passage channel from below. After the rod is completely removed from the PR, the poppet valve installed in the upper part of the PR is closed, providing the possibility of carrying out technological operations in the overpacker zone. Then, if necessary, the material is processed under pressure of the overlying interval or pressure testing of the production casing is carried out for tightness without delaying time at the OZZ, and this does not depend on the direction and magnitude of the pressure drop in the over- and sub-packer zones.

The invention is illustrated by drawings.

Figure 1 shows the device packer equipment in the initial transport position.

Figure 2 presents the packer equipment in the working position (sealed) during the injection of material under pressure into the lower interval.

Figure 3 shows the packer equipment in the process of pumping material into the upper interval without affecting the lower interval.

Packer equipment for insulation work in the well consists of a drillable packer (PR) and a hydraulic installation tool (IUG).

The drillable packer (Fig. 1) consists of a barrel 1 with notches 2 on its outer surface, a sealing element 3, lower and upper explosive dies 4, 5 and cones 6, 7. In the lower part of the barrel, a support 8 is supported, on which the lower explosive dies 4, in the grooves of which opposite teeth 9 are inserted. The lower and upper dies from spontaneous operation are fixed with shear elements 10, 11 to the lower and upper cone, respectively. The upper end of the lower cone 6 is made with sawtooth protrusions and depressions 12, for example, splines interacting with the mating grooves of the sealing element 3. Between the sealing element 3 and the upper cone 7 there is a support sleeve 13 with bilateral sawtooth protrusions and depressions. The lower end of the sleeve 13 is engaged with the sealing element 3, and the upper end - with the grooves on the upper cone 7. The locking mechanism of the packing is a gear mechanism of intermittent movement, allowing the elements of the packer, namely the lower cone 6, the sealing element 3, the sleeve 13, the upper cone 7 to move relative to the trunk of the packer 1 in one direction and does not allow you to move in the other. The packing fixation mechanism comprises dogs 14, supported by a sleeve 13 and installed inside the upper cone 7. Dogs 14 are made in the form of a sleeve cut into sectors. On the inner surface of the dogs 14 there are teeth that engage with a threaded thread 2 on the barrel of the PR. The notches are in the form of asymmetrical teeth having an emphasis on one side. The movement of the barrel of the packer 1 relative to the IHG stem is limited to the dogs 14, which are pressed against the barrel by an elastic clip 15.

In the upper part of the barrel of the packer 1, a poppet valve 16 is installed. The poppet 16 is spring-loaded to close the valve and close the passage section of the PR.

The installation hydraulic tool consists of a hydraulic cylinder 17 and a rod 18. The rod 18 in the upper part has openings 19 for communicating the tube space with a cavity A formed between the hydraulic cylinder 17 and the rod 18. In the lower part, the rod 18 is made in the form of a basket 20 with radial overflow holes 21 The tube 23 is attached to the end of the basket 20 by means of shear elements 22.

The connection between the PR and the IHG is detachable by means of a lock in the form of balls 24 mounted in radial holes on the stem 18. The holes are made through in the lower part of the stem 18 above the basket 20. Balls 24 abut against the lower end of the barrel 1 and support 8, and from falling out they are held by a shear sleeve with a seating seat 25 for a throw ball 26. The sleeve 25 is fixed in the stem 18 with shear elements 27. All PR elements are made of easily drilled materials, for example duralumin, with the exception of the throw ball 26, shear sleeve 25 and ball lock 24, made of steel. These PR 26-24 elements are not drilled, but are removed from the well in a basket 20 located in the lower part of the IHG rod.

Drillable packer works as follows.

Lower the pipe string with PR in the transport position (figure 1). During the descent, the pipes are self-filling with the borehole fluid through the radial transfer openings 21 in the basket 20. After the PR reaches the specified depth, the ball 26 is thrown into the pipe string. When the pipe pressure is created, the ball 26 closes the seat 25, the liquid flows through the openings 19 into the cavity A formed between the hydraulic cylinder 17 and the rod 18 and moves the hydraulic cylinder 17 down, then through the upper bursting dies 5, the upper cone 7 and the sealing element 3, the movement is transmitted to the lower cone 6. Moreover, the teeth of the dogs 14 under the action of the movement of the cone 7 ne emeschayutsya on threaded stem 2 of the packer 1, once the tooth reaches the end position of notch occurs at a lower perescholkivanie notch. The holder 15, made of elastic, for example rubber, provides a tight pressing of the dogs 14 to the barrel of the packer 1. At a certain design pressure, the lower shear elements 10 are cut and the lower bursting dies are activated 4. The sealing element 3, deforming, overlaps the annular annular space, then the shear occurs the upper shear elements 11 and the operation of the upper bursting dies 5. With a further increase in pressure, the shear elements 27 holding the seat 25 in the stem 18 are destroyed. The seat 25, ball 26 and balls 24 fall a cart 20 at the end of the rod 18, opening the passage for injection of material into the reservoir through the radial openings 21. The downcomers are produced planned production operations in packer space (2). At the end of the work, when lifting the pipe string with the IHC, the plug 23 closes the PR channel from the bottom (Fig. 3). After removing the IHG from the PR, the poppet valve 16 closes, thereby ensuring that the differential pressure on the packer is retained from above. Then, if it is necessary to process the over-packer interval, the YOG is raised on the pipes to a predetermined depth and the material is pumped into the overlying interval (Fig. 3). Also, if necessary, it is possible to compress the production casing for tightness without delaying the hardening of previously pumped material.

At the end of the insulation process, the pipe string is lifted along with the IHG from the well.

The practice of commercial applications shows that the technical and economic effect of the invention consists in providing the possibility of pumping material in two intervals located above and below the packer, regardless of the direction and magnitude of the pressure drop, as well as a significant improvement in drillability of the packer, which leads to a reduction in repair time work, improving quality and reducing the cost of insulation work.

Claims (3)

1. A method of conducting insulating work in a well, including lowering a string of pipes with a packer drilled on a planting tool and installing it in a predetermined interval, pumping cement mortar through pipes into the under-packer space, undocking and raising the planting tool, waiting for the cement to solidify, drilling the packer and the resulting cement a bridge in the wellbore, characterized in that after processing the under-packer space under pressure with a material, the installation hydraulic tool is removed from EPA drillable and processing is performed under pressure or overlying interval pressurization is carried out on the production tubing leaks without time delay on solidification previously injected material, regardless of the direction and magnitude of the differential pressure above and below the packer zones. 2. Packing equipment for insulation work, including a drillable packer, containing a threaded barrel on the outer surface, a sealing element, upper and lower bursting dies, a shut-off valve, a packer locking mechanism, and a hydraulic landing tool with a cylinder, piston, rod, and lock assembly , a non-return valve, characterized in that the packer drilled in the upper and lower parts has two separators, the upper is made in the form of a poppet valve that holds the pressure drop from above when removing the installation hydraulic tool from the drillable packer, including a housing attached to the barrel and a spring-loaded plate placed in the hydraulic cylinder cavity, and the lower one in the form of a plug installed on the rod end of the installation hydraulic tool, overlapping the passage section of the drillable packer and holding the pressure drop from below; the packer fixing mechanism contains dogs made in the form of a sleeve cut into sectors, on the inner surface of which there are teeth for engaging with thread cutting of the outer surface of the drillable packer barrel, and an elastic clip is crimped along the outer forming dog, a support is installed between the upper cone and the sealing element of the drillable packer a sleeve with bilateral sawtooth protrusions and depressions, for example, slots, included in the mating grooves of the upper cone and the sealing element The tent, the lower end of which also has sawtooth protrusions included in the mating grooves of the lower cone, also has a sleeve with a seating seat under the throw ball fixed in the lower part of the installation hydraulic tool rod, fixed with shear elements, and the rod has radial holes with the balls located in them, forming a lock between the hydraulic installation tool and the drillable packer. 3. Packer equipment according to claim 2, characterized in that all the elements of the drillable packer are made of easily drillable materials, with the exception of the throw ball, shear sleeve and lock balls made of steel, and the steel elements are held and removed from the well in a basket located in bottom of the stem of the hydraulic installation tool.

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