RU2459928C1 - Packer - Google Patents

Abstract

FIELD: oil and gas production.

SUBSTANCE: packer includes hollow shaft, sealing elements with stops mounted on the shaft, anchor unit that consists of casing with cone with slots and plates installed in them, connected to hydraulic cylinder piston via rods, the cavity of the cylinder is connected to the cavity of the shaft through radial channel and extension-type connection pipe mounted at the lower end of hollow plunger. Note that the piston is spring-loaded downwards in relation to the cylinder - to transport position and the rods are assembled consisting of upper, pin-connected to the plates, and lower, spherically-connected to the piston, parts that are interconnected via threaded connection adjusting the rod length. Sealing elements on outer surface contacting the stops can be equipped with facets, the quantity of sealing elements can exceed two and additional intermediate stops can be arranged between them, under the sealing elements there can be installed a driving washer rigidly connected to the corresponding intermediate support.

EFFECT: extension of packer functional capabilities for operation in slope-directed and horizontal areas of the wells, increase of packer reliability, simplification of packer assembly.

5 cl, 2 dwg

Description

The invention relates to the oil and gas industry and is intended for the separation of the annulus, isolation of formations and research wells during drilling.

The well-known "Packer" (patent SU No. 1514905, IPC E21B 33/12, published in Bull. No. 38 dated 10/15/89), containing a hollow barrel with a sub and a radial channel, a sealing element with stops placed on the barrel, placed under an anchor assembly including a housing with a cone with grooves and dies installed in them, connected by rods with a cage, a hydraulic actuator assembly including a hydraulic cylinder rigidly connected to the housing of the anchor assembly with a cavity hydraulically connected in the initial position with the barrel cavity through its radial channel and placed in it a spring a casing fixed at the bottom of the packer on the hydraulic cylinder, a casing in the lower end of the barrel installed under the radial channel and a fitting tip located in the casing with a side channel with a surface inclined to the axis of the packer and a choke hole, the passage channel of the barrel being made equally sized with the inner channel of the drill pipe string, the housing of the anchor assembly is made with windows for rams, internal grooves for traction and an internal groove with emphasis under the clip and is located in the upper part of the hydro Lindgren, the inclined surface side channel of the choke tip is formed by two intersecting surfaces.

The disadvantages of this device are:

- the possibility of clogging the nozzle tip when working with large and coarse fiber fillers of grouting mixtures, since the nozzle hole is an obstacle to the movement of the mixture;

- you need a high flow rate of liquid for packing, since the nozzle hole, designed for pumping grouting mixture with filler, does not provide the necessary pressure drop to extend the dies in the working position;

- the impossibility of regulating the position of the dies during assembly, since the fastening of the cylinder sleeve to the dies is carried out by means of rigid rods, which requires high precision manufacturing of mating parts;

- high loads when removing the packer, since the radial force from pressing the sealing elements to the walls of the well is transmitted to the packer barrel, which creates a friction force that prevents the barrel from moving upward when removing the packer, and can lead to emergency situations associated with breakage of the pipe string and the destruction of the sealing elements.

The closest in technical essence and the achieved result is “Packer” (patent RU No. 2162930, IPC E21B 33/12, published in Bul. No. 4 of 02.10.2001), containing a hollow barrel, the passage channel of which is made equally sized with the inner the channel of the drill pipe string with an adapter and a radial channel, sealing elements with stops mounted on the barrel, an anchor assembly located under them, including a housing with a cone with grooves and dies connected therewith, with a piston of the hydraulic cylinder, the cavity of which is in communication with the cavity with the barrel through the radial channel and the packer landing control unit mounted on its lower end, the packer landing control unit made in the form of a sliding choke device located coaxially with the hollow barrel of the packer and closed by a casing, while the stops of the sealing elements are made profile.

The disadvantages of this device are:

- the ability to open the packer when it is lowered into the well, especially in inclined and horizontal sections, since the packer dies are not spring loaded in the transport position and rise from the reaction of the well walls, jamming the packer;

- the impossibility of regulating the position of the dies during assembly, since the piston of the hydraulic cylinder is fixed to the dies by means of rigid rods, which requires high precision manufacturing of mating parts;

- high loads when removing the packer, since the radial force from pressing the sealing elements to the walls of the well is transmitted to the packer barrel, which creates a friction force that prevents the barrel from moving upward when removing the packer, and can lead to emergency situations associated with breakage of the pipe string and the destruction of the sealing elements.

The technical objectives of the proposed invention are to expand the functionality of the packer to work in directional and horizontal sections of the wells and increase its reliability due to the reliable fixation of the dies in the transport position and to prevent jamming of the packer when it is removed, as well as simplifying the assembly of the packer due to the possibility of regulating the position of the dies.

The technical problem is solved by a packer containing a hollow barrel, sealing elements installed on the barrel with stops and an intermediate stop, an anchor unit placed under them, including a housing with a cone with grooves and dies installed in them, connected by rods to the hydraulic cylinder piston, the cavity of which is connected with the barrel cavity through a radial channel and a sliding fitting mounted on the lower end of the hollow rod.

What is new is that the piston is spring-loaded downward relative to the hydraulic cylinder to the transport position, and the rods are made of prefabricated ones consisting of an upper part, articulated with dies, and a lower part, connected by a spherical connection to the piston, which are interconnected by a threaded connection regulating the length of the rod.

Also new is the fact that the sealing elements on the outer surface adjacent to the stops are provided with chamfers.

Also new is the fact that the number of sealing elements is more than two, and additional intermediate stops are placed between the sealing elements.

Also new is the fact that under the sealing elements a movable sleeve is mounted rigidly connected to the corresponding intermediate stop.

Figure 1 shows the packer (partially in section) in the transport position, figure 2 - node a in figure 1.

The packer (Fig. 1) contains a barrel 1 with a cavity 2 in the form of a through radial channel, elastic sealing elements 3 (for example, rubber) installed on the barrel 1 with extreme 4 and intermediate 5 stops, under which an anchor assembly 6 is placed, including a housing 7 with a cone 8 with grooves 9 and dies 10 installed therein. The dies 10 are connected by rods 11 to the piston 12 of the hydraulic cylinder 13, the cavity 14 of which is in communication with the cavity 2 of the barrel 1 through the radial channel 15. At the lower end of the barrel 1, a sliding fitting 16 is installed.

In this case, the piston 12 with the aim of fixing it in the transport position is spring-loaded downward by a spring 17 relative to the hydraulic cylinder 13, and the thrust 11 is made of teams consisting of the upper 18 (Fig. 2) and the lower 19 parts. Moreover, the upper part 18 of the rod 11 is a cylindrical hinge located in the ram 10, inside of which a through cylindrical thread 20 is made across the axis 20. The lower parts 19 of the rods 11 have a mating external thread 21 on top for connecting to the upper parts 18 of the rods 11, and the bottom is spherical connection 22 for connection with the piston 12.

The sealing elements 3 (Fig. 1) on the outer surface adjacent to the stops 4, 5 are provided with chamfers 23, which prevents jamming of the packer during transportation inside the well (not shown in Fig.) And prevents leakage of the sealing elements 3 down and up from the place their installation in the well, thereby facilitating the withdrawal of the packer from the worker to the transport position. For more reliable sealing in the well, the number of sealing elements 3 may be more than two, and additional intermediate stops 5 are placed between them. Under the sealing elements 3, in order to reduce radial loads on the barrel 1 of the packer, movable bushings 24 are fixed relative to the barrel 1 and are rigidly connected to corresponding intermediate stops 5.

The packer works as follows.

Before lowering into the well on the basis of production services, the length of the packer rods 11 (FIG. 2) is adjusted using the threaded connection 20, 21, screwing or unscrewing (thanks to the spherical connection 22) the lower parts 19 of the rods 11 relative to their upper parts 18 and thereby achieving uniform exit dies 10 in the working position.

Next, on the drill pipe string (not shown in FIG.), The packer is lowered into the well to a predetermined depth. Drilling fluid is pumped into the pipe string. Due to the pressure drop arising in the cavity 2 (Fig. 1) of the barrel 1 in front of the choke hole 25 of the expandable fitting 16 and transmitted through the radial channel 15 into the cavity 14 of the hydraulic cylinder 13, the piston 12 moves upward overcoming the resistance of the spring 17. Through the rod 11, the piston 12 acts on the dies 10, leading them along the grooves 9 upward along the cone 8 of the housing 7 until it stops against the walls of the well, thereby fixing the packer in the well.

Then the axial load is created on the packer using drill pipes. The trunk 1 of the packer moves downward, acting through the stops 4, 5 on the sealing elements 3, which, deforming in the radial direction, are adjacent to the walls of the well and disconnect the annulus.

In this case, the internal cavity 14 of the hydraulic cylinder 13 is blocked by the barrel 1 of the packer, and the petals 25 of the sliding fitting 16 are released from the housing 7 and diverge to the sides. The feedthrough channel 2 of the packer is free for technological operations, including the injection of grouting mixtures with coarse and coarse fiber fillers.

To remove the packer from the well, the mud pumps are turned off and the drill string is pulled. The trunk 1 of the packer, rising up, removes the load from the sealing elements 3, which come to their original position. At the same time, thanks to the movable bushings 24 of the intermediate stops 5 located between the barrel 1 and the sealing elements 3 of the packer, radial loads on the barrel 1 from the sealing elements 3 are eliminated, allowing it to freely move up.

In this case, the dies 10 due to the return spring 17 acting on them through the piston 12 and the rod 11 and, partially from friction against the well walls, also occupy the transport position, and the petals 25 of the sliding fitting 16 enter the housing 7.

The technical advantages of the proposed packer are the expansion of its functional capabilities for working in directional and horizontal sections of wells and increased reliability compared to the prototype due to the reliable, thanks to the return spring, fixing the dies in the transport position and eliminating jamming of the packer when removing it due to moving bushings separating the packer barrel from the sealing elements, as well as the presence of chamfers on the outer surface of the sealing elements. In addition, due to the threaded connection connecting the upper and lower parts of the dies rods, it is possible to control the length of the rods and dies, respectively, in the transport and operating positions, which greatly simplifies the assembly of the packer.

Claims (5)

1. A packer containing a hollow barrel, sealing elements installed on the barrel with stops and an intermediate stop, an anchor assembly located under it, including a housing with a cone with grooves and dies installed in them, connected by rods to the hydraulic cylinder piston, the cavity of which is connected to the barrel cavity through radial channel and a sliding fitting mounted on the lower end of the hollow barrel, characterized in that the piston is spring loaded downward relative to the hydraulic cylinder to the transport position, and the rods are prefabricated, consisting of the conductive top is pivotally connected with rams and bottom connected by means of the spherical joint to the piston portions, which are interconnected by means of a threaded connection, the regulating rod length. 2. The packer according to claim 1, characterized in that the sealing elements on the outer surface adjacent to the stops are provided with chamfers. 3. The packer according to claim 1 or 2, characterized in that the number of sealing elements is more than two, between which additional intermediate stops are placed. 4. The packer according to claim 1 or 2, characterized in that under the sealing elements a movable sleeve is mounted rigidly connected to the intermediate stop. 5. The packer according to claim 3, characterized in that under the sealing elements there is a movable sleeve rigidly connected to the corresponding intermediate stop.

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