RU2398093C1 - Hydromechanical packer - Google Patents

Abstract

FIELD: oil and gas production.

SUBSTANCE: invention relates to oil and gas producing industry to isolate axial channel of casing pipes. Provides for easy withdrawal from well, as well as for multiple use without withdrawal. Hydromechanical packer comprises shaft with radial channels having stop on external surface, hydraulic cylinder with piston, split collet fixed to hydraulic cylinder with anchor arranged on lower end of split collet, sealing ring, seat in lower part of shaft. Outside under the anchor, split collet is equipped with cone-shaped surface arranged with the possibility to interact with piston. Sealing ring is placed on shaft above hydraulic cylinder under sub acting as upper stop and above lower stop inserted telescopically and tightly into hydraulic cylinder equipped with inner recess at the bottom and outer one - at the top. Split collet at the bottom is equipped with inner hooks that cover shaft stop at the bottom with the possibility of disconnection as cone-shaped surface of collet interacts with piston, and cylinder on top has an internal narrowing, which is arranged with the possibility of upward longitudinal motion relative to outer recess of lower stop. Sealing ring may be arranged as assembled, including at least one elastic bush arranged between rigid bushes.

EFFECT: packer makes it possible to maintain any permissible pressure differences in well space separated by packer.

2 cl, 2 dwg

Description

The invention relates to the oil and gas industry and is intended to block the axial channel of the casing pipes and study wells during drilling.

The well-known "Heat-resistant packer" (AS No. 1731937, IPC Е21В 33/12, publ. Bull. No. 17 of 05/07/92), containing a hollow barrel, on which is mounted a cylinder with a thin-walled metal shell, while in the cylinder an expandable cone is installed to form a gap between it and the metal shell, in which a split collet in the form of wedge-shaped cams with a figured annular groove is placed, in which a figured ring extends beyond the metal shell, and a seat under the ball valve is installed in the axial channel of the barrel, and on his bottom con ce is a protrusion for interacting with a cone.

The closest in technical essence and the achieved result is "Hydromechanical packer" (patent RU No. 2235850, IPC ЕВВ 33/12, publ. Bull. No. 25 dated 09/10/2004), including a barrel connected through an adapter with an elevator column, a hydraulic cylinder with an expanding cone and a metal sealing shell, an anchor, a split collet, characterized in that the metal sealing shell is tapered and provided with a sealing ring on the outside, the barrel is equipped with a spring-loaded step sleeve in an axial channel with a seat under aary valve in the upper part and a non-return valve installed with the possibility of axial movement and hydraulic connection of the axial bore of the barrel with the under-packer cavity in the lowermost position and connected with the barrel by a calibrated shear element, the split collet is rigidly connected to the barrel, the anchor is made in the form of an annular protrusion with teeth along the perimeter and installed below the location of the metal sealing shell.

The disadvantages of these devices are the difficulty in manufacturing, the ability to use only once, since to remove the packer it is necessary to drill it, and, as a result, high material costs.

The closest in technical essence and the achieved result is "Hydromechanical packer" (patent RU No. 52607, IPC ЕВВ 33/12, publ. Bull. No. 10 of 04/10/2006), including a barrel with radial channels connected through an adapter to the column pipes, a hydraulic cylinder with a piston connected to the expanding cone, a split collet with an anchor, a sealing ring, a ball valve with a seat connected to the barrel with a calibrated shear element, characterized in that the sealing ring is attached from the bottom to the split collet, which has an uncut end it is rigidly attached from below to the hydraulic cylinder, and the anchor is made in the form of a notched surface protruding externally above the lower end of the split collet, and from the inside under the anchor on the split collet a conical surface is made, while the hydraulic cylinder is arranged to move down relative to the barrel, which is additionally equipped with the outer surface of the stop, made with the possibility of interaction with the expanding cone, which is rigidly connected to the piston ring insert, made with the possibility of interaction with the seal itelnym ring, wherein the piston is adapted to interact with a conical surface of the split collet.

The disadvantages of this device are:

- high loads during extraction, since when the sealing ring is pressed against the walls of the well, a similar force also acts between the sealing ring and the annular insert, which creates a friction force that prevents the packer from being removed, which can lead to emergency situations when removing the packer due to breakage of the pipe string and destruction of the o-ring;

- uneven pressing of the sealing ring due to the presence of inelastic studs installed inside, which significantly reduces the quality of the well separation by the packer and, as a result, the pressure drop at which the packer qualitatively isolates the well space does not exceed 7 MPa.

The technical task of the invention is the creation of a hydromechanical packer that works at high pressure drops in the well and is easily removed from the well.

The technical problem is solved by a hydromechanical packer, including a barrel with radial channels, connected through an adapter with a pipe string and equipped with a stop at the bottom on the outer surface, a hydraulic cylinder with a piston, a split collet with an uncut end from the bottom to the hydraulic cylinder, an anchor located on the lower end of the surface of the split collet, sealing a ring, a saddle located in the lower part of the barrel, and from the inside under the anchor to a split collet equipped with a conical surface, made with the possibility of interaction wii with a piston, and the hydraulic cylinder is made with the possibility of longitudinal movement relative to the barrel.

What is new is that the o-ring is located on the barrel above the hydraulic cylinder under the sub, which plays the role of the upper stop, and above the lower stop, inserted telescopically and hermetically into the hydraulic cylinder, equipped with an internal selection from the bottom and the outside from above, with a split collet equipped with internal hooks covering the bottom bottom, the emphasis of the barrel with the possibility of detachment during the interaction of the taper surface of the collet with the piston, and the cylinder from above - internal narrowing, made with the possibility of longitudinal movement in the top relative to the outer sampling of the lower stop, while the radial channels are made with the possibility of communication with the internal sampling of the lower stop.

Also new is the fact that the o-ring is prefabricated, comprising at least one elastic sleeve located between the rigid bushings.

Figure 1 shows the design of a hydromechanical packer with an axial section in the transport position.

Figure 2 shows the design of the hydromechanical packer with an axial section in the working position.

A hydromechanical packer, including a barrel 1 (Fig. 1) with radial channels 2, connected through an adapter 3 with a pipe string 4 and equipped with a stop 5 from the bottom on the outer surface, a hydraulic cylinder 6 with a piston 7, a split collet 8 with an uncut end from the bottom to the hydraulic cylinder 6, 8 s an anchor 9, located on the lower end of the surface of the split collet 8, a sealing ring 10, a saddle 11, located in the lower part of the barrel 1, and inside the anchor 9, the split collet 8 is equipped with a conical surface 12 configured to interact with the piston 7, and the hydraulic cylinder 6 is made with the possibility of longitudinal movement relative to the barrel 1. The sealing ring 10 is placed on the barrel above the hydraulic cylinder 6 under the sub 3, which plays the role of the upper stop, and above the lower stop 13, inserted telescopically and hermetically into the hydraulic cylinder 6, equipped with an external selection 14 from below and inner 15 from above. The split collet 8 is equipped with internal hooks 16 from the bottom, which cover the bottom 5 of the barrel 1 with the possibility of detaching when the conical surface 12 of the collet 8 is detached from the piston 7. The cylinder is equipped with an internal narrowing 17 made with the possibility of longitudinal movement upward relative to the outer selection 14 of the lower stop 13. The radial channels 2 are configured to communicate with the inner sample 15 of the lower stop 13. The sealing ring 10 to improve the insulation of the inner space of the casing (not shown in Fig. ) made prefabricated, including at least one elastic sleeve 18 located between the rigid sleeve 19. Unauthorized flow of liquid is prevented by means of seals 20 and 21.

The device operates as follows.

The hydromechanical packer is lowered on the pipe string 4 into the well (not shown in the drawing), if necessary, flushing is carried out through the interior of the pipe string and barrel 1. Upon reaching the installation interval (not shown in the drawing), fluid is pumped from the wellhead (not shown) of the well with a high flow rate in the pipe string 4 and barrel 1, the result is a differential pressure due to the presence of a seat 11, narrowing the internal section of the barrel 1, inside the barrel 1 and outside the hydraulic cylinder 6. As a result, the fluid flows through radial anal 2 in the hydraulic cylinder 6 under the internal sample 15 of the lower stop 13, which is held in a static position by the internal narrowing 17 of the cylinder 6, covering its outer sample 14. In this case, the hydraulic cylinder 6 is held in a static state due to the internal hooks 16, covering the bottom stop 5 of the barrel 1. Under the influence of the differential pressure in the hydraulic cylinder 6, the piston 7 moves downward, interacting with the conical surface 12 (Figure 2) of the split collet 8, expanding it. As a result, the anchor 9 is pressed against the walls of the well, fixing the packer in the installation interval, and the internal hooks 16, expanding together with the split collet 8, are released from the stop 5 of the barrel 1. The installation of the hydromechanical packer is determined by the achievement of the time delay (in practice: 3-10 minutes) at a certain liquid flow rate (in practice, 20-30 l / s), the water flowing from the well is again sent to the buffer tank (not shown in Fig.), from which it is taken for pumping through the pipe string 4.

Then unload the pipe string 4 (Figure 2), which through the adapter 3, rigid 19 and elastic 18 of the sleeve of the sealing ring 10 moves the lower stop 13 to interact with the piston 7, compressing it into a split collet 8, and then compresses the elastic sleeve 18 of the sealing ring 10 with the help of rigid bushings 19 until they are sealed against the walls of the well, providing a pressure drop of up to 13-15 MPa.

For use in the production of formation products (not shown in FIG.) Located below the packer, a ball (not shown) can be dropped, which, interacting with the seat 11 of the barrel 1, forms a valve assembly.

To remove the packer, the pipe string 4 with the barrel 1 is pulled up, as a result, the elastic sleeves under the action of elastic forces return to their original state, equalizing the pressure above and below the packer, and the stop 5 interacts with the piston 7, moving it with the lower stop 13 upward relative to the split collet 8 with a hydraulic cylinder 6 fixed by an anchor 9 relative to the walls of the well. When the piston 7 (Fig. 1) exits the conical surface 12, which does not require large axial forces (not more than 200-400 kg), the anchor 9 is released from the engagement with the walls of the well by the clamping force of the split collet 8. Then the hydromechanical packer is removed to the surface on the pipe string 4.

The design of the proposed hydromechanical packer does not require much effort to extract from the well, allows you to use the packer repeatedly, without removing it from the well, while allowing you to keep almost any allowable pressure drop in the space of the packer separated by the well.

Claims (2)

1. A hydromechanical packer, including a barrel with radial channels, connected through an adapter with a pipe string and equipped with a stop at the bottom on the outer surface, a hydraulic cylinder with a piston, a split collet with an uncut end from the bottom to the hydraulic cylinder, with an anchor located on the lower end of the surface of the split collet, a sealing ring , a saddle located in the lower part of the barrel, and inside the anchor a split collet is equipped with a conical surface configured to interact with the piston, and the hydraulic cylinder longitudinally movable relative to the barrel, characterized in that the sealing ring is located on the barrel above the hydraulic cylinder under the sub, playing the role of the upper stop, and above the lower stop, inserted telescopically and hermetically into the hydraulic cylinder, equipped with an internal selection from the bottom and the outer one from above, split the lower collet is equipped with internal hooks, covering the bottom of the barrel stop with the possibility of detachment when the taper surface of the collet interacts with the piston, and the cylinder has friction constriction adapted to move longitudinally upwardly relative to outer bottom stop sampling, wherein the radial channels are adapted to communicate with the internal track lower stop. 2. The hydromechanical packer according to claim 1, characterized in that the o-ring is prefabricated, comprising at least one elastic sleeve located between the rigid sleeves.

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