RU2654088C1 - Antiflying anchor - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: invention relates to oil industry and can be used for oil extraction by electric centrifugal pumps. Antiflying anchor contains a tube for the passage of liquid with a support sleeve rigidly mounted in the upper part, a shock-absorbing unit in the form of a compression spring with a cone-shaped piston arranged on the pipe and an anchoring mechanism having sliding dies. Cone-shaped piston is fixed on the pipe with the help of a soluble element. As a soluble element, a radial pin passing through the pipe or a ring located under the base of the piston can be used.

EFFECT: technical result is a simplification of putting the anchor into functional condition operation and high reliability of the device activation.

5 cl, 6 dwg

Description

The invention relates to the oil industry and can be used for oil production by electric centrifugal pumps.

The known design of the anti-flight anchor [patent RU No. 2490420 C1, IPC ЕВВ 23/00, publ. 08/20/2013, BI No. 23], containing the upper and lower sub, a pipe for the passage of fluid, a piston with a cone located on the pipe and anchor dies, and a shaped groove is made on the pipe below the cone, into which a guide pin is inserted.

The disadvantage of this device is the difficulty of landing the device in a given interval of the casing of the well, which requires tripping and other operations.

The known design of the anti-flight device (YAKRO-PPE-1, NFP Packer), installed in the lower part of the ESP. The device comprises a central pipe and an anchoring mechanism. A feature of the device is that it only works when the unit breaks.

The disadvantage of this device is its low reliability, since the anchor mechanism only works when the unit falls down during a break, respectively, there is no resting friction between the dies and the casing walls.

The closest in technical essence to the proposed one is a non-flying anchor containing a pipe for the passage of fluid with a support sleeve rigidly mounted in the upper part, a shock-absorbing unit in the form of a compression spring with a cone-shaped piston placed on the pipe, and an anchor mechanism. The locking mechanism is made in the form of movable spring-loaded sliding dies with a guide pin moving along a curly groove made on a pipe [patent RU No. 2455454 C1, IPC ЕВВ 23/00, publ. July 10, 2012, BI No. 19].

The disadvantage of the prototype is the complex installation procedure, which includes the descent, the search for a groove in the casing sleeve and the translation of the anchor from the transport position to the working position, as well as the operation of the anchor only at the time of breakage.

The objective of the present invention is to simplify bringing the armature into working condition and to increase the protection of the installation by bringing the armature into working position before it breaks.

The specified technical result is achieved by the fact that in the non-flying anchor, containing a pipe for fluid passage with a support sleeve rigidly mounted in the upper part, a shock absorbing unit in the form of a compression spring with a cone-shaped piston and an anchoring mechanism having sliding dies according to the invention is placed with the possibility of interaction , the cone-shaped piston is fixed to the pipe using a soluble element.

At the same time, at least one radial pin passing through the pipe is used as a soluble element. In some embodiments, the soluble element may be in the form of a ring placed under the base of the piston.

To reduce the contact area between the piston and the dies, knurling or grooves can be formed on the piston surface.

Due to the possibility of dissolution of the element fixing the piston and holding the spring interacting with it, the anchor will be brought into working position a short time after the descent of the installation, that is, until the moment of breakage. Moreover, when the installation is broken, the friction between the dies of the anchor and the walls of the casing will be higher due to static friction.

The essence of the claimed invention is illustrated by drawings, where in FIG. 1 is a diagram of an anti-flight anchor with a soluble pin; in FIG. 2 is a diagram of an anti-flight anchor with a soluble ring; in FIG. 3 - anti-flight anchor with open dies; in FIG. 4-6 show variations in the surface shape of the piston.

The anti-flight anchor (Fig. 1) contains a central pipe 1, on which a supporting sleeve 2 with an annular collar is mounted, a spring 3 and a cone-shaped piston 5 docked with the sleeve 2. The spring 3 is located around the sleeve 2 and the upper part of the piston 5, while its upper the end rests on the collar of the sleeve 2, and the lower - on the protrusion of the piston 5. On the lower part of the piston 5 are expandable dies 6, which are mounted on the sleeve 7, mounted on the pipe 1, and partially covered by a casing 9. The casing 9 is secured with shear screws 8 on the sleeve 7. On the lower end of the pipe 1 on return the perforated tip 10.

The anchor is equipped with a soluble element that fixes the piston 5 on the pipe 1. As a fixing soluble element, a radial pin 4 inside the conical piston 5 passing through the pipe 1 can be used.

As an alternative (FIG. 2), a soluble ring 11 may be used located in the gap between the piston 5 and the sleeve 7.

In the pipe 1 can be made additional holes 12 for better contact with the reservoir fluid of the dissolved ring 11.

To reduce the risk of jamming of the piston 5 between the expandable rams 6 with a large axial force, they try to reduce the contact area between the piston 5 and the rams 6. To this end, the conical surface of the piston 5 in contact with the rams 6 can be made with grooves (Fig. 4, 5 ), or it can be applied knurling (Fig. 6), which increases the surface roughness to reduce the contact area.

The soluble ring 11 may have holes and grooves for better contact with the formation fluid and for faster dissolution.

The soluble pins or ring may be made of sodium chloride or any other material soluble in the formation fluid.

The ram and piston materials can be anti-friction to reduce the friction of the rams against the piston.

The device operates as follows.

The anti-flight anchor is installed on the base of the electric motor or the measuring motor block through a threaded connection at the upper end of the pipe 1. The dies 6 are in the transport position and do not create obstacles for descent. The spring 3 is preloaded by fixing the piston 5 on the pipe 1 with the help of a radial pin 4 (or a preloaded ring 11). After the equipment is lowered into the well, the chemical process of interaction of the material of the soluble pin 4 (or the soluble ring 11) with the formation fluid begins. Within 1 to 15 days, depending on the selected material, the locking element (pin 4 or ring 11) dissolves, the piston 5 begins to move downward under the action of the spring 3 and expands the dies 6 (Fig. 3). Unclenched dies 6 abut against the wall of the casing. In the event that the weight of the equipment is unloaded to the anchor (when the tubing is cut off, the gas separators are cut, etc.), the force on the supporting dies increases, as a result of which they “crash” into the casing wall with great effort and prevent the submersible equipment from falling onto the bottom of the well.

To remove the anchor from the well, it is necessary to give upward tension with a force that ensures cutting of the screws 8, as a result of which the pipe 1 with the piston 5, the sleeve 2 and the spring 3 rise up, which leads to a decrease in pressure on the dies 6. With a further rise, the tip 10 abuts the end face of the sleeve 7, the dies 6 are released from friction against the walls of the column and pressed against the piston 5. The equipment is freely removed from the well.

The proposed design of the armature provides high reliability of operation, since after dissolving the pin or ring, the armature is activated and the dies abut against the walls of the casing. When unloading the weight of the anchor, the force of breaking the dies only increases.

Claims (5)

1. An anti-flight anchor, comprising a pipe for the passage of fluid with a support sleeve rigidly mounted in the upper part, a shock absorbing unit located on the pipe in the form of a compression spring with a cone-shaped piston, and an anchor mechanism having sliding dies, characterized in that the piston is fixed to the pipe using a soluble item. 2. The anti-flight anchor according to claim 1, characterized in that at least one radial pin passing through the pipe is used as a soluble element. 3. The anti-flight anchor according to claim 1, characterized in that the soluble element is made in the form of a ring placed under the base of the piston. 4. The anti-flight anchor according to claim 1, characterized in that the piston surface is made with grooves. 5. The anti-flight anchor according to claim 1, characterized in that the knurling is made on the surface of the piston.

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