RU124921U1 - DEVICE FOR CREATING PERFORATION CHANNELS IN A WELL - Google Patents

Abstract

A device for creating perforation channels in a well, comprising a housing formed by a wedge and at least two hydraulic cylinders placed one after another with connected piston rods fixed to a support and having an axial channel communicated by means of tubes with hydraulic monitor channels of at least two working bodies installed in the grooves of the support and the wedge with the possibility of radial reciprocating movement, characterized in that the circulation channels are made in the hydraulic cylinders, one of the piston rods uet cylinder with a sealed chamber, while in others the plunger downcomers formed communicating with the axial channel.

Description

The utility model relates to the oil and gas industry, and in particular to the field of secondary opening of the formation by creating perforation channels in the well.

A device for creating perforation channels in the casing of a well according to the patent for utility model RU 68587 is known. The device comprises a tubular body with a hydraulic cylinder with a shank and a spring-loaded piston placed thereon, made with the possibility of limited axial movement relative to the tubular body. The piston is spring-loaded upward relative to the hydraulic cylinder and the tube body, and from below it is equipped with a wedge pusher interacting with tool holders with perforating cutters, which are placed at the end of the shank with the possibility of radial reciprocal-longitudinal movement under the action of the wedge pusher. The tool holder and cutter have hydraulic monitor channels in communication with the overflow channels of the wedge pusher. One or more additional hydraulic cylinders with additional pistons that are connected to the piston and are mounted so that between the pipe body and additional pistons there is an annular cavity in communication with the over-piston cavity of all cylinders above the hydraulic cylinder. The tube body is separated by a blank partition, the upper cavity of which is in communication with the annular cavity, and the lower cavity is provided by transfer holes with a piston cavity of the hydraulic cylinder. The lower cavity of the tube body is also configured to interact with the annular cavity when the spring-loaded piston is moved down.

The disadvantages of the device are the low hydromonitor effect created by the formation of channels in the bottomhole formation zone, due to design features that do not allow for tightness of the connection of the overflow channels of the wedge and the tool holder, which leads to significant losses in the volume of working fluid and its pressure entering the hydraulic monitors. It should be noted that even with a slight change in the inner diameter of the casing, the alignment of the wedge channels and the tool holder "is lost", which also negatively affects the tightness of the hydraulic system and, accordingly, the hydraulic monitoring effect. All of the above has an extremely negative effect on the energy of the jet, which will not be enough to erode the caverns and, as a result, on the efficiency of the formation treatment. In addition, the device has a rather complicated design.

Among analogues, devices for creating perforation channels in the casing of a well according to the patents for utility model RU 115002 and RU 115407 are most effective.

For the majority of similar essential features and the achieved result, the prototype according to patent RU 115407, IPC ЕВВ 43/114, op. 12/01/2011

The prototype device has a housing formed by a wedge and the walls of at least two hydraulic cylinders placed one after another with rod pistons connected to each other and mounted on a support, one of which is spring-loaded. At least two cutters with hydraulic monitors and tool holders are placed in the grooves of the support and the wedge with the possibility of radial reciprocating movement. Piston rods have an axial channel communicated by transfer channels with sub-piston cavities of hydraulic cylinders, and tubes and channels of tool holders with hydraulic monitors of cutters.

The disadvantage of the design of the prototype is the unreliability of the mechanism for returning to the original transport position of the working bodies of the device, for example, cutters with tool holders. The spring operates with maximum force only at the moment of its full compression, when the tubing string is used to exit the working bodies from the casing after perforation, and at the time when it is necessary to bring the working bodies to their original transport position so that they do not scrape along the inner wall of the casing when moving the device deep into the well (which can lead to the extension of the working bodies), the spring is ineffective, because it is almost unclenched and its effort to overcome the frictional forces between the rod pistons and hydraulic cylinders is minimal. Also, with multiple cycles of perforation, there is a possibility of spring breakage, which can lead to jamming of the entire device and an emergency at the well.

The task to which the utility model is directed is to increase the reliability and efficiency of the device.

The technical result is achieved in that in a device for creating perforation channels in a well, comprising a body formed by a wedge and at least two hydraulic cylinders arranged one after another with connected piston rods fixed to a support and having an axial channel communicated by means of tubes with hydraulic monitors the channels of at least two working bodies installed in the grooves of the support and the wedge with the possibility of radial reciprocating movement, according to the utility model, in hydraulic cylinders are made circulation channels, one of the stem-porous forms a sealed chamber with the hydraulic cylinder, and in the other piston rods there are transfer channels communicating with the axial channel.

The execution of the housing at the same time with the wedge and hydraulic cylinders provides the rigidity and reliability of the structure, necessary in cases of its possible "anchoring" when removing the working bodies from the well. The presence in one hydraulic cylinder of a sealed chamber in which air under atmospheric pressure is located, transfer channels in the piston rods of other hydraulic cylinders for communication with the axial channel and circulation channels in the hydraulic cylinders for communication with the annulus, in combination with other features of the device, increase its efficiency with a guaranteed return of the working bodies to their original transport position due to the differential pressure in the system.

The inventive utility model is illustrated by the example of a device with two hydraulic cylinders, two working bodies and accompanying drawings, which depict:

Figure 1 - General view of the device with a partial section;

Figure 2 is a side view in partial section.

The device comprises a housing 1 formed by the walls of hydraulic cylinders 2, 3 and a wedge 4 having grooves 5, in which two diametrically located working bodies 6 are located, installed in radial grooves 7 of the support 8. In each working body 6, there are hydraulic monitor channels 9, and in hydraulic cylinders 2 and 3 - circulating channels 10 for communication annular and nadpiston spaces. The piston rods 11 and 12 of the respective hydraulic cylinders 2 and 3 are interconnected and have a common axial channel 13, which communicates with the sub-piston cavity 14 of the hydraulic cylinder 2 through the transfer channel 15 and with the hydraulic monitor channels 9 of the working bodies 6 through a pair of hollow rods 16 of the rod pistons and tubes 17. The piston rod 12 forms with the hydraulic cylinder 3 in the housing 1 an airtight chamber 18 with air under atmospheric pressure and is connected to the support 8 by two hollow rods 16. To seal the device, all connections of the structure are equipped with seals.

The operation of the device is as follows.

The device is mounted on a tubing string (tubing) and lowered into the well to the perforation interval. Then, the working fluid is supplied through the tubing under pressure, which, passing through the channels 13 and 15 into the sub-piston cavity 14, acts on the piston rod 11 and the piston rod 12 connected to it, moves them up, dragging the support 8 with the workers through the rods 16 bodies 6. In this case, a vacuum is created in the sealed chamber 18, and the working bodies 6 are moved along the grooves 5 of the wedge 4 and the radial grooves 7 of the support 8 until the walls of the casing string 19 touch. The piston rods 11 and 12 are fixed relative to the casing string 19, and the housing 1 , "Stretching" the tubing string, moves down, times firing wedge 4 working bodies 6, the cutting parts of which perforate the walls of the casing 19. At the same time, the working fluid passing through the rods 16, tubes 17 and the hydraulic channels 9 of the working bodies 6, under high pressure goes into the bottomhole formation zone (PZP) and erodes jets of cement stone and adjacent rock, forming caverns, channels.

After the formation of channels in the PZP, the pressure of the working fluid is reduced to atmospheric. The NTK column and the case 1 connected to it are lifted up with the wedge 4, the cutting parts of the working bodies 6 are pulled out from the walls of the casing 19 due to their T-shaped connection with grooves 5 of the wedge 4 and radial grooves 7 of the support 8. Due to the fact that to the sealed chamber 18, the air is at atmospheric pressure, the piston rod 12 tends to its original position, which is also facilitated by the hydrostatic pressure of the column of well fluid falling into the over-piston space of the hydraulic cylinder 3 through the circulation channel 10. Together with the rod the pistons 11 and 12 through the rod 16 moves the support 8 with the working bodies 6, returning them to their original transport position.

Then the device is moved to the estimated distance, the pressure of the working fluid is raised again, and the casing is perforated and channels are formed in the bottomhole formation zone. The cycle is repeated as many times as necessary without removing the device from the well. After the formation of all channels in the well, the flow of working fluid is stopped, the pressure is released to atmospheric pressure, the support with the working bodies returns to its original transport position, and the device is removed from the well.

If necessary, in the design of the proposed device, the number of hydraulic cylinders installed one after another and / or working bodies placed on a support can be increased. The total area of the pistons depends on the number of hydraulic cylinders to create the necessary effort to penetrate the working bodies, the number of which is determined by the required number of perforation channels in the well to open the formation in one cycle.

For perforation of casing strings of small diameter, the device can be made with several successively installed wedges having one working surface.

To increase the efficiency of the device, the hydraulic monitor channels of the working bodies can be equipped with nozzles made of abrasion-resistant material.

The use of a simple, reliable and easy-to-use device design will reduce processing time, significantly increase the efficiency of the secondary opening of formations and reduce material costs.

Claims (1)

A device for creating perforation channels in a well, comprising a housing formed by a wedge and at least two hydraulic cylinders placed one after another with connected piston rods fixed to a support and having an axial channel communicated by means of tubes with hydraulic monitor channels of at least two working bodies installed in the grooves of the support and the wedge with the possibility of radial reciprocating movement, characterized in that the circulation channels are made in the hydraulic cylinders, one of the piston rods uet cylinder with a sealed chamber, while in others the plunger downcomers formed communicating with the axial channel.

Images