SU1530738A1 - Arrangement for fluid-tightness testing of casing in well - Google Patents

Abstract

The invention relates to the drilling of wells. The goal is to increase work efficiency by providing repeated crimping while eliminating water hammering. For this, a branch pipe 16 is rigidly connected with the lower part of the support 10 in the upper part along the inner surface of the nozzle 16 with the axial channel and the radial channels 22 in the upper part. In the lower part of the cavity of the nozzle 16 there is a cup 26. spring-loaded relative to it. The device also has a saddle for a casting ball 21, made in the form of a stepped sleeve 18, located in the upper part of the nozzle 16, spring-loaded relative to it and installed with a lateral surface with a greater degree 17 channels 22 in the working position of the device. Fluid from the drill string through the opening of the cavity of the stage 17 and the channels 22 is poured into the well, which ensures the lifting and unscrewing of the pipes without a siphon. 2 Il.

Description

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A cup 26 relative to it. The device also has a saddle for a cast ball 21, thick in the form of a step surface of a greater degree 17 of channels 22 in the working position of the device. Fluid from the drill string through

Chat sleeve 18, located at the top of the hole cavity cavity 17 and channels

it part of the pipe 16, is spring-loaded relative to it and installed with the possibility of overlapping its side

22 is poured into the well, which provides for lifting and unscrewing pipes without a siphon. 2 Il.

the surface of the larger step 17 of the channels 22 in the operating position of the device. Fluid from the drill string through

22 is poured into the well, which provides for lifting and unscrewing pipes without a siphon. 2 Il.

The invention relates to drilling, in particular to devices for testing the tightness of a well casing.

The purpose of the Bretepi is to increase work efficiency by providing repeated crimping while eliminating water hammering.

FIG. Figure 1 shows a device for testing a casing for leaktightness before descending into a well, a section, in fig. 2 - the same, when tested.

The casing leak testing device includes a substation 1, designed to communicate with the drill string, to which case 2 is attached with an axial channel 3. On the outer surface of case 2, a piston A with a shell 5 overlapping radial channels 6 is installed with limited axial movement. reporting cavity 7 of the sub and the housing cavity with a well. In the sub 1, a hole 8 is made, the common cavity of the sub with the over piston cavity 9. The piston 4 is installed with the possibility of interaction through the support 10 with the sealing element 11 located on the housing 2. Under the sealing element 11, the support 12 is rigidly connected to the housing 11 is reinforced inside by elastically deformable elements, made, for example, in the form of curved plates 13 evenly spaced along an annular section, facing towards the outer surface of the seal bodies 11 and interacting in the middle part with elastically deformable split rings 14, or in the form of a compression spring 15, filled in the form of a tight second order cylinder. With the lower part of the support 12 is rigidly connected the pipe 16, executed in the upper part with

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step 17 of a larger diameter of its inner surface. In the axial canape of the pipe 16 in its upper part there is a saddle in the form of a sleeve 18 with a hole 19 and a seal 20 for a casting ball 21, the diameter of which is smaller than the diameter of the hole 19. In the upper part of the pipe in step 17 radial channels 22 are made to communicate the cavity of the pipe with the annular space. The sleeve 18 is made stepped and spring-loaded relative to the nozzle by a spring 23 located in the bore 24 of the nozzle, the diameter of which is less than the diameter of the step 17 and corresponds to the lower stage of the sleeve 18.

The diameter of the step 17 of the nozzle corresponds to the diameter of the larger step of the sleeve 18, the latter having the lateral surface in the working position of the device (Fig. 2) has the ability to block the radial channels 22 of the nozzle 16. In the lower part of the cavity of the nozzle 16, a cup 26 is installed in the bore 25 under the sleeve 18, interacting The spring 26 has a cavity 28, and the bore 25 communicates with a bore a hole 29 made in the lower end of the nozzle 16.

The device works as follows.

In the position shown in FIG. 1, without the waste ball 21, the device on the drill string is lowered into the well (not shown) at the desired interval. At the same time, the string of drill pipes is filled with fluid from the well through the opening 19 of the channels 22 and 3 and the cavity 7, which eliminates the work effort 1; s and the time associated with topping up the pipes. After descending into the drill string, the ball 21 is dropped and the hour is turned on to inject fluid. When the ball 21 is seated on the seal 20, the channel 3 closes and the fluid pressure above the hub 18 begins to increase, after 5

As a result, the sleeve 18 is displaced downward, compressing the spring 23. The sleeve 18 is moved until it stops at the end of the stage 17, thus blocking the radial channels 22 and with increasing pressure the ball 21 is displaced through the seal 20. In the cavity of the bore 24, the pressure increases, with the force of which the cup 26 is pressed downwardly compressing the spring 27 and the liquid is forced out of the cavity of the bore 25 through the opening 29 into the well. Passing the seal 20, the ball 21 falls under its own weight into the cavity 28 of the cup 26 (Fig. 2). By increasing the pressure in the opening 19 of the sleeve and the bore 24 of the nozzle 16 as compared with the well and the difference in the areas of the ends of the sleeve 18, the latter is pressed down and thus constantly closes the openings 22 for the time of fluid injection, ensuring testing.

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As the pressure in the column-25 increases from the action of the springs 27 and 23, the piston

Not pipes and cavities 9, where the fluid is pumped through the opening 8, the piston 4 gradually moves downward, compressing the sealing element 11, in which the elastically deformable elements 13 or 15, compressing, deflate the amount of deflection in the middle part and thereby press sealing rubber to the casing wall

When the pressure in cavity 9 is equal to the pressure of the packer, the casing string is hermetically disconnected and the shell 5 opens the radial channels 6, as a result of which the fluid is injected from cavity 7 into the test section of the casing. At the same time, the piston 4 with the shell 5 does not return to its original position, since although the pressure in cavity 7 and somewhat decreases due to the communication of the radial channels 6 with the well, due to the throttling effect of the hole 8, the pressure in cavity 9 decreases more slowly. In addition, while the compressed elements 13 and 15 tend to move the support 10, and hence the piston 4 up, this movement is slowed down by the relaxation of the rubber and its rubbing against the walls of the casing. Further injection of fluid into the well to the pressure of the packer, and then the pressure, leads to the fact that the forces on the piston 4 from the top and bottom are balanced and further compression

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sealing element 11 is due to the effect of self-sealing. After performing the pressurized pressure, the pressure is relieved first in the well to the value of the blocking pressure, while the piston 4 is gradually from the action of the support 10, which interacts with the depressing elements 13

10 or 15 moves upward and closes the radial channels 6. Thus, the cavity of the well is separated from the cavity 7.

However, the sealing element 11

15 is still deformed, since the packer pressure is maintained in the pipe string and cavity 9. After relieving the pressure in the well, the pressure in the drill string is relieved, resulting in

20, the sealing element 11 gradually returns to its original position due to the effects of elements 13 or 15. After equalizing the pressures in the drill string and in the well

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sleeve 18 is returned to its original position, as a result of which radial channels 22 bore hydraulically in communication with the cavity of the sealing element and, consequently, with the drill pipe string.

If necessary, interval testing device is raised higher. At the same time, fluid from the drill pipe string through the cavity 7, channel 3, hole 19, cavity of the upper stage 17 and radial channels 22 is poured into the well, which ensures lifting and unscrewing the pipes without a siphon. The test procedure is the same with the next drop of the ball 21, i.e. each test in the new interval requires the throwing of another ball 21, in connection with which the cavity 28 of the cup 26 has the necessary size to accommodate several balls.

Claims (1)

Invention Formula An apparatus for testing a casing for leak tightness in a well, including a housing with radial channels, mounted on the outer surface of the housing with the possibility of limited axial movement and interaction with the sealing element piston, a support connected to the housing and located under the sealing element, and installed in the axial channel body under saddle ball, characterized in that, in order to improve efficiency in operation by providing t multiple crimping with the exception of hydraulic strokes, it is provided with a stepped rigidly connected with the lower part of the support in the upper part along the inner surface with a nozzle with an axial channel and radial channels in the upper part and a cup spring-loaded relative to it in the lower part of the nozzle cavity, and the saddle for the throwing ball is made in the form of a stepped sleeve located in the upper part of the nozzle, is spring-loaded relative to it and installed with the possibility of overlapping its side surface of a greater degree of radial channels of the nozzle in the work than the position of the device. fi & 2