RU44732U1 - DEVICE FOR CLEANING WELL BORE - Google Patents

Abstract

The proposal relates to the oil industry and can be used to clean the bottom of oil, gas and injection wells after drilling, as well as for ongoing and major repairs of wells. The device consists of a hollow body with a guide sleeve in its upper part. A hollow plunger plugged from the lower end is sealed into the guide sleeve with the possibility of axial movement downward. The upper end of the plunger is connected to the lower open end of the tubing string. Radial through holes are made in the side walls of the lower part of the plunger introduced into the housing. An annular bead is made in the upper part of the outer surface of the plunger located outside the housing. An annular stop is mounted on the outer surface of the plunger, which is connected in the transport position to the plunger by means of a shear element. Between the annular stop and the upper end of the guide sleeve of the housing placed packer seal with emphasis on the bottom. The technical and economic effect is to reduce material costs for the manufacture of the device by simplifying the design of components and parts, and guaranteed seating of the packer seal with emphasis on the bottom in the working position will improve the reliability of its operation. Using the plunger as a container will improve the efficiency of bottomhole cleaning, since the reverse loss of sludge and sand into the well is prevented due to the forced overlapping of the through radial channels in the transport position.

Description

The proposal relates to the oil industry and can be used to clean the bottom of oil, gas and injection wells after drilling, as well as for ongoing and major repairs of wells.

A device for cleaning the bottom of a well from sand plugs (Lavrushko PN Underground repair of a well. M., Nedra, 1968, p. 281-282, Fig. 149), which consists of a hollow body with a guide sleeve in its upper part, a piston with a rod mounted on the lower end of the intake valve body and placed on the spring rod. For loosening sand plugs at the end of the device, an additional baking powder tool is provided, made, for example, in the form of peaks with a conical head, under which a landing saddle is made in the lower part of the housing. In the piston body of the device, longitudinal bypass channels are made for fluid flow from the lower part of the device (from under the piston) to the upper part. From the upper end of the piston, a cap is freely installed on the rod to block the channels in the piston. And for depreciation during the stroke of the rod in the upper and lower positions, the springs are installed on the rod in a free (unloaded) state: one outside the housing and the other in the housing. At the upper end of the device there is an eyelet for attaching the tartar rope, on which this device descends into the well for work and rises to the surface.

The disadvantages of this device are:

- the presence of longitudinal bypass channels in the piston body and the cover for their overlap does not ensure the tightness of the device during operation due to clogging with sand, which reduces its reliability;

- the complexity of the design, due to the large number of nodes and parts;

- low efficiency, because the device does not provide for one descent to completely fill its internal cavity with sand, in addition, the volume of the hollow body of the device into which sand is sucked is limited by the dimensions of the device itself. Therefore, to eliminate sand plugs, the device must be lowered and raised to the surface repeatedly, which also leads to wear of the tartar rope.

The closest in technical essence to the proposed is a device for cleaning the bottom of the well (see RF patent No. 94032467, MKI 7 E 21 B 27/00), including a hollow body with a guide sleeve in its upper part, a rod inserted through the guide sleeve into the body, a piston connected to it, a receiving valve mounted on the lower end of the housing and a spring placed on the rod, the piston and rod being made as a single hollow plug plugged from the lower end with an outer diameter less than the inner diameter of the housing, and the upper the end of the plunger is connected to the lower open end of the tubing string, while the lateral holes are made in the side walls of the lower part of the plunger, radial through holes are made on the outer surface outside the upper part of the plunger, and a spring is installed between the upper end body and annular collar of the plunger in a state of pre-compression. The housing in its lower part above the intake valve is detachable and axially displaceable into the intake valve housing, while on the outer surface of the housing there is a thrust shoulder, between which and the upper end of the intake valve housing there is a packer seal with emphasis on the bottom.

A significant disadvantage of this device are:

- the complexity of the design, due to the large number of components and parts, in addition, in the design of the device one of the main working elements is a spring in a state of preliminary compression, which when the device is lowered into the well and during its operation is subject to significant alternating loads, which can lead to its breakdown, and consequently the loss of operability of the entire device;

- low reliability of the packer seal landing with emphasis on the bottom, since when unloading the tubing string onto the device, after compressing the spring, the radial through holes of the plunger can open earlier than the packer seal landing, and this leads to a significant decrease in the device’s efficiency ;

- it is possible that the receiving valve is not tightly closed due to jamming, which during the lifting of the device will lead to the loss of sand and sludge back into the well and to a decrease in the efficiency of cleaning the bottom hole.

The objective of the utility model is to reduce material costs for manufacturing the device by simplifying its design and increasing the reliability of packing packer seals with emphasis on the face and the efficiency of cleaning the face.

The specified technical problem is solved by the proposed device for cleaning the bottom of the well, including a hollow body with a guide sleeve in its upper part, hermetically sealed with the possibility of axial movement downward through the guide sleeve into the body, a hollow plug plugged from the bottom end, equipped in the side walls of the bottom part radial through holes, and on the outer surface located outside the housing in the upper part - an annular collar, packer seal.

What is new is that it is equipped with an annular stop and a shear element mounted on the outer surface of the plunger below the annular collar, the shear element fixes the annular stop with the plunger in the transport position, and a packer seal is installed between the upper end of the guide sleeve of the housing and the above annular stop.

Figure 1 shows the proposed device in longitudinal section, lowered into the well.

The device consists of a hollow body 1 with a guide sleeve 2 in its upper part. In the guide sleeve 2 hermetically inserted with the possibility of axial movement down hollow muffled from the lower end of the plunger 3.

The upper end of the plunger 3 is connected with the lower open end of the string of tubing 4. Radial through holes 5 are made in the side walls of the lower part of the plunger 3 inserted into the housing 1. An annular bead 6 is made in the upper part of the outer surface of the plunger 3 located outside of the housing 1 On the outer surface of the plunger 3 below the annular flange 6 is installed an annular emphasis 7, connected in transport position with the plunger 3 by means of a shear element 8.

Between the annular stop 7 and the upper end 9 of the guide sleeve 2 of the housing 1, a packer seal 10c is placed focusing on the bottom.

The device operates as follows.

To clean the bottom of the well or to eliminate plugs in the well, the upper part of the plunger 3 of the device is fixed at the lower end of the tubing string 4 (see Fig.), After which the device on the tubing string 4 is lowered into the well in the cleaning interval.

When the lower part of the housing 1 touches the sand plug or the bottom of the well, it stops its downward movement, and the plunger 3, under its own weight and the weight of the tubing string 4, begins to move down, and at a certain moment at the calculated load (due to the unloading of the tubing string -compressor pipes 4 on

device) the shear element 8 is destroyed, as evidenced by the indication of a weight indicator located at the wellhead (not shown in FIG.).

As a result of this, the radial through holes 5 of the plunger 3 exit the guide sleeve 2. The inner cavity 12 of the housing 1 through the radial through holes 5 and the internal cavity 13 of the plunger 3 will communicate with the interior of the tubing string 4 and further with the atmosphere, which is simultaneously destroyed a shear element 8 with an annular stop 7 moves upward on the outer surface of the plunger 3 until it abuts against the annular bead 6, and the elastic cuffs of the packer seal 9 are pressed against the atatsionnoy column 11, thereby closing the annular space and closing of fluid access to nadpakernoe packer space, and creating a higher pressure in the range of purification.

Due to the pressure difference in the tubing string 4 and in the annular under-packer space of the well, the liquid, together with sand and slurry, enters the inner cavity 12 of the housing 1 with high speed and then through the completely open radial holes 5 and the inner cavity 13 of the plunger 3 into the inner cavity of the tubing string 4.

Thus, the process of cleaning the bottom of the well. At the same time, drainage of the sub-packer zone of the formation occurs, thereby cleaning the bottom-hole zone of the formation, accelerating its development. After cleaning the bottom or eliminating the plug in the well, the tubing string 4 begins to be lifted, while the packer seal returns to its original state, as a result of which the through radial channels 5 enter the guide sleeve 2 of the housing 1 and overlap with it, which prevents sand and sludge from falling out back to the well. Next, the device is raised to the day surface.

The technical and economic effect is to reduce material costs for the manufacture of the device by simplifying the design of components and parts, and guaranteed seating of the packer seal with emphasis on the bottom in the working position will improve the reliability of its operation. Using the plunger as a container will improve the efficiency of bottomhole cleaning, since the reverse loss of sludge and sand into the well is prevented due to the forced overlapping of the through radial channels in the transport position.

Claims (1)

A device for cleaning the bottom of the well, including a hollow body with a guide sleeve in its upper part, hermetically sealed with the possibility of axial movement downward through the guide sleeve into the body, a hollow plug plugged from the bottom end, equipped in the side walls of the bottom part with radial through holes, and on the outer surface located outside the housing in the upper part - an annular collar, a packer seal, characterized in that it is equipped with an annular stop and a shear element, is installed lennymi on the outer surface of the plunger below the annular flange, wherein a shear element fixes the annular abutment with the plunger in the transport position and the packer seal is mounted between the upper end of the guide sleeve housing and above the annular abutment.