RU78512U1 - DEVICE FOR CLEANING WELL BORE - Google Patents

Abstract

The proposal relates to the oil industry and can be used to clean the bottom of production and injection wells from sand and gypsum plugs during ongoing and major repairs of wells.

The device consists of a hollow body with a guide sleeve in its upper part. A screw shaft with a cutter-ripper at the end is installed inside the housing, and the cutter-ripper is spring-loaded by means of a spring and has the possibility of axial and rotational movement.

A bearing bracket is located inside the guide sleeve. The helical shaft above the cutter-ripper is equipped with a support nut rigidly connected to the housing. The support nut is provided with vertical through holes. The bottom case is equipped with teeth, and the outside is equipped with a self-sealing cuff, which lets it pass from the bottom up, and radial holes made in the pipe above the self-sealing cuff. The screw shaft inside is equipped with a channel communicating the space above the cutter-ripper with the inner space of the pipe string on which the device is lowered.

The proposed device can significantly increase the efficiency of cleaning wells from gypsum and sand plugs due to the movement of the cutter-ripper, as well as the simultaneous drilling, grinding and washing.

1 ill. for 1 liter

Description

The proposal relates to the oil industry and can be used to clean the bottom of production and injection wells from sand and gypsum plugs during 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, for example, made 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 to the highest and lowest 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:

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

- secondly, the presence of longitudinal bypass channels in the body of the piston and the cover for their overlapping due to clogging with sand does not provide tightness during operation, which reduces the reliability of the device.

The closest in technical essence to the proposed is a device for cleaning the bottom of the well (see RF patent for utility model No. 57343, IPC 7 Е21В 27/00 publ. In Bulletin No. 28 of 10/10/2006), including a hollow body with a guide a 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 with radial through holes introduced into the hollow body, a receiving valve, while between the hollow

a fitting with an adjustable bore diameter is mounted on the housing and the intake valve, and a nozzle with a tapered lower end is installed under the intake valve, while in the transport position the plunger is fixed relative to the guide sleeve of the hollow body by a shear element.

The disadvantages of this device are:

- firstly, before cleaning the bottom of the well, the nozzle abuts against the bottom to be cleaned with its beveled lower end and if the bottom is “hard”, it is very difficult to loosen it, which very sharply reduces the ingress of sand, gypsum, sludge, and dirt from the bottom of the well,

- secondly, with intensive lifting of washed-out sludge, gypsum, sand, the throughput of the adjustable nozzle may not be sufficient for the stable operation of the device, that is, the flow is blocked under the adjustable nozzle inside the device. All of the above reduces the efficiency of the device

The objective of the utility model is to increase the efficiency of cleaning the bottom of the well without complicating the technology of using the device.

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.

What is new is that a helical shaft with a cutter-ripper at the end is installed inside the case, and the cutter-ripper is spring-loaded upward and has the possibility of axial and rotational movement, while the case is equipped with teeth from the bottom and equipped with a self-sealing cuff, which passes from the bottom up, and radial holes made above the self-sealing cuff, with a bearing support installed inside the guide sleeve, and the helical shaft above the cutter-ripper is equipped with a support nut rigidly connected to the housing and equipped with vertical through holes, and a screw shaft fitted inside the passageways communicating the space above the ripper cutter with the interior of the tubing string in which the device goes down.

The figure schematically shows the proposed device in longitudinal section.

The device consists of a hollow body 1 with a guide sleeve 2 in its upper part. Inside the housing 1, a helical shaft 3 is installed with a cutter-ripper 4 at the end, and the cutter-ripper 4 is spring-loaded by means of a spring 5 and has the possibility of axial and rotational movement.

Inside the guide sleeve 2 there is a bearing support 6. The helical shaft 3 above the cutter-ripper 4 is equipped with a support nut 7, rigidly connected to the housing 1.

The supporting nut 7 is provided with vertical through holes 8.

The housing 1 from the bottom is equipped with teeth 9, and from the outside it is equipped with a self-sealing cuff 10, which passes from the bottom up, and radial holes 11 made in the pipe 3 above the self-sealing cuff 10.

The screw shaft 3 inside is equipped with a channel 12, which communicates the space 13 above the cutter-ripper 4 with the inner space 14 of the pipe string 15, on which the device is lowered.

The device operates as follows.

To clean the bottom of the well 16, for example, from a gypsum plug 17, the complete assembly is fixed (see Fig.) At the lower end of the pipe string 15, for example, a tubing string (not shown) and lowered into the well to the support on gypsum plug 17.

As soon as the housing 1 with teeth 9 rests against the bottom of the well, as evidenced by the beginning of the unloading of the device, which is reflected in the readings of the weight indicator (not shown in Fig.) Installed at the wellhead.

After that, the well 16 is filled with process fluid and the device is completely unloaded with the tubing string onto the gypsum plug 17, while under the influence of the weight of the device, the mill-ripper 4 with a screw shaft 3 rotates by means of a bearing support 6 located inside the guide sleeve 2 and the mill-ripper 4 begins to go deeper into the sand cork 17, destroying it.

At the time of unloading the device on the gypsum plug 17, the housing 1 with teeth 9 is fixed on the processed gypsum plug 17, while eliminating the reactive moment from the rotation of the cutter-ripper 4.

Next, the process fluid is injected into the annular space 18 of the well 16, while the process fluid from the annular space 18 of the well 16, since the self-sealing sleeve 10 is pressed against the inner walls of the well 16 through the radial holes 11 of the casing 1, enters the casing 1, that is, into the space 13 above the cutter-ripper 4 and loosened by the cutter-ripper 4 eroded gypsum begins to flow through the channel 12 into the screw shaft 3, which rises up and enters the inner space 14 count nna tubing 15. After washing off the loosened ripper cutter 4 gypsum from the space 13, a spring 5 returns the ripper cutter-4 to its initial position (dashed lines shows the location-ripper cutter 4 in the initial position).

Thus, cyclically by axial movements of the device up and down, combining this with the supply of process fluid to the annular space 18 of the well 16, and washing out the gypsum loosened by the cutter-ripper 4, the bottom of the well is cleaned until the penetration is completely stopped. After cleaning the bottom of the well, the tubing string 15 together with the device is raised to the surface.

The proposed device can significantly increase the efficiency of cleaning wells from gypsum and sand plugs due to the movement of the cutter-ripper, as well as the simultaneous drilling, grinding and washing.

Claims (1)

A device for cleaning the bottom of the well, comprising a hollow body with a guide sleeve in its upper part, characterized in that a helical shaft with a cutter-ripper at the end is installed inside the body, the cutter-ripper is spring-loaded upward and has the possibility of axial and rotational movement, while it is equipped with teeth at the bottom, and on the outside it is equipped with a self-sealing sleeve, which lets it pass from the bottom up, and radial holes made above the self-sealing sleeve, and a bearing bearing is installed inside the guide sleeve ora, as above-screw shaft provided with a ripper cutter bearing nut rigidly connected to the housing and provided with a vertical through-hole, and a screw shaft fitted within channels communicating space above ripper cutter with the interior of the tubing string in which the device goes down.