RU66409U1 - DEVICE FOR CLEANING THE INTERIOR SURFACE OF THE COTTING PIPE - Google Patents

Abstract

The proposal relates to the field of drilling equipment, namely, devices for overhaul of wells. A device for cleaning the inner surface of the casing pipe contains a housing with a sub for mounting the downhole motor and a sub for mounting the bit. Pistons with o-rings, which provide tightness, are placed inside the housing with the possibility of a limited focus. Pistons are rigidly connected to the cutting elements. The central channel of the housing below the pistons is equipped with an adjustable constriction, made in the form of a calibrated hole of the replaceable sleeve. The lateral surface of the cutting element, cleaning the casing, in the cross section is made in the form of a pointed star. The number of rows of cutting tools located in one radial plane may be more than one. The proposed design of the utility model is simple and technological, made with the possibility of different locations of the cutting elements with an increased service life on the outer surface of the body during drilling. 2 ill. for 1 liter

Description

The proposal relates to the field of drilling equipment, namely, devices for overhaul of wells.

It is known "Device for cleaning the walls of the well" (AS No. 1186788, ЕВВ 37/00, publ. Bull. No. 39 from 10.23.1985), containing a housing with radial holes, an elastic annular shell overlapping radial holes, limiters deformations, scraper elements installed with the possibility of movement in the radial direction, while it is equipped with pushers, some ends of which are connected with an elastic annular shell, and others with scraper elements, moreover, an annular cavity is made in the housing to accommodate elastic rings oh shell, and the scraper elements are placed in deformation limiters.

The disadvantages of this device are:

- low reliability due to high requirements for tightness of the elastic shell;

- low productivity due to the small radial force on the scraper elements created by the elastic shell;

- the inability to use in the drilling process, since the passage section of the central channel is not regulated.

It is also known “Device for cleaning the inner surface of the casing pipe” (AS No. 715773, ЕВВ 37/02, publ. Bull. No. 6 of 07/21/1980), comprising a housing with a central channel, retractable cutting elements, rigidly connected with a piston mounted for axial movement, while the inclined side channels are made in the housing, and the piston is made with axial and radial channels that periodically communicate with the channels in the housing.

The disadvantages of this device are:

- low reliability and high price due to the complexity of the manufacture and location of the axial and lateral inclined channels of the housing, as well as axial and radial channels of the piston;

- low productivity due to the small radial force on the cutting elements, since the radial channels of the piston periodically interact with the channels in the housing when extending the cutting element with the piston;

- poor centering, since due to the complexity of the design, the cutting elements can only be positioned floor and symmetrical in plan;

- poorly destructible deposits from the well due to the lack of constant fluid circulation;

- the inability to use when drilling cement stone in the composition of the drilling tool, since the Central channel is not through.

The closest in technical essence and the achieved result is a "Device for cleaning the inner surface of the casing" (patent RU No. 2099507, ЕВВ 37/02, publ. Bull. No. 35 dated 12/20/1997), including a housing with a central channel and retractable cutting elements associated with a spring-loaded piston axially moving in the housing, it is provided with a wedge configured to interact with the piston, the working surface of the wedge being provided with grooves corresponding to the protrusions of the cutting elements, and the angle when its top exceeds the angle of friction between the materials of the working surfaces of the wedge and the cutting elements, and the working surface of the cutting elements can be made in the form of multiple cylindrical threads.

The disadvantages of this device are:

- high price due to the complexity of manufacturing grooves on the wedge, reciprocal protrusions of the cutting elements;

- low possibility of transformation, since the number of cutting elements that can be located only in one radial plane is strictly related to the number of grooves on the wedge;

- cleaning is carried out only by one edge of the cutting element, which reduces its resource.

The technical task of the proposed utility model is a simple and technological device with the possibility of different locations of the cutting elements on the outer surface of the body during drilling, as well as an increase in the resource of the cutting element due to the use of its entire perimeter.

The technical problem is solved by a device for cleaning the inner surface of the casing, including a housing with a Central channel and retractable cutting elements associated with mounted in the housing with the possibility of movement by a spring-loaded piston.

New is that each cutting tool is rigidly connected to the corresponding piston spring-loaded inside, made with the possibility of limited radial movement from the inside of the housing, the central channel of which is equipped with adjustable constriction below the pistons, and the side surface of the cutting element cleaning the casing is made in cross section in the form of a pointed star.

Also new is the fact that the number of rows of cutting tools located in one radial plane is more than one.

Figure 1 shows a General view of the proposed device in axial section with one row of cutting tools.

Figure 2 shows a cross section of a portion of a cutting element cleaning the casing.

A device for cleaning the inner surface of the casing pipe includes a housing 1 (see Figure 1) with a sub 2 for mounting a downhole motor (not shown) and a sub 3 for attaching a bit (not shown). Inside the housing 1 with the possibility of a limited emphasis 4 there are placed pistons 6 pressed by a spring 5 inside the housing 1 with sealing rings 7, which ensure tightness. The pistons 6 are rigidly connected to the cutting elements 8. The central channel 9 of the housing 1 below the pistons 6 is equipped with an adjustable restriction 10, made in the form of a calibrated hole 10 of the replaceable sleeve 11. The number of rows 12 of cutting tools 8 located in one radial plane may be more than one. The lateral surface 13 (see Figure 2) of the cutting element 8, cleaning the casing, in the cross section is made in the form of a pointed star with cutting edges 14.

During operation, the device is placed between the downhole motor and the bit, which are attached to the housing 1 (see Figure 1) using the corresponding sub 2 and 3, and placed in a repaired casing (not shown).

The device operates as follows.

During operation of the bit, fluid circulates inside the housing 1, which, thanks to the calibrated hole 10 of the replaceable sleeve 11, creates excessive pressure in the central channel 9, which moves the pistons 6 out of the housing 1 until the stop 4 interacts with the housing 1 together with the cutting elements 8. The downhole motor leads the housing 1 with a chisel into rotation. Rotating with the housing 1, the cutting elements 8 clean the inner surface of the casing from deposits and / or cement stone (not shown). In this case, the pistons 6 with the cutting elements 8 rotate in the housing, rolling along the side surface 13 (see Figure 2) over deposits and / or cement stone,

and cutting edges 14 destroy them, using to increase the resource the entire side surface 13 of the cutting element 8. Such destruction is most effective for uniform deposits and / or cement stone. Upon completion of the work, the liquid through the central channel 9 (see FIG. 1) ceases to circulate and the springs 5 return the pistons 6 with the cutting elements 8 to their original state.

To improve the quality of processing the inner surface of the casing string, the number of rows 12 of cutting tools 8 located in one radial plane is more than one (from practice no more than three rows 12 are sufficient). Moreover, for high-quality centering of the device in the casing in row 12, three cutting tools are sufficient 8. The number of cutting elements 8 is selected depending on the required quality of processing the inner surface of the casing, instead of unused cutting elements 8 with pistons 6, plugs are installed (not shown in Fig.) .

The use of replaceable sleeves 11 with a calibrated bore 10 allows you to select the excess pressure acting on the pistons 6, sufficient to extend them from the housing 1 (the lower the fluid circulation rate in the central channel, the narrower the bore 10).

The proposed design of the utility model is simple and technological, made with the possibility of different locations of the cutting elements with an increased service life on the outer surface of the body during drilling.

Claims (2)

1. A device for cleaning the inner surface of the casing pipe, comprising a housing with a central channel and retractable cutting elements associated with a spring-loaded piston mounted in the housing with the ability to move, characterized in that each cutting tool is rigidly connected to a corresponding piston spring-loaded inside, made with the possibility of limited radial movement from the inside of the body, the central channel of which is equipped with adjustable narrowing below the pistons, and the side surface of the cutting element, estvlyayuschaya cleaning casing in cross section is formed as a pointed star. 2. The device for cleaning the inner surface of the casing according to claim 1, characterized in that the number of rows of cutting tools located in one radial plane is more than one.