RU1798476C - Device for well wall treatment - Google Patents

Abstract

Usage: ensuring recovery of well productivity. SUMMARY OF THE INVENTION: the device comprises a housing with an axial channel and radial openings. They are equipped with scrapers and hydraulic nozzles with the possibility of their radial movement from the housing. The housing is made with an annular groove on the outer surface and a channel with a check valve. Hydraulic seals are placed in the annular groove of the housing, the cavities of which are in communication with the axial channel of the housing. A channel with a non-return valve communicates the space between the nozzles and the lower seal with the external space. 2 C.p. f-ly, 2 ill.

Description

The invention relates to drilling equipment, in particular to devices for restoring well productivity, for example, water intakes.

The purpose of the invention is to increase the intensity of the processing of the borehole wall, as well as the quality of the treatment.

Fig. 1 shows a device for treating a well during a period of increasing pressure of the working fluid, when the hydraulic seals come into contact with the wall of the well and the processing tools begin to extend from the housing; figure 2 is a section aa in figure 1.

The device comprises a housing 1 with an axial channel 2, hydraulic seals 3 located above and below the outer surface of the housing, radial holes in the housing between the seals in which the hydraulic nozzles 4 are mounted and mechanical impact elements on the borehole wall - scrapers 5.

The hydraulic nozzles and scrapers can be arranged in several planes, and mounted on the piston elements 6 in the wall of the housing 1. Hydraulic seals 3 are mounted on the surface in niches 7 with the possibility of movement in them along the housing and around the circumference of the housing. The inner cavities of the seals are in communication with the axial channel 2 by channels 8. In the wall of the housing, channels 9 and 10 are made. The channels 9 communicate the space between the nozzles 4 and the lower seal with an external space, for example, with a space under the lower end of the housing, while the housing has a through longitudinal channel 10 Channel 10 reports portions of the well above and below the seals 3. For a one-way flow through channel 9, it is equipped with a check valve.

The fluid pressure between the seals 3 during operation is higher than in the well, so the channel 9 can be made from the lower seal to the outer space

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above the upper seal 3. In this case, channel 10 is not needed.

For the non-siphon lifting of the device from the borehole, the axial channel 2 communicates with the borehole through a channel in a spring-loaded valve 11 formed in the lower end wall of the housing.

A device on tubing (tubing) is lowered into the well to the lower boundary of the formation to be treated. Then, through the tubing, a working fluid is supplied to the device (axial channel 2}, which closes the valve 11 (the valve shutter is lowered) and expands through the channels 8 in the cavity of the seals 3 and expands them to contact the well surface. As a result, the device The working fluid also acts on the piston elements 6, pushing the tools (hydraulic nozzles 4 and scrapers 5) into the annulus. The scraper 5 interacts mechanically with the wall of the well.

The device in the well is rotated and slowly lifted by tubing. Poi. This happens the following. The seals 3 move along the length of the recess 7, the scrapers mechanically treat the wall of the well, the working fluid, expired from the nozzle 4, processes the surface of the well. Solid particles torn off by scrapers from the borehole wall are discharged through channels 9 to the borehole. The pressure in the well (equal to hydrostatic) is lower than the pressure of the fluid in the device. The pressure in the well below the device is equal to the pressure of the liquid above the device, because these parts of the well communicate through a channel 10 in the wall of the body T.

The surface of the well is treated with a jet of working fluid emanating from the nozzle 4 from a close distance, since the hydraulic nozzle 4 mounted on the piston b, under the pressure of the fluid has the ability to extend to the wall of the well. The processing distance is automatically adjusted due to a change in the resistance to exit the nozzle depending on the distance from it to the surface to be treated, which is facilitated by the end shape of the nozzle, see figure 1.

In the flooded state, due to the small distance to the surface to be treated, the liquid jet almost does not lose energy. As a result of this, a high-speed jet of working fluid quickly and efficiently treats the surface. In case of ys

When the device is used in water wells, the working fluid is water, and then the mud layer is removed from the surface of the aquifer. If the working fluid is a clay solution, then the solid particles penetrate well into the rocks and form an even, strong crust, by soiling, for example, an aquifer. Non-adhering particles are carried away by a high-speed flow along

channel 9.

After the supply of working fluid to the device is stopped, the valve 11 moves away from the seat and the fluid is able to flow out of the tubing when they are lifted. This leads to a non-siphon lifting device.

Claims (3)

1. Wall treatment device well, comprising a housing with an axial channel and radial holes with scrapers and hydraulic nozzles placed in them with the possibility of radial movement, moving from the housing, characterized in that, in order to increase the intensity of processing the wall of the well, it is equipped with hydraulic seals, the cavities of which are communicated with the axial channel of the housing, the housing is made with an annular a groove on the outer surface and a channel with a check valve communicating the space between the nozzles and the lower seal with the outer space, the hydraulic seals being placed in the annular groove of the housing with the possibility of axial movement relative to the latter. 2. The device according to claim 1, wherein the channel with a check valve communicates the space between the nozzles and the lower seal with the space under the lower end of the housing, and the housing has a through longitudinal channel. 3. The device according to claim 1, with the fact that in the lower end of the housing there is a channel with a spring-loaded valve, which communicates the axial channel of the housing with the space under its lower end. Fie. 1