RU2229016C2 - Device for secondary opening and creating depression upon a layer - Google Patents

Abstract

FIELD: oil extracting industry. SUBSTANCE: device has body, depression and slag-accumulating chambers with reciprocal valve, compacting and shear elements, means for lowering and raising and perforated shank. Body is made with a shelf on upper part and with two rows of radial channels which are overlapped by upper spring-loaded bushing in default position, and is also equipped with a nipple. Radial channels are separated by solid transversal wall. Nipple is made with upper and lower ring- shaped stops, between which through apertures are made with fixing balls mounted in them. Nipple is connected to perforated shank and is also telescopically connected to the body. In default position fixing balls are engaged with lower bushing on the outer side. Lower bushing is connected to the nipple by a shear element, and spherical grooves are made on outer surface of body. Upper and lower bushings are made with cylindrical groove on inner surface and are mounted with possible longitudinal displacement. Lower ring-shaped stop of nipple is equipped with packing elements, and its outer diameter is selected to fit inner diameter of mounting bushing. Perforated shank is equipped with solid stop with a shelf and fixing ring on outer surface. Mounting bushing is connected to body of supporting assembly by a shear element, said body being a part of casing string. Outer diameter of solid stop is selected to fit inner diameter of condensing funnel. As depression and slag-accumulating chambers means for lowering and raising of device is used. Condensing funnel is mounted in cylindrical bore of mounting bushing of supporting assembly and is connected to it by shear element for engaging solid plugs mounted in casing string oppositely to productive layer. EFFECT: increased functional capabilities. 1 dwg

Description

The invention relates to the oil industry and can be used as equipment for the secondary opening of productive formations in oil and gas wells, for cleaning the bottom-hole zone of the formation and the bottom of the wells from sludge, sand, paraffin, resins and other hard to remove deposits, as well as for blocking the trunk wells.

A device for cleaning wells by the implosion method is known, consisting of an implosion chamber, which is attached to a wireline cable through an electronic unit and a geophysical headgear. A load rod is suspended in the upper part of the implosion chamber, and in the lower part there is a stepped rod connected to the centering sleeve with the possibility of overlapping cams in the transport position and interacting with the weight rod to release the glass from engagement with the sub [1].

The disadvantages of the device are:

- low efficiency of the device, due to the fact that when you open the implosion chamber, the latter will be filled mainly with well fluid, and not with sludge and formation fluid;

- high cost of the device, due to the use of electronic equipment and wireline cable;

- limited functionality.

Closest to the technical nature of the proposed device is a depression well cleaning device containing a housing, a depression chamber and a slurry chamber with a check valve, a perforated shank, sealing and shear elements, a means for lowering and lifting [2].

Significant disadvantages of the device are:

- limited volume of the sludge receiving chamber and, as a result, the need for repeated descents of the device;

- limited functionality;

- the device allows to achieve a temporary effect, because after its rise, the contaminants in the wellbore will again enter the pores and channels of the reservoir and reduce its permeability;

- significant material costs.

The objective of the invention is to provide a device with an almost unlimited volume of sludge collection chamber, with wide functionality, which allows to save large material resources.

This problem is solved by the proposed device, comprising a housing, a depression and a sludge receiving chamber with a check valve, a perforated shank, sealing and shear elements, a means for lowering and lifting.

New is that the housing is made with a ledge at the top and two rows of radial channels separated by a blind transverse partition, which in the initial position are closed by the upper spring-loaded sleeve and equipped with a nipple connected to the perforated shank and telescopically with the housing; the nipple is made with upper and lower annular stops, between which there are through holes with fixing balls installed in them, in the initial position interacting externally with the lower sleeve connected to the nipple by a shear element, and from the inside, the ball bearings interact with spherical samples on the outer surface of the housing ; the upper and lower bushings are made with a cylindrical sample on the inner surface and are mounted with the possibility of longitudinal movement; the lower annular stop is equipped with sealing elements, and its outer diameter is selected for the inner diameter of the landing sleeve connected by a shear element to the body of the support unit installed in the casing string; the perforated shank is equipped with a blind stop with a ledge and a fixing ring on the outer surface, the outer diameter of the dead stop selected for the inner diameter of the knocked funnel installed in the cylindrical bore of the landing sleeve of the support unit and connected to it by a shear element for interaction with blind plugs installed in the casing a column opposite the reservoir; as a depression and sludge-receiving chambers, a means for lowering and raising the device was used.

The drawing shows the proposed device in longitudinal section.

It consists of a housing 1 with a stop 2 in the upper part, two rows of radial channels 3, separated by a blank transverse partition 4. Telescopically to the housing 1, a nipple 5 is installed, equipped with an upper 6 and a lower 7 ledges, between which through holes 8 are located around the perimeter with balls-clamps 9 installed in them, in the initial position interacting with the lower movable sleeve 10 connected to the nipple by shear elements 11. The locking balls interact from the inside with spherical samples 12 of the corpus CA 1. Inside the nipple 5 in the area of the location of the lower ledge 7, a check valve ball 13 is installed with a mesh 14. The nipple is connected to the perforated shank 15, and the latter, in turn, to the blind stop 16 with the shoulder 17 and the fixing ring 18. The lower shoulder 7 the nipple is equipped with sealing elements 19.

The radial channels 3 in the initial position are blocked by the upper movable sleeve 20, between which the spring 2 is installed and the stop 2.

The bushings 10 and 20 are made with cylindrical samples 22 on the inner surface. The mating surfaces of the parts are equipped with sealing elements 23. The length of the nipple 5 is taken so that the perforated liner 15 connected to it, when installing the device in the well, is below the perforation holes of the reservoir.

The tubing 34 is the depression chamber. The tubing 34 is formed by the tubing chamber 34, body 1, nipple 5, perforated shank 15 and blind stop 16. The tubing 34 is the means for lowering and raising the device.

The device operates as follows. A casing 24 with blind plugs 25 filled with bitumen and a support unit located above them, consisting of a housing 26, a landing sleeve 27 and a knocked-out funnel 28, which are interconnected by shear elements 29 and 30, is lowered into the well drilled to the design depth. The landing sleeve 27 has a conical surface, and the whipping funnel 28 has an annular recess 32 for the retaining ring 18. The casing 24 is installed so that the blind plugs 25 are opposite the reservoir 33. Then, the well is cemented in a known manner and after OZZ (waiting for the hardening of cement) inside the casing string on the tubing (tubing) 34 lower the proposed device. When it moves down, the blank stop 16 enters the knockout funnel 28, while the retaining ring 18 enters the recess 32, under the action of the load, the shear elements 30 are destroyed, the tubing with the device and the knockout funnel continue to move down and destroy the blank plugs 25. With further downward movement the lower sleeve 10 will abut against the landing sleeve 27 of the support unit, and the lower ledge 7 with seals will go inside it and isolate the bottom-hole zone from the wellbore. The shear elements 11 are destroyed, the nipple 5 and the sleeve 10 are displaced relative to each other, the locking balls 9 fall into the sample 22 of the sleeve 10 and release the housing 1, which is lowered all the way into the mesh 14. In this case, the radial holes 3 in the housing 1 are installed opposite the sample 22 sleeve 20, after which there is a communication of the bottomhole zone of the well with the internal space of the tubing under atmospheric pressure. A deep depression is created on the reservoir, as a result of which the channels in the hollow plugs 25 are opened, the reservoir is opened and cleaned of impurities, sludge and liquid that got into the reservoir during the initial opening of the reservoir, which through the holes in the liner 15, check valve 13, the central channel of the body , radial channels 3 and a sample 22 of the sleeve 20 fall into the tubing. After implosion treatment, the tubing is lifted, and with them the body 1, the sleeve 20 and the spring 21, while under the influence of the latter, the sleeve 20 overlaps the radial channels 3. All other nodes of the device remain in the well.

Depression on the formation can be controlled by pouring the calculated volume of fluid into the tubing.

Then a pump is lowered into the well and development and operation are carried out in the usual manner.

The landing sleeve 27 and the whipping funnel 28 are made of drillable material, such as cast iron.

If it is necessary to conduct work below the reservoir (deepening the wellbore, cutting the second wellbore, etc.), the equipment left there is lifted from the well, drill the bushing 27 and drill the wellbore with a diameter equal to the inner diameter of the casing.

The proposed device allows you to carry out a whole range of work after drilling a well for one run-up of tubing using one device, namely: re-opening the reservoir, cleaning the formation and bottomhole zone from sludge and contaminants and blocking the wellbore. Due to this, significant material resources will be saved. Unlimited slurry chamber volume reached. After the tubing is lifted, the reservoir is isolated from the wellbore with a nipple with a check valve, and therefore the negative effect on the reservoir of water, kill fluid and contaminants in the wellbore is eliminated. In addition, the presence of a shank installed below the perforation holes contributes to the creation of a water seal from the oil opposite the reservoir for the entire period of operation and thereby dramatically reduces the percentage of water production from the bottom of the reservoir.

Information used

1. RF patent No. 2086753, MKI 6 E 21 V 37/00, 1997 (analogue).

2. RF patent No. 2099506, MKI 6 E 21 V 37/00, 1997 (prototype).

Claims (1)

A device for re-opening and creating depression on the formation, including a housing, a depression chamber and a sludge receiving chamber with a check valve, a perforated shank, sealing and shear elements, means for lowering and lifting, characterized in that the housing is made with a ledge at the top and two rows of radial channels, separated by a blank transverse partition, which in the initial position are covered by the upper spring-loaded sleeve, and is equipped with a nipple connected to the perforated shank and telescopically with with a mustache, the nipple is made with upper and lower annular stops, between which there are through holes with fixing balls installed in them, in the initial position interacting externally with the lower sleeve connected to the nipple by a shear element, and from the inside with spherical samples made on the outer surface of the housing , the upper and lower bushings are made with a cylindrical selection on the inner surface and are mounted with the possibility of longitudinal movement, the lower annular stop is equipped with sealing elements tam, and its outer diameter is selected for the inner diameter of the landing sleeve connected by a shear element to the body of the support unit installed in the casing string, the perforated liner is equipped with a blind stop with a step and a retaining ring on the outer surface, and the outer diameter of the dead stop is selected for the inner diameter a whipping funnel installed in a cylindrical bore of the landing sleeve of the support unit and connected to it by a shear element for interaction with blind plugs installed in garden column opposite the reservoir, as a depression and sludge collection chambers, a means for lowering and lifting the device was used.