RU1786244C - Device for cleaning inner surface of pipe string - Google Patents

Abstract

SUMMARY OF THE INVENTION: The scraper body is integral. Its upper part has the shape of a bell and is equipped with a cathode insert, a ferromagnetic ring and a check valve. Its lower part is fixedly mounted above the ESP and has a dielectric cylindrical sleeve, a perforated baffle with the central electrode of the electrolyzer, a magnetic seat, an electric contact, and a rectifier bridge. After the upper part of the housing is filled with electrolysis products, it rises to the upper limiter. The scraper control unit located on the upper stop opens the non-return valve. The upper part of the scraper body is released from the electrolysis products, and it is lowered onto the magnetic seat located in the lower part of the body. To give the device additional reactive power, it can be equipped with a gas igniter. 1 ill. (L C

Description

The invention relates to the oil industry, to devices for cleaning the inner cavity of pipe columns from paraffin hydrate formation due to their continuous removal.

A device is known for cleaning lift pipes from paraffin during plunger operation of oil wells, comprising a housing with a scraper in the upper part and a valve with ratchet, with a bimetallic plate resting against it, in the lower part.

A significant disadvantage of the known device is that it can move up only under the action of the dynamic pressure of the fluid flow of significant magnitude, because due to relatively large weight and small volume

device, buoyant (Archimedean), the strength of the well fluid is negligible. The closest in technical essence to the claimed is a flying automatic scraper, comprising a housing with cleaning elements, upper and lower limiters of movement and a control unit for the scraper.

A disadvantage of the known device is that it does not sufficiently utilize the buoyancy (Archimedean) force of the well fluid.

The aim of the invention is to increase the efficiency of preventing paraffin hydrate formation and their removal in low-production wells equipped with electric centrifugal pumps.

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The goal is achieved in that the device is equipped with an electrolyzer located in the body of a flying automatic scraper and made of two parts, the upper part of which is movable and has the shape of a bell, on the outer surface of which there are cleaning elements, and its lower part is motionlessly placed above electric centrifugal pump and made in the form of a cylindrical sleeve and a perforated partition made of dielectric materials, the electrolyzer is made in the form of a central electrode with a rectifier bridge located in the dielectric partition, and a cathode insert located in the bell, while the rectifier bridge is electrically connected to the electric centrifugal pump and the central electrode, an equation unit in the form of an outlet check valve installed in the upper part of the bell and located on the upper limiter , a magnetic unit for interacting with the check valve during the release of the bell from the gas component of the electrolysis products, and the upper limiter is made in the form perforated septum, and the lower limiter has a magnetic seat, electrical contact and a ferromagnetic ring, while the magnetic seat and electrical contact are located on the perforated dielectric partition, and the ferromagnetic ring is located on the lower end of the bell, and the scraper body is provided with a ring-shaped movable stop for interaction with by paraffin-hydrate formation in the places of narrowing the passage section of the column of lifting pipes located above the upper part of the bell and a gas igniter Mounted in the upper part of the bell with the ability vgzimodeystvi koltseoobraznym the movable abutment.

The implementation of the upper part of the device - the housing of a flying automatic scraper in the form of a bell will ensure the collection in its cavity of gases released during electrolysis. Electrolysis will be performed after the housing, having lowered to the lower limiter and pressed to the electrical contact with a magnetic seat, closes the contact, creating a potential difference between the central electrode and the cathode insert of the housing.

The perforated baffle of the lower part provides the passage of oil, and the implementation of its dielectric allows you to fasten the central electrode in it with

rectifier bridge, magnetic seat and electrical contact ..

The installation of a rectifier bridge in the perforated baffle provides a constant positive potential to the central electrode, and a negative potential to the electrical contact and the borehole walls, and when the housing is seated on the magnetic seat and the electrical contact is closed through the ferromagnetic ring of the housing to the cathode insert, it provides automatic the beginning of the electrolysis of the aqueous component of the reservoir fluid with the collection of gaseous electrolysis products in the bell housing.

A cylindrical sleeve made of a dielectric material protects the walls of the pipe string in their lower part from electrolysis damage when the casing emerges.

A ring made of ferromagnetic material attracts and retains the casing. On the magnetic seat. This ensures that the gas volume in the body of the flying scraper is collected not only to create positive buoyancy of the device that compensates for its weight, but also to excess buoyancy necessary to overcome the magnetic interaction force of the magnetic cusp with a ferromagnetic ring, which will provide a more intense lift of the flying scraper and the creation of the necessary efforts on the treatment elements.

The installation of an exhaust check valve in the upper part of the casing of the flying automatic scraper ensures that it interacts with a magnetic assembly located on the upper limiter for the period of release of the casing from the gas component of electrolysis products. At the same time, the magnetic assembly ensures that the body of the flying, automatic scraper is held until the weight of the latter overcomes not only the positive buoyancy forces of the gaseous product volume residues in it, but also the magnetic attraction forces, which eliminates the possibility of the body hanging at the upper limiter and allows carry out a more intensive descent of the body, and, accordingly, cleaning the walls of the pipes.

A gas igniter at the top of the bell ignites the gaseous products of the electrolysis reaction in the cavity of the housing to give the latter an additional reactive force at the points of narrowing the passage section of the riser string with paraffin hydrate formation.

A gas igniter is driven by a mechanically connected movable annular stop mounted in the upper part of the bell and in direct contact with paraffin hydrate constrictions.

Thus, the features listed above are essential, ensuring the operability of the device and meeting the criterion of novelty.

The device shown in the drawing.

The device comprises the upper and lower parts of the control unit. The upper part is the body 1 of a flying automatic scraper in the form of a bell with cleaning elements 15 on the outer surface, a cathode insert 3 inside, a ferromagnetic ring 4 in the lower part, an outlet check valve 2 and an annular movable stop 17, mechanically connected to the gas ignitor 18 , at the top, has the ability to move along the eyes of the pipe string. The lower part is fixedly placed above the electric centrifugal pump 11 and contains a perforated partition 9 made of dielectric material with a rectifier bridge 10 in it. A central electrode 6 of the electrolyzer, a magnetic saddle 7, and an electrical contact 16 are mounted on the partition 9. The positive output of the rectifier bridge 10, which removes energy from the electrical input of the electric centrifugal pump 11, is electrically connected to the central electrode 6, and the negative to the electrical contact 16 and the walls of the pipe string (ground), which in its lower part is internally protected by a cylindrical sleeve 5 of dielectric material. The control unit is made in the form of a magnetic unit 13, 14. mounted on a perforated upper limiter 12.

The principle of operation of the device is as follows.

The body of an automatic flying scraper dropped into the column of lifting pipes by its own weight is lowered down the wells, cleaning the pipe wall from paraffin-hydrate formation by the cleaning elements 15. Having reached the lower part, the body, due to the interaction between the ferromagnetic ring 4 and magnetic seat 7, is attracted and sits on last, the closure of the ferromagnetic ring 4 electrical contact 16.

Moreover, due to the fact that the rectifier bridge 10 installed in the dielectric partition 9 removes part

the voltage from the output of the electric centrifugal pump 11, and the positive and negative terminals of the bridge are electrically connected respectively to the central electrode 6 and the electrical contact 16, which, when the housing is seated on the saddle through the ferromagnetic ring 4, is electrically connected to the cathode insert 3 and the electrolysis of the water component of the borehole begins liquid in the electrolyzer, the central electrode 6 is the cathode insert 3. The process is accompanied by the release, in particular, of gaseous products that are collected in the bell le scraper body. During the process, the borehole fluid can pass through the perforation of the baffle 3. After collecting the volume of gas necessary to compensate for the weight of the scraper body and the interaction force of the ferromagnetic ring 4 with the magnetic seat 7, the scraper body 1 comes off the seat 7 and rises upwards, cleaning the pipe wall purification elements 15. In order to exclude the electrolysis process and protect the walls of the pipe columns, a cylindrical sleeve 5 of dielectric material is installed. When the scraper body 1 approaches the upper perforation stopper 12, the body 1 is attracted by a magnetic assembly 13, 14, which, holding the body, interacts with the outlet check valve 2 of the body for the period of release of the bell from gaseous products until the weight of the chamber exceeds the sum magnetic force, pressure force of the fluid flow, and buoyant (Archimedean) force of the residual gas volume. The camera opens and moves down. The cycle repeats. When paraffin-hydrate constrictions are formed in the pipe section cross-section to provide additional reactive force by burning part of the gaseous products under the bell, the movable ring stop 17 in the upper part of the scraper body 1 rests against the narrowing and mechanically drives the gas igniter 18. Installed in the upper part bells of the case, and the pressing part of gaseous products. The scraper body acquires a short-term significant impulse of energy.

Claims (2)

The economic effect of the implementation of the invention is to increase the overhaul cycle of oil wells due to the constant process of pipe cleaning, a sharp reduction in the number of shutdowns of wells with the need to clean the surface of the pipes from paraffin hydrate formation, the absence of idle strokes of the device and, in connection with this, an increase in volume produced fluid. SUMMARY OF THE INVENTION 1. A device for cleaning the inner surface of a column of lifting pipes, comprising a flying automatic scraper with a control unit, upper and lower stops and cleaning elements, characterized in that, in order to increase the efficiency of preventing paraffin hydrate formation and their removal in low-flow wells equipped with electric centrifugal pumps, it is equipped with an electrolyzer located in the body of a flying automatic scraper, and made of two parts, the upper The main part is movable and has the shape of a bell, on the outer surface of which there are cleaning elements, and its lower part is motionlessly placed above the electric centrifugal pump and made in the form of a cylindrical sleeve and a perforated partition made of dielectric materials, the electrolyzer is made in the form of a central electrode with a rectifier a bridge located in the dielectric partition and a cathode insert located in the bell, while the rectifier bridge is electrically connected to - 10 fifteen twenty 25 thirty - by an electric centrifugal pump and a central electrode, the control unit is made in the form of an outlet check valve installed in the upper part of the bell and located on the upper limiter, a magnetic unit for interacting with the check valve during the release of the bell from the gas component of the electrolysis products, the upper limiter being made in the form perforated septum, and the lower limiter has a magnetic saddle, electrical contact and a ferromagnetic ring, while the magnetic saddle and electric Contact sky raspolo- zhenyna perforated dielectric wall and the ferromagnetic ring is disposed on the lower end of the bell. 2. The device according to claim 1, with the proviso that, in order to give the scraper additional reactive force, it is equipped with a ring-shaped movable stop for interaction with paraffin hydrate formation at the narrowings of the passage section of the column of lifting pipes located above the upper part of the bell and a gas igniter installed in the upper part of the bell with the possibility of interaction with a movable ring-shaped upors