RU2370647C2 - Method of hydro-dynamic survey in well equipped with electric-centrifugal pump installation - Google Patents

Abstract

FIELD: oil and gas production.

SUBSTANCE: downhole apparatus is inserted into container for safe delivery to required depth; container is hydraulically connected with internal well space via openings and is rigidly fixed on base of electric centrifugal pump with current conducting fixing elements. Also a device for supply of inhibitors of asphalt-resin-paraffin substances and/or corrosion, and/or scale, and/or emulsion forming into well is installed into the container with the downhole apparatus. From the downhole apparatus information is transmitted to the wellhead via a power cable of an underground electric motor for intended use.

EFFECT: reduced expenditures for hydro-dynamic survey of well equipped with installation of electric centrifugal pump, increased safety of lowering downhole apparatus to required depth of well and increased operation life of well.

1 dwg

Description

The invention relates to the oil industry and can be used when conducting hydrodynamic studies of wells equipped with an electric centrifugal pump, including for the safe delivery of deep instruments to the required depth of the well. A known method of hydrodynamic research of a well, including the descent of a downhole tool into a well on a geophysical cable (patent RU 2250991 C1, 7 ЕВВ 47/00, Е21В 47/01, publ. 04/27/2005). However, it requires the presence of a geophysical cable, has a low safety descent.

The specified method is the closest to the proposed technical solution. The technical result of the invention is to reduce the cost of conducting hydrodynamic studies of a well equipped with an electric centrifugal pump, increasing the safety of lowering deep devices to the required depth of the well, increasing the life of the well. The technical result of the invention is achieved due to the fact that in the method of hydrodynamic research of a well equipped with an electric centrifugal pump installation, including transmitting information from a downhole device to the wellhead by means of an underground electric motor power cable for its intended use, the downhole device is placed in a container hydraulically connected through openings with downhole space and fixedly fixed with conductive fastening elements on the basis of electric centrifugal of the pump, while in a container with a downhole device, a device is placed for feeding inhibitors of asphalt-resin-paraffin substances and / or corrosion, and / or scaling, and / or emulsion formation into the well.

The drawing schematically shows a well with a downhole tool mounted on the bottom of an electric centrifugal pump.

The well includes an operating (casing) string 1, inside of which there are tubing 2 with an electric centrifugal pump 3, powered by a power cable 4 and connected to the container 5. Inside the container 5, a downhole device 6 is fixed in the center and connected to the bottom of the electric centrifugal pump 3 The power cable 4 passes into the annulus (between the casing 1 and the tubing 2) through the stuffing box 7 and then goes to the ground unit for accumulating and reading information (not shown). The formation fluid enters the tubing 2 from the reservoir 8. A measurement method in a well equipped with an electric centrifugal pump installation, including transmitting information from a downhole tool to the wellhead for intended use, is as follows. The depth device 6 is placed in the container 5, fixedly mounted on the base of the electric centrifugal pump 3 and lowered into the well to the required depth. Being in the flow of oil-containing fluid entering the well, the downhole tool measures its characteristics. The measurement data for the power cable 4 of the underground electric motor is fed to the wellhead in the ground-based information storage and reading unit, from which they are transmitted via wired or wireless communication devices. The following options are possible for this method, characterized in that:

- the deep device is performed directly under the electric centrifugal pump;

- the deep device is fixed on the lower part of the electric centrifugal pump;

- the bottom of the electric centrifugal pump is the base;

- the fastening elements of the downhole tool and the electric centrifugal pump are conductive;

- fastening of the deep device to the bottom of the electric centrifugal pump is threaded;

- the downhole tool is carried out in a container hydraulically connected through openings with the downhole space;

- the downhole tool is carried out in a container, which is also used to supply reagents of different consistency, chemical composition and direction of action to the well, which are inhibitors of asphalt-resin-paraffin substances and / or corrosion, and / or scaling, and / or emulsion formation;

- the container with the downhole tool is in one piece with the device for supplying to the well reagents of different in consistency, chemical composition and direction of action - inhibitors of asphalt-resin-paraffin substances and / or corrosion, and / or scaling, and / or emulsion formation;

- descent-rise in the borehole of the downhole tool is carried out together with an electric centrifugal pump;

- information is transmitted from the ground-based information storage and reading unit by means of wired or wireless communication devices.

The advantages of this method are to reduce the cost of conducting hydrodynamic studies of a well equipped with an electric centrifugal pump, increasing the safety of lowering deep devices to the required depth of the well.

The absence of a geophysical cable significantly reduces the cost of its acquisition, installation and protection against rubbing with a decentralizer. The reliability of equipment operation increases due to the lack of connections between the geophysical cable and the downhole device and problems with sealing the geophysical cable at the wellhead.

The proposed method of hydrodynamic research of a well equipped with an electric centrifugal pump installation is industrially applicable, has novelty, and is not obvious to a specialist of average qualification.

Claims (1)

A method for hydrodynamic research of a well equipped with an electric centrifugal pump installation, comprising transmitting information from the downhole device to the wellhead by means of an underground electric motor power cable for its intended use, characterized in that the downhole device is placed in a container hydraulically connected through openings with the downhole space and fixedly fixed conductive fastening elements on the basis of an electric centrifugal pump, while in a container with a deep a device is placed with a rib for feeding inhibitors of asphalt-resin-paraffin substances, and / or corrosion, and / or scaling, and / or emulsion formation into the well.

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