RU131503U1 - DEVICE FOR GENERATING ELASTIC PULSES IN A HYDROSPHERE OF A HORIZONTAL WELL - Google Patents

Abstract

1. A device for generating elastic impulses in the hydrosphere of a horizontal well, consisting of a ground-based power supply, control and control unit and a downhole tool housing, in which are located: an increased voltage source in the form of series-connected transformers, a rectification unit and a voltage multiplication unit, a capacitor storage of electrical energy , a spark gap and a radiator, consisting of high-voltage and low-voltage electrodes, characterized in that the radiator is equipped with a low-voltage electrode, a connection with a rotating body block made in the form of a cylinder mounted on slide bearings with a cutout for contact with the well fluid, filled on the opposite side of the cut with heavy metal, for example, lead, so that when moving in a horizontal well, the cut is always directed upward. 2. The device according to claim 1, characterized in that the ground-based power, control and control panel is connected to the downhole tool with a rigid geophysical cable or coiled tubing, on which the equipment is delivered to the well. The device according to claim 1, characterized in that the body of the downhole tool is equipped with centralizers. The device according to claim 1, characterized in that the body of the downhole tool is equipped with elastic packers. The device according to claim 1, characterized in that the arrester is made in the form of a non-flammable thyratron.

Description

The utility model relates to the field of mining, in particular, to the means of influencing the bottom-hole zone of horizontal oil-filled oil wells by generating directional elastic impulses based on plasma-pulse impact.

The prior art electro-hydraulic downhole device containing an electric energy storage device, a trigger device-discharger with electrodes (Pat. RF No. 2283951, prior. 02.10.2005, publ. 09.09.2006, Е21 В 43/25).

The disadvantage of this device is its inability to work in horizontal wells, in particular the complexity of the delivery of equipment to the horizontal part of the well.

A well-known source of seismic energy containing a plasma-pulse discharger, a storage energy unit, a charger, a control system, a wire feed mechanism for closing the electrodes, the specified source is made of two sections, the first section contains a plasma-pulse spark gap, a feed mechanism calibrated conductor and power storage unit, and the second section contains a control system and a charger. According to a second embodiment, said source may have a diameter of 42 mm and a length of 3750 mm. According to the third embodiment, the specified source is equipped with a means for lowering and lifting it, the wellhead gateway used (Pat. RF No. 105476, prior. 05.03.2011, publ. 10.06.2011, G01V 1/00).

The disadvantage of this design is the low reliability of the used discharge device. The design of the emitter of this equipment does not provide for work in horizontal wells.

As the closest analogue, the well-known borehole source of seismic energy was selected to affect the bottom-hole zone of the well and oil-saturated formations, containing a casing, a high-voltage electrode, a low-voltage electrode, an electric discharge source, a metal wire feed mechanism (Pat.RF No. 2373386, G01V 1/157, prior. 07/01/2008, published on 11/20/2009).

A disadvantage of the known design is that in order to initiate a discharge, it is necessary to close the interelectrode space with a calibrated conductor, which in the conditions of a horizontal well will be extremely difficult due to clogging of the space between the electrodes, especially in horizontal wells with uncased horizontal sections. Also, this design does not provide devices for centering the device, which will complicate the delivery of equipment to a horizontal section of the well. A known source does not allow to focus and direct the elastic impulse.

The technical result of the utility model is to simplify the design, increase reliability and ease of use, reduce labor costs.

The technical result is achieved by the fact that the device for generating elastic impulses in the hydrosphere of a horizontal well, consisting of a ground-based power supply, control and control unit and a body of a downhole tool, in which are located: an increased voltage source in the form of series-connected transformers, a rectification unit and a voltage multiplier, capacitor storage of electrical energy, a spark gap and a radiator consisting of high-voltage and low-voltage electrodes, equipped with a low-voltage electrode a radiator connected to a rotating block of the body, made in the form of a cylinder mounted on slide bearings with a cutout for contact with the well fluid, filled on the opposite side of the cut with heavy metal, such as lead, so that when moving in a horizontal well, the cut is always directed upward and the ground console power supply, control and monitoring is connected to the downhole tool with a hard geophysical cable or coiled tubing, on which the equipment is delivered to the well, while the well body of the device is equipped with centralizers, and in favorable conditions, instead of centralizers, elastic packers can be used to focus the elastic pulse into the treated zone, while the spark gap is made in the form of a non-flammable thyratron.

The inventive device comprises a ground power supply, control and monitoring unit 1 connected by a rigid geophysical cable 2 to a downhole tool (Fig. 1), in which are located: a high voltage multiplier 4, a capacitor storage of electrical energy 5, an electric discharger 6, a high voltage emitter electrode 7, low voltage emitter electrode 8. Pos. 9 is a diagram for controlling the discharge of electric energy storage and a calibrated conductor feed mechanism.

In the casing of the downhole tool 3 on the chassis there are capacitors 10 of the energy storage 5 with equalizing additional wire resistors 11 of different lengths (figure 2). To center the equipment and simplify the process of delivering the source to the horizontal section of the well, centralizers 12 are used. To increase the reliability and increase the durability of the device, the arrester 6 is made in the form of a non-burnt thyratron (Fig. 4). The device has a rotating housing unit 13, the base of which is filled with heavy metal 14, for example, lead.

The device operates as follows.

During tripping operations on the well, the ground power, control and monitoring unit 1 is connected using a rigid geophysical cable 2 with the downhole tool and the device is checked in manual mode. By pressing the “charge” button a voltage of 300 ÷ 1000 Hz is applied to charge the capacitors. The process of voltage growth and the achieved charge voltage is recorded by the control and measuring equipment in the ground control and monitoring power supply unit 1. By pressing the "discharge" button, the capacitors 10 of the electric energy storage device 5 are discharged, and the zero voltage is recorded. Then it checks the operation of the device in automatic mode by switching the toggle switch "type of work" to "automatic mode".

To prepare the well for work, it is necessary to remove the submersible pump from the well and install the block balance of the logging elevator at the wellhead. After that, the descent of the downhole tool on a rigid geophysical cable 2 into the well begins with the depth control of the depth gauge in the horizontal part of the well.

The formation is processed at stops at 0.5-1.0 m along the length of the wellbore when the downhole tool moves from the bottom to the mouth for 10-30 pulses with a repetition period of 2 pulses per minute throughout the horizontal section of the well.

After lifting and removing the downhole tool from the well, the submersible pump descends again and the work of the well is restored.

Processing efficiency is evaluated by indicators before and after processing.

The use of devices for generating elastic pulses with energy of the order of 1.0-1.2 kilojoules and a frequency spectrum of 300-1000 Hz in horizontal oil wells allows decolmatization of the borehole zone and, by acting on the reservoir, to excite resonance oscillations in the well-reservoir system , contributing to the restoration and increase in permeability (piezoconductivity) of the reservoir.

The range of plasma-pulse exposure is 300-400 m, so all wells located in this radius will respond positively.

The proposed utility model solves the technical problem of creating an effective means for initiating elastic impulses in horizontal oil wells of significant power with a wide frequency range and creating impulses of compression and discharge pressure, cleaning the borehole zone of production and injection wells and creating their own parametric resonance of the "well - reservoir" system , restoring and increasing the initial permeability of the formation, increasing the mobility of the reactive agent and increasing hydrodynamic connection between the well and the formation.

Currently, deviated and horizontal wells are increasingly used in the development of oil and gas wells. Geophysical work in such wells is difficult, since the delivery of geophysical instruments in the study interval is a difficult technical task. In this regard, it is planned to deliver the downhole tool of the source of elastic impulses to the horizontal section of the well through the use of a rigid geophysical cable 2. Cables of this design are guaranteed to pass a horizontal section (92 °) up to 300 meters long and an inclined direction (75 °) up to 800 length meters. The facilitation of the process of delivering equipment to the horizontal part of the well is also facilitated by the presence of additional centralizers 12 at the device, which greatly simplifies its advancement in highly curved intervals of the well (Fig. 2). In the absence of sludge in the horizontal section of the well, as well as when the content of mechanical impurities in the produced product is not more than 0.2 g / l, the use of elastic packers is provided, which allows for more focused processing.

In the proposed utility model, a spark-free thyratron is used as a spark gap 6 (Fig. 4). The main advantages of a non-flammable thyratron are its high profitability, simplicity of design, small dimensions and weight, the ability to transmit large currents in a pulsed mode, the stability of established parameters, durability, high vibration resistance, a large operating temperature range and small starting currents with a large input resistance, which in combination allows to increase the reliability and durability of downhole equipment.

Processing of the borehole zone of horizontal wells with various technologies that improve the hydrodynamic connection between the well and the formation, the direction of influence that cannot be controlled, for example, hydraulic fracturing of the formation, is fraught with a sharp watering of the production of the well due to the creation of highly permeable cracks in the part of the formation located below the trajectory of the horizontal section, where, as a rule water-oil contact is located. The elimination of the consequences of such treatments is expensive and its effectiveness in various Under different conditions, which makes it difficult to restore. The inventive utility model allows you to process horizontal wells with minimal risk of water breakthrough to the well due to the use of a rotating block of the casing 13 of a special form (figure 2). The lower part of the rotating body is filled with heavy metal 14, for example, lead, in order to shield the elastic impulse, to prevent its propagation to the lower zone of the formation and to focus on the zone of the formation located above the trajectory of the horizontal section of the well (Fig. 4). Thus, the elastic wave propagates in the vertical direction, creating microcracks in the near-wellbore zone of the formation and improving the hydrodynamic connection of the well with the oil-saturated part of the formation.

Claims (5)

1. A device for generating elastic impulses in the hydrosphere of a horizontal well, consisting of a ground-based power supply, control and control unit and a downhole tool housing, in which are located: an increased voltage source in the form of series-connected transformers, a rectification unit and a voltage multiplication unit, a capacitor storage of electrical energy , a spark gap and a radiator, consisting of high-voltage and low-voltage electrodes, characterized in that the radiator is equipped with a low-voltage electrode, a connection with a rotating body block made in the form of a cylinder mounted on sliding bearings with a cutout for contact with the well fluid, filled on the opposite side of the cut with heavy metal, for example, lead, so that when moving in a horizontal well, the cut is always directed upward. 2. The device according to claim 1, characterized in that the ground-based power, control and control panel is connected to the downhole tool with a rigid geophysical cable or coiled tubing, on which the equipment is delivered to the well. 3. The device according to claim 1, characterized in that the body of the downhole tool is equipped with centralizers. 4. The device according to claim 1, characterized in that the body of the downhole tool is equipped with elastic packers. 5. The device according to claim 1, characterized in that the arrester is made in the form of an incandescent thyratron.

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