RU2178518C2 - Device for wave treatment of formation - Google Patents

Abstract

FIELD: oil and gas producing industry; devices for formation stimulation by elastic vibrations. SUBSTANCE: device has barrel with central hole inlet channels and nozzle connected with inlet channel, central wedge-shaped dissector. Device has control channels, each channel is connected with one discharge chamber. Control chambers are located perpendicular to nozzle and connected with it. Inlets of working channels are connected with nozzles. Jet ejector is installed coaxially under central wedge-shaped dissector and made with isolated injection channels. Electrohydraulic members serve for creation of disturbance pressure in discharge chambers during discharges. Jet ejector is connected with outlet of working channel and forms circular cylindrical channel with its external walls together with internal surface of barrel in its lower part. Chamber inlet is connected with outlet of working channel and chamber outlet is connected with injection channels of jet ejector. Nozzle is separated by central wedge-shaped dissector. Central sectors may be interconnected. Device may have round hollow vessels located perpendicular to nozzle. EFFECT: higher efficiency of formation treatment due to possible selection of working frequency of generated vibrations, increased reliability, radiation power and production of pulses of any shape. 3 cl, 6 dwg

Description

 The invention relates to the oil industry and is intended to impact on the reservoir by elastic vibrations.

 Known hydrodynamic pulsator (US Pat. N 2054532), containing a hollow body with input channels, a camera with a double-acting working body installed in it with the possibility of overlapping input channels. The working body is made in the form of a washer, alternately blocking the inlet channels, allowing pressure fluctuations to be excited in the formation zone.

 A disadvantage of the known solution is the low efficiency of the impact on the reservoir due to small oscillation amplitudes, large pressure losses at the inlet of the device, significant wear of the working surfaces of the device. The excited oscillation frequency is in a narrow range of kilohertz frequencies and is unstable due to cavitation wear of the device channels. There is no way to control the frequency of the generated oscillations. The presence of moving parts leads to a loss of energy for mechanical work, to a decrease in the reliability and service life of the device.

 The closest in technical essence to the present invention is a low-frequency hydraulic spool type vibrator (Gadiev S. M. Use of vibration in oil production. Nedra, 1977, p. 49-51). This vibrator includes a barrel rigidly fixed in the housing with slit-like slots on the generatrix. On the trunk, a spool freely rotates, having slots along the generatrix. Rotating as the fluid flows, the spool closes the slots in the barrel, resulting in intense water hammering.

 The disadvantages of the known vibrator include a decrease in the effectiveness of the impact on the reservoir due to the fact that the rotation speed of the spool depends on the flow rate, while the presence of a large starting torque makes it impossible to create oscillations at low frequencies. The amplitude of the arising oscillations becomes significant only in a narrow frequency range from 150 to 200 Hz, while the device uses a significant flow rate of the working fluid, about 15 - 20 dm / s.

 The presence of moving parts leads to a loss of energy for mechanical work, to a decrease in the reliability and service life of the device (the service life of the vibrator 3-4 processing for 15 to 20 hours).

 The objective of the invention is to increase the efficiency of formation processing due to the possibility of choosing the operating frequency of the generation of oscillations, increasing the reliability, power of radiation and obtaining any pulse shape.

 This task is achieved by the fact that in the device for wave processing of the formation, containing the barrel with a Central input channel and a nozzle connected to the input channel, contain control channels, each of which is connected to the output of one of the discharge chambers, located perpendicular to the nozzle and connected to it, working channels, the inputs of which are connected to the nozzle, a central wedge-shaped divider, a jet ejector mounted coaxially under the central wedge-shaped divider and made with insulated injection channels, discharge chambers and electro-hydraulic elements to create a pressure perturbation in the discharge chambers during discharges, while the jet ejector is connected to the outlet of one of the working channels and forms an annular cylindrical chamber connected to the outlet by its outer walls with the inner surface of the muffled barrel in its lower part the second working channel and the output connected to the injection channels of the jet ejector, and the nozzle is divided by a central wedge-shaped divider.

 The control channels of the device can be communicated with each other.

 The device may have two rounded hollow containers located perpendicular to the nozzle.

 A positive effect in the device is achieved by the fact that, using the electronic switching unit of the injection pump, favorable conditions are created for the efficient switching of the flow from the open channel to the muffled working channel, injection of liquid from it, and pressure reduction in it, and thanks to the use of isolated injection channels, high fluid injection.

 Injection of liquid occurs in the phase of the flow of the jet through an open channel. This allows the use of a muffled channel where a water hammer is generated as a pressure booster. The nature of the generated oscillations is similar to the pulsations that occur in a low-frequency hydraulic spool type vibrator. In one phase, a hydraulic shock is observed with a sharp increase in pressure, in the other phase, intense flow pulsation. The possibility of controlling a powerful high-energy jet by means of pressure disturbances created by discharges of electro-hydraulic elements controlled by a computer is realized. The bandwidth of the bistable switch operating on the Coanda effect reaches 1 000 000 Hz and this allows you to adjust the frequency of the device from 0.001 to 1 000 000 Hz from the computer to the wellhead or at the bottom and to receive oscillations from harmonic to substantially non-linear and soliton.

When you perform the switching node of the jet ejector (version 2) in the form of control channels located perpendicular to the nozzle that are interconnected (Fig. 4.), the self-oscillating mode
T = C / (2 • l),
T is the oscillation period, C is a constant, l is the length of the chamber.

W - период колебаний, h - высота емкости.When performing the switching unit for the operation of the jet ejector (version 3) in the form of rounded hollow containers perpendicular to the nozzle (Fig. 5), the generator mode is implemented, which allows you to change the oscillation frequency by changing the flow rate

W is the period of oscillations, h is the height of the tank.

 where V is the velocity of the outflow from the nozzle.

Feedback is provided by internal communication channels
W = C / (4 • l),
where L is the length of the chamber.

 In FIG. 1 shows a device, a section; in FIG. 2 is a section AA in FIG. 1; in FIG. 3 - section BB in FIG. 1; in FIG. 4 is a section BB of FIG. 1; in FIG. 5 - switching unit - jets, in FIG. 6 - switching unit - jets.

 The device for wave treatment of the formation includes a barrel 1 with a central inlet channel 2 for supplying injected fluid under pressure, in the outlet of which there is a nozzle 3, which are directed perpendicular to the control channels 4, 5, connected to the discharge chambers 6, 7. Two workers depart from the nozzle channel 8, 9, separated by a wedge-shaped divider 10. The output of the working channel 9 is communicated with an annular cylindrical chamber damped in the barrel 17. The output of the working channel 8 is communicated with a jet ejector 11 located coaxially under the wedge a spherical divider 10, with an output channel 12. The jet ejector 11 comprises a cylindrical inlet nozzle 13, a mixing chamber 15, and a diffuser 16. On the side surface of the ejector, there are insulated ejection channels 14 communicating with the muffled chamber.

 The device operates as follows.

 When a liquid is supplied under pressure into the channel 2 of barrel 1, it enters the nozzle 3 and, due to the Coanda effect, adheres either to the wall of the channel 8 or to the wall of the channel 9, depending on the always existing pressure difference in the control channels 4, 5. When a discharge occurs in Chamber 7 increases the pressure in the chamber 7, and then in the control channel 4, which leads to a quick transfer to the wall of the channel 8, where it again stably adheres. When a discharge appears in chamber 6, pressure increases in chamber 6, and then in control channel 5, which leads to a rapid transfer to the wall of channel 9, where it again adheres steadily.

 In the phase of flowing through the channel 8, the liquid enters the jet ejector 11. In this phase of the operation of the device, the liquid is pumped out from the chamber 17 through the channels 14, as a result of which the pressure in the chamber 17 decreases. In the phase flowing through the channel 9, the liquid enters the muffled chamber 17. In the phase of the jet flowing through the channel 8, a pulsation of the liquid flow through the output channel 12 of the diffuser of the jet ejector occurs. In the phase of the jet flowing through channel 9, a powerful hydraulic shock is created when liquid enters the muffled chamber 17 with reduced pressure.

 The device for wave processing of the formation with electric control allows to obtain high efficiency of processing the formation, the ability to create high-amplitude oscillations of high power and any pulse shape in a wide frequency range, since there is no influence of flow fluctuations, reduced energy costs due to the absence of losses on mechanical work , the ability to quickly tune the device to the optimal frequency in accordance with the geological and physical conditions of the object, increasing the reliability of the device Twa due to lack of mechanical parts, improve efficiency.

Claims (3)

 1. A device for wave processing of the formation, containing a barrel with a Central input channel and a nozzle connected to the input channel, characterized in that it contains control channels, each of which is connected to the output of one of the discharge chambers located perpendicular to the nozzle and connected to it, working channels, the inputs of which are connected to the nozzle, a central wedge-shaped divider, a jet ejector mounted coaxially under the central wedge-shaped divider and made with insulated injection channels, discharge nuclear chambers and electro-hydraulic elements to create a pressure perturbation in the discharge chambers during discharges, while the jet ejector is connected to the outlet of one of the working channels and forms an annular cylindrical chamber connected to the output of the second working chamber with its outer walls with the inner surface of the muffled barrel in its lower part the channel and the output connected to the injection channels of the jet ejector, and the nozzle is divided by a central wedge-shaped divider.  2. The device according to claim 1, characterized in that the control channels are interconnected.  3. The device according to p. 1, characterized in that it has two rounded hollow containers located perpendicular to the nozzle.

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