RU218123U1 - Submersible installation of a vane pump with a downhole separator of mechanical impurities - a gas phase enlarger - Google Patents

Abstract

The utility model relates to the oil industry and can be used in the extraction of oil from wells with a high content of free gas and abrasive particles by means of electric submersible pumps. The technical result of the utility model is to increase the reliability and efficiency of the installation of a vane pump with a downhole separator of mechanical impurities - a gas phase enlarger due to the separation of a part of free gas and mechanical impurities, abrasive particles before entering the pump, reducing energy consumption and cost. The claimed technical result is achieved due to the fact that in a submersible installation of a vane pump with a downhole mechanical impurities separator - a gas phase enlarger, containing a vane pump with inlets, a submersible motor, in the lower part of which a downhole mechanical impurities separator is installed - a gas phase enlarger, containing a housing the separator, the separator installed on it, the inlet to the separator of mechanical impurities is made below, and the outlet from the separator and the inlet to the vane pump are above the separator, a coupling that connects the separator housing and a cylindrical housing, inside which a hollow cylindrical pipe is installed coaxially with the formation of an annular channel, in the lower part of which a hollow screw is installed, a discharge channel formed by the inner diameters of the hollow screw and a hollow cylindrical pipe, a spiral channel formed between the screw blades and the inner diameter of the housing, a cylindrical vortex chamber attached to the lower part of the housing with a cone-shaped part at the bottom, to which a settler is attached to collect mechanical impurities, a cylindrical body and a branch pipe with a hollow screw are installed in the coupling, between the inner diameter of the coupling and the outer diameter of the hollow cylindrical branch pipe an annular channel is formed in the coupling, which is connected to the annular channel between the inner diameter of the cylindrical body and the outer diameter of the hollow cylindrical branch pipe, inlet the channels connecting the annular space with the annular channel of the coupling are made in the coupling in such a way that the distance between the inlet channels and the screw is no more than one screw diameter, the area of the flow part of the inlet channels is more than twenty percent larger than the area of the flow part of the screw channels, while the thickness of the hollow auger blades is from two to eight millimeters, the number of hollow auger blades is from one to five, the flow part of the separator, consisting of a coupling, a cylindrical body and a sump for collecting mechanical impurities, is hermetic, connected to the annulus only through inlet channels. 6 w.p. f-ly, 4 ill.

Description

The utility model relates to the oil industry and can be used in the extraction of oil from wells with a high content of free gas and abrasive particles by means of electric submersible pumps.

It is known from patent RU 114720 a device for cleaning well fluid, containing a cylindrical housing with inlets, a separating unit in the form of a hollow screw with a profiled spiral and a branch pipe for draining fluid, located in the lower part of the housing and attached to the lower part. body sump for collection of mechanical impurities. In the upper part of the vortex chamber, a conical bore is made, in which a profiled spiral of a hollow screw with a counter-conical outer surface is placed, and the outer surface of the shaped spiral has a spiral surface of contact with the surface of the conical bore, forming a spiral channel communicating the inlets with the cavity of the truncated cone of the vortex chamber , and the cross-sectional area of the spiral channel decreases towards its lower part.

The disadvantages of the known device for cleaning the fluid are low efficiency due to the fact that the solid particles at the outlet of the screw have a radial velocity component from the periphery to the center due to the fact that the spiral channel between the screw and the housing has a conical shape. For effective separation, the taper of the screw must be eliminated.

The closest analogue to the claimed design is a downhole gas-sand separator from patent RU 2529978, containing a cylindrical body with inlets, in the upper part of which a cylindrical pipe is installed concentrically, containing a separating unit in the form of a hollow screw with a profiled spiral, a spiral channel communicating the inlets with a cavity truncated cone, a vortex chamber in the form of a hollow truncated cone, concentrically mounted in the lower part of the housing under the branch pipe with a separating unit, and attached to the lower part of the housing a sump to collect mechanical impurities. The profiled spiral of the hollow screw is double-threaded, and the outer surface of the profiled double-threaded spiral has a spiral surface of contact with the inner cylindrical surface of the body, forming a two-threaded spiral channel connecting the inlets with the internal cavity of the body above the vortex chamber, while the profiled two-threaded spiral is located on the hollow screw below the inlet holes in the separator housing at a distance exceeding one outer diameter of the screw, and a sealing element is installed on the cylindrical housing above the inlet holes, blocking the annulus, while the geometric dimensions of the spiral channels and the vortex chamber are selected depending on the well flow rate and the flow rate of the well pump used.

The disadvantages of the closest analogue are low efficiency due to large hydraulic losses in the long channel between the inlets in the housing and the screw inlet, high cost due to the large length. Also, there is no pre-separation of solid particles in the inlet channel.

In a thin-walled pipe, it is difficult to make holes that direct the flow along the radius and (or) in a spiral into the screw screen.

The technical problem of the utility model is the creation of a downhole separator of mechanical impurities - a gas phase enlarger, during the operation of which hydraulic losses are reduced, preliminary separation is carried out.

EFFECT: reduced power and energy consumption when operating the unit with a lower content of free gas at the inlet.

The technical result of the utility model is to increase the reliability and efficiency of the installation of a vane pump with a downhole separator of mechanical impurities - a gas phase enlarger due to the separation of a part of free gas and mechanical impurities, abrasive particles before entering the pump, reducing energy consumption and cost.

The claimed technical result is achieved due to the fact that in a submersible installation of a vane pump with a downhole mechanical impurities separator - a gas phase enlarger containing a vane pump with inlets, a submersible motor, in the lower part of which a downhole mechanical impurities separator is installed - a gas phase enlarger containing a housing the separator, the separator installed on it, the inlet to the separator of mechanical impurities is made below, and the outlet from the separator and the inlet to the vane pump are above the separator, a coupling that connects the separator body and a cylindrical body, inside of which a hollow cylindrical pipe is installed coaxially with the formation of an annular channel , in the lower part of which a hollow screw is installed, a discharge channel formed by the inner diameters of the hollow screw and a hollow cylindrical pipe, a spiral channel formed between the screw blades and the inner diameter of the housing, a cylindrical vortex chamber with a cone-shaped part at the bottom attached to the lower part of the housing, to which it is attached a sump for collecting mechanical impurities, a cylindrical body and a pipe with a hollow screw are installed in the coupling, between the inner diameter of the coupling and the outer diameter of the hollow cylindrical pipe an annular channel is formed in the coupling, which is connected to the annular channel between the inner diameter of the cylindrical body and the outer diameter of the hollow cylindrical pipe, the inlet channels connecting the annular space with the annular channel of the coupling are made in the coupling in such a way that the distance between the inlet channels and the screw is no more than one screw diameter, the area of the flowing part of the inlet channels is more than twenty percent larger than the area of the flowing part of the screw channels, with In this case, the thickness of the hollow auger blades is from two to eight millimeters, the number of hollow auger blades is from one to five, the flow part of the separator, consisting of a coupling, a cylindrical body and a sump for collecting mechanical impurities, is hermetic, connected to the annulus only through inlet channels.

The input channels are directed at an angle to the horizon plane.

The inlet channels are directed at an angle to the plane of the horizon, or (and) to the plane passing through the axis of the coupling, directing the incoming flow in a spiral.

The blades of the hollow auger have a helical surface of variable stroke.

Protective centralizers are installed at the top and bottom of the separating element, preventing damage to the separating element when lowering and raising the separator.

A discharge auger is installed in the discharge channel.

A gravity separator is installed in front of the pump inlets.

The claimed technical result is explained as follows.

In a thick-walled coupling, in contrast to a thin-walled body, it is possible to make an inlet channel (channels) that directs the flow along the radius and (or) spiral due to this, preliminary separation is carried out, areas with an increased concentration of gas and mechanical impurities are formed. Discrete particles are combined, their diameter increases. Due to this, there is a more efficient separation of gas and mechanical impurities in the screw.

Due to the flow entering the screw blades with an optimal angle of attack, dispersion, mixing of liquid, gaseous and solid phases is eliminated or at least significantly reduced. These processes reduce the efficiency of phase separation and formation fluid purification from mechanical impurities. When the flow enters the screw blades with an optimal angle of attack, a more efficient phase separation occurs, the well fluid is supplied to the pump with a large average diameter of free gas bubbles. Therefore, the separation efficiency at the pump inlet increases, less free gas and mechanical impurities, abrasive particles, together with the well fluid, enter the pumping unit inlet, which leads to an increase in the efficiency and reliability of its operation.

The tightness of the flow part of the separator, consisting of a coupling, a housing and a container, is necessary in order to create a pressure drop at the inlet and outlet of the screw, which can reach several tens of meters. The pressure drop generates the tangential velocity and centrifugal acceleration necessary for separation. In the absence of tightness, for example, in a container, formation fluid will flow from the annulus and rise to the pump, reducing the flow rate and speed in the screw, and the separation efficiency.

The inlet channels to the separator are more difficult to make than the screw, their flow part is less perfect. To significantly reduce hydraulic losses, which depend on the speed squared, it is necessary to make the area of the flowing part of the inlet channels more than twenty percent larger than the area of the flowing part of the screw channels. The speed is determined by the ratio of the flow rate to the area. With an increase in the area of the channels, the hydraulic losses will decrease accordingly.

If the screw blades have a helical surface of variable stroke, this will make it possible to make the flow enter the screw with an optimal angle of attack in different flow regimes. Due to this, hydraulic losses and dispersion of the multiphase flow can be reduced.

The number of blades in the screw is determined by the flow rate, for lower flow rates it is preferable to choose screws with a smaller number of blades.

The thickness of the screw blades is determined based on the pressure drop and, accordingly, the velocity of the multiphase flow at the screw inlet. The pressure drop depends on the versatility of the separator. Separators for several feed ranges have large drops and, accordingly, inlet flow rates, and must have a large thickness of the screw blades.

Protective centralizers are installed above and below the separating, sealing element, which prevent damage to the separating, sealing element when lowering and raising the separator.

A discharge auger is installed at the inlet to the discharge channel, which provides additional rotation of the flow and enlargement of free gas bubbles when the well fluid moves upwards.

If in the design variant a gravity separator, for example, of a cup type, is installed in front of the pump inlets, then some of the bubbles previously enlarged in the separator-aggregator will pass by the entrance to the inlet module of the pump or gas separator. This will reduce the content of free gas and increase the efficiency and reliability of the installation.

After leaving the mechanical impurities separator, gas phase enlarger, the flow can enter the pump or gas separator installed at the pump inlet. At the same time, the larger the gas bubbles, the greater its amount will pass by the inlet to the pump or gas separator.

Figures 1-4 show:

Fig.1 - General view of the installation with a separator-aggregator;

Fig.2 - General view of the separator-enlarger;

figure 3 - coupling with channels;

Fig.4 - General view of the separator-enlarger with a discharge screw.

In figures 1-4 positions are indicated:

1. Submersible motor.

2. Vane pump.

3. Pump inlets.

4. Tubing.

5. Separator body.

6. Separator.

7. Centralizers.

8. Coupling.

9. Cylindrical separator body.

10. Hollow cylindrical nozzle.

11. Ring channel.

12. Desender input channel.

13. Annular channel in the coupling.

14. Hollow screw.

15. Spiral channel in the screw.

16. Vortex chamber.

17. Cone-shaped part of the vortex chamber.

18. Sump for mechanical impurities.

19. Removal auger.

20. Desender outlets.

21. Outlet channel.

22. Gravity separator.

The submersible installation of a vane pump with a downhole separator of mechanical impurities - a gas phase enlarger contains a submersible motor 1, a vane pump 2 with inlets 3, tubing 4.

In the lower part of the submersible motor 1, a downhole mechanical impurities separator is installed - a gas phase enlarger.

The separator contains a separator body 5, a separator 6 installed on it, so that the inlet channel or inlet channels 12 to the separator of mechanical impurities are installed below, and the outlet holes 20 from the separator and the inlet holes 3 to the vane pump 2 are above the separator 6.

The coupling 8 connects the separator body 6 and the cylindrical body 9, inside which a hollow cylindrical pipe 10 is installed coaxially, with the formation of an annular channel 11, in the lower part of which a hollow screw 14 is installed.

The discharge channel 21 is formed by the inner diameters of the hollow screw 14 and the hollow cylindrical pipe 10.

The spiral channel 15 is formed between the blades of the hollow screw 14 and the inner diameter of the cylindrical body 9.

The thickness of the blades of the hollow screw 14 is from two to eight millimeters. If the thickness is less, then the probability of hydroabrasive cutting of the inlet sections of the blades increases, with a subsequent deterioration in the separation efficiency. If the thickness is greater, then the radius of the spiral increases, respectively, the centrifugal force and the separation efficiency decrease noticeably. The number of blades of the hollow auger is 14 - from one to five. One blade in the auger is recommended for low flow rates, as the flow rate increases, the number of blades increases. If the number is more than five, there is a decrease in the area of the flow path, since it is impossible to reduce the thickness of the blades below a certain value. Since the diametral dimension of wells for the production of reservoir fluid is limited, the above area reduction leads to degradation of the flow part of the screw channels and a decrease in separation efficiency.

The blades of the hollow screw 14 have a helical surface of variable stroke.

A cylindrical vortex chamber 16 with a cone-shaped part 17 at the bottom is attached to the lower part of the cylindrical body 9, to which a sump 18 is attached to collect mechanical impurities.

The cylindrical body 9 and the hollow cylindrical pipe 10 with the hollow screw 14 are installed in the coupling 8.

Between the inner diameter of the sleeve 8 and the outer diameter of the hollow cylindrical pipe 10, an annular channel is formed in the clutch 13, which is connected to the annular channel 11 between the inner diameter of the cylindrical body 9 and the outer diameter of the hollow cylindrical pipe 10.

The inlet channel (channels) 12, made in the sleeve 8, connects the annulus with the annular channel in the sleeve 13 and directs the incoming flow in a spiral.

The coupling 8 has an inlet channel 12 connecting the annular space with the annular channel 13 of the coupling 8, the axis of which is directed at an angle to the horizon plane, and to the plane passing through the axis of the coupling 8, directing the incoming flow in a spiral.

The inlet channels 12 connecting the annular space with the annular channel 13 of the coupling are made in the coupling 8 in such a way that the distance between the inlet channels and the screw is no more than one screw diameter. The multiphase flow is supplied to the separator along an arcuate trajectory, due to which preliminary separation is carried out before entering the screw, the inlet channels connecting the annular space with the annular channel of the coupling are made in the coupling so that the distance between the inlet channels and the screw is no more than one screw diameter. At a greater distance, due to dispersion, mixing, the effect of preliminary separation is reduced, hydraulic losses also increase, which are proportional to the length of the channel, and the cost of the product increases.

The area of the flowing part of the inlet channels 12 is more than twenty percent larger than the area of the flowing part of the spiral channels 15 of the hollow screw 14.

In the design version, an additional separator can be installed, while both separators must have a cup-like shape and be installed with concave parts facing each other.

Protective centralizers 7 are installed on top and bottom of the separator 6, which prevent damage to the sealing separating element when lowering and raising the separator.

In a design variant, a discharge auger 19 can be installed at the inlet to the discharge channel 21.

In a design variant, a gravity separator 22, for example, of a cup type, can be installed at the inlet to the inlet holes 3 of the vane pump 2.

The submersible installation of a vane pump with a downhole mechanical impurities separator - a gas phase enlarger works as follows.

Formation fluid with mechanical impurities enters the annular channel 11 through the inlet channel(s) 12. The inlet channel 12 directs the formation fluid flow along the radius. Due to the centrifugal force, mechanical (abrasive) particles are separated, which are collected at the periphery of the annular channel 11, and free gas bubbles, which are collected and enlarged in the center. Due to the pre-swirling, a preliminary separation of solid and gaseous particles occurs.

At the outlet of the hollow screw 14 in the vortex chamber 16 is the end of the separation. Solid particles due to centrifugal forces are collected at the periphery of the vortex chamber 16. Solid particles are displaced down to the cone-shaped part of the chamber 17 and then settle in the sump 18. The gas-liquid mixture purified from mechanical impurities enters the hollow cylindrical pipe 10 and then moves up. After passing through the discharge auger 19, the flow receives additional rotation, and the bubbles of the gas phase are enlarged. The gas-liquid mixture with large gas bubbles at the inlet to the vane pump 2 moves from top to bottom, passing through the gravity separator 22, installed in front of the inlets of the pump 3. At the same time, the gas bubbles enlarged in the separator move upward past the pump.

Claims (7)

1. Submersible installation of a vane pump with a downhole mechanical impurities separator - a gas phase enlarger, containing a vane pump with inlets, a submersible motor, in the lower part of which a downhole mechanical impurities separator is installed - a gas phase enlarger, containing a separator body, a separator installed on it, an inlet into the separator of mechanical impurities is made below, and the outlet from the separator and the inlet to the vane pump is above the separator, a coupling that connects the separator body and a cylindrical body, inside of which a hollow cylindrical pipe is installed coaxially with the formation of an annular channel, in the lower part of which a hollow screw is installed, a discharge channel formed by the inner diameters of the hollow screw and a hollow cylindrical pipe, a spiral channel formed between the screw blades and the inner diameter of the housing, a cylindrical vortex chamber attached to the lower part of the housing with a cone-shaped part at the bottom, to which a sump is attached to collect mechanical impurities, characterized in that that the cylindrical body and the branch pipe with a hollow screw are installed in the sleeve, between the inner diameter of the sleeve and the outer diameter of the hollow cylindrical branch pipe an annular channel is formed in the sleeve, which is connected to the annular channel between the inner diameter of the cylindrical body and the outer diameter of the hollow cylindrical branch pipe, the inlet channels connecting the annulus space with an annular channel of the coupling, made in the coupling in such a way that the distance between the inlet channels and the screw is no more than one diameter of the screw, the area of the flowing part of the inlet channels is more than twenty percent larger than the area of the flowing part of the screw channels, while the thickness of the blades of the hollow screw is from two to eight millimeters, the number of blades of the hollow screw is from one to five, the flow part of the separator, consisting of a coupling, a cylindrical body and a sump for collecting mechanical impurities, is hermetic, connected to the annulus only through inlet channels. 2. Submersible installation of a vane pump according to claim 1, characterized in that the inlet channels are directed at an angle to the horizon plane. 3. Submersible installation of a vane pump according to claim 1, characterized in that the inlet channels are directed at an angle to the plane of the horizon and/or to the plane passing through the axis of the coupling, directing the incoming flow in a spiral. 4. Submersible installation of a vane pump according to claim 1, characterized in that the blades of the hollow screw have a helical surface of variable stroke. 5. Submersible installation of a vane pump according to claim 1, characterized in that protective centralizers are installed above and below the separating element, preventing damage to the separating element when lowering and raising the separator. 6. Submersible installation of a vane pump according to claim 1, characterized in that a discharge screw is installed in the discharge channel. 7. Submersible installation of a vane pump according to claim 1, characterized in that a gravity separator is installed in front of the pump inlets.

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