CN104653155A - A device and system for exploratory well electric pump oil testing and production testing - Google Patents

Abstract

The invention provides a liquid drainage device and system for exploration well electric pump oil testing, production testing, and belongs to the technical field of drilling well testing, production testing, and liquid drainage. The device includes a pump head, a centrifugal pump, a separator, a submersible motor, a tester, and a slotted screen that are connected sequentially through oil pipes from top to bottom. The outer shroud. The liquid drainage device and system provided by the present invention can meet the technical requirements of large volume fracturing for rapid liquid drainage in exploratory wells, and can work in an environment without power supply in the field. It is easy to move, simple in construction procedures, and low in noise. Smaller; at the same time, the drainage speed is improved, the oil test and production cycle is shortened, the ground device is easy to move, the overall technical construction operation is simple, pollution-free, and the risk of well control is small. A set of devices can complete multiple constructions, and the equivalent cost is low , the implementation of the technical solution provided by the invention can greatly improve the economic benefits of the exploration area.

Description

A device and system for exploratory well electric pump oil testing and production testing

technical field

The invention relates to a liquid drainage device and system for exploration well electric pump oil testing and production testing, and belongs to the technical field of exploration well oil testing and production testing liquid drainage.

Background technique

Exploratory well testing and production testing is a necessary link in the process of oil and gas exploration and development. By discharging a certain amount of wellbore liquid, the properties and production of the oil produced liquid are analyzed, and finally the reserves of the entire exploration area are evaluated. Liquid drainage restricts the efficiency of oil testing, and is also the process with the largest workload in the process of oil testing and production. At the same time, through the process of liquid drainage, it is possible to have an accurate understanding of the reservoir and obtain more reliable oil testing conclusions. Therefore, high-quality fluid drainage can not only increase the speed of oil testing and shorten the oil testing period, but also obtain real reservoir data, thereby obtaining higher overall economic benefits in the oilfield exploration area.

As the conditions of exploration wells become more and more complex during the production of oil and gas fields, the technology of oil testing and production testing of exploration wells is also constantly developing. In recent years, the proportion of non-spontaneous wells and non-spontaneous formations in the expanding field has been increasing, and their main characteristics are three lows: low permeability, low pressure, and low porosity. These characteristics have led to an increase in the workload of oil testing and fluid drainage year by year. For such exploration wells, fracturing operations are generally required to improve the productivity of oil wells by fracturing reservoirs, especially the large volume fracturing wells that have emerged in recent years. The fracturing technology is applied more and more in exploration well reservoir stimulation. Exploration wells that implement large-scale volume fracturing generally require a huge amount of economic investment. During the fracturing process, the fracturing fluid squeezed into the formation is often tens of thousands of square meters. The speed of flowback is slow by relying on natural blowout, and a large amount of fracturing fluid cannot be returned in time. Drainage not only delays the progress of production, but also causes some damage to the reservoir. New requirements are put forward for the technology of drainage during the stage of oil test and production test.

At present, the existing technologies in the field of exploratory well testing and drainage mainly include: (1) Lifting and drainage method; this method is the earliest method used when the petroleum industry just started, and the process is complicated, so it is rarely used at present. (2) Swabbing and draining process: In the current onshore oilfield oil testing and draining methods, this method is the most widely used swabbing and draining technology, but the draining speed is extremely slow. (3) Gas lift drainage process; this process has a faster drainage speed, but requires ground nitrogen injection equipment to inject gas from the annular space, and the cost of gas injection is high, so it is not suitable for a long time drainage. (4) Liquid nitrogen drainage technology; the construction cost is high, and it has certain damage effects on the formation: one is back pressure damage, the other is low temperature damage, and the third is agitation damage; at the same time, it is easy to cause environmental pollution; (5) Coiled tubing Nitrogen drainage technology; its principle is similar to gas lift, but the equipment is heavy and the mobility is poor, it is not suitable for remote exploration wells, and the construction cost is high. (6) Ground-driven single screw pump drainage technology; this technology has many procedures and takes a long time for preliminary preparation; it has high requirements for the wear resistance of the pump body; the drainage cycle is long and the efficiency is low; the input cost is high; the failure rate is low High; the temperature resistance of the pump body is poor; (7) Hydraulic pump drainage technology, this technology mixes the power fluid and the produced fluid, making it more difficult to obtain the original properties of the formation fluid.

Therefore, it can be seen from the above-mentioned status quo that the commonly used liquid drainage technologies for exploratory wells have certain limitations and cannot meet the needs of oil testing and production testing for exploratory wells with large volume pressures in recent years.

Contents of the invention

In order to solve the problem that the existing exploratory well drainage technology cannot meet the needs of oil testing and production testing of exploratory wells with large volume pressures, the present invention further proposes an exploratory well electric pump oil testing and production liquid drainage device and system, which specifically includes The following technical solutions:

A well exploration electric pump oil testing and liquid drainage device, the lower end of the device is set in the oil layer at the lower part of the wellhead of the electric pump, and the device includes a pump head, a centrifugal pump, a separator, A submersible motor, a tester and a slotted screen pipe, the device also includes a shroud wrapping the separator, the submersible motor and the tester.

The liquid discharge device for oil testing and production testing of electric pump for exploratory wells according to the present invention also includes a check valve arranged above the pump head to prevent the fluid in the oil pipe from flowing back when the pump is stopped.

The liquid drainage device for oil testing and production testing of electric pump for exploration wells according to the present invention also includes a drainer arranged above the check valve, which can release the fluid in the oil pipe into the annular space of the oil casing during the pump inspection operation.

The drainage device of the electric pump for exploratory wells according to the present invention also includes a centralizer fixedly connected to the lower end of the slotted screen pipe, which forms a centralizing effect on the device and avoids obstruction during operation and wear of the device.

The oil testing and production drainage device of the exploration well electric pump according to the present invention also includes a protector arranged between the separator and the submersible motor, which is used to replenish oil for the submersible motor, isolate the well fluid at the same time, and avoid burning the pump. .

A well exploration electric pump oil test production test liquid drainage system, the system includes the above-mentioned exploration well electric pump oil test production test liquid drainage device and a ground control device, the ground control device includes a generator connected in sequence through wires, Transformer, frequency conversion control cabinet and junction box, the signal output end of the junction box is connected with the signal input end of the submersible motor through the surface cable and the downhole cable.

The ground control device of the present invention is arranged in a control room, and the control room includes a skid-mounted base so as to be moved or fixedly arranged.

The walls on both sides of the control room of the present invention are respectively provided with sound-absorbing air inlet slots and sound-absorbing air outlet slots.

The control room of the present invention is provided with a flue and a flue muffler, the lower exhaust port of the flue communicates with the generator, the upper exhaust port of the flue communicates with the outside through the roof of the control room, and the flue is silenced The device is set on the upper exhaust port of the flue.

An isolation foundation is arranged between the floor of the control room of the present invention and the generator.

In summary, the present invention uses the electric pump unit as the downhole fluid drainage lifting device of the exploration well, and the displacement of the electric pump drainage is significantly higher than that of the conventional exploration well drainage method, which solves the problem of slow fluid drainage after large volume fracturing of the exploration well. Problem; at the same time, the present invention also includes a deflector device, which changes the flow channel of the liquid into the pump, and the lower part of the deflector is connected to the screen, which can play a role in sand prevention. For wells with a tendency to scale, the deflector and the screen A metal anti-scaling device can also be added between the pipes to achieve the purpose of anti-scaling, so that the tester can easily measure the parameters of the downhole working conditions. Production pipe string; In addition, the ground device provided by the present invention is a set of multi-functional control room, which integrates functions such as power generation, power transformation, and control. By reading the downhole test data on the ground, it is possible to have an accurate understanding of the reservoir, A more reliable oil test conclusion is obtained. After the oil test and production test are completed, the control room can be easily moved to the next construction exploration well, which fully meets the technical needs of the exploration well drainage.

Description of drawings

Fig. 1 is the structural schematic diagram of the liquid drainage device for oil testing and production testing of exploration well electric pump provided by this specific embodiment;

Fig. 2 is a schematic structural diagram of the ground control device provided in this specific embodiment;

Fig. 3 is a schematic structural diagram of the electric pump test oil drainage system for exploration wells provided in this specific embodiment.

Detailed ways

This specific embodiment is a clear and complete description of the technical solutions of the present invention, and the embodiments therein are only some of the embodiments of the present invention, but not all of them. Based on the embodiments of the present invention, all other implementation manners obtained by those skilled in the art without creative efforts belong to the protection scope of the present invention.

This specific embodiment provides a kind of exploratory well electric pump oil test oil test production drainage device, as shown in Figure 1, the lower end of the device is arranged in the oil layer 29 at the bottom of the electric pump wellhead 14, and the device includes a top-to-bottom The pump head 18, the centrifugal pump 19, the separator 20, the submersible motor 22, the tester 23 and the slotted screen pipe 27 connected successively through the oil pipe 24, the device also includes the separator 20, the submersible motor 22 and the tester. The shroud 26 on the outside of the meter 23.

Specifically, the pump head 18 is used to connect the oil pipe 24 and the centrifugal pump 19. The function of the centrifugal pump 19 is to increase the downhole fluid pressure head and form a certain lift to lift the fluid to the ground; the function of the separator 20 is to complete gas-liquid separation. , to discharge the gas to the oil casing annulus; the function of the submersible motor 22 is to convert electrical energy into mechanical energy, and drive the separator 20 and the centrifugal pump 19 to rotate; the function of the tester 23 is to test parameters such as downhole temperature, pressure, vibration intensity, etc. And the parameter data is transmitted to the ground; the role of the slotted screen 27 is to prevent sand and prevent downhole sundries from entering the pump. The role of the shroud 26 is to change the passage of the well fluid into the pump. During the lifting process of the conventional electric pump, the well fluid directly enters the oil-gas separator. Pass through the slotted screen pipe 27, and then enter the separator 20 through the annular space formed by the shroud 26 and the electric pump unit. The positive effect of using the shroud 26 is that sand and scale prevention measures can be taken for the well fluid entering the pump. Avoid oil well sanding and scale damage to the electric pump, and at the same time, the speed of the external liquid flow of the submersible motor 22 is accelerated, which speeds up the cooling of the submersible motor 22 and reduces the possibility of motor burnout due to high temperature. In addition, each component in the well-exploration electric pump test oil test production liquid drainage device can be connected by thread or flange.

In a preferred embodiment of this specific embodiment, as shown in FIG. 1 , the device may also include a check valve 17 arranged above the pump head 18. Fluid backflow.

In a preferred embodiment of this specific embodiment, as shown in Figure 1, the device may also include an oil drainer 16 arranged above the check valve 17, and the function of the oil drainer 16 is to be The fluid in the oil pipe 24 is released into the oil jacket annulus to avoid ground contamination.

In a preferred embodiment of this specific embodiment, as shown in FIG. 1, the device may also include a centralizer 28 fixedly connected to the lower end of the slotted screen 27, and the centralizer 28 is used to form a centralizer for the entire downhole pipe string. Function, to avoid encountering obstruction during operation and wear of the drainage device for oil testing and production testing of the electric pump of the exploratory well.

In a preferred embodiment of this specific embodiment, as shown in Figure 1, the device can also include a protector 21 arranged on the oil pipe 24 between the separator 20 and the submersible motor 22, the function of the protector 21 is Supplement oil for the submersible motor 22 while isolating the well fluid to avoid burning the pump.

This specific embodiment also provides a drainage system for oil testing and production testing of electric pumps for exploration wells, as shown in Figure 2 and Figure 3, the system includes the drainage system for oil testing and production testing of electric pumps for exploration wells as described in any one of the above embodiments The ground control device includes a generator 5, a transformer 10, a frequency conversion control cabinet 9, and a junction box 7 connected in sequence through wires 6, and the signal output terminal 7 of the junction box passes through the ground cable 13 and the downhole cable 25. It is connected with the signal input end of the submersible motor 22.

Concretely, generator 5 can adopt diesel generator, and its effect is to convert the energy of burning diesel oil into electric energy, and the effect of transformer 10 is to convert the voltage output by generator 5 to the rated voltage of downhole submersible motor 22 work, frequency conversion control The function of the cabinet 9 is to change the frequency of the current. By changing the frequency of the current, the rotating speed of the submersible motor 22 is controlled to finally change the displacement of the centrifugal pump 19. At the same time, the frequency conversion control cabinet 9 also has the function of filtering, and the output current of the transformer 10 The waveform becomes a waveform suitable for the operation of the downhole submersible motor 22, eliminating the influence of harmonics, so that the ground control device can complete several work processes of power generation, power transformation, and control.

In a preferred embodiment of this specific embodiment, as shown in Figure 2, the ground control device can be arranged in a control room 1, and the control room 1 includes a skid-mounted base 4 for mobile or fixed installation, and the skid-mounted base The effect of 4 is to carry the weight of control room 1 when moving and placing. During construction, the control room 1 can be placed in a designated position around the wellhead as a whole through the skid-mounted base 4, and the power can be transmitted to the exploratory well electric pump oil test production and liquid drainage device through the ground cable 13 and the downhole cable 25. At the same time, the downhole test The signal is transmitted to the control room 1 through the downhole cable 25, and can be read on the instrument of the frequency conversion control cabinet 9 in the control room 1.

In a preferred embodiment of this specific embodiment, as shown in FIG. 2 , a sound-absorbing air inlet slot 8 and a sound-absorbing air outlet slot 2 are respectively arranged on the walls on both sides of the control room 1 . The function of the sound-absorbing air inlet slot 8 and the sound-absorbing air outlet slot 2 is to reduce the intensity of the noise transmitted from the inside of the control room 1 to the outside, so as to ensure that the overall device will not cause noise pollution to the surrounding environment.

In a preferred embodiment of this specific embodiment, as shown in Figure 2, a flue 11 and a flue muffler 12 are arranged on the control room 1, the lower exhaust port of the flue 11 communicates with the generator 5, and the flue The upper exhaust port of 2 communicates with the outside world through the roof of the control room 1, and the flue muffler 12 is arranged on the upper exhaust port of the flue 11. The flue 11 is used to discharge the smoke generated by the generator 5 , and the flue muffler 12 is used to reduce the noise generated by the generator 5 .

In a preferred embodiment of this specific embodiment, as shown in FIG. 2 , an isolation foundation 3 is provided between the floor of the control room 1 and the generator 5 . The isolation foundation 3 is used to place the generator 5 and has functions of shock absorption and insulation.

The working process of the oil testing and production testing liquid drainage system of the exploration well electric pump provided in this specific embodiment includes: lowering the oil testing and production testing liquid drainage device of the exploration well electric pump to the underground through the operating machine, and passing the surface cable 13 and the downhole cable 25 The surface control device is connected with the submersible motor 22 in the oil test production and liquid drainage device of the exploration well electric pump. The exploratory well electric pump oil test production test liquid drainage device has the functions of liquid drainage, testing, sand control, etc., and the displacement can meet the needs of exploratory well large volume fracturing liquid drainage. The ground control device can adopt a skid-mounted structure to provide power for the entire process, and also has power conversion and control functions. When in use, the ground control device can be manually placed on the designated position on the ground around the wellhead, and the electric energy provided by the ground control device drives the work of the well exploration electric pump oil test production and liquid drainage device. The frequency conversion control cabinet 9 implements frequency conversion control on the submersible motor 22, and the working condition parameters measured by the downhole tester 23 are transmitted to the frequency conversion control cabinet 9 through the downhole cable 25 and the ground cable 13, and the downhole test parameters are read from the frequency conversion control cabinet 9.

To sum up, in summary, the present invention uses the electric pump unit as the lifting device for the downhole drainage of exploratory wells. are all lower than 100 cubic meters per day, and the drainage system provided by the invention can reach 300 cubic meters per day, which solves the problem of slow drainage speed after large-scale volume fracturing of exploration wells; at the same time, the present invention It also includes a deflector device, which changes the flow channel of the liquid into the pump. The lower part of the deflector is connected to the screen, which can play a role in sand control. The metal anti-scaling device achieves the purpose of anti-scaling, so that the tester can easily measure the parameters of the downhole working conditions. After the completion of the oil test and production test, the downhole electric pump string system can be directly used as the production string without pulling out; in addition, The ground device provided by the present invention is a set of multi-functional control room, which integrates functions such as power generation, power transformation, and control. By reading the downhole test data on the ground, it is possible to have an accurate understanding of the reservoir and obtain more reliable oil testing. In conclusion, when the oil test and production test are completed, the control room can be easily moved to the next construction exploration well, which fully meets the technical requirements for drainage of the exploration well.

Of course, the above-mentioned embodiments of the present invention are only proposed for ease of understanding. According to the foregoing, those skilled in the art can completely change or combine one or more of the features according to specific conditions during actual implementation. Therefore, The replacement of equivalent components made by any person skilled in the art without departing from the concept and scope of the present invention, or the equivalent changes and modifications made according to the patent protection scope of the present invention shall still fall within the scope covered by this patent .

Claims (10)

1. A well-exploration electric pump oil test oil test production drainage device, the lower end of the device is arranged in the oil layer (29) at the bottom of the electric pump wellhead (14), it is characterized in that the device includes sequentially passing through from top to bottom The pump head (18), centrifugal pump (19), separator (20), submersible motor (22), tester (23) and slotted screen (27) connected by oil pipe (24), said device also includes Wrap the outer shroud (26) of separator (20), submersible motor (22) and tester (23). 2. The liquid drainage device for exploration well electric pump oil test production test as claimed in claim 1, characterized in that, the device also includes a check valve (17) arranged above the pump head (18) to prevent The fluid in the oil pipe (24) flows back. 3. The liquid drainage device for oil testing and production testing of electric pumps for exploration wells as claimed in claim 2, characterized in that the device also includes an oil drain (16) arranged above the check valve (17) to perform pump inspection operations The fluid in the oil pipe (24) can be released into the oil jacket annulus at the same time. 4. The liquid drainage device for exploration well electric pump oil testing and production testing as claimed in claim 1, characterized in that, said device also includes a centralizer (28) fixedly connected to the lower end of the slotted screen (27), for said device The above-mentioned device forms a righting effect, avoiding resistance and wear of the device during operation. 5. The electric well pump test oil test production liquid drainage device according to claim 1, characterized in that, the device also includes a protector (21) arranged between the separator (20) and the submersible motor (22) ), for oil replenishment for the submersible motor (22), while isolating the well fluid to avoid burning the pump. 6. A liquid drainage system for exploration well electric pump oil test production test, characterized in that, the system includes the oil exploration test well electric pump liquid drainage device and ground control device as described in any one of claims 1-5, The ground control device includes a generator (5), a transformer (10), a frequency conversion control cabinet (9) and a junction box (7) connected in sequence by wires (6), and the signal output terminal (7) of the junction box is connected through a ground cable (13) and downhole cable (25) are connected with the signal input end of submersible motor (22). 7. The electric pump test oil drainage system according to claim 6, characterized in that, the ground control device is arranged in a control room (1), and the control room (1) includes a skid-mounted base (4 ) to move or fix the setting. 8. The liquid drainage system for exploration well electric pump oil test production test as claimed in claim 7, characterized in that, on the walls on both sides of the control room (1) are respectively provided with a sound-absorbing air inlet groove (8) and a sound-absorbing air outlet groove (2). 9. The liquid drainage system for exploration well electric pump oil testing and production testing as claimed in claim 7, characterized in that, the control room (1) is provided with a flue (11) and a flue silencer (12), and the flue ( The lower exhaust port of 11) communicates with the generator (5), the upper exhaust port of the flue (2) communicates with the outside world through the roof of the control room (1), and the flue silencer (12) is arranged on the flue ( 11) on the upper exhaust port. 10. The electric well pump testing oil drainage system according to claim 7, characterized in that an isolation foundation (3) is provided between the floor of the control room (1) and the generator (5).