Oil well flow probe and detection liquid high-speed injection device thereof

Abstract

The invention discloses a high-speed detection liquid spraying device which comprises a shell, a containing cavity, a first elastic piece, a piston connected with the first elastic piece, a driving motor and a center rod connected with an output shaft of the driving motor. Detection liquid is contained in the containing cavity, and a spraying hole communicated with the containing cavity is formed in the shell; the center rod is sleeved with the inner edge of the piston, a clamping groove extending in the circumferential direction is formed in the outer edge of the center rod, a second elastic piece and a clamping block connected with the second elastic piece are arranged on the piston, and the second elastic piece enables the clamping block to abut against the interior of the clamping groove through radial elastic force; the depth of the clamping groove gradually changes in the circumferential direction, and one end of the clamping groove is flush with the outer edge of the center rod. The injection speed of the detection liquid can be increased, sufficient detection liquid can be rapidly injected within a short time, the testing requirement of a flow logging method based on an underground manual electric field is met, and the oil well flow detection precision is optimized. The invention further discloses an oil well flow probe which has the beneficial effects mentioned above.

Description

Technical Field

[0001] The present invention relates to the technical field of oil exploration, and particularly to a high-speed jet device for detection fluid. The present invention also relates to an oil well flow probe. Background Art

[0002] During the development of oil fields, it is often necessary to lower special logging instruments into oil wells to measure the status of the oil-water mixed fluid produced from each oil layer, that is, production profile logging. The wellbore of an oil field production well is a steel casing, and the steel casing and the formation are cemented and solidified through cement. In the oil layer section, the steel casing has perforation holes connected to the formation, forming channels for fluid flow inside and outside the casing. Inside the oil field production well is a flowing oil-water mixed fluid. Oil field development logging requires using special logging instruments to measure the production status of crude oil and water in the steel casing hundreds to thousands of meters underground. The water absorption of different formation layers may be different. Understanding the flow rate of the fluid produced or inhaled by each perforated interval formation can correctly evaluate the production status of the oil well and the exploitation characteristics of the oil layer. Measuring the amount of fluid produced or inhaled by different perforated interval formations per unit time is called flow rate logging, and flow rate logging is an important means to evaluate the production and injection effects of oil production wells and injection wells in oil fields.

[0003] The traditional flow rate logging method mainly uses isotope tracer logging. The isotope tracer logging method is mainly used in combination with an ejector. During the test, the radioactive tracer is ejected into the wellbore through the ejector carried on the flow probe, so that the radioactive tracer flows with the well fluid in an aggregated form. When the radioactive tracer passes through the natural gamma detector on the flow probe, the detector will have an obvious abnormal display, and there will be obvious waveform changes in the time and amplitude coordinate system. Then, based on the time and position of the isotope peak, the oil well flow rate can be calculated. However, the isotope tracer logging method uses radioactive tracers for measurement. Since isotopes are usually radioactive substances and have strong radioactive pollution, the pollution of the isotope tracer logging method is serious and it can cause radiation damage to the human body.

[0004] As an improvement, the flow rate logging method based on the downhole artificial electric field has currently replaced the isotope tracer logging method and become the mainstream. Such as Figure 1As shown, this logging method also needs to be used in conjunction with an ejector. During testing, a flow probe needs to be lowered into the oil production well. The inside of the flow probe is a stainless steel cylinder, and the outside is an insulating layer. There are two sets of metal rings embedded on the insulating layer, with each set including 4 metal rings and being hierarchically distributed in the height direction. Among them, the top and bottom metal rings of each set are respectively electrode rings powered by low-voltage direct current to form a direct current electric field, and the middle two metal rings are both measurement rings to measure the electrical signals generated when the detection liquid (usually an environmentally friendly ionic solution) flows through the middle two measurement rings. The ejector is installed at the bottom of the probe. As the pumping unit works, the oil-water mixed fluid in the well flows upward. The ejector sprays the detection liquid outward, and the detection liquid moves upward with the well fluid. When it flows through the two sets of direct current electric fields up and down, two electrical signals will be generated successively. There is a time difference between the two electrical signals, and based on this, the flow rate of the well fluid can be calculated.

[0005] However, the ejectors used in the isotope tracer logging method in the prior art are difficult to adapt to the flow logging method based on the artificial electric field in the well. This is because: this method requires the distance between the spraying position of the detection liquid and the electric field to be as close as possible, usually only 30 mm. If this distance is too large, first, the detection liquid will seriously diffuse in the well fluid, affecting the formation of the measurement signal; second, if the spraying speed is too slow, before the spraying is completed, the detection liquid that has been sprayed first will already reach the electric field, which also affects the formation of the measurement signal. Therefore, this method requires the ejector to be able to quickly spray a sufficient amount of detection liquid. For example, spraying 5 ml of detection liquid within 1 s can ensure the detection accuracy. However, for the existing ejectors, due to the way of driving the piston to move by using a lead screw slider mechanism, to complete one spraying action, multiple steps need to be carried out successively, such as the motor driving the lead screw to rotate, the lead screw and the slider forming a screw drive to realize the conversion from rotational motion to linear motion, and the slider driving the piston to move. The overall transmission chain is relatively long, and the mechanical efficiency is low. Generally, it takes about 5 s to spray 5 ml of detection liquid, resulting in too slow spraying speed and too long spraying time, and then the generated electrical signal has a serious tailing phenomenon, making it difficult to form a stable peak signal and affecting the flow measurement accuracy. In addition, if a high-power high-speed motor is used regardless of cost to accelerate the spraying speed, it will be due to the inevitable instability of the lead screw slider during high-speed rotation, that is, the slider will have serious lateral swing when the lead screw rotates at high speed, resulting in difficulty in stably realizing the high-speed linear motion of the piston.

[0006] Therefore, how to improve the spraying speed of the detection liquid, realize rapid spraying of a sufficient amount of detection liquid in a short time, meet the test requirements of the flow logging method based on the artificial electric field in the well, and optimize the oil well flow detection accuracy is a technical problem faced by those skilled in the art. Summary of the Invention

[0007] The object of the present invention is to provide a detection liquid high-speed injection device, which can improve the injection speed of the detection liquid, and achieve rapid injection of a sufficient amount of detection liquid in a short time, meet the test requirements of the flow logging method based on the downhole artificial electric field, and optimize the flow detection accuracy of the oil well. Another object of the present invention is to provide an oil well flow probe.

[0008] To solve the above technical problems, the present invention provides a detection liquid high-speed injection device, including a housing, a receiving cavity arranged in the housing, a first elastic member installed in the receiving cavity, a piston slidably arranged in the receiving cavity and connected to the first elastic member, a driving motor arranged in the housing, and a central rod rotatably penetrating through the housing and connected to the output shaft of the driving motor;

[0009] The receiving cavity is filled with the detection liquid, and the housing is provided with an injection hole communicated with the receiving cavity;

[0010] The inner edge of the piston is sleeved on the central rod in a loose fit, a clamping groove extending in the circumferential direction is formed on the outer edge of the central rod, a second elastic member and a clamping block connected to the second elastic member are arranged on the piston, and the second elastic member abuts the clamping block against the clamping groove through a radial elastic force;

[0011] The groove depth of the clamping groove gradually changes in the circumferential direction, and one end is flush with the outer edge of the central rod.

[0012] Preferably, two clamping grooves are arranged in the same cross-section of the central rod, and the two clamping grooves are symmetrically distributed about the center;

[0013] Two second elastic members and two clamping blocks are arranged, and the two second elastic members and the two clamping blocks are symmetrically distributed about the center.

[0014] Preferably, multiple groups of clamping grooves are axially distributed along the central rod, the central angle of each clamping groove is 90°, and the phase difference between two adjacent clamping grooves in the axial direction is π / 2.

[0015] Preferably, an installation hole is radially formed on the inner edge of the piston, and the second elastic member and the clamping block are arranged in the installation hole.

[0016] Preferably, multiple injection holes are arranged in the same cross-section of the housing and are evenly distributed in the circumferential direction;

[0017] A limiting member is convexly arranged on the outer edge of the end of the central rod adjacent to the injection hole to form an abutment with the piston.

[0018] Preferably, the housing includes a front shell, a transition section, and a rear shell. One end of the transition section is detachably connected to the front shell, and the other end of the transition section is detachably connected to the rear shell.

[0019] The accommodation cavity is formed in the front shell. The drive motor is installed in the rear shell. The injection holes are formed in the front side wall at the front end of the front shell. The central rod penetrates through the front shell and the transition section and extends into the rear shell.

[0020] Preferably, a pressure balance hole is formed in the rear side wall of the front shell. The pressure balance hole communicates with the cavity of the accommodation cavity located behind the piston, and the injection holes communicate with the cavity of the accommodation cavity located in front of the piston.

[0021] Preferably, it further includes a control board installed in the rear shell, a bus slip ring provided on the control board, and a bus interface provided at the rear end of the central rod. The bus interface is electrically connected to the bus slip ring, and the control board is electrically connected to the control end of the drive motor to supply power to the drive motor and control its working state.

[0022] A bus pin for electrically connecting with the measuring probe of the oil well flow probe is provided on the front end face of the front shell. The bus pin is electrically connected to the bus interface through the central rod.

[0023] Preferably, it further includes an expansion interface provided at the rear end of the rear shell and electrically connected to the control board, and a guiding cone head detachably connected to the rear end of the rear shell.

[0024] The present invention also provides an oil well flow probe, which includes a measuring probe and a detection liquid injection device connected to the measuring probe. Among them, the detection liquid injection device is specifically the detection liquid high-speed injection device described in any one of the above.

[0025] The high-speed injection device for detection liquid provided by the present invention mainly includes a housing, a containing cavity, a first elastic member, a piston, a driving motor, a central rod, and an injection hole. Among them, the housing is the main structure of this device, generally in a cylindrical shape, a circular tubular shape, or a cylindrical shape with a hollow interior, and is mainly used for installing and accommodating the remaining components. The containing cavity is arranged inside the housing, generally located in the front-end area of the housing, that is, adjacent to the end of the measuring probe of the oil well flow probe, and is mainly used for containing a preset amount of detection liquid, and is also used for installing components such as the first elastic member and the piston. The injection hole is opened on the housing, generally located in the front-end area of the housing, adjacent to the metal ring installed on the measuring probe of the oil well flow probe, and extends internally to communicate with the containing cavity, and is mainly used for the detection liquid in the containing cavity to be ejected into the oil well. The first elastic member is installed in the containing cavity, can generate elastic deformation, and the deformation direction is the axial direction of the housing. The end of the first elastic member is connected to the piston. The piston is also installed in the containing cavity and forms a sliding connection with the containing cavity, having a linear motion degree of freedom. The containing cavity is equivalent to a "cylinder block", and the piston can slide in the containing cavity, thereby pushing the detection liquid in the containing cavity to flow and be ejected from the injection hole. At the same time, there is no connecting rod on the piston, and it is only connected to the first elastic member. Therefore, its power source is not the driving motor, but the elastic potential energy of the first elastic member - when filling the detection liquid into the containing cavity, the first elastic member is compressed and generates elastic compression, having a certain elastic potential energy; when the first elastic member releases the elastic potential energy, it can immediately push the piston to perform a linear motion in the containing cavity, forming a rapid ejection effect on the piston. The driving motor is arranged inside the housing, generally located in the rear-end area of the housing; the central rod passes through the housing, and one end (the rear end) of the central rod is connected to the output shaft of the driving motor and can perform a rotational motion under the drive of the driving motor. At the same time, the central rod passes through the piston, but does not form a direct connection with the piston. Instead, the inner edge of the piston is sleeved on the central rod, that is, when the central rod performs a rotational motion, the piston is not affected and does not rotate synchronously with it.

[0026] Importantly, a clamping groove is formed on the outer edge of the central rod, and at the same time, a second elastic member and a clamping block are arranged on the piston. Among them, the clamping groove extends along the circumferential direction of the central rod, forming an arc-shaped groove structure, and the groove depths at various parts of the clamping groove are not the same, but gradually change from one end to the other end of its circumference, and the depth of the shallowest end (the shallow end) is zero, which is equivalent to being flush with the outer edge of the central rod. At the same time, the second elastic member is connected to the clamping block. The elastic force direction of this second elastic member is the radial direction of the central rod, and it has a pre-compression amount to form an elastic pre-tightening force towards the inside in the radial direction on the clamping block. This elastic pre-tightening force enables the clamping block to tightly abut in the clamping groove of the central rod, ensuring a stable clamping fit between the clamping block and the clamping groove, realizing the locking of the clamping block and the piston, or when the clamping block is disengaged from the clamping fit with the clamping groove, enabling the clamping block to abut on the outer edge surface of the central rod to form a sliding friction.

[0027] Thus, when the detection liquid high-speed injection device provided by the present invention measures the fluid flow rate in an oil well through the flow logging method of the downhole artificial electric field, only a small rotation of the central rod is driven by the driving motor, so that the clamping block rotates relatively from the deep end to the shallow end of the clamping groove, that is, the unlocking of the clamping block is realized. At the moment of unlocking, the elastic potential energy of the first elastic member is immediately released, and the piston is ejected and starts quickly, rapidly pushing the detection liquid in the accommodating cavity through the injection hole and injecting it into the external oil well, achieving the effect of quickly injecting a sufficient amount of detection liquid in a short time. In addition, when the detection liquid does not need to be injected, the clamping block is always abutted in the clamping groove under the action of the elastic pre-tightening force of the second elastic member, maintaining the locked state, thereby ensuring that the piston remains fixed and avoiding the situation of misinjecting the detection liquid.

[0028] In summary, the detection liquid high-speed injection device provided by the present invention can improve the injection speed of the detection liquid, realize the rapid injection of a sufficient amount of detection liquid in a short time, meet the test requirements of the flow logging method based on the downhole artificial electric field, and optimize the detection accuracy of the oil well flow rate. Description of the Drawings

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required to be used in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained according to the provided drawings without creative efforts.

[0030] Figure 1 It is a schematic diagram of the flow logging method based on the downhole artificial electric field in the prior art.

[0031] Figure 2 It is a schematic diagram of the overall structure of a specific embodiment provided by the present invention.

[0032] Figure 3 It is a schematic diagram of the phase change of two adjacent sets of clamping grooves in the axial direction during the rotation of the central rod.

[0033] Figure 4 It is a schematic diagram of the connection method between the detection liquid high-speed injection device and the measurement probe.

[0034] Among them, Figure 2 — Figure 4 In:

[0035] Shell - 1, accommodation chamber - 2, first elastic member - 3, piston - 4, drive motor - 5, central rod - 6, injection hole - 7, limiting member - 8, pressure balance hole - 9, control board - 10, bus slip ring - 11, bus interface - 12, expansion interface - 13, fixed pin - 14, sealing ring - 15, coupling - 16, measurement probe - 17;

[0036] Front shell - 101, transition section - 102, rear shell - 103, bus pin - 104, guiding cone - 105;

[0037] Second elastic member - 41, clamping block - 42, mounting hole - 43;

[0038] Clamping groove - 61;

[0039] Connection jack - 171. Specific embodiments

[0040] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0041] Please refer to Figure 2 , Figure 2 , which is a schematic diagram of the overall structure of a specific embodiment provided by the present invention.

[0042] In a specific embodiment provided by the present invention, the detection liquid high - speed injection device mainly includes a shell 1, an accommodation chamber 2, a first elastic member 3, a piston 4, a drive motor 5, a central rod 6, and an injection hole 7.

[0043] Among them, the shell 1 is the main structure of this device, generally in a cylindrical shape, circular tubular shape or a cylindrical shape with a hollow interior, mainly used for installing and accommodating the remaining components.

[0044] The accommodation chamber 2 is arranged inside the shell 1, generally in the front - end area of the shell 1 (taking the direction towards the measurement probe 17 of the oil well flow probe as the front), that is, adjacent to the end of the measurement probe 17 of the oil well flow probe, mainly used for containing a preset amount of detection liquid, and also used for installing components such as the first elastic member 3 and the piston 4.

[0045] The injection hole 7 is opened on the shell 1, generally in the front - end area of the shell 1, adjacent to the metal ring installed on the measurement probe 17 of the oil well flow probe, and extends internally to communicate with the accommodation chamber 2, mainly used for spraying the detection liquid in the accommodation chamber 2 into the oil well.

[0046] The first elastic member 3 is installed in the accommodating cavity 2, capable of elastic deformation, and the deformation direction thereof is the axial direction of the housing 1. Usually, a spring is used, and the end of the first elastic member 3 is connected to the piston 4. The piston 4 is also installed in the accommodating cavity 2 and forms a sliding connection with the accommodating cavity 2, having a linear motion degree of freedom. The accommodating cavity 2 is equivalent to a "cylinder block", and the piston 4 can slide in the accommodating cavity 2, thereby pushing the detection liquid in the accommodating cavity 2 to flow out from the ejection hole 7.

[0047] At the same time, there is no connecting rod on the piston 4, and it is only connected to the first elastic member 3. Therefore, its power source is not the driving motor 5, but the elastic potential energy of the first elastic member 3 - when filling the detection liquid into the accommodating cavity 2, the first elastic member 3 is compressed and generates elastic compression, having a certain elastic potential energy; when the first elastic member 3 releases the elastic potential energy, it can immediately push the piston 4 to perform a linear motion in the accommodating cavity 2, forming a rapid ejection effect on the piston 4.

[0048] The driving motor 5 is arranged in the housing 1, generally located in the rear region of the housing 1; the central rod 6 is inserted through the housing 1, and one end (rear end) of the central rod 6 is connected to the output shaft of the driving motor 5 and can perform a rotational motion under the drive of the driving motor 5. At the same time, the central rod 6 passes through the piston 4, but does not form a direct connection with the piston 4. Instead, the inner edge of the piston 4 is sleeved on the central rod 6 loosely, that is, when the central rod 6 performs a rotational motion, the piston 4 is not affected and does not rotate synchronously therewith. Generally, the output shaft of the driving motor 5 is connected to the rear end of the central rod 6 through a coupling 16.

[0049] Importantly, a clamping groove 61 is formed on the outer edge of the central rod 6, and at the same time, a second elastic member 41 and a clamping block 42 are arranged on the piston 4. Among them, the clamping groove 61 extends along the circumferential direction of the central rod 6, forming an arc-shaped groove structure, and the groove depths at various positions of the clamping groove 61 are not the same, but gradually change from one end to the other end in its circumferential direction, and the depth of the shallowest end (shallow end) of the groove depth is zero, which is equivalent to being flush with the outer edge of the central rod 6. At the same time, the second elastic member 41 is connected to the clamping block 42. The second elastic member 41 usually uses a spring, and its elastic force direction is the radial direction of the central rod 6, and it has a pre-compression amount to form an elastic pre-tightening force in the radially inward direction on the clamping block 42. This elastic pre-tightening force makes the clamping block 42 tightly abut against the clamping groove 61 of the central rod 6, ensuring a stable clamping fit between the clamping block 42 and the clamping groove 61, realizing the locking of the clamping block 42 and the piston 4, or when the clamping block 42 is disengaged from the clamping groove 61, making the clamping block 42 abut against the outer edge surface of the central rod 6 to form a sliding friction.

[0050] Thus, when the detection liquid high-speed injection device provided in this embodiment measures the fluid flow rate in an oil well through the flow logging method of the downhole artificial electric field, only by driving the central rod 6 to rotate slightly by the driving motor 5, the clamping block 42 can be rotated relatively from the deep end to the shallow end of the clamping groove 61, that is, the unlocking of the clamping block 42 is realized. At the moment of unlocking, the elastic potential energy of the first elastic member 3 is immediately released, and the piston 4 is ejected and starts quickly, rapidly pushing the detection liquid in the accommodating cavity 2 to be sprayed into the external oil well through the spray hole 7, achieving the effect of quickly spraying a sufficient amount of detection liquid in a short time. In addition, when the detection liquid does not need to be sprayed, the clamping block 42 is always abutted in the clamping groove 61 under the action of the elastic pre-tightening force of the second elastic member 41, maintaining the locked state, thereby ensuring that the piston 4 remains fixed and avoiding the situation of mis-spraying the detection liquid.

[0051] In summary, the detection liquid high-speed injection device provided in this embodiment can improve the injection speed of the detection liquid, realize quickly spraying a sufficient amount of detection liquid in a short time, meet the test requirements of the flow logging method based on the downhole artificial electric field, and optimize the detection accuracy of the oil well flow rate.

[0052] In a specific embodiment regarding the clamping groove 61, in order to improve the locking stability of the piston 4 and the balance of the abutting force on the central rod 6, in this embodiment, two clamping grooves 61 are simultaneously arranged in the same cross-section of the central rod 6, and the two clamping grooves 61 are symmetrically distributed about the center of the central rod 6, that is, the two clamping grooves 61 are respectively distributed at the radial two ends of the central rod 6. Correspondingly, two second elastic members 41 and two clamping blocks 42 are also simultaneously arranged, and the two second elastic members 41 are symmetrically distributed about the center of the central rod 6, and the two clamping blocks 42 are symmetrically distributed about the center of the central rod 6. With such a setting, in the locked state, the two clamping blocks 42 are respectively abutted against the deep ends of the two clamping grooves 61, and the abutting forces formed on the central rod 6 are opposite and equal in the radial direction, so as to cancel each other out, ensuring that the central rod 6 is stressed evenly. Furthermore, when the central rod 6 performs a rotational motion, its motion state tends to be stable and balanced, avoiding eccentric vibration during the rotation process; at the same time, the two clamping blocks 42 are simultaneously abutted against the two clamping grooves 61, which can also improve the locking stability of the piston 4. When the driving motor 5 drives the central rod 6 to rotate, the two clamping blocks 42 respectively rotate from the deep end to the shallow end relative to their corresponding clamping grooves 61 to achieve synchronous unlocking.

[0053] Furthermore, considering that when detecting the fluid flow rate in an oil well once, usually only 5 ml of the detection liquid needs to be ejected within 1 s, and the accommodation cavity 2 usually contains far more detection liquid than that used for a single detection, generally enough for 3 to 6 or more detections; and, for a single detection, the more detection liquid is not necessarily better. If the ejection volume is too large, it is easy to have the problem of long signal tailing caused by rapid diffusion; if the ejection volume is too small, it is difficult to generate a stable and clear electrical signal. In view of this, to avoid ejecting all the detection liquid in a single detection and ensure that the ejection volume for each detection tends to be consistent, in this embodiment, there are multiple groups of clamping grooves 61 evenly distributed along the axial direction of the central rod 6, such as 2 to 5 groups, etc., and each group of clamping grooves 61 is distributed at the front end of the central rod 6, that is, in the area corresponding to the accommodation cavity 2. With such a setting, since the inner diameter of the accommodation cavity 2 is fixed, when the piston 4 slides in the accommodation cavity 2, the displacement of the piston 4 and the amount of the detection liquid pushed for ejection maintain a fixed proportional relationship. Furthermore, on the basis that each group of clamping grooves 61 is evenly distributed along the axial direction of the central rod 6, the distance between any two adjacent groups of clamping grooves 61 is equal. Correspondingly, when the piston 4 moves between any two adjacent groups of clamping grooves 61, the amount of the detection liquid ejected is also equal, so that multiple equal-volume ejections can be completed. Generally, when the piston 4 moves between any two adjacent groups of clamping grooves 61, the amount of the detection liquid ejected is fixed at 5 ml. Of course, the amount of the detection liquid ejected in a single ejection is not fixed and can also be adjusted, such as adjusting the distance between two adjacent groups of clamping grooves 61 and / or adjusting the inner diameter of the accommodation cavity 2, etc.

[0054] As Figure 3 shown, Figure 3 FIG. is a schematic diagram of the phase change of any two adjacent groups of clamping grooves 61 in the axial direction during the rotation of the central rod 6.

[0055] Moreover, considering that the central rod 6 usually performs continuous (or intermittent) directional rotational movement during the measurement operation, and to form multiple injections, after the clamping block 42 unlocks and disengages from the current clamping groove 61, when it is ejected with the piston 4 to the next adjacent (front) clamping groove 61, it should be able to re-engage into the deep end of the new clamping groove 61 to form a lock, waiting to disengage from the new clamping groove 61 during the next injection operation, and so on to achieve multiple injection operations. For this purpose, in this embodiment, the central angle of each clamping groove 61 is 90°, and the phase angle between two adjacent sets of clamping grooves 61 in the axial direction differs by π / 2, that is, the central angle between two adjacent clamping grooves 61 in the circumferential direction is 90°. With such a setting, in any two adjacent sets of clamping grooves 61, when the two clamping blocks 42 are both abutted against the deep ends (the s ends shown in the figure) of the two clamping grooves 61 in the latter group (the left side shown in the figure), one of the two clamping grooves 61 in the latter group is exactly located in the first quadrant within the cross-section of the central rod 6, and the other is exactly located in the third quadrant within the cross-section of the central rod 6, and the deep ends of the two clamping grooves 61 in the latter group are respectively located at the top and bottom of the central rod 6, and the shallow ends (the q ends shown in the figure) of the two clamping grooves 61 are respectively located on the left and right sides of the central rod 6, then: at this time, one of the two clamping grooves 61 in the former group (the right side shown in the figure) is exactly located in the second quadrant within the cross-section of the central rod 6, and the other is exactly located in the fourth quadrant within the cross-section of the central rod 6, and the deep ends of the two clamping grooves 61 in the former group are respectively located on the left and right sides of the central rod 6, and the shallow ends of the two clamping grooves 61 are respectively located at the top and bottom of the central rod 6.

[0056] Continuing from the above, when the central rod 6 rotates counterclockwise by 90° as shown in Figure 3 the figure, the two clamping grooves 61 in the latter group simultaneously lift the two clamping blocks 42 and unlock the two clamping blocks 42 at the same time; at this time, since the two clamping grooves 61 in the former group rotate synchronously with the central rod 6 by 90°, they respectively enter the first and third quadrants within the cross-section of the central rod 6, and the deep ends of the two clamping grooves 61 are respectively located at the top and bottom of the central rod 6; when the first elastic member 3 ejects the piston 4, when the two clamping blocks 42 move axially to the positions of the two clamping grooves 61 in the former group, they can re-engage into the deep ends of the two clamping grooves 61 in the former group under the action of the elastic pre-tightening force of the second elastic member 41 to achieve secondary locking, and the piston 4 also pauses at the current position. The same principle applies to subsequent third, fourth lockings, and so on, and so on until the multiple quantitative injection operations of the detection liquid are completed.

[0057] In addition, considering that the piston 4 may impact the front end cavity wall of the accommodation cavity 2 during the last injection, and the huge impact force may cause wear to the cavity wall of the accommodation cavity 2 or the piston 4. For this reason, a limiting member 8 is added in this embodiment. Specifically, the limiting member 8 protrudes from the outer edge of the end of the central rod 6 adjacent to the injection hole 7 and maintains a certain distance from the front end cavity wall of the accommodation cavity 2. Specifically, a limiting ring structure, a limiting convex column structure, a limiting tooth structure, etc. can be adopted, which is mainly used to form an abutment with the front end face of the piston 4, so as to limit the front end face of the piston 4 at the position of the limiting member 8 after the last injection, preventing the piston 4 from directly impacting the front end cavity wall of the accommodation cavity 2 and causing damage.

[0058] To facilitate the installation of the second elastic member 41 and the clamping block 42 on the piston 4, in this embodiment, an installation hole 43 with a certain depth is radially formed on the inner edge of the piston 4, and the second elastic member 41 and the clamping block 42 are both arranged in the installation hole 43. Specifically, the second elastic member 41 is arranged in the installation hole 43 along the radial direction of the central rod 6 and has a certain pre-compression amount. At the same time, one end of the second elastic member 41 is connected to the bottom wall of the installation hole 43, and the other end is connected to the clamping block 42, so as to always maintain an elastic pre-tightening force on the clamping block 42 along the radial direction inward or toward the central rod 6. Of course, the second elastic member 41 and the clamping block 42 can also be installed on the end face of the piston 4 and other positions through components such as an adapter bracket.

[0059] In a specific embodiment regarding the injection hole 7, to improve the injection efficiency, a plurality of injection holes 7 are simultaneously formed on the housing 1, such as 4 to 8, etc., and each injection hole 7 is formed in the same cross-section of the housing 1 and is evenly distributed along the circumferential direction of the housing 1. At the same time, during use, a nozzle is generally installed on the injection hole 7 to adjust parameters such as injection flow rate, injection pressure, and injection distance through the nozzle. And after the nozzle is installed, the detection liquid in the accommodation cavity 2 cannot naturally flow out under normal circumstances, avoiding liquid leakage. Only under the push of the piston 4 can it be ejected through the nozzle. In addition, when injecting the detection liquid into the accommodation cavity 2, usually a plug is used to block the redundant injection holes 7, leaving only one injection hole 7 for liquid injection, and at the same time facilitating the compression of the first elastic member 3.

[0060] In a specific embodiment of the housing 1, the housing 1 is specifically a multi-section splicing structure, mainly including a front shell 101, a transition section 102, and a rear shell 103. Among them, the front shell 101 is located at the front end of the housing 1, the rear shell 103 is located at the rear end of the housing 1, the transition section 102 is located in the middle of the housing 1, and one end of the front shell 101 is detachably connected to the transition section 102, such as by screw connection, etc., and the other end of the rear shell 103 is detachably connected to the transition section 102, such as by screw connection, etc. Correspondingly, the accommodation cavity 2 is specifically opened in the front shell 101, the drive motor 5 is specifically installed in the rear shell 103, the injection hole 7 is specifically opened on the front side wall of the front end of the front shell 101, and the central rod 6 penetrates through the front shell 101 and the transition section 102 and extends into the rear shell 103. With such a setting, the front shell 101 and the rear shell 103 are isolated from each other by the transition section 102, which can prevent the detection liquid in the accommodation cavity 2 in the front shell 101 from entering the rear shell 103. Of course, sealing rings 15 can also be installed at the connection position between the front shell 101 and the transition section 102, at the connection position between the rear shell 103 and the transition section 102, between the inner edge surface of the piston 4 and the outer edge surface of the central rod 6, etc., to ensure the sealing performance through the sealing rings 15.

[0061] Furthermore, to prevent the first elastic member 3 from rotating during elastic deformation or rubbing against the inner wall of the accommodation cavity 2, a fixing pin 14 is added in this embodiment. Specifically, the fixing pin 14 is arranged in the front shell 101 and at least two are provided. One fixing pin 14 is arranged on the rear end face of the piston 4 and is connected to the front end of the first elastic member 3, and the other fixing pin 14 is arranged on the front end face of the transition section 102 and is connected to the rear end of the first elastic member 3.

[0062] In addition, considering that when the pressure in the well is relatively high, the elastic force of the first elastic member 3 may be difficult to quickly eject the detection liquid in the accommodation cavity 2. For this, a pressure balance hole 9 is added in this embodiment. Specifically, the pressure balance hole 9 is opened on the front shell 101, specifically on the rear side wall of the front shell 101, and the pressure balance hole 9 communicates with the cavity of the accommodation cavity 2 behind the piston 4, while the injection hole 7 communicates with the cavity of the accommodation cavity 2 in front of the piston 4. With such a setting, the external pressure is introduced into the rear side of the accommodation cavity 2 by the pressure balance hole 9, so that the external pressures on the front and rear end faces of the piston 4 cancel each other out, thereby ensuring that the elastic force of the first elastic member 3 can drive the piston 4 to perform a rapid ejection movement. At the same time, in practical applications, the pressure balance hole 9 can also serve as an observation window. By observing the internal axial gap of the first elastic member 3 through the pressure balance hole 9, the staff can roughly judge the elastic deformation state of the first elastic member 3 and the position of the piston 4.

[0063] To facilitate the power supply to the drive motor 5 and the control of its working state, a control board 10, a bus slip ring 11, and a bus interface 12 are added in this embodiment. Among them, the control board 10 is installed in the rear shell 103 and is electrically connected and signal-connected to the control end of the drive motor 5 through cables and signal cables, so as to supply power to the drive motor 5 and send control instructions. The bus slip ring 11 is arranged on the control board 10, and the bus interface 12 is arranged at the rear end position of the central rod 6. Moreover, the bus interface 12 is electrically connected to the bus slip ring 11, and the bus slip ring 11 is also electrically connected to the control board 10. In this way, the measurement probe 17 of the oil well flow probe is electrically connected to the control board 10 through the bus interface 12 and the bus slip ring 11. Specifically, the bus slip ring 11 is circular and maintains a connection with the bus interface 12 in a surface contact manner. Since the central rod 6 needs to rotate, and the bus interface 12 is arranged on the central rod 6 and rotates synchronously with the central rod 6, the electrical connection between the bus interface 12 and the bus slip ring 11 can be maintained during the movement of the central rod 6, and at the same time, the situation of connection breakage between the bus interface 12 and the bus slip ring 11 can be avoided.

[0064] As Figure 4 shown, Figure 4 Figure 1 is a schematic diagram of the connection method between the detection liquid high-speed injection device and the measurement probe 17.

[0065] Furthermore, to facilitate the electrical connection between the bus interface 12 and the measurement probe 17 of the oil well flow probe, a bus pin 104 is added in this embodiment. Specifically, the bus pin 104 is arranged on the front end face of the front shell 101 and is mainly used to form an electrical connection with the measurement probe 17 of the oil well flow probe. Generally, a connection jack 171 is opened on the rear end face of the measurement probe 17, and the bus pin 104 is used to form an axial hole plug-in and unplugging fit with the connection jack 171, so as to realize the axial docking and electrical connection between the two. At the same time, the rear end of the bus pin 104 is electrically connected to the bus interface 12 through the internal cavity of the central rod 6.

[0066] Moreover, to achieve function expansion, an expansion interface 13 is also arranged at the rear end of the rear shell 103 in this embodiment. The expansion interface 13 is electrically connected to the control board 10 and is mainly used to form an electrical connection with other instruments or related accessories.

[0067] In addition, to ensure that the rear shell 103 can be easily inserted into the deep part of the viscous fluid, a guiding cone head 105 is added at the rear end of the rear shell 103 in this embodiment. Specifically, the guiding cone head 105 is conical and is detachably connected to the rear end of the rear shell 103, such as by threaded connection or the like.

[0068] This embodiment also provides an oil well flow probe, which mainly includes a measurement probe 17 and a detection liquid injection device connected to the measurement probe 17. Among them, since the detection liquid injection device adopts all the technical solutions of the above-mentioned detection liquid high-speed injection device embodiment, therefore, the oil well flow probe provided by this embodiment also has all the technical effects brought by the technical solutions of the above-mentioned embodiment, which will not be elaborated here.

[0069] It should be noted that the detection liquid high-speed injection device provided by this embodiment, in combination with the flow logging method of the downhole artificial electric field, can not only meet the flow detection of production wells in the heavy oil block of the oilfield, but also be applicable to the flow detection of scenarios such as light oil and water wells.

[0070] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A high-speed injection device for a detection liquid, characterized in that, It includes a housing (1), a receiving cavity (2) provided in the housing (1), a first elastic member (3) installed in the receiving cavity (2), a piston (4) slidably provided in the receiving cavity (2) and connected to the first elastic member (3), a driving motor (5) provided in the housing (1), and a central rod (6) rotatably passing through the housing (1) and connected to the output shaft of the driving motor (5); The receiving cavity (2) is filled with a detection liquid, and a spraying hole (7) communicating with the receiving cavity (2) is provided on the housing (1); The inner edge of the piston (4) is sleeved on the central rod (6) loosely, a clamping groove (61) extending circumferentially is provided on the outer edge of the central rod (6), a second elastic member (41) and a clamping block (42) connected to the second elastic member (41) are provided on the piston (4), and the second elastic member (41) abuts the clamping block (42) against the clamping groove (61) by a radial elastic force; The groove depth of the clamping groove (61) gradually changes circumferentially, and one end is flush with the outer edge of the central rod (6).

2. The high-speed liquid jetting device for detection liquid according to claim 1, wherein, Two clamping grooves (61) are provided in the same cross-section of the central rod (6), and the two clamping grooves (61) are symmetrically distributed about the center; Two second elastic members (41) and two clamping blocks (42) are provided, and the two second elastic members (41) and the two clamping blocks (42) are symmetrically distributed about the center.

3. The high-speed liquid jetting device for detection liquid according to claim 2, wherein, Multiple groups of clamping grooves (61) are uniformly distributed along the axial direction of the central rod (6), the central angle of each clamping groove (61) is 90°, and the phase difference between two adjacent groups of clamping grooves (61) in the axial direction is π / 2.

4. The high-speed liquid jetting device for detection liquid according to claim 1, wherein An installation hole (43) is provided in the inner edge of the piston (4) in the radial direction, and the second elastic member (41) and the clamping block (42) are both provided in the installation hole (43).

5. The high-speed liquid jetting device for detection liquid according to claim 1, characterized in that, Multiple spraying holes (7) are provided in the same cross-section of the housing (1) and are uniformly distributed circumferentially; A limiting member (8) is protruded on the outer edge of the end of the central rod (6) adjacent to the spraying hole (7) to form an abutment with the piston (4).

6. The high-speed liquid jetting device for detection liquid according to any one of claims 1-5, characterized in that, The housing (1) includes a front shell (101), a transition section (102), and a rear shell (103). One end of the front shell (101) is detachably connected to one end of the transition section (102), and the other end of the rear shell (103) is detachably connected to the other end of the transition section (102); The receiving cavity (2) is provided in the front shell (101), the driving motor (5) is installed in the rear shell (103), the spraying hole (7) is provided on the front side wall of the front end of the front shell (101), and the central rod (6) penetrates through the front shell (101) and the transition section (102) and extends into the rear shell (103).

7. The high-speed liquid injection device for detection according to claim 6, characterized in that, A pressure balance hole (9) is formed in the rear side wall of the front housing (101). The pressure balance hole (9) communicates with the cavity of the accommodation chamber (2) located at the rear side of the piston (4), and the injection hole (7) communicates with the cavity of the accommodation chamber (2) located at the front side of the piston (4).

8. The high-speed liquid jetting device for detection liquid according to claim 6, wherein, It further includes a control board (10) installed in the rear housing (103), a bus slip ring (11) arranged on the control board (10), and a bus interface (12) arranged at the rear end of the central rod (6). The bus interface (12) is electrically connected to the bus slip ring (11), and the control board (10) is electrically connected to the control end of the drive motor (5) to supply power to the drive motor (5) and control its working state; A bus pin (104) for electrically connecting with the measurement probe (17) of the oil well flow probe is arranged on the front end face of the front housing (101). The bus pin (104) is electrically connected to the bus interface (12) through the central rod (6).

9. The high-speed liquid jetting device for detection liquid according to claim 8, characterized in that, It further includes an expansion interface (13) arranged at the rear end of the rear housing (101) and electrically connected to the control board (10), and a guiding cone head (105) detachably connected to the rear end of the rear housing (101).

10. An oil well flow probe, comprising a measurement probe tube (17) and a detection liquid injection device connected to the measurement probe tube (17), characterized in that, The detection liquid injection device is specifically the detection liquid high-speed injection device according to any one of claims 1-9.

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