Foamed cement generation device, generator, generation system and detection adjustment method

Abstract

The present application relates to a kind of foam cement generation device, generator, generation system and detection adjustment method, foam cement generation system, cement-based slurry assembly is communicated with foam cement generator by first pipeline, gas assembly is communicated with foam cement generator by second pipeline;Foam cement generator, first elbow, first connecting pipe, second elbow and second connecting pipe are sequentially connected, the end of second connecting pipe away from second elbow is connected with density flowmeter;Foam cement generation device, first group of jet orifice, second group of jet orifice and third group of jet orifice are set in jet unit;Detection adjustment process: generate cement-based slurry-generate foam cement slurry-detect the density of foam cement slurry;By setting first group of jet orifice, second group of jet orifice and third group of jet orifice, gas can be shot into cement-based slurry from multiple directions, greatly increase the gas-liquid contact area;In addition, by using density flowmeter, the real-time flow and density data can be accurately detected.

Description

Technical Field

[0001] This invention relates to the field of oil and gas cementing equipment technology, and in particular to a foam cement generating device, generator, generating system and detection and adjustment method. Background Technology

[0002] During cementing operations, some formations have low pressure bearing capacity and narrow safe operating pressure windows, posing a risk of pressure leakage during the cementing process. In high-permeability formations and shallow fractured formations, cement slurry loss is severe, compromising cementing quality. To prevent leakage during cementing, the cement slurry column flow rate is often reduced; however, this affects the displacement efficiency of the drilling fluid and carries the risk of annular pressure, impacting the safe production of oil and gas wells.

[0003] Foamed cement slurry, as a special low-density cement slurry, requires air bubbles to be uniformly and stably distributed throughout the slurry, effectively reducing the equivalent density of the slurry and preventing well leakage. Simultaneously, the presence of air bubbles in the slurry, utilizing the elasticity and compressibility of the gas, also effectively suppresses annular cross-flow. Furthermore, the cement stone formed by foamed cement slurry is a porous medium with good thermal insulation properties, which is beneficial for the development of thermal recovery wells.

[0004] Existing foamed cement generators mainly adopt a jet-type structure, and these generators have the following problems:

[0005] (1) The jet nozzle structure and jet direction are singular. If the jet orifice is too large, the gas will be too concentrated, and if the jet orifice is too small, the gas injection resistance will be large. After the cement-based slurry is mixed with the gas, a bubble equalization chamber is connected to break up large bubbles. Currently, spiral and baffle structures are commonly used. If the bubble equalization chamber is too short, the bubble breaking effect will be poor, and if the bubble equalization chamber is too long, the flow resistance will increase.

[0006] (2) Failure to monitor and adjust foam quality in real time. The initially formed foamed cement slurry needs to have its discharge pressure adjusted via a back pressure valve, and its density and uniformity need to be tested before it can be pumped into the wellbore. However, current equipment cannot perform real-time monitoring of the density and uniformity of multiphase fluids, and therefore cannot adjust the gas flow rate in real time to form foamed cement slurry that meets the density requirements. After injection into the wellbore, the pressure inside the wellbore becomes difficult to calculate. Summary of the Invention

[0007] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a foam cement generating device, generator, generating system and detection and adjustment method. Its advantages are that it can solve the technical problems of single jet nozzle structure and jet direction, and at the same time, it can monitor and adjust the foam quality in real time.

[0008] The above-mentioned objective of this invention is achieved through the following technical solution: In one aspect, this invention provides a foamed cement generating device, comprising a jetting unit and a mixing sleeve; one end of the jetting unit is inserted into the first end of the mixing sleeve, the jetting unit is threadedly connected to the mixing sleeve, the other end of the jetting unit is a gas inlet and extends outward along a first direction of the mixing sleeve, the second end of the mixing sleeve is a cement-based slurry inlet, and the third end of the mixing sleeve is an initial foamed cement outlet; the first end and the third end of the mixing sleeve are positioned opposite each other, and the first end and the second end of the mixing sleeve are perpendicular to each other; the jetting unit has a first set of jetting holes and a second set of... The mixing sleeve contains a first set of jet holes and a third set of jet holes. The first set of jet holes, the second set of jet holes, and the third set of jet holes are all located within the mixing chamber of the mixing sleeve and are connected to the mixing chamber of the mixing sleeve. Gas flows in through the gas inlet and is injected into the mixing chamber of the mixing sleeve from various angles through the first set of jet holes, the second set of jet holes, and the third set of jet holes. Cement-based slurry enters the mixing chamber of the mixing sleeve through the cement-based slurry inlet. The gas is encapsulated within the cement-based slurry to form initial foamed cement. The initial foamed cement flows along the first direction and flows out from the initial foamed cement outlet of the mixing sleeve.

[0009] Preferably, in the foamed cement generating device provided by the present invention, the jet unit includes a jet sleeve and a threaded tube. One end of the threaded tube is screwed into the first end of the mixing sleeve and sleeved on the first end of the jet sleeve. The threaded tube communicates with the jet sleeve, and the other end of the threaded tube is the gas inlet. The outer peripheral wall of the jet sleeve is provided with a first set of jet holes and a second set of jet holes, and the second end of the jet sleeve is provided with a third set of jet holes.

[0010] Preferably, in the foamed cement generating device provided by the present invention, the first set of jet holes includes multiple sets of horizontal radial holes, and the multiple sets of horizontal radial holes are spaced apart along the centerline direction of the jet sleeve.

[0011] Preferably, in the foamed cement generating device provided by the present invention, the second group of jet holes includes multiple rows of jet groups, which are spaced apart along the center line of the jet sleeve; each row of jet groups includes multiple air outlets, which are spaced apart along the circumference of the jet sleeve, and each row of jet groups is rotated by a preset angle about the center line of the jet sleeve so that the air outlets in each row are staggered.

[0012] Preferably, in the foamed cement generating device provided by the present invention, the jet sleeve includes a first cylinder and a second cylinder, one end of the first cylinder is connected to one end of the second cylinder, the first cylinder and the second cylinder are in communication, and the end of the first cylinder away from the second cylinder is inserted into the threaded pipe; the outer peripheral wall of the second cylinder is provided with the first set of jet holes and the second set of jet holes, and the end of the second cylinder away from the first cylinder is provided with the third set of jet holes.

[0013] Preferably, in the foamed cement generating device provided by the present invention, the mixing sleeve includes a first sleeve and a second sleeve. The centerline of the first sleeve is perpendicular to the centerline of the second sleeve. An installation hole is formed on the outer peripheral wall of the first sleeve, extending radially along the first sleeve and communicating with the cavity of the first sleeve. One end of the second sleeve is inserted into the installation hole, and the first sleeve communicates with the second sleeve. An internal thread adapted to the external thread of the threaded tube is formed on the inner peripheral wall near one end of the first sleeve. One end of the threaded tube is screwed into the first sleeve, and the threaded tube is threadedly connected to the first sleeve.

[0014] On one hand, the present invention provides a foamed cement generator, including the aforementioned foamed cement generating device, a first bend, a first connecting pipe, a second bend, a second connecting pipe, and a density flow meter. The first bend, the first connecting pipe, the second bend, and the second connecting pipe are sequentially connected to form a serpentine shape. The initial foamed cement outlet of the foamed cement generating device is connected to the end of the first bend away from the first connecting pipe, and the end of the second connecting pipe away from the second bend is connected to the density flow meter. A static mixer is provided inside the first connecting pipe and / or the second connecting pipe.

[0015] On one hand, the present invention provides a foamed cement generating system, including the aforementioned foamed cement generator, cement-based slurry component, gas component, unqualified foamed cement storage tank, qualified foamed cement slurry output component, and controller; the cement-based slurry component is connected to the foamed cement generator through a first pipe, the gas component is connected to the foamed cement generator through a second pipe, the qualified foamed cement slurry output component is connected to the foamed cement generator through a third pipe, and the unqualified foamed cement storage tank is connected to the third pipe through a fourth pipe; the foamed cement generator, the cement-based slurry component, the gas component, and the qualified foamed cement slurry output component are all communicatively connected to the controller.

[0016] Preferably, in the foamed cement generating system provided by the present invention, the qualified foamed cement slurry output component includes a pressure sensor, an electrically controlled valve, and a sampling control valve. The pressure sensor, the electrically controlled valve, and the sampling control valve are all disposed on the third pipeline. The fourth pipeline, the sampling control valve, the pressure sensor, and the electrically controlled valve are spaced apart along the extension direction of the third pipeline. The end of the third pipeline opposite to the foamed cement generator is the foamed cement slurry outlet. The pressure sensor and the electrically controlled valve are both communicatively connected to the controller.

[0017] On the other hand, the present invention provides a detection and adjustment method for the foamed cement generating system as described above, comprising the following steps:

[0018] Cement slurry and additives are mixed in a mixer to form a cement-based slurry;

[0019] The cement-based slurry and gas are mixed in the foamed cement generator to form foamed cement slurry;

[0020] The density of the foamed cement slurry generated by the foamed cement generator is detected by the density flow meter. The density control unit feeds back the detected information to the controller. The controller analyzes the received information and sends the adjusted gas flow value to the gas compressor so that the output density of the foamed cement slurry meets the set requirements.

[0021] In summary, the beneficial technical effects of this invention are as follows: The foam cement generating device, generator, generating system, and detection and adjustment method provided in this application, on the one hand, ensure that the foam cement is formed uniformly and stably through various forms such as shearing and internal turbulence by setting the jet sleeve, the first bend, the second bend, and the static mixer; on the other hand, by setting the first set of jet holes, the second set of jet holes, and the third set of jet holes, gas can be injected into the cement-based slurry from multiple directions, greatly increasing the gas-liquid contact area; the jet unit is threadedly connected to the mixing sleeve, thereby facilitating the replacement and cleaning of the jet unit; in addition, by using a density flow meter, real-time flow and density data can be accurately detected, and the gas flow rate is adjusted by the self-feedback system according to the density flow meter measurement results to meet the flow and density requirements of foam cement cementing. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall structure of the foamed cement generating device provided in the first embodiment of the present invention.

[0023] Figure 2 This is a schematic diagram of the jet sleeve in the foamed cement generating device provided in the first embodiment of the present invention.

[0024] Figure 3This is a diagram showing the distribution of pores in the foamed cement generating device provided in the first embodiment of the present invention.

[0025] Figure 4 This is a schematic diagram of the overall structure of the foamed cement generator provided in the second embodiment of the present invention.

[0026] Figure 5 This is a schematic diagram of the overall structure of the foamed cement generating system provided in the third embodiment of the present invention.

[0027] Figure 6 This is a flowchart of the detection and adjustment method for the foamed cement generation system provided in the fourth embodiment of the present invention.

[0028] In the diagram, 1. Foamed cement generating system; 10. Foamed cement generator; 11. Foamed cement generating device; 111. Jet unit; 1111. Jet sleeve; 1112. First cylinder; 1113. Second cylinder; 1114. Threaded pipe; 1115. Gas inlet; 112. Mixing sleeve; 1121. First sleeve; 1123. Initial foamed cement outlet; 1124. Second sleeve; 1125. Cement slurry inlet; 1126. Cement slurry outlet; 1127. Mixing chamber; 12. First bend; 13. First connecting pipe; 14. Second... 15. Bend; 508. Second connecting pipe; 17. Density flow meter; 18. Static mixer; 20. Support; 501. Cement-based slurry assembly; 502. Density meter; 503. Pressure gauge; 504. Flow meter; 505. First opening control unit; 30. Gas assembly; 40. Unqualified foamed cement storage tank; 50. Qualified foamed cement slurry output assembly; 506. Pressure sensor; 505. Pressure control unit; 507. Density control unit; 509. Second opening control unit; 60. First pipeline; 70. Second pipeline; 80. Third pipeline; 90. Fourth pipeline. Detailed Implementation

[0029] The present invention will be further described in detail below with reference to the accompanying drawings.

[0030] First embodiment:

[0031] Reference Figures 1 to 3The first embodiment of the present invention discloses a foamed cement generating device 11, comprising a jetting unit 111 and a mixing sleeve 112; one end of the jetting unit 111 is inserted into the first end of the mixing sleeve 112, and the jetting unit 111 and the mixing sleeve 112 are threadedly connected; the other end of the jetting unit 111 is a gas inlet 1115, extending outward along a first direction of the mixing sleeve 112; the second end of the mixing sleeve 112 is a cement-based slurry inlet 1125. The third end of 112 is the initial foamed cement outlet 1123. The first end of the mixing sleeve 112 is positioned opposite to the third end of the mixing sleeve 112, and the first end of the mixing sleeve 112 is perpendicular to the second end of the mixing sleeve 112. The jet unit 111 is provided with a first set of jet holes, a second set of jet holes, and a third set of jet holes 307. The first set of jet holes, the second set of jet holes, and the third set of jet holes 307 are all located within the mixing chamber 1127 of the mixing sleeve 112. The jet orifice, the second set of jet orifices, and the third set of jet orifices 307 are all connected to the mixing chamber 1127 of the mixing sleeve 112. Gas flows in through the gas inlet 1115 and is injected into the mixing chamber 1127 of the mixing sleeve 112 from various angles through the first set of jet orifices, the second set of jet orifices, and the third set of jet orifices 307. Cement-based slurry enters the mixing chamber 1127 of the mixing sleeve 112 through the cement-based slurry inlet 1125. Gas is encased in the cement-based slurry to form initial foamed cement. The initial foamed cement flows along the first direction and flows out from the initial foamed cement outlet 1123 of the mixing sleeve 112. On the one hand, by setting the first set of jet orifices, the second set of jet orifices, and the third set of jet orifices 307, gas is injected into the mixing chamber 1127 of the mixing sleeve 112 from various directions, increasing the contact area between gas and liquid. On the other hand, by setting the jet unit 111 to be threadedly connected to the mixing sleeve 112, it is convenient to replace and maintain the jet unit 111.

[0032] It should be noted that, with Figure 1 Taking the orientation shown as an example, the first direction of the mixed sleeve 112 is the direction of the horizontal center line of the mixed sleeve 112.

[0033] The cement-based slurry consists of cement slurry and admixtures, which are mixed in advance before entering the foamed cement generating device 11. The admixtures are foaming agents and foam stabilizers.

[0034] In this embodiment, nitrogen is used as the gas. During use, a gas cylinder group or liquid nitrogen truck can be used as the gas source, and the gas pipeline pressure and discharge rate can be adjusted.

[0035] Among them, the mixing sleeve 112 is a three-way pipe. During use, cement-based slurry enters through the cement-based slurry inlet 1125 and flows into the mixing chamber 1127 through the cement-based slurry outlet 1126. The cement-based slurry outlet 1126 has a certain degree of eccentricity.

[0036] The first group of jet holes, the second group of jet holes, and the third group of jet holes 307 are arranged at intervals along the first direction. The first group of jet holes is distributed at the intersection with the cement slurry outlet 1126. That is, the first group of jet holes is set perpendicular to and in the direction of the liquid flow. The first group of jet holes mixes with the cement slurry that first flows into the mixing chamber 1127, but the gas does not directly collide with the cement slurry flow. The second group of jet holes is set on the outer peripheral wall of the jet unit 111 after the cement slurry outlet 1126. A narrow annular space is formed between the jet unit 111 and the inner peripheral wall of the mixing chamber 1127. The third group of jet holes 307 is set at the end of the jet unit 111.

[0037] The working process of the foamed cement generating device 11 provided in this embodiment is as follows: gas flows in through the gas inlet 1115 and is injected into the mixing chamber 1127 of the mixing sleeve 112 from various angles through the first set of jet holes, the second set of jet holes, and the third set of jet holes 307. Cement slurry enters through the cement slurry inlet 1125 and flows into the mixing chamber 1127 through the cement slurry outlet 1126. Since the gas inlet 1115 and the cement slurry inlet 1125 are perpendicular, the cement slurry outlet 1126 is eccentric, which allows the cement slurry to enter the mixing chamber 1127 and spiral along the inner wall of the mixing chamber 1127, which plays a role in shearing and stirring the gas, and wrapping the gas in the cement slurry to form initial foamed cement. The initial foamed cement flows along the first direction and flows out from the initial foamed cement outlet 1123 of the mixing sleeve 112.

[0038] Furthermore, in this embodiment, the jet unit 111 includes a jet sleeve 1111 and a threaded tube 1114. One end of the threaded tube 1114 is screwed into the first end of the mixing sleeve 112 and sleeved on the first end of the jet sleeve 1111. The threaded tube 1114 is connected to the jet sleeve 1111, and the other end of the threaded tube 1114 is a gas inlet 1115. A first set of jet holes and a second set of jet holes are opened on the outer peripheral wall of the jet sleeve, and a third set of jet holes 307 is opened at the second end of the jet sleeve.

[0039] Specifically, the centerline of the jet sleeve 1111 and the centerline of the threaded tube 1114 are both set parallel to the first direction. In some feasible embodiments, the centerline of the jet sleeve 1111 and the centerline of the threaded tube 1114 are set collinearly.

[0040] The threaded tube 1114 has a gas inlet 1115 at one end away from the jet sleeve 1111 and extends outward along the first direction. During use, gas flows into the threaded tube 1114 through the gas inlet 1115 and into the jet sleeve 1111 through the threaded tube 1114. Then, the gas flows into the mixing chamber 1127 from various directions through the first set of jet holes, the second set of jet holes, and the third set of jet holes 307.

[0041] Specifically, the second set of jet holes is set on the outer peripheral wall of the jet sleeve 1111 after the cement slurry outlet 1126, where a narrow annular space is formed between the jet sleeve 1111 and the inner peripheral wall of the mixing chamber 1127.

[0042] Continue to refer to Figure 2 and Figure 3 In this embodiment, the first set of jet holes includes multiple sets of horizontal radial holes 302, which are spaced apart along the center line of the jet sleeve 1111.

[0043] For example, the first set of jet orifices may include four sets of horizontal radial orifices 302. Of course, the first set of jet orifices may also include five or six sets of horizontal radial orifices 302. In the possible implementation where the first set of jet orifices includes four sets of horizontal radial orifices 302, the four sets of horizontal radial orifices 302 are spaced apart along the centerline of the jet sleeve 1111. The horizontal radial orifices 302 mix with the first incoming cement-based slurry, and the gas flowing out of the horizontal radial orifices 302 does not counteract the incoming cement-based slurry.

[0044] Furthermore, in this embodiment, the second set of jet holes includes multiple rows of jet groups, which are spaced apart along the center line of the jet sleeve 1111; each row of jet groups includes multiple air outlets, which are spaced apart along the circumference of the jet sleeve 1111; each row of jet groups is rotated by a preset angle about the center line of the jet sleeve 1111 so that the air outlets in each row are staggered.

[0045] Specifically, a certain number of air outlets are provided on the circumferential cross-section of the jet sleeve 1111 and are distributed and arranged along the circumference of the jet sleeve 1111. The air outlets on adjacent cross-sections are arranged in a spiral manner with a preset angle rotated around the center line of the jet sleeve 1111 as the axis.

[0046] For example, the second set of jet orifices may include four jet groups (303, 304, 305, 306), or of course, the second set of jet orifices may include five or six jet groups.

[0047] In this embodiment, the third set of jet holes 307 is disposed at one end of the jet sleeve 1111 away from the threaded tube 1114, and the third set of jet holes 307 is consistent with the downstream flow direction.

[0048] The distribution of the first group of jet holes, the second group of jet holes, and the third group of jet holes 307 maximizes the gas-liquid contact area, while ensuring that a large gas displacement can be achieved under small jet holes to meet the foaming requirements of foamed cement.

[0049] It should be noted that the size, number, and distribution of the holes in the first group of jet holes, the second group of jet holes, and the third group of jet holes 307 can be adapted according to the requirements.

[0050] Furthermore, in this embodiment, the jet sleeve 1111 includes a first cylinder 1112 and a second cylinder 1113. One end of the first cylinder 1112 is connected to one end of the second cylinder 1113, and the first cylinder 1112 and the second cylinder 1113 are in communication. The end of the first cylinder 1112 away from the second cylinder 1113 is inserted into the threaded tube 1114. A first set of jet holes and a second set of jet holes are opened on the outer peripheral wall of the second cylinder 1113, and a third set of jet holes 307 is opened on the end of the second cylinder 1113 away from the first cylinder 1112.

[0051] Specifically, the center line of the first cylinder 1112 is set parallel to the center line of the second cylinder 1113. In some feasible ways, the center line of the first cylinder 1112 is set collinear with the center line of the second cylinder 1113.

[0052] It should be noted that the outer diameter of the first cylinder 1112 is larger than the outer diameter of the second cylinder 1113.

[0053] Continue to refer to Figure 1 In this embodiment, the hybrid sleeve 112 includes a first sleeve 1121 and a second sleeve 1124. The centerline of the first sleeve 1121 is perpendicular to the centerline of the second sleeve 1124. An installation hole is provided on the outer peripheral wall of the first sleeve 1121, which extends radially along the first sleeve 1121 and communicates with the cavity of the first sleeve 1121. One end of the second sleeve 1124 is inserted into the installation hole, and the first sleeve 1121 and the second sleeve 1124 are in communication. An internal thread that matches the external thread of the threaded tube 1114 is provided on the inner peripheral wall near the end of the first sleeve 1121. One end of the threaded tube 1114 is screwed into the first sleeve 1121, and the threaded tube 1114 is threadedly connected to the first sleeve 1121.

[0054] It should be noted that the cavity of the first sleeve 1121 is the mixing cavity 1127 of the mixing sleeve 112, the end of the second sleeve 1124 inserted into the installation hole is the cement slurry outlet 1126, and the end of the second sleeve 1124 away from the first sleeve 1121 is the cement slurry inlet 1125.

[0055] Specifically, the centerline of the first sleeve 1121 is set parallel to the centerline of the jet sleeve 1111. In some feasible embodiments, the centerline of the first sleeve 1121 is set collinear with the centerline of the jet sleeve 1111.

[0056] One end of the threaded pipe 1114 is screwed into the first sleeve 1121 and sleeved on the end of the first cylinder 1112 away from the second cylinder 1113. The end of the first sleeve 1121 away from the threaded pipe 1114 is the initial foamed cement outlet 1123.

[0057] Second embodiment:

[0058] Continue to refer to Figure 4 The second embodiment provides a foamed cement generator 10, including a foamed cement generating device 11 provided in the first embodiment, a first bend 12, a first connecting pipe 13, a second bend 14, a second connecting pipe 15, and a density flow meter 508. The first bend 12, the first connecting pipe 13, the second bend 14, and the second connecting pipe 15 are connected in sequence to form a serpentine shape. The initial foamed cement outlet 1123 of the foamed cement generating device 11 is connected to the end of the first bend 12 away from the first connecting pipe 13, and the end of the second connecting pipe 15 away from the second bend 14 is connected to the density flow meter 508. A static mixer 17 is provided in the first connecting pipe 13 and / or the second connecting pipe 15. By setting a serpentine flow channel to continuously change the flow direction, large air bubbles are broken up under high turbulence intensity, thereby improving the stability of the foamed cement.

[0059] Specifically, the initial foam cement outlet 1123 (i.e. the third end) of the mixing sleeve 112 in the foam cement generating device 11 is connected to the end of the first bend 12 away from the first connecting pipe 13 via a nut. The connection between the first bend 12 and the first connecting pipe 13, the connection between the first connecting pipe 13 and the second bend 14, and the connection between the second bend 14 and the second connecting pipe 15 are all connected by a nut.

[0060] For example, the static mixer 17 is an SK static mixer 17. Of course, other models of static mixer 17 can also be used, as long as they can make the foamed cement uniformly mixed.

[0061] During use, the initial foamed cement slurry flows out through the initial foamed cement outlet 1123 and then enters the static mixer 17 in the first connecting pipe 13 via the first bend 12. In the static mixer 17, the foamed cement is continuously cut by the interlaced left- and right-twisting spiral blades, which exponentially increases the uniformity of the foamed cement mixture and further enhances its turbulence. If necessary, turbulence-enhancing elements can be added at the second connecting pipe 15 to ensure the stability and uniformity of the foamed cement. These turbulence-enhancing elements refer to components such as baffles and coils placed in the mixer to improve the mixing degree.

[0062] For example, the density flow meter 508 can be a straight-tube density meter that uses a vibrating tube to measure density, suitable for multiphase flow. Of course, density can also be measured using gas tracer detection, X-ray density meter, or volumetric weighing density meter, depending on the gas content.

[0063] In this embodiment, the foam cement generator 10 is placed vertically to make full use of the three-dimensional space, and the foam cement generator 10 is fixed by the bracket 18.

[0064] Specifically, the support 18 is a rectangular frame. To improve the strength of the rectangular frame, reinforcing rods are installed inside the rectangular frame. The support 18 is connected to the foam cement generator 10 by bolts.

[0065] In this embodiment, multiple resistance probes are set in the static mixer 17. The multiple resistance probes are spaced apart along the center line of the first connecting pipe 13 to measure the resistivity at different locations and use the signals to determine the uniformity and stability of the foamed cement slurry.

[0066] Third embodiment:

[0067] Continue to refer to Figure 5 The third embodiment provides a foamed cement generating system 1, including a foamed cement generator 10, a cement-based slurry component 20, a gas component 30, a substandard foamed cement storage tank 40, a qualified foamed cement slurry output component 50, and a controller PLC, as provided in the second embodiment. The cement-based slurry component 20 is connected to the foamed cement generator 10 through a first pipe 60, the gas component 30 is connected to the foamed cement generator 10 through a second pipe 70, the qualified foamed cement slurry output component 50 is connected to the foamed cement generator 10 through a third pipe 80, and the substandard foamed cement storage tank 40 is connected to the third pipe 80 through a fourth pipe 90. The foamed cement generator 10, the cement-based slurry component 20, the gas component 30, and the qualified foamed cement slurry output component 50 are all communicatively connected to the controller PLC.

[0068] During use, the cement slurry component 20 is used to mix cement slurry with admixtures to form cement slurry. The cement slurry enters the mixing chamber 1127 through the first pipe 60 foam cement generator 11 and the cement slurry inlet 1125 of the foam cement generator 11. The gas component 30 introduces gas into the mixing chamber 1127 through the second pipe 70 foam cement generator 11 and the gas inlet 1115 of the foam cement generator 11.

[0069] The foamed cement generating system 1 provided in this embodiment is used as follows: cement slurry flows into the foamed cement generator 10 through the first pipe 60, and gas enters the foamed cement generator 10 through the second pipe 70. The cement slurry and gas mix in the foamed cement generator 10 to form foamed cement slurry. The density of the foamed cement slurry is measured by the density flow meter 508. If the density measurement meets the requirements, the foamed cement will be sampled under pressure through the third pipe 80. If the density measurement does not meet the requirements, the foamed cement slurry will enter the unqualified foamed cement storage tank 40 through the fourth pipe 90.

[0070] Furthermore, in this embodiment, the qualified foamed cement slurry output component 50 includes a pressure sensor 506, an electrically controlled valve, and a sampling control valve. The pressure sensor 506, the electrically controlled valve, and the sampling control valve are all installed on the third pipe 80. The fourth pipe 90, the sampling control valve, the pressure sensor 506, and the electrically controlled valve are spaced apart along the extension direction of the third pipe 80. The end of the third pipe 80 away from the foamed cement generator 10 is the foamed cement slurry outlet. The pressure sensor and the electrically controlled valve are both connected to the controller PLC.

[0071] During use, the density flow meter 508 is used to measure the density of the foamed cement slurry and, based on the density measurement result, sends a feedback signal to the controller PLC. The controller PLC controls the gas component 30 to increase or decrease the gas flow rate and adjusts the outlet pressure of the foamed cement slurry through the pressure control unit 505 until the density meets the requirements.

[0072] Furthermore, in this embodiment, the cement-based slurry assembly 20 includes a cement slurry storage tank, a slurry pump, a mixer, a densitometer 501, a pressure gauge 502, a flow meter 503, an additive storage tank, and a metering pump. The outlet of the cement slurry storage tank is connected to the input end of the slurry pump through a first pipeline, and the output end of the slurry pump is connected to the mixer through a second pipeline. The mixer is connected to the foamed cement generator 10 through a first pipe 60, and the cement slurry storage tank is connected to the first pipe 60 through a return pipe. The densitometer 501, pressure gauge 502, and flow meter 503 are all installed on the first pipe 60, and are located between the mixer and the return pipe. The densitometer 501, pressure gauge 502, and flow meter 503 are arranged at intervals from left to right.

[0073] Control valves are installed on both the return slurry pipe and the first pipe 60. The additive storage tank is connected to the metering pump through the third pipeline, and the metering pump is connected to the mixer through the fourth pipeline. The mud pump, density meter 501, pressure meter 502, flow meter 503 and metering pump are all connected to the controller PLC.

[0074] During use, the cement slurry in the cement slurry storage tank is pumped into the mixer by a mud pump, and the additives in the additive storage tank are pumped into the mixer by a metering pump. The cement slurry and the additives are mixed in the mixer to form a cement-based slurry and maintain a certain density and pressure. The density of the cement-based slurry is measured by a densitometer 501, the pressure is measured by a pressure gauge 502, and the flow rate is measured by a flow meter 503.

[0075] Furthermore, in this embodiment, the gas assembly 30 includes a gas compression pump and an electric control valve. The gas compression pump is connected to the electric control valve through a connecting pipe, and the electric control valve is connected to the foam cement generator 10 through a second pipe 70. Both the gas compression pump and the electric control valve are communicatively connected to the controller.

[0076] During operation, the specified foamed cement discharge rate and density at discharge pressure are input into the PLC controller. The PLC controller calculates according to the program and provides an initial value for the mud pump, metering pump, and gas compressor pump. The mud pump opening is adjusted by the first opening control unit 504 to control the cement slurry flow rate. The additive flow rate is controlled by the metering pump. The gas flow rate is controlled by adjusting the opening of the electric control valve by the second opening control unit 509. After the foamed cement slurry is generated by mixing in the foamed cement generator 10, the density flow meter 508 will detect the density of the foamed cement slurry. The density control unit 507 feeds back to the PLC controller, which then adjusts the gas flow rate and feeds it back to the gas compressor pump so that the output density of the foamed cement meets the set requirements.

[0077] Fourth embodiment:

[0078] Reference Figure 6 The fourth embodiment provides a detection and adjustment method for the foamed cement generating system 1 as provided in the third embodiment, including the following steps:

[0079] S101. Cement slurry and additives are mixed in a mixer to form cement-based slurry.

[0080] Specifically, the specified foam cement discharge rate and density at discharge pressure are input into the PLC controller; the PLC controller calculates according to the program and provides an initial value for the mud pump, metering pump and gas compression pump; the mud pump opening is adjusted through the first opening control unit 504 to control the cement slurry flow rate; and the additive flow rate is controlled through the metering pump.

[0081] The cement slurry in the cement slurry storage tank is fed into the mixer by a mud pump, and the additives in the additive storage tank are fed into the mixer by a metering pump. The cement slurry and the additives are mixed in the mixer to form a cement-based slurry and maintain a certain density and pressure. The density of the cement-based slurry is measured by a densitometer 501, the pressure is measured by a pressure gauge 502, and the flow rate is measured by a flow meter 503.

[0082] S102, Cement-based slurry and gas are mixed in foam cement generator 10 to form foam cement slurry.

[0083] Specifically, the opening of the electric control valve is adjusted by the second opening control unit 509 to control the gas flow rate; the gas and cement-based slurry are mixed by the foam cement generator 10 to produce foam cement slurry.

[0084] S103. The density of the foamed cement produced by the foamed cement generator 10 is detected by the density flow meter 508. The density control unit 507 feeds back the detected information to the controller. The controller analyzes the received information and sends the adjusted gas flow value to the gas compressor so that the output density of the foamed cement slurry meets the set requirements.

[0085] Specifically, the controller analyzes the received information and sends the adjusted gas flow rate value to the gas compressor to increase or decrease the gas flow rate. The outlet pressure of the foamed cement slurry is adjusted by the pressure control unit 505 until the density meets the requirements.

[0086] As can be seen, the foam cement generating device 11, generator, generating system, and detection and adjustment method provided in this application, on the one hand, ensure that the foam cement is formed into uniform and stable foam cement through various forms such as shearing and internal turbulence by setting the jet sleeve 1111, the first bend 12, the second bend 14, and the static mixer 17; on the other hand, by setting the first set of jet holes, the second set of jet holes, and the third set of jet holes 307, gas can be injected into the cement-based slurry from multiple directions, greatly increasing the gas-liquid contact area; the jet unit 111 is threadedly connected to the mixing sleeve 112, thereby facilitating the replacement and cleaning of the jet unit 111; in addition, by using the density flow meter 508, real-time flow and density data can be accurately detected, and the gas flow rate is adjusted by the self-feedback system according to the measurement results of the density flow meter 508 to meet the flow and density requirements of foam cement cementing.

[0087] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0088] Finally, it should be noted that the above embodiments are merely examples for clearly illustrating the present invention and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A foamed cement generating device, characterized by: Includes jet unit and mixing sleeve; One end of the jetting unit is inserted into the first end of the mixing sleeve, and the jetting unit is threadedly connected to the mixing sleeve. The other end of the jetting unit is a gas inlet and extends outward along the first direction of the mixing sleeve. The second end of the mixing sleeve is a cement-based slurry inlet, and the third end of the mixing sleeve is an initial foamed cement outlet. The first end and the third end of the mixing sleeve are positioned opposite each other, and the first end and the second end of the mixing sleeve are positioned perpendicularly to each other. The jet unit is provided with a first group of jet holes, a second group of jet holes and a third group of jet holes. The first group of jet holes, the second group of jet holes and the third group of jet holes are all located in the mixing cavity of the mixing sleeve. The first group of jet holes, the second group of jet holes and the third group of jet holes are all connected to the mixing cavity of the mixing sleeve. Gas flows in through the gas inlet and is injected into the mixing chamber of the mixing sleeve from various angles through the first set of jet holes, the second set of jet holes, and the third set of jet holes. Cement-based slurry enters the mixing chamber of the mixing sleeve through the cement-based slurry inlet. The gas is encapsulated in the cement-based slurry to form initial foamed cement. The initial foamed cement flows along the first direction and flows out from the initial foamed cement outlet of the mixing sleeve. The jet unit includes a jet sleeve and a threaded tube. One end of the threaded tube is screwed into the first end of the mixing sleeve and sleeved on the first end of the jet sleeve. The threaded tube is connected to the jet sleeve, and the other end of the threaded tube is the gas inlet. The outer peripheral wall of the jet sleeve is provided with the first set of jet holes and the second set of jet holes, and the second end of the jet sleeve is provided with the third set of jet holes.

2. The foamed cement generating device according to claim 1, characterized in that: The first set of jet holes includes multiple sets of horizontal radial holes, which are spaced apart along the centerline of the jet sleeve.

3. The foamed cement generating device according to claim 2, characterized in that: The second group of jet holes includes multiple rows of jet groups, which are spaced apart along the centerline of the jet sleeve; Each column of the jet assembly includes multiple air outlets, which are spaced apart circumferentially along the jet sleeve. Each column of the jet assembly rotates by a preset angle about the center line of the jet sleeve so that the air outlets in each column are staggered.

4. The foamed cement generating device according to claim 3, characterized in that: The jet sleeve includes a first cylinder and a second cylinder. One end of the first cylinder is connected to one end of the second cylinder. The first cylinder and the second cylinder are in communication. The end of the first cylinder away from the second cylinder is inserted into the threaded tube. The second cylinder has the first set of jet holes and the second set of jet holes on its outer peripheral wall, and the second cylinder has the third set of jet holes at the end opposite to the first cylinder.

5. The foamed cement generating device according to claim 1, characterized in that: The hybrid sleeve includes a first sleeve and a second sleeve. The centerline of the first sleeve is perpendicular to the centerline of the second sleeve. An installation hole is provided on the outer peripheral wall of the first sleeve. The installation hole extends radially along the first sleeve and communicates with the cavity of the first sleeve. One end of the second sleeve is inserted into the installation hole. The first sleeve and the second sleeve communicate with each other. An internal thread adapted to the external thread of the threaded tube is formed on the inner circumferential wall near one end of the first sleeve. One end of the threaded tube is screwed into the first sleeve, and the threaded tube is threadedly connected to the first sleeve.

6. A foamed cement generator, characterized in that: The device includes a foamed cement generating device as described in any one of claims 1 to 5, a first bend, a first connecting pipe, a second bend, a second connecting pipe, and a density flow meter. The first bend, the first connecting pipe, the second bend, and the second connecting pipe are connected in sequence to form a serpentine shape. The initial foamed cement outlet of the foamed cement generating device is connected to the end of the first bend away from the first connecting pipe, and the end of the second connecting pipe away from the second bend is connected to the density flow meter. A static mixer is provided inside the first connecting pipe and / or the second connecting pipe.

7. A foamed cement generating system, characterized in that: The system includes the foamed cement generator, cement-based slurry assembly, gas assembly, unqualified foamed cement storage tank, qualified foamed cement slurry output assembly, and controller as described in claim 6; the cement-based slurry assembly is connected to the foamed cement generator via a first pipe, the gas assembly is connected to the foamed cement generator via a second pipe, the qualified foamed cement slurry output assembly is connected to the foamed cement generator via a third pipe, and the unqualified foamed cement storage tank is connected to the third pipe via a fourth pipe; The foamed cement generator, the cement-based slurry assembly, the gas assembly, and the qualified foamed cement slurry output assembly are all communicatively connected to the controller.

8. The foamed cement generating system according to claim 7, characterized in that: The qualified foamed cement slurry output component includes a pressure sensor, an electric control valve, and a sampling control valve. The pressure sensor, the electric control valve, and the sampling control valve are all installed on the third pipeline. The fourth pipeline, the sampling control valve, the pressure sensor, and the electric control valve are spaced apart along the extension direction of the third pipeline. The end of the third pipeline away from the foamed cement generator is the foamed cement slurry outlet. Both the pressure sensor and the electronically controlled valve are communicatively connected to the controller.

9. A method for detecting and adjusting a foamed cement generating system as described in any one of claims 7 to 8, characterized in that: Includes the following steps: Cement slurry and additives are mixed in a mixer to form a cement-based slurry; The cement-based slurry and gas are mixed in the foamed cement generator to form foamed cement slurry; The density of the foamed cement slurry generated by the foamed cement generator is detected by the density flow meter. The density control unit feeds back the detected information to the controller. The controller analyzes the received information and sends the adjusted gas flow value to the gas compressor so that the output density of the foamed cement slurry meets the set requirements.

Images