Cement slurry dynamic water invasion resistance evaluation device and method for cementing

Abstract

The application belongs to the technical field of indoor test of oil well completion, and particularly provides a cementing cement slurry dynamic water invasion resistance evaluation device, which comprises an electric conductivity tester, a PH tester, a controller, a kettle cylinder, a magnetic drive assembly, a metering pump, a servo motor, a cement tank and a water tank, the cement tank is connected in the kettle cylinder, the power output end of the servo motor is connected with the cement tank through the magnetic drive assembly, and the cement tank is sleeved with the kettle cylinder; one way of the water tank is connected with the kettle cylinder, and the other way of the water tank is connected with the kettle cylinder through the metering pump, the PH value probe of the PH tester and the electric conductivity probe of the electric conductivity tester are both connected with the kettle cylinder, and the water tank is provided with water; the controller is electrically connected with the electric conductivity tester, the PH tester, the magnetic drive assembly, the metering pump, the servo motor and the water tank, and the problem that the existing cement slurry dynamic water invasion resistance cannot be qualitatively and quantitatively evaluated is solved, and the cement slurry invasion resistance performance evaluation under the dynamic pressure condition is realized.

Description

Technical Field

[0001] This invention belongs to the field of indoor testing technology for oil well completion, specifically relating to an evaluation device and method for evaluating the resistance of cement slurry to dynamic water intrusion. Background Technology

[0002] Currently, Changqing Oilfield is in the mid-to-late stage of development. To improve recovery rates, adjustment wells have been deployed in older blocks. Through long-term layered development, secondary rolling development, multi-level high-pressure water injection, and high-intensity fracturing, the old oilfield has formed a complex pressure system with coexisting high-pressure, normal-pressure, and low-pressure layers. As the well spacing of development wells gradually shortens, formations at the same or adjacent oil-bearing levels are prone to cross-contamination. Simultaneous drilling, fracturing, water injection, and oil production in the same block lead to disorder in the target formation pressure system. During cementing and in the post-cementation phase, formation fluids remain in a seepage state, severely affecting the cementing quality of the target formation. Therefore, there is an urgent need to develop water-resistant cement slurries and evaluation devices for cementing under dynamic pressure systems to meet the cementing requirements under water-dampened conditions. In recent years, relevant research institutions in the industry both domestically and internationally have conducted research on water-resistant cement slurry systems, but no evaluation instruments for the anti-intrusion and anti-erosion properties of cement slurries under dynamic pressure conditions have been developed, and a unified evaluation standard and method have not yet been established. There is an urgent need to develop an instrument that can evaluate the erosion resistance of cement slurry under conditions of water layer disturbance, so as to ensure cementing quality and construction safety.

[0003] The invention patent number CN107167499B discloses an evaluation device and method for the water intrusion resistance of cement slurry during the setting process. It is a method to evaluate the water intrusion resistance of cement slurry by measuring the electrical conductivity of water after water erosion of cement slurry.

[0004] The invention patent number CN110376360A discloses a device for testing the water-resistant properties of cement slurry, which is a method for calculating the cementitious strength by measuring the viscosity of cement slurry after it has been eroded by water.

[0005] The invention patent number CN111691874A discloses a device and method for evaluating the waterproofing effect of cement slurry. It is a method that simulates formation water flowing at a constant flow rate through a simulated wellbore, cement slurry, and the contact area between the cement slurry and the simulated wellbore under simulated formation temperature and pressure conditions. After reaching the curing age (e.g., 24 hours), the pressure of the contact area between the simulated wellbore and the cement stone is tested by a pressure machine, and the bonding strength of the cement stone is finally calculated.

[0006] The invention patent number CN112377146A discloses a device and method for simulating formation water seepage and water intrusion into cement slurry in wells. By pressurizing the simulated formation water, the formation water passes through the simulated core, cement slurry, and simulated core under pressure difference, and then enters the filtrate collection bottle. After the cement slurry solidifies into cement stone and reaches the curing age (e.g., 24 hours), the method tests the cross-contamination pressure at the interface between the simulated core and the cement stone.

[0007] While the aforementioned patent documents simulate some downhole environments and evaluation methods, they cannot accurately simulate environmental parameters such as downhole pressure differences and water seepage velocity. They differ significantly from actual downhole environments and cannot accurately reflect the water erosion resistance of cement slurry under well conditions. Summary of the Invention

[0008] The purpose of the evaluation device and method for evaluating the resistance to dynamic water intrusion of cement slurry provided by the present invention is to overcome the problem that the existing technology cannot qualitatively and quantitatively evaluate the resistance to dynamic water intrusion of cement slurry.

[0009] To address this, the present invention provides an evaluation device for evaluating the resistance of cement slurry to dynamic water intrusion, comprising a conductivity meter, a pH meter, a controller, a vessel, a magnetic drive assembly, a metering pump, a servo motor, a cement tank, and a water tank. The cement tank is connected inside the vessel, and the power output end of the servo motor is connected to the cement tank through the magnetic drive assembly. The vessel is outer-mounted around the cement tank. One path of the water tank is connected to the vessel, and the other path of the water tank is connected to the vessel through the metering pump. The pH probe of the pH meter and the conductivity probe of the conductivity meter are both connected to the vessel. The water tank contains water. The controller is electrically connected to the conductivity meter, the pH meter, the magnetic drive assembly, the metering pump, the servo motor, and the water tank.

[0010] Preferably, the magnetic drive assembly includes an inner magnetic assembly and an outer magnetic assembly, with the power output end of the servo motor connected to the outer magnetic assembly, and the inner magnetic assembly nested inside the outer magnetic assembly.

[0011] Preferably, the cement silo includes a mixing body, an upper cover, a lower cover, a paddle, a cup shaft, a simulated mesh welding frame one, a pressure cap, a screw plug, a simulated mesh welding frame two, and a cover one. The upper cover, cover one, pressure cap, paddle, and lower cover are sequentially fitted onto the outside of the cup shaft from top to bottom. The mixing body is connected between the upper cover and the lower cover, and cover one, pressure cap, and paddle are all located within the mixing body. Simulated mesh welding frame two and simulated mesh welding frame one are sequentially connected from top to bottom within the mixing body between the pressure cap and the lower cover. Simulated mesh welding frame two and simulated mesh welding frame one are both provided with simulated geological fracture mesh. A screw plug is fitted onto the lower end of the lower cover.

[0012] Preferably, the cement hopper further includes a cup platform, the outer side of the screw plug is sleeved on the cup platform and the upper part of the cup platform is connected to the lower part of the lower cover, and the middle part of the cup platform is connected to the upper end of the inner magnetic assembly.

[0013] Preferably, the vessel cylinder includes a vessel body, a sealing rod, a vessel lid, and a sealing joint. The upper part of the cup shaft is connected to the vessel lid through the sealing rod, the vessel lid is connected to the upper end of the vessel body, and the upper end of the sealing rod is connected to the sealing joint.

[0014] Preferably, the stirring body has multiple through holes spaced at equal intervals in the circumferential direction.

[0015] Preferably, the stirring element does not come into contact with the vessel body.

[0016] Preferably, the vessel body includes a side plate and a bottom plate. The side plate is cylindrical, and the bottom surface of the side plate is connected to the bottom plate. A through hole II is provided in the middle of the bottom plate, and the upper part of the inner magnetic component is connected to the through hole II.

[0017] Preferably, pressure regulating valves are provided between the conductivity tester and the vessel cylinder, and between the metering pump and the vessel cylinder.

[0018] An evaluation method based on the aforementioned cement slurry resistance to dynamic water intrusion evaluation device includes the following steps:

[0019] 1) Fill the cement slurry with the prepared cement slurry, place the cement slurry-filled ...

[0020] 2) Connect the pH probe of the pH tester and the conductivity probe of the conductivity tester to the simulated formation water in the vessel, and test and record the pH and conductivity values ​​of the simulated formation water.

[0021] 3) Start the metering pump to allow the simulated formation water in the vessel to circulate with the simulated formation water in the tank through the pH probe and conductivity probe. After the pH and conductivity tester values ​​stabilize, check and record the pH and conductivity values.

[0022] 4) Start the servo motor at speed 1. The servo motor drives the outer magnetic component to rotate, which in turn drives the inner magnetic component to rotate. The inner magnetic component drives the stirring body to rotate through the cup platform. The impeller is connected to the vessel lid through the cup shaft and sealing rod. The stirring body rotates while the impeller remains stationary, thus keeping both the cement slurry inside the stirring body and the simulated formation water outside the stirring body in a flowing state. The simulated formation water outside the stirring body passes through the simulated formation fracture mesh through the through hole 1. Some of the cement slurry enters the simulated formation water and flows into the stirring body. Observe and record the pH value and conductivity value at speed 1 to complete the test at speed 1. By adjusting the speed of the servo motor, observe and record the pH value and conductivity value at different speeds to complete the test at different speeds.

[0023] 5) Evaluate the water erosion resistance of the cement slurry based on the pH value and conductivity values ​​recorded in steps 3) to 4).

[0024] 6) Fill cement slurry with different formulations into cement silos and repeat steps 1) to 5) to evaluate the water erosion resistance of cement slurry with different formulations.

[0025] The beneficial effects of this invention are:

[0026] 1. The present invention provides an evaluation device and method for evaluating the resistance of cement slurry to dynamic water intrusion, comprising a conductivity meter, a pH meter, a controller, a vessel, a magnetic drive assembly, a metering pump, a servo motor, a cement tank, and a water tank. The cement tank is connected inside the vessel, and the power output end of the servo motor is connected to the cement tank through the magnetic drive assembly. The vessel is connected to the outer casing of the cement tank. One path of the water tank is connected to the vessel, and the other path of the water tank is connected to the vessel through the metering pump. The pH probe of the pH meter and the conductivity probe of the conductivity meter are both connected to the vessel. The water tank is filled with water.

[0027] 2. The cement slurry anti-dynamic water intrusion evaluation device and evaluation method provided by the present invention facilitates the realistic simulation of formation fractures by setting simulated formation fracture meshes on both the simulated mesh welding frame 2 and the simulated mesh welding frame 1.

[0028] 3. The cement slurry anti-dynamic water intrusion evaluation device and method provided by this invention, by setting the rotation speed of the servo motor, drives the outer magnetic component to rotate, which in turn drives the inner magnetic component to rotate. The inner magnetic component drives the stirring body to rotate through the cup platform. The impeller is connected to the vessel cover through the cup shaft and sealing rod. The stirring body rotates while the impeller remains stationary, so that the cement slurry inside the stirring body and the simulated formation water outside the stirring body are both in a flowing state. The simulated formation water outside the stirring body passes through the simulated formation fracture mesh through the through hole, and some cement slurry enters the simulated formation water and flows into the stirring body. The simulated formation water erodes the cement slurry through the formation fractures. By rotating the stirring body at different speeds, different water flow velocities and interference forces are formed. The simulated formation water interferes with the cement slurry at the cementing interface at different flow velocities. The cement slurry is disturbed and destroyed by the simulated formation water, and some cement slurry components enter the simulated formation water. The pH probe of the pH tester and the conductivity probe of the conductivity tester are both connected to the simulated formation water in the reactor. The pH value and conductivity value of the simulated formation water are tested and recorded. This is used to measure the change in the conductivity of the formation water after some cement slurry components enter the simulated formation water, so as to achieve qualitative and quantitative evaluation of the cement slurry's resistance to dynamic water intrusion.

[0029] 4. The cement slurry anti-dynamic water intrusion evaluation device and evaluation method provided by the present invention uses a metering pump to make the simulated formation water circulate between the vessel and the cement tank, which improves the simulation performance and the accuracy of the measurement.

[0030] 5. The present invention provides a device and method for evaluating the resistance of cement slurry to dynamic water intrusion. The cement tank is fitted with a vessel. The mixing body has multiple through holes circumferentially spaced. Simulated mesh welding frame 2 and simulated mesh welding frame 1 are connected sequentially from top to bottom in the mixing body between the pressure cap and the lower cap. Simulated formation fracture mesh is provided on both simulated formation fracture mesh. This structure allows simulated formation water to be filled between the vessel (i.e., the vessel and the cement tank) and cement slurry to be filled in the mixing body. The simulated formation water in the vessel and the cement slurry in the mixing body can be pressurized separately. The simulated formation water and cement slurry are only connected through the simulated formation fracture mesh (simulated formation fractures). This results in different pressure differences (measured by two pressure sensors) for cement slurries with different water-cement ratios, which facilitates the evaluation of the impact of the pressure difference between different cement slurries and formation water on various cement slurry formulations. Attached Figure Description

[0031] The present invention will now be described in further detail with reference to the accompanying drawings.

[0032] Figure 1 This is the main structural view of the cement slurry anti-dynamic water intrusion evaluation device for cementing.

[0033] Figure 2 This is a right-hand view of the structure of the cement slurry anti-dynamic water intrusion evaluation device for cementing.

[0034] Figure 3 This is a front view of the internal structure of the cement slurry anti-dynamic water intrusion evaluation device for cementing.

[0035] Figure 4 yes Figure 3 Right view of CC's structure;

[0036] Figure 5 This is the main structural view of the assembled cement silos;

[0037] Figure 6 yes Figure 5 AA's structural diagram;

[0038] Figure 7 This is the main structural view of the disassembled cement silo;

[0039] Figure 8 This is a top view of the simulated mesh welding frame;

[0040] Figure 9 yes Figure 8 AA structural diagram;

[0041] Figure 10 This is a front view of the structure after the vessel, cement tank, and magnetic drive assembly are connected.

[0042] Figure 11 This is a schematic diagram of a water-immersed hydraulic system.

[0043] Figure 12 Average torque of the blades.

[0044] Figure labeling: 1. Water tank; 2. Conductivity meter; 3. pH meter; 4. Controller; 5. Reactor body; 6. Magnetic drive assembly; 7. Metering pump; 8. Servo motor; 9. Cement silo; 10. Pressure regulating valve; 11. Control valve; 12. Safety valve; 13. Pulsation damper; 14. Solenoid valve; 15. Vibration platform; 16. Vibration motor; 17. Air-driven water pump; 5-1. Reactor body; 5-2. Sealing rod; 5-3. Reactor cover; 5-4. Sealing joint; 5 -5. Through hole two; 6-1. Inner magnetic assembly; 6-2. Outer magnetic assembly; 9-1. Stirring body; 9-2. Upper cover; 9-3. Lower cover; 9-4. Paddle; 9-5. Cup shaft; 9-6. Paddle fixing pin; 9-7. Simulated mesh welding frame one; 9-8. Pressure cap; 9-9. Pad three; 9-10. Screw plug; 9-11. Pad one; 9-12. Simulated mesh welding frame two; 9-13. Pad two; 9-14. Cup platform; 9-15. Through hole one; 9-16. Cover one. Detailed Implementation

[0045] Example 1:

[0046] like Figures 1-4 and Figure 11 As shown, a device for evaluating the resistance of cement slurry to dynamic water intrusion in well cementing includes a conductivity meter 2, a pH meter 3, a controller 4, a vessel 5, a magnetic drive assembly 6, a metering pump 7, a servo motor 8, a cement tank 9, and a water tank 1. The vessel 5 is connected to the cement tank 9. The power output end of the servo motor 8 is connected to the cement tank 9 through the magnetic drive assembly 6. The vessel 5 is connected to the outer casing of the cement tank 9. One path of the water tank 1 is connected to the vessel 5, and the other path of the water tank 1 is connected to the vessel 5 through the metering pump 7. The pH probe of the pH meter 3 and the conductivity probe of the conductivity meter 2 are both connected to the vessel 5. The water tank 1 is filled with water. The controller 4 is electrically connected to the conductivity meter 2, the pH meter 3, the magnetic drive assembly 6, the metering pump 7, the servo motor 8, and the water tank 1.

[0047] In use, the prepared cement slurry is filled into the cement tank 9, and the cement tank 9 containing the cement slurry is placed into the vessel cylinder 5. The simulated formation water in the water tank 1 is injected into the space between the vessel cylinder 5 and the cement tank 9. The pH probe of the pH tester 3 and the conductivity probe of the conductivity tester 2 are connected to the simulated formation water in the vessel cylinder 5, and the pH value and conductivity value of the simulated formation water are tested and recorded.

[0048] Start metering pump 7 to circulate the simulated formation water in vessel 5 and water tank 1 through pH and conductivity probes. After the pH and conductivity readings stabilize, check and record the pH and conductivity values. Start servo motor 8 at speed 1. Servo motor 8 drives magnetic drive assembly 6 to rotate, which in turn drives cement tank 9 to rotate. Record the pH and conductivity values ​​at speed 1 to complete the test at speed 1. Adjust the speed of servo motor 8 and check and record the pH and conductivity values ​​at different speeds to complete the test at different speeds. Evaluate the water erosion resistance of the cement slurry formula based on the recorded pH and conductivity values. Fill cement slurry with different formulas into cement tank 9 and repeat the above steps to evaluate the water erosion resistance of different cement slurry formulas, thus achieving a qualitative and quantitative evaluation of the dynamic water erosion resistance of the cement slurry.

[0049] The device has a simple structure. The metering pump 7 keeps the simulated formation water circulating between the vessel 5 and the cement tank 9, resulting in better simulation performance and improved measurement accuracy.

[0050] The water in water tank 1 is preferably simulated formation water, which can be configured according to actual conditions.

[0051] Preferably, the controller 4 is a PLC controller; the PLC controller collects and analyzes various data, has good real-time performance, high reliability, simple installation, and convenient maintenance.

[0052] Example 2:

[0053] Based on Example 1, such as Figure 10 As shown, the magnetic drive assembly 6 includes an inner magnetic assembly 6-1 and an outer magnetic assembly 6-2. The power output end of the servo motor 8 is connected to the outer magnetic assembly 6-2, and the inner magnetic assembly 6-1 is nested inside the outer magnetic assembly 6-2.

[0054] When the servo motor 8 rotates, it drives the outer magnetic component 6-2 to rotate, which in turn drives the inner magnetic component 6-1 to rotate, and the inner magnetic component 6-1 drives the stirring body 9-1 to rotate. Therefore, the inner magnetic component 6-1 and the outer magnetic component 6-2 are used for transmission. Since both the inner magnetic component 6-1 and the outer magnetic component 6-2 are magnetic components, they are small in size and have strong attraction. In actual use, as long as the outer magnetic component 6-2 can drive the inner magnetic component 6-1 to rotate when the servo motor 8 drives the outer magnetic component 6-2 to rotate, and the inner magnetic component 6-1 can drive the stirring body 9-1 to rotate, it is sufficient. The specific structure of the inner magnetic component 6-1 and the outer magnetic component 6-2 will not be described in detail here.

[0055] Example 3:

[0056] Based on Example 2, such as Figures 5-9As shown, the cement silo 9 includes a mixing body 9-1, an upper cover 9-2, a lower cover 9-3, a paddle 9-4, a cup shaft 9-5, a simulated mesh welding frame 9-7, a pressure cap 9-8, a screw plug 9-10, a simulated mesh welding frame 9-12, and a cover 9-16. The upper cover 9-2, cover 9-16, pressure cap 9-8, paddle 9-4, and lower cover 9-3 are sequentially fitted onto the outer side of the cup shaft 9-5 from top to bottom. The upper cover 9-2 and the lower cover 9-3 are connected... The mixing body 9-1 is connected to the cover 9-16, the pressure cover 9-8 and the blade 9-4 are all located inside the mixing body 9-1. Between the pressure cover 9-8 and the lower cover 9-3, the simulated mesh welding frame 9-12 and the simulated mesh welding frame 9-7 are connected from top to bottom inside the mixing body 9-1. The simulated stratum fracture mesh is connected to both the simulated mesh welding frame 9-12 and the simulated mesh welding frame 9-7. The lower end of the lower cover 9-3 is fitted with a screw plug 9-10.

[0057] In use, by setting the rotation speed of the servo motor 8, the servo motor 8 drives the outer magnetic component 6-2 to rotate, which in turn drives the inner magnetic component 6-1 to rotate. The inner magnetic component 6-1 drives the stirring body 9-1 to rotate via the cup platform 9-14. The impeller 9-4 is connected to the vessel cover 5-3 via the cup shaft 9-5 and the sealing rod 5-2. The stirring body 9-1 rotates while the impeller 9-4 remains stationary, thus keeping both the cement slurry inside the stirring body 9-1 and the simulated formation water outside the stirring body 9-1 in a flowing state. The simulated formation water outside the stirring body 9-1 enters the stirring body 9-1 and passes through the simulated formation fracture network. Some of the cement slurry enters the simulated formation water and flows out of the stirring body 9-1, eroding the cement slurry through the formation fractures. By adjusting the rotation speed of the stirring body 9-1, different water flow velocities and disturbance forces are formed. The simulated formation water interferes with the cement slurry at the cementing interface at different flow velocities. The cement slurry is disturbed and destroyed by the simulated formation water, and some cement slurry components enter the simulated formation water. The mixing body 9-1 rotates at a certain speed, and the impeller 9-4 generates a certain torque. As the cement slurry changes, the average torque continuously increases (see...). Figure 12 The instrument collects average torque data, which reflects the state of the cement slurry and prevents the slurry from solidifying and damaging the slurry cup and its internal components. The pH probe of the pH tester 3 and the conductivity probe of the conductivity tester 2 are both connected to the simulated formation water inside the vessel 5. They test and record the pH and conductivity values ​​of the simulated formation water, measuring the change in the conductivity of the formation water after some cement slurry components enter the simulated formation water, thus achieving a qualitative and quantitative evaluation of the cement slurry's resistance to dynamic water intrusion.

[0058] Preferably, the cement hopper 9 further includes a cup platform 9-14, the outer side of the screw plug 9-10 is sleeved on the cup platform 9-14 and the upper part of the cup platform 9-14 is connected to the lower part of the lower cover 9-3, and the middle part of the cup platform 9-14 is connected to the upper end of the inner magnetic assembly 6-1.

[0059] The cup platform 9-14 facilitates a secure connection between the inner magnetic component 6-1 and the cement jar 9, resulting in better device stability when the mixing body 9-1 of the cement jar 9 rotates.

[0060] Preferably, the cement silo 9 further includes gasket 1 9-11, gasket 2 9-13, and gasket 3 9-9; gasket 1 9-11 connects the screw plug 9-10 and the lower cover 9-3; gasket 2 9-13 connects the simulated mesh welding frame 2 9-12 and the mixing body 9-1; and gasket 3 9-9 connects the simulated mesh welding frame 1 9-7 and the mixing body 9-1. This improves the sealing performance of the cement silo 9.

[0061] Preferably, the blade 9-4 and the cup shaft 9-5 are connected by a blade fixing pin 9-6; the connection method is simple.

[0062] Preferably, the stirring body 9-1 has multiple through holes 9-15 spaced evenly in the circumferential direction.

[0063] Through hole 9-15 allows simulated formation water outside the mixing body 9-1 to pass through the simulated formation fracture mesh. Some cement slurry enters the simulated formation water and flows into the outside of the mixing body 9-1 through through hole 9-15. Multiple through holes 9-15 are opened at equal intervals in the circumferential direction, resulting in a stable structure and better simulation.

[0064] Example 4:

[0065] Based on Example 3, the vessel cylinder 5 includes a vessel body 5-1, a sealing rod 5-2, a vessel cover 5-3, and a sealing joint 5-4. The upper part of the cup shaft 9-5 is connected to the vessel cover 5-3 through the sealing rod 5-2. The vessel cover 5-3 is connected to the upper end of the vessel body 5-1. The upper end of the sealing rod 5-2 is connected to the sealing joint 5-4.

[0066] The vessel cylinder 5 in this structure is a sealing device, and the cement tank 9 is outer sleeved to the vessel cylinder 5. The stirring body 9-1 has multiple through holes 9-15 spaced evenly spaced circumferentially. Between the pressure cap 9-8 and the lower cap 9-3, the stirring body 9-1 is connected from top to bottom to a simulated mesh welding frame 9-12 and a simulated mesh welding frame 9-7. Both the simulated mesh welding frame 9-12 and the simulated mesh welding frame 9-7 are equipped with simulated geological fracture mesh. This structure allows for the connection between the vessel cylinder 5 (i.e., the vessel cylinder 5 and the cement tank 9) and the simulated geological fracture mesh. The vessel contains simulated formation water, and the mixing body 9-1 contains cement slurry. The simulated formation water in the vessel cylinder 5 and the cement slurry in the mixing body 9-1 can be pressurized separately (the pressurization can be carried out by an air-driven water pump 17). The simulated formation water and cement slurry are only connected through the simulated formation fracture network (simulated formation fractures), which makes the cement slurry with different water-cement ratios generate different pressure differences (measured by two pressure sensors). This makes it easy to evaluate the impact of the pressure difference between different cement slurries and formation water on various cement slurry formulations.

[0067] Preferably, the stirring body 9-1 and the vessel body 5-1 do not contact each other. This facilitates the inclusion of simulated formation water in the cavity between the stirring body 9-1 and the vessel body 5-1.

[0068] Preferably, the vessel body 5-1 includes a side plate and a bottom plate. The side plate is cylindrical, and its bottom surface is connected to the bottom plate. A through hole 5-5 is provided in the middle of the bottom plate, and the upper part of the inner magnetic component 6-1 is connected to the through hole 5-5. This structure is simple and facilitates simultaneous connection of the inner magnetic component 6-1 and the cement tank 9.

[0069] Preferably, the vessel body 5-1 is provided with a water inlet, a water outlet, a connection port for a conductivity meter 2, and a connection port for a pH meter 3; this facilitates water filling and drainage inside the vessel body 5-1, the connection port for the conductivity meter 2 facilitates connection to the conductivity probe of the conductivity meter 2, and the connection port for the pH meter 3 facilitates connection to the pH probe of the pH meter 3.

[0070] Example 5:

[0071] Based on Example 4, the cement slurry anti-dynamic water intrusion evaluation device for cementing also includes a vibration platform 15 and a vibration motor 16. The vibration platform 15 includes an upper platform, a spring and a lower platform. The upper platform is connected to the lower platform through the spring. The upper platform is connected to the bottom plate of the vessel and the vibration motor 16.

[0072] In use, the vibration platform 15 and the vibration motor 16 can serve as backup motors. When the servo motor 8 is under maintenance or malfunctions, the vibration motor 16 can be started. The vibration of the vibration motor 16 drives the vibration platform 15 to vibrate, and the vibration platform 15 drives the vessel cylinder 5 to vibrate. This keeps the cement slurry inside the mixing body 9-1 and the simulated formation water outside the mixing body 9-1 in a flowing state. The simulated formation water outside the mixing body 9-1 passes through the simulated formation fracture mesh through the through hole 9-15, and some of the cement slurry enters the simulated formation water and flows into the outside of the mixing body 9-1, thus improving the practicality and applicability of the device.

[0073] Example 6

[0074] Based on Example 5, pressure regulating valves 10 are installed between the conductivity meter 2 and the vessel 5, and between the metering pump 7 and the vessel 5. The pressure regulating valves 10 facilitate the adjustment of the pressure of the simulated formation water and the cement slurry in the mixing body 9-1.

[0075] Preferably, control valves 11 are provided between the water tank 1 and the pH meter 3, between the water tank 1 and the conductivity meter 2, and between the water tank 1 and the metering pump 7 for convenient control of opening and closing. The pH meter 3, the conductivity meter 2, and the pressure regulating valve 10 are all controlled to open and close via solenoid valves 14.

[0076] Preferably, the water tank 1 is connected in sequence to a safety valve 12, a solenoid valve 14, and a pulsation damper 13 via pipes. This arrangement can eliminate liquid pressure pulsations within the pipes of the water tank 1, thereby stabilizing fluid pressure and flow, eliminating pipe vibration, protecting downstream instruments and equipment, and increasing the volumetric efficiency of the metering pump.

[0077] Example 7:

[0078] Based on Example 6, the effect of different formation water flow velocities on various cement slurry formulations:

[0079] Inside the vessel, from the outside in, are simulated formation water, a stirring body 9-1, a simulated formation mesh, and cement slurry. A servo motor drives the stirring body 9-1 to rotate via magnetic transmission, while the impeller 9-4 remains stationary. This keeps both the cement slurry inside the stirring body 9-1 and the simulated formation water outside in a flowing state. The simulated formation water outside the stirring body 9-1 enters the stirring body 9-1 and passes through the simulated formation mesh. Some of the cement slurry enters the simulated formation water and flows out of the stirring body 9-1, eroding the cement slurry through the formation mesh. A conductivity probe is connected to the simulated formation water. Different stirring body rotation speeds create different water flow velocities and interference forces. The simulated formation water interferes with the cement slurry at the cementing interface at different flow velocities. The cement slurry is disrupted by the simulated formation water, and some cement slurry components enter the simulated formation water. The conductivity meter probe is placed in the simulated formation water to measure the change in the formation water conductivity after some cement slurry components enter the simulated formation water.

[0080] The evaluation method using the aforementioned cement slurry resistance to dynamic water intrusion evaluation device includes the following steps:

[0081] 1) Fill the cement slurry into the cement tank 9, place the cement tank 9 containing the cement slurry into the cup platform 9-14 inside the vessel cylinder 5, and inject the simulated formation water in the water tank 1 into the space between the vessel cylinder 5 and the cement tank 9.

[0082] Specifically, assemble cement tank 9, and pour cement slurry with the water-cement ratio prepared according to the standard "Test Method for Cement in Oil Wells" into the cup body of cement tank 9 according to the scale (too much cement slurry above the scale is easy to overflow, too little cement slurry below the scale is not conducive to improving the accuracy of measurement data); slowly put cement tank 9 containing cement slurry into cup platform 9-14 inside reactor body 5-1, then pour in simulated formation water to the same height as cement tank 9, and install reactor cover 5-3, sealing rod 5-2 and water inlet hose (note that they all have sealing rings), and pour simulated formation water into water tank (water level to 1 / 2). When using, pour the simulated formation water in water tank 1 into the space between reactor body 5 and cement tank 9;

[0083] 2) Connect the pH probe of pH meter 3 and the conductivity probe of conductivity meter 2 to the simulated formation water in the vessel 5, and test and record the pH and conductivity values ​​of the simulated formation water.

[0084] When in use, open the control valve (solenoid valve) connecting the pH value probe of pH tester 3 to the vessel 5, open the control valve (solenoid valve) connecting the conductivity test probe to the vessel body, and open the control valve (solenoid valve) of the regulating valve.

[0085] 3) Start metering pump 7 to allow the simulated formation water in vessel 5 and the simulated formation water in water tank 1 to circulate through the pH probe and conductivity probe. After the pH tester 3 and conductivity tester 2 stabilize, check and record the pH and conductivity values. When starting metering pump 7, open the control valve (solenoid valve) connecting metering pump 7 and vessel 5.

[0086] 4) Start the servo motor 8 at speed 1. The servo motor 8 drives the outer magnetic component 6-2 to rotate, which in turn drives the inner magnetic component 6-1 to rotate. The inner magnetic component 6-1 drives the stirring body 9-1 to rotate via the cup platform 9-14. The impeller 9-4 is connected to the vessel cover 5-3 via the cup shaft 9-5 and the sealing rod 5-2. The stirring body 9-1 rotates while the impeller 9-4 remains stationary, thus keeping both the cement slurry inside the stirring body 9-1 and the simulated formation water outside the stirring body 9-1 in a flowing state. The simulated formation water outside the stirring body 9-1 passes through the simulated formation fracture mesh via the through hole 9-15. Some of the cement slurry enters the simulated formation water and flows out of the stirring body 9-1. Observe and record the pH value and conductivity value at speed 1 to complete the test at speed 1. By adjusting the speed of the servo motor 8, observe and record the pH value and conductivity value at different speeds to complete the test at different speeds.

[0087] When in use, the servo motor can be started at 50 revolutions per minute. The servo motor speed can be set arbitrarily between 0.5 and 2000 revolutions per minute, and can be increased by 100 r / min each time for testing. In specific operation, the speed should be adjusted according to the actual situation to meet the usage requirements.

[0088] 5) Evaluate the water erosion resistance of the cement slurry based on the pH value and conductivity values ​​recorded in steps 3) to 4).

[0089] 6) Fill cement slurry with different formulations (prepare cement slurry with different water-cement ratios according to the specification "Test Methods for Cement in Oil Wells") into cement silo 9, and repeat steps 1) to 5) to evaluate the water erosion resistance of cement slurry with different formulations.

[0090] To achieve qualitative and quantitative evaluation of the dynamic water erosion resistance of cement slurry.

[0091] Example 8:

[0092] Based on Example 7, the influence of pressure differences between different cementing slurries and formation water on various cementing slurry formulations is investigated:

[0093] Inside the reactor vessel, from the outside in, are simulated formation water, a mixing body 9-1, a simulated formation mesh, and cement slurry. A metering pump pressurizes the cement slurry in the mixing body 9-1. The cement slurry in the mixing body 9-1 is connected to the simulated formation water inside the reactor vessel through the simulated formation mesh (simulated formation fissures). This creates different pressure differences between the cement slurry with different water-cement ratios and the simulated formation water. Ions and other components in the cement slurry permeate into the simulated formation water through diffusion and chemical potential difference, causing changes in the conductivity and pH value of the simulated formation water. The pH value and conductivity values ​​are observed and recorded to determine which cement slurry formulation has a stronger resistance to formation water erosion and interference.

[0094] The evaluation method using the aforementioned cement slurry resistance to dynamic water intrusion evaluation device includes the following steps:

[0095] An evaluation method based on the aforementioned cement slurry resistance to dynamic water intrusion evaluation device includes the following steps:

[0096] 1) Fill the cement slurry into the cement tank 9, place the cement tank 9 containing the cement slurry into the cup platform 9-14 inside the vessel cylinder 5, and inject the simulated formation water in the water tank 1 into the space between the vessel cylinder 5 and the cement tank 9.

[0097] Specifically, the cement slurry, prepared according to the standard "Test Method for Cement in Oil Wells" with the correct water-cement ratio, is injected into mixing tank 9-1 according to the marking requirements. After checking that all seals are intact, the top cover is tightened, and the cement tank 9 containing the cement slurry is slowly placed into the cup platform inside the reactor. Then, simulated formation water is injected to the same height as the cement tank 9, and the reactor lid, sealing rod, and inlet hose (note that they all have sealing rings) are installed. Simulated formation water is then injected into the water tank (to 1 / 2 full).

[0098] 2) Connect the pH probe of pH meter 3 and the conductivity probe of conductivity meter 2 to the simulated formation water in the vessel 5. Open pH meter 3, conductivity meter 2 and pressure regulating valve 10. Start servo motor 8 at speed 1. Servo motor 8 drives the outer magnetic component 6-2 to rotate. The outer magnetic component 6-2 drives the inner magnetic component 6-1 to rotate. The inner magnetic component 6-1 drives the stirring body 9-1 to rotate through the cup platform 9-14. The blade 9-4 is connected to the vessel cover 5-3 through the cup shaft 9-5 and the sealing rod 5-2. The stirring body 9-1 rotates while the blade 9-4 does not move, so that the cement slurry in the stirring body 9-1 and the simulated formation water outside the stirring body 9-1 are both in a flowing state. The simulated formation water outside the stirring body 9-1 passes through the simulated formation fracture mesh through the through hole 9-15. Some cement slurry enters the simulated formation water and flows into the outside of the stirring body 9-1. Check and record the pH value and conductivity value at speed 1.

[0099] 3) Turn on the metering pump 7 to pressurize the cement slurry in the cement tank 9 and check the pressure difference between the cement slurry in the cement tank 9 and the simulated formation water in the vessel 5. Record the values. The simulated formation water circulates through the pH value test probe and the conductivity test probe. After the values ​​stabilize, check and record the pH value and conductivity value.

[0100] 4) Evaluate the water erosion resistance of the cement slurry under different pressure conditions based on the pH value and conductivity values ​​recorded in steps 1) to 3).

[0101] 5) Fill cement slurry with different formulations into cement silo 9, and repeat steps 1) to 4) to evaluate the water erosion resistance of cement slurry with different formulations under different pressure conditions.

[0102] This study solved the problem of evaluating the anti-intrusion performance of cement slurry under dynamic pressure conditions.

[0103] In the description of this invention, it should be understood that if terms such as "upper" or "lower" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, it does not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are for illustrative purposes only and should not be construed as limiting the invention.

[0104] The above examples are merely illustrative of the present invention and do not constitute a limitation on the scope of protection of the present invention. All designs that are the same as or similar to the present invention are within the scope of protection of the present invention.

Claims

1. A device for evaluating the resistance of a cement slurry to dynamic water invasion for cementing, characterized in that it comprises: The system includes a conductivity meter (2), a pH meter (3), a controller (4), a vessel (5), a magnetic drive assembly (6), a metering pump (7), a servo motor (8), a cement tank (9), and a water tank (1). The cement tank (9) is installed inside the vessel (5). The power output of the servo motor (8) is connected to the cement tank (9) via the magnetic drive assembly (6). One path of the water tank (1) is connected to the vessel (5), and the other path of the water tank (1) is connected to the vessel (5) via the metering pump (7). The pH probe of the pH meter (3) and the conductivity probe of the conductivity meter (2) are both connected to the vessel (5). The water tank (1) is filled with water. The controller (4) is electrically connected to the conductivity meter (2), the pH meter (3), the pH meter (4), the pH meter (5), the pH meter (6), the pH meter (7), the pH meter (8), the pH meter (9 ... 3) Magnetic drive assembly (6), metering pump (7), and servo motor (8); the magnetic drive assembly (6) includes an inner magnetic assembly (6-1) and an outer magnetic assembly (6-2), the power output end of the servo motor (8) is connected to the outer magnetic assembly (6-2), and the inner magnetic assembly (6-1) is sleeved inside the outer magnetic assembly (6-2); the cement tank (9) includes a stirring body (9-1), an upper cover (9-2), a lower cover (9-3), a paddle (9-4), a cup shaft (9-5), a simulated mesh welding frame one (9-7), a pressure cap (9-8), a screw plug (9-10), a simulated mesh welding frame two (9-12), and a cover one (9-16), with the upper cover (9-2) sleeved sequentially from top to bottom on the outside of the cup shaft (9-5). The structure consists of a cover (9-16), a pressure cover (9-8), a paddle (9-4), and a lower cover (9-3). An agitator (9-1) connects the upper cover (9-2) and the lower cover (9-3). The cover (9-1), pressure cover (9-8), and paddle (9-4) are all located within the agitator (9-1). Within the agitator (9-1) between the pressure cover (9-8) and the lower cover (9-3), two simulated mesh welding frames (9-12) and one simulated mesh welding frame (9-7) are connected sequentially from top to bottom. Simulated stratum fracture mesh is installed on both the simulated mesh welding frames (9-12) and one simulated mesh welding frame (9-7). A screw plug (9-10) is fitted over the lower end of the lower cover (9-3). The cement silo (9) also includes... The vessel includes a cup platform (9-14), a screw plug (9-10) sleeved on the outside of the cup platform (9-14), and the upper part of the cup platform (9-14) is connected to the lower part of the lower cover (9-3). The lower part of the middle part of the cup platform (9-14) is connected to the upper part of the inner magnetic component (6-1). The vessel cylinder (5) includes a vessel body (5-1), a sealing rod (5-2), a vessel cover (5-3), and a sealing joint (5-4). The upper part of the cup shaft (9-5) is sleeved on the vessel cover (5-3) through the sealing rod (5-2). The vessel cover (5-3) is sleeved on the upper part of the vessel body (5-1). The upper part of the sealing rod (5-2) is connected to the sealing joint (5-4). The stirring body (9-1) has multiple through holes (9-15) evenly spaced around the circumference.

2. The apparatus of claim 1, wherein: The stirring body (9-1) does not come into contact with the vessel body (5-1).

3. The apparatus of claim 2, wherein: The vessel body (5-1) includes a side plate and a bottom plate. The side plate is cylindrical and the bottom surface of the side plate is connected to the bottom plate. A through hole (5-5) is provided in the middle of the bottom plate, and the upper part of the inner magnetic component (6-1) is connected to the through hole (5-5).

4. The apparatus of claim 1, wherein: Pressure regulating valves (10) are provided between the conductivity tester (2) and the vessel (5), and between the metering pump (7) and the vessel (5).

5. An evaluation method for the device for evaluating the resistance of a cement slurry for well cementing to dynamic water invasion according to any one of claims 1 to 4, characterized in that, Includes the following steps: 1) Fill the cement slurry prepared according to the formula into the cement tank (9), put the cement tank (9) containing the cement slurry into the cup platform (9-14) inside the kettle cylinder (5), and inject the simulated formation water in the water tank (1) into the space between the kettle cylinder (5) and the cement tank (9). 2) Connect the pH probe of the pH tester (3) and the conductivity probe of the conductivity tester (2) to the simulated formation water in the vessel (5), and test and record the pH value and conductivity value of the simulated formation water. 3) Start the metering pump (7) to allow the simulated formation water in the vessel (5) and the simulated formation water in the water tank (1) to circulate through the pH probe and conductivity probe. After the pH tester (3) and conductivity tester (2) values ​​stabilize, check and record the pH value and conductivity value. 4) Start the servo motor (8) at a certain speed. The servo motor (8) drives the outer magnetic assembly (6-2) to rotate. The outer magnetic assembly (6-2) drives the inner magnetic assembly (6-1) to rotate. The inner magnetic assembly (6-1) drives the stirring body (9-1) to rotate through the cup platform (9-14). The impeller (9-4) is connected to the lid (5-3) through the cup shaft (9-5) and the sealing rod (5-2). The stirring body (9-1) rotates while the impeller (9-4) remains stationary, thus making the stirring body (9-1) rotate. The simulated formation water outside the cement slurry and the mixing body (9-1) is in a flowing state. The simulated formation water outside the mixing body (9-1) passes through the simulated formation fracture mesh through the through hole one (9-15). Some cement slurry enters the simulated formation water and flows into the outside of the mixing body (9-1). The pH value and conductivity value at the first rotation speed are viewed and recorded to complete the test at the first rotation speed. By adjusting the rotation speed of the servo motor (8), the pH value and conductivity value at different rotation speeds are viewed and recorded to complete the test at different rotation speeds. 5) Evaluate the water erosion resistance of the cement slurry based on the pH and conductivity values ​​recorded in steps 3) to 4). 6) Fill cement slurry with different formulations into cement silo (9), and repeat steps 1) to 5) to evaluate the water erosion resistance of cement slurry with different formulations.

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