Dual-system rapid ultrahigh pressure tracking mechanism for evaluating sealing integrity of cement sheath

Abstract

The invention discloses a dual-system rapid ultrahigh-pressure tracking mechanism for evaluating the sealing integrity of a cement sheath. The dual-system rapid ultrahigh-pressure tracking mechanism comprises a first high-pressure stress cabin and a second high-pressure stress cabin, the two ends of the adjusting device are connected with the first high-pressure stress cabin and the second high-pressure stress cabin through pulling assemblies correspondingly, displacement detection pieces are arranged on the pulling assemblies, and the ends, away from the adjusting device, of the first high-pressure stress cabin and the second high-pressure stress cabin are each provided with a valve assembly, a pressure detection assembly and a water supply piece through pipelines; the controller is electrically connected with the adjusting device, the valve assembly, the pressure detection assembly, the displacement detection piece and the water supply piece, the controller is used for presetting a detection numerical value of the displacement detection piece and controlling the moving distance of the adjusting device towards the first high-pressure stress cabin or the second high-pressure stress cabin according to the detection numerical value, and reciprocating control is conducted in this way; rapid liquid adding under the ultrahigh pressure condition can be achieved, the liquid adding process is continuous, and the functions of pressure gradient loading and automatic pressure tracking during alternating stress simulation are achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of oil and gas drilling, and particularly relates to a dual-system rapid ultra-high pressure tracking mechanism for evaluating the sealing integrity of a cement sheath. Background Art

[0002] In oil and gas well cementing, the sealing integrity of the cement sheath is crucial for wellbore safety. In recent years, as oilfield exploration and development have advanced deeper, formation pressures have continued to rise and geological conditions have become increasingly complex. At the same time, during the well construction, well testing, and later transformation processes of oil and gas wells, the pressure inside the wellbore changes drastically. Since cement stone itself is a brittle material, under stress, it is extremely easy to cause tensile, yield, fatigue, etc. failures of the cement sheath, which in turn leads to the failure of the cement sheath integrity and problems such as annulus pressure buildup, seriously threatening the safe production of oil and gas wells and even potentially resulting in the abandonment of the entire well, causing huge economic losses.

[0003] At present, for the problem of evaluating the sealing integrity of the cement sheath under ultra-high pressure conditions, the main research method is to carry out the design and development of experimental analysis equipment for the sealing integrity of the cement sheath applicable to ultra-high pressure conditions. In the existing technology, the patent publication number CN103498662A discloses a mechanical experimental device for the structural integrity of the cement sheath, which is composed of a cement sheath curing mold and a triaxial stress curing kettle. The cement sheath curing mold is arranged in the inner cavity of the triaxial stress curing kettle; the cement sheath curing mold includes an adjustable eccentric upper flange cover, a simulated wellbore, an outer casing for the simulated wellbore, a casing, and an adjustable eccentric lower flange plate. The outer casing for the simulated wellbore is sleeved outside the simulated wellbore. Both ends of the outer casing for the simulated wellbore are provided with flanges. The outer casing for the simulated wellbore is fixed between the adjustable eccentric upper flange cover and the adjustable eccentric lower flange plate. The sleeve is inserted into the simulated wellbore and fixedly connected to the adjustable eccentric lower flange plate. Cement slurry is filled between the simulated wellbore and the casing; strain gauges are arranged on both the inner and outer walls of the simulated wellbore, and the strain gauges are connected to data transmission lines; the triaxial stress curing kettle includes a cylindrical container, a confining pressure oil cylinder, an oil cylinder piston, an axial pressure piston, a confining pressure piston, a ring-shaped heating element, and an electrode. A confining pressure piston is arranged in the cylindrical container. The confining pressure oil cylinder is seated on the upper end face of the cylindrical container. A cushion block is pressed on the upper end face of the confining pressure piston. The lower end of the oil cylinder piston is buckled on the cushion block. The upper part of the oil cylinder piston passes through the confining pressure oil cylinder. The axial pressure piston passes through the oil cylinder piston and then inserts into the confining pressure piston. A silicone oil cavity is arranged between the confining pressure oil cylinder and the oil cylinder piston. An axial pressure sensor is connected to the axial pressure piston, and a press upper plate is arranged at the upper end of the axial pressure sensor; a ring-shaped heating element is arranged inside the cylindrical container. A Cu ring is arranged between the confining pressure piston and the ring-shaped heating element. The lower end face of the ring-shaped heating element is pressed on the electrode. The Cu ring, the ring-shaped heating element, and the electrode enclose an inner cavity. The ring-shaped heating element is connected to a thermocouple; the lower end of the electrode is inserted into an electrode seat, and the electrode seat is filled with liquid metal. The electrode seat is seated on the press lower plate; the axial pressure piston and the axial pressure sensor are connected by another cushion block. The lower end face of this cushion block has a concave arc surface, and the upper end face of the axial pressure piston is a convex arc surface. The axial pressure piston abuts against the lower part of the cushion block, and the axial pressure sensor is installed on the upper end face of the cushion block; a Pb ring is also arranged between the Cu ring and the confining pressure piston; a heat insulation layer is arranged between the ring-shaped heating element and the cylindrical container, and a cooling device is surrounded outside the cylindrical container; a sealing ring is arranged at the joint of the confining pressure oil cylinder and the oil cylinder piston. This device adopts a casing-cement sheath-artificial core wellbore structure, simulates the damage to the cement sheath during the oil and gas production and development process by applying different loads, and simultaneously tests the cementing quality at the first and second interfaces of the cement sheath by means of ventilation.

[0004] Patent Publication No. CN111287731A discloses a device and method for evaluating the integrity of a cement sheath in a well cementing operation, which includes an upper end cap, a lower end cap and a simulated wellbore. The middle part of the upper end cap and the lower end cap is the simulated wellbore. Flanges are welded at both ends of the outside of the simulated wellbore. From the inside to the outside in the middle of the simulated wellbore are an inner casing, a rubber sleeve assembly and an outer casing. Flanges are welded at both ends of the outer casing. A filter screen assembly is provided between the rubber sleeve assembly and the lower end cap. The rubber sleeve assembly includes a rubber sleeve and a steel skeleton. The rubber sleeve is vulcanized on the inner layer of the steel skeleton. The simulated cement sheath is between the rubber sleeve assembly and the inner casing. The outside of the outer casing is an insulating layer. The filter screen assembly is a composite annular structure, which from top to bottom is a filter screen mounted on a grooved filter screen skeleton. Through holes for connecting a thermocouple, a connecting pipe for injecting liquid pressure into the simulated inner casing, a connecting pipe for injecting liquid pressure into the simulated cement sheath and a connecting pipe for the drain port are respectively opened on the upper end cap. Through holes for connecting a heating pipe, a channeling inspection port, a discharge port for the liquid pressure of the simulated cement sheath and a connecting pipe for the discharge port of the liquid pressure of the simulated inner casing are opened on the lower end cap. A thermocouple is inserted into the central through hole of the upper end cap. A through hole for connecting the connecting pipe for injecting liquid pressure into the simulated inner casing is plugged at the position corresponding to the cavity of the inner casing on the upper end cap. A through hole for connecting the connecting pipe for injecting liquid pressure into the simulated cement sheath and the connecting pipe for the drain port of the liquid pressure of the simulated cement sheath is plugged at the position corresponding to the annulus between the rubber sleeve and the inner casing on the upper end cap. Through holes for connecting a simulated formation liquid pressure injection port, a simulated formation liquid pressure drain port and a connecting pipe for the discharge port of the simulated formation liquid pressure are opened at the upper port of the annulus between the outer casing and the rubber sleeve assembly corresponding to the side wall of the simulated wellbore. The lower port of the annulus between the outer casing and the rubber sleeve assembly is the channeling inspection port. The combination of an O-ring seal and a sealing retaining ring is used for sealing between the inner casing and the upper end cap and the lower end cap. Each layer space of the inner casing and the rubber sleeve assembly is sealed by the respective layer sealing rings between it and the upper end cap and the lower end cap. The heating pipe is located at the center of the lower end cap, and its sealing method with the lower end cap is the end face seal of a copper gasket. An electronic balance is placed below the channeling inspection port.

[0005] This device adopts a casing-cement sheath-rubber sleeve structure, transfers the formation pressure to the cement sheath through the rubber sleeve, adjusts the pressure of the inner casing according to the actual downhole working conditions, and inspects the channeling situation caused by the damage of the cement sheath during the whole process.

[0006] Patent Publication No. CN110954683A discloses an evaluation device for the integrity and anti-channeling ability of cement stone. This device adopts a double-casing structure. By injecting cement slurry between the inner and outer casings and allowing it to solidify for a certain period of time under certain curing temperature and pressure, the evaluation device is fixed into a high-temperature and high-pressure fluid loss instrument or a similar fluid loss test device, and an external nitrogen source is connected to conduct channeling tests, so as to evaluate the anti-channeling ability of the cement sheath. However, limited by factors such as the pump body structure and functional design, existing experimental analysis equipment for the sealing integrity of cement sheaths generally has problems such as low injection / discharge flow rates under high-pressure conditions or high injection / discharge flow rates but low pressure indicators, and is unable to achieve pressure gradient adjustment and maintain pressure tracking, making it difficult to meet the requirements for testing the sealing integrity of cement sheaths under high-pressure and rapid alternating load conditions. Patent Publication No. CN116591925A discloses a plunger-type reciprocating high-pressure pump with adjustable flow rate. This high-pressure pump adjusts the flow rate of the high-pressure pump by connecting a pressure regulating valve at the liquid outlet of the high-pressure pump and manually opening and adjusting the pressure regulating valve. This patent only solves the problem of adjustable high-pressure flow rate, which belongs to sacrificing flow rate to meet high-pressure injection performance and is unable to meet the requirements for rapid injection under ultra-high-pressure conditions. Patent Publication No. CN116447100A discloses a non-eccentric wear horizontal ultra-high-pressure pump. This pump adopts a structure similar to a crank-slider mechanism, and drives a disc (crank) to rotate through a belt drive to convert the circumferential power into reciprocating linear power, thereby driving the plunger to inject fluid into the pipeline. At the same time, all connecting components of this pump adopt universal couplings. This patent belongs to sacrificing ultra-high pressure to meet the requirements for rapid liquid inlet under medium-high pressure conditions, but is unable to meet the requirements for rapid liquid addition under ultra-high-pressure conditions and the pressure gradient adjustment and maintenance of pressure tracking during the alternating stress of the cement sheath. Summary of the Invention

[0007] The purpose of the present invention is to solve the problems in the prior art, and provides a dual-system rapid ultra-high-pressure tracking mechanism for evaluating the sealing integrity of a cement sheath.

[0008] To achieve the above purpose, the present invention adopts the following technical solutions to implement:

[0009] A dual-system rapid ultra-high-pressure tracking mechanism for evaluating the sealing integrity of a cement sheath, comprising:

[0010] A first high-pressure stress chamber and a second high-pressure stress chamber;

[0011] Adjusting device, both ends of which are respectively connected to the first high-pressure stress chamber and the second high-pressure stress chamber through pulling components, and a displacement detector is provided on the pulling component. Valves, pressure detectors and water supply components are installed at one ends of the first high-pressure stress chamber and the second high-pressure stress chamber far away from the adjusting device through pipelines; Controller, electrically connected to the adjusting device, the valve component, the pressure detector, the displacement detector and the water supply component, and the controller is used to preset the detection value of the displacement detector and control the moving distance of the adjusting device to the first high-pressure stress chamber or the second high-pressure stress chamber according to the detection value.

[0012] Further, the adjusting device includes a driving component, a worm gear component and a connecting component. The worm gear component is installed outside the connecting component, the driving component is installed on the worm gear component, and both ends of the connecting component are movably connected to the first high-pressure stress chamber and the second high-pressure stress chamber respectively;

[0013] The pulling components are installed on both sides of the worm gear component, and the ends are respectively fixedly connected to the first high-pressure stress chamber and the second high-pressure stress chamber, and the displacement detector is installed on the pulling component;

[0014] The driving component is used to drive the worm gear component to drive the connecting component to perform linear reciprocating motion in the first high-pressure stress chamber or the second high-pressure stress chamber.

[0015] Further, the connecting component includes a reciprocating plunger and a ball screw. The reciprocating plunger includes a movable end and a connecting end, and the movable end and the connecting end are of an integral structure;

[0016] The movable ends of the reciprocating plunger respectively extend into the first high-pressure stress chamber and the second high-pressure stress chamber, and the connecting ends of the reciprocating plunger are respectively matched with the ball screw and the pulling component;

[0017] The worm gear component includes a worm gear box and a connecting shaft. The pulling component is installed on the worm gear box. The connecting shaft is of a hollow structure, installed in the worm gear box and sleeved outside the ball screw. Two corresponding through holes are opened at both ends of the worm gear box. One end of the through hole is connected to one end of the connecting shaft through a thrust ball bearing, and a lead screw nut is provided in the through hole at the other end. One end of the connecting shaft is fixedly connected to the lead screw nut through a bolt.

[0018] Further, a union nut is provided outside the through hole at one end of the worm gear box corresponding to the thrust ball bearing;

[0019] A worm gear and a first tapered roller bearing are also provided in the worm gear box, and both the worm gear and the first tapered roller bearing are sleeved outside the connecting shaft and are located on the side of the thrust ball bearing away from the union nut;

[0020] The other end of the connecting shaft is fixedly connected to the worm gear box through the union nut, and a worm gear adjusting washer is provided between the first tapered roller bearing and the thrust ball bearing.

[0021] Further, the connecting end of the reciprocating plunger is of a T-shaped structure, including a horizontal part and a vertical part. The vertical part of the connecting end is connected to the movable end of the reciprocating plunger, and the middle of the horizontal part of the connecting end is connected to the ball screw and positioned by a positioning pin.

[0022] Both ends of the horizontal part of the connecting end are connected with centering rings, and the two centering rings are respectively matched with the pulling components at the upper and lower ends of the worm gear box.

[0023] Further, the pulling component includes a pull rod, and there are two groups of pull rods, which are respectively arranged on the opposite sides of the worm gear box.

[0024] The number of each group of pull rods is two, and one is arranged at the upper and lower ends of the opposite sides of the worm gear box.

[0025] Further, the structures of the first high-pressure stress chamber and the second high-pressure stress chamber are the same.

[0026] Further, the outer side of the first high-pressure stress chamber is fixedly connected with a connecting front support seat and locked by a locking cap, and both ends of the connecting front support seat are matched with the pulling components.

[0027] Further, a connecting compression cap is also connected to the outer side of the first high-pressure stress chamber, and the connecting compression cap is located at one end of the first high-pressure stress chamber close to the pulling component.

[0028] Further, a sealing retaining ring, an energy storage sealing ring and a guide sleeve are arranged in the first high-pressure stress chamber, and the sealing retaining ring, the energy storage sealing ring and the guide sleeve are sequentially arranged at intervals at one end of the first high-pressure stress chamber close to the pulling component.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] 1. The dual-system rapid ultra-high pressure tracking mechanism adopts a driving component supporting a dual-system high-pressure stress chamber. The reciprocating plunger is driven by the driving component to achieve rapid reciprocating motion. When one end of the reciprocating plunger moves to the left, high-pressure fluid is injected into the first high-pressure stress chamber, and at the same time, the other end of the reciprocating plunger also moves to the left to suck liquid into the second high-pressure stress chamber. Conversely, when the driving component reverses, the worm and the worm gear are controlled to reverse, and at the same time, the lead screw nut is controlled to reverse, driving the ball screw and the reciprocating plunger to move to the right. At this time, the first high-pressure stress chamber is a low-pressure liquid suction chamber, and the second high-pressure stress chamber is a high-pressure injection chamber. A displacement sensor is designed on the pulling component, and the upper and lower limits of the displacement can be set. When one end of the reciprocating plunger moves to the left to the set upper limit of the displacement, the driving component is controlled to stop rotating forward and control the reverse rotation to drive the reciprocating plunger to move to the right. By controlling in this way back and forth, rapid liquid addition under ultra-high pressure conditions is realized, and this liquid addition process is a continuous operation, with pressure gradient loading during alternating stress simulation and the function of automatic pressure tracking.

[0031] 2. The reciprocating plunger is processed from 17-4PH precipitation hardening stainless steel, and the surface is treated with a special heat treatment process to obtain a higher hardness and have higher wear resistance, greatly improving the service life. At the same time, the surface of the reciprocating plunger has been precision ground, with a relatively high surface roughness, improving the sealing performance of the sealing parts.

[0032] 3. A worm gear box is installed in the adjusting device, which has a high-speed self-lubricating function. The worm gear box is designed as a sealed structure. When the worm gear runs at high speed, it drives the lubricating liquid in the worm gear box to flow to achieve the self-lubricating function, increasing the transmission efficiency.

[0033] 4. A water supply component is installed in the dual-system rapid ultra-high pressure tracking mechanism, which can realize the function of water replenishment. When the water supply component is short of water, the water pump pumps water from the outside into the interior of the water supply component, and the filter screen filters the water, and the water flows into the pipeline from the outlet pipe, realizing the function of water replenishment. Description of the Drawings

[0034] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required to be used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention, and therefore should not be regarded as a limitation of the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.

[0035] Figure 1 It is a schematic diagram of the overall dual-system rapid ultra-high pressure tracking mechanism for cement ring seal integrity evaluation provided by the present invention;

[0036] Figure 2 It is a schematic sectional view of the adjusting device of the dual-system rapid ultra-high pressure tracking mechanism for cement ring seal integrity evaluation provided by the present invention;

[0037] Figure 3 Schematic diagram of the installation of the driving component in the dual-system rapid ultra-high pressure tracking mechanism for evaluating the cement sheath sealing integrity provided by the present invention;

[0038] Wherein:

[0039] 1-1, First ultra-high pressure pneumatic valve; 2-2, Ultra-high pressure sensor; 3-3, High-pressure connection tee; 4-4, Second ultra-high pressure pneumatic valve; 5-5, Ultra-high pressure pipeline; 6-6, Third ultra-high pressure pneumatic valve; 7-7, Fourth ultra-high pressure pneumatic valve; 8-8, Cement sheath sealing integrity evaluation model; 9-9, Dual-system rapid ultra-high pressure tracking mechanism; 10-10, Displacement sensor; 11-11, Water tank; 12-12, PLC control system; 1, First high-pressure stress chamber; 2, Reciprocating plunger; 3, Locking cap; 4, Connecting front support seat; 5, Sealing ring; 6, Accumulator sealing ring; 7, Guide sleeve; 8, Connecting compression cap; 9, Centering ring; 10, Tie rod; 11, Positioning pin; 12, Ball screw; 13, Union nut; 14, Thrust ball bearing; 15, Connecting shaft; 16, Screw nut; 17, Worm gear adjusting washer; 18, Worm gear; 19, Worm; 20, First tapered roller bearing; 21, Worm gear box; 22, Bearing gland; 23, Second tapered roller bearing; 24, Reducer connecting sleeve; 25, Flexible coupling; 26, Reducer; 27, Motor. Specific embodiments

[0040] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Usually, the components of the embodiments of the present invention described and illustrated herein can be arranged and designed in various different configurations.

[0041] Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0042] It should be noted that: Similar reference numerals and letters denote similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0043] In the description of the embodiments of the present invention, it should be noted that if terms such as "upper", "lower", "horizontal", "inner", etc. are used to indicate the orientation or positional relationship, it is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the invention product is usually placed during use. This is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of the present invention. In addition, terms such as "first", "second", etc. are only used for distinguishing descriptions and cannot be construed as indicating or implying relative importance.

[0044] In addition, if the term "horizontal" appears, it does not mean that the component is required to be absolutely horizontal, but it can be slightly inclined. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and it does not mean that the structure must be completely horizontal, but it can be slightly inclined.

[0045] In the description of the embodiments of the present invention, it should also be noted that unless otherwise clearly specified and limited, if terms such as "set", "installed", "connected", "coupled" are used, they should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0046] The following further describes the present invention in detail with reference to the drawings:

[0047] Such as Figure 1As shown in the figure, an embodiment of the present invention provides a dual-system rapid ultra-high pressure tracking mechanism for evaluating the sealing integrity of a cement sheath. The dual-system rapid ultra-high pressure tracking mechanism 9-9 includes: a first high-pressure stress chamber 1 and a second high-pressure stress chamber, and the structures of the first high-pressure stress chamber and the second high-pressure stress chamber are the same; an adjusting device, both ends of which are respectively connected to the first high-pressure stress chamber 1 and the second high-pressure stress chamber through pulling components, and a displacement detector is arranged on the pulling components. Valves, pressure detection components and water supply components are installed at the ends of the first high-pressure stress chamber 1 and the second high-pressure stress chamber away from the adjusting device through pipelines; a controller, which is electrically connected to the adjusting device, the valve assembly, the pressure detection component, the displacement detector and the water supply component, and the controller is used to preset the detection value of the displacement detector and control the moving distance of the adjusting device to the first high-pressure stress chamber 1 or the second high-pressure stress chamber according to the detection value. Further, the pressure detection component includes a pipeline and an ultra-high pressure sensor 2-2. The pipeline is an ultra-high pressure pipeline 5-5, and both ends of the ultra-high pressure pipeline 5-5 are respectively connected to the first high-pressure stress chamber 1 and the second high-pressure stress chamber. The valve assembly includes a first ultra-high pressure pneumatic valve 1-1, a second ultra-high pressure pneumatic valve 4-4, a third ultra-high pressure pneumatic valve 6-6 and a fourth ultra-high pressure pneumatic valve 7-7. High-pressure connection tees 3-3 are connected to both ends of the first high-pressure stress chamber 1 and the second high-pressure stress chamber. One end of the high-pressure connection tee 3-3 at one end of the first high-pressure stress chamber 1 is connected to one end of the ultra-high pressure pipeline 5-5, and the other end is connected to an ultra-high pressure sensor 2-2. The first ultra-high pressure pneumatic valve 1-1 and the second ultra-high pressure pneumatic valve 4-4 are both installed at the end where the ultra-high pressure pipeline 5-5 is connected to the first high-pressure stress chamber 1; both ends of the high-pressure connection tee 3-3 at one end of the second high-pressure stress chamber are respectively connected to a third ultra-high pressure pneumatic valve 6-6 and a fourth ultra-high pressure pneumatic valve 7-7 through the ultra-high pressure pipeline 5-5. At the same time, the water supply component is connected to one end of the ultra-high pressure pipeline 5-5 connected to the second high-pressure stress chamber. Specifically, the water supply component is a water tank 11-11; the controller is a PLC control system 12-12, such as Figure 1As shown, when evaluating the cement sheath seal integrity in this embodiment, the cement sheath seal integrity evaluation model 8-8 is connected to the ultra-high pressure pipeline 5-5 to connect the cement sheath seal integrity evaluation model 8-8 with the entire mechanism. Then, the power button on the regulating device is activated, and at the same time, the tracking pressure is set on the PLC control system 12-12. The second ultra-high pressure pneumatic valve 4-4 and the fourth ultra-high pressure pneumatic valve 7-7 are opened, and the first ultra-high pressure pneumatic valve 1-1 and the third ultra-high pressure pneumatic valve 6-6 are closed. The regulating device is controlled to move to the right, and the liquid in the water tank 11-11 is sucked into the first high-pressure stress chamber 1. The detection end of the displacement detection component faces the regulating device. When the regulating device moves to the displacement limit position set by the displacement detection component, the PLC control system 12-12 controls the regulating device to stop moving, and closes the second ultra-high pressure pneumatic valve 4-4 and the fourth ultra-high pressure pneumatic valve 7-7. At the same time, it controls the regulating device to move in the reverse direction and opens the first ultra-high pressure pneumatic valve 1-1 and the third ultra-high pressure pneumatic valve 6-6. At this time, the regulating device moves to the left, and the liquid in the first high-pressure stress chamber 1 is injected into the cement sheath seal integrity evaluation model 8-8 through the high-pressure connection tee 3-3 and the ultra-high pressure pipeline 5-5; the pump working pressure can be read according to the ultra-high pressure sensor 2-2. While injecting fluid into the first high-pressure stress chamber 1, the second high-pressure stress chamber sucks liquid, and the above alternating work is completed to achieve uninterrupted and efficient injection; when the dual-system rapid ultra-high pressure tracking mechanism 9-9 needs to complete alternating stress loading, the first ultra-high pressure pneumatic valve 1-1 and the third ultra-high pressure pneumatic valve 6-6 are controlled to open, and the second ultra-high pressure pneumatic valve 4-4 and the fourth ultra-high pressure pneumatic valve 7-7 are closed. The PLC control system controls the regulating device to move to the right in the reverse direction. During pressure tracking, an on-line programmable data processing module is provided in the PLC controller 12-12. The pressure self-tuning is realized by collecting the pressure value and transmitting it to the on-line programmable data processing module in real time. When the working pressure reaches the set target value, the liquid inlet is automatically stopped and the connection valve is closed. When the working pressure is lower than the set target value, the dual-system rapid ultra-high pressure tracking mechanism 9-9 automatically feeds liquid until the working pressure reaches the set target pressure value. When the working pressure is higher than the set target value, the dual-system rapid ultra-high pressure tracking mechanism 9-9 automatically withdraws the pump to drain the liquid and reduce the pressure until the working pressure reaches the set target pressure value. Through the above feedback control mode, the functions of alternating stress boosting, pressure reduction control, and pressure automatic tracking are realized.

[0048] In this embodiment, the adjusting device includes a driving component, a worm gear component, and a connecting component. The worm gear component is installed outside the connecting component, the driving component is installed on the worm gear component, and both ends of the connecting component are movably connected to the first high-pressure stress chamber 1 and the second high-pressure stress chamber respectively; the pulling component is installed on both sides of the worm gear component, and its ends are fixedly connected to the first high-pressure stress chamber 1 and the second high-pressure stress chamber respectively, and the displacement detecting member is installed on the pulling component; the driving component is used to drive the worm gear component to drive the connecting component to perform a linear reciprocating motion in the first high-pressure stress chamber 1 or the second high-pressure stress chamber. Specifically, as Figure 3 shown, the driving component includes a reducer connecting sleeve 24, a flexible coupling 25, a reducer 26, and a motor 27. The motor 27 is a servo motor. The motor 27 is connected to the reducer 26. The end of the reducer 26 is connected with a flexible coupling 25. A reducer connecting sleeve 24 is fixedly connected to the flexible coupling 25. The reducer connecting sleeve 24 is connected to the second tapered roller bearing 23, and the second tapered roller bearing 23 corresponds to the bearing gland 22; the displacement detecting member is a displacement sensor 10-10. During the operation, the driving component is driven by the PLC controller, and the driving component drives the connecting component to perform a linear reciprocating motion in the first high-pressure stress chamber 1 or the second high-pressure stress chamber through the worm gear component; furthermore, as Figure 1 shown in and the figure, the connecting component includes a reciprocating plunger 2 and a ball screw 12. The reciprocating plunger 2 is processed from 17-4PH precipitation hardening stainless steel, and its surface is treated with a special heat treatment process to obtain a higher hardness and have a higher wear resistance, greatly improving the service life; at the same time, the surface of the reciprocating plunger 2 is finely ground to have a higher surface roughness, improving the sealing performance of the seal. The reciprocating plunger 2 includes a movable end and a connecting end, and the movable end and the connecting end are of an integral structure; the movable ends of the reciprocating plunger 2 extend into the first high-pressure stress chamber 1 and the second high-pressure stress chamber respectively, and the connecting ends of the reciprocating plunger 2 cooperate with the ball screw 12 and the pulling component respectively; the worm gear component includes a worm gear box 21 and a connecting shaft 15. The pulling component is installed on the worm gear box 21. The connecting shaft 15 is of a hollow structure, installed in the worm gear box 21, and sleeved outside the ball screw 12. Two corresponding through holes are opened at both ends of the worm gear box 21. One end of the through hole is connected to one end of the connecting shaft 15 through a thrust ball bearing 14, and a lead screw nut 16 is provided in the through hole at the other end. One end of the connecting shaft 15 is fixedly connected to the lead screw nut 16 through a bolt, so as to install the connecting shaft 15 inside the worm gear box 21.

[0049] In this embodiment, an adapter nut 13 is provided outside the through hole at one end of the worm gear box 21 corresponding to the thrust ball bearing 14; a worm gear 18 and a first tapered roller bearing 20 are also provided inside the worm gear box 21. Both the worm gear 18 and the first tapered roller bearing 20 are sleeved outside the connecting shaft 15 and are located on the side of the thrust ball bearing 14 away from the adapter nut 13; the other end of the connecting shaft 15 is fixedly connected to the worm gear box 21 through the adapter nut 13, and a worm gear adjusting washer 17 is provided between the first tapered roller bearing 20 and the thrust ball bearing 14.

[0050] In this embodiment, as Figure 1 and Figure 2 shown, the connecting end of the reciprocating plunger 2 is a T-shaped structure, including a horizontal part and a vertical part. The vertical part of the connecting end is connected to the movable end of the reciprocating plunger 2. The middle of the horizontal part of the connecting end is connected to the ball screw 12 and is positioned by a positioning pin 11; both ends of the horizontal part of the connecting end are connected with centering rings 9, and the two centering rings 9 are respectively matched with the pulling components at the upper and lower ends of the worm gear box 21; specifically, the pulling components include pull rods 10. There are two groups of pull rods 10, which are respectively arranged on the opposite sides of the worm gear box 21; the number of each group of pull rods 10 is two, and one is arranged at the upper and lower ends of the opposite sides of the worm gear box 21 respectively, so as to realize the linear reciprocating motion of the reciprocating plunger 2 on the pull rods 10.

[0051] In this embodiment, a connecting front support seat 4 is fixedly connected to the outside of the first high-pressure stress chamber 1. The connecting front support seat 4 is respectively screwed and fixed to the first high-pressure stress chamber 1 and the second high-pressure stress chamber and is locked by a locking cap 3. Both ends of the connecting front support seat 4 are matched with the pulling components; a connecting compression cap 8 is also connected to the outside of the first high-pressure stress chamber 1. The connecting compression cap 8 is located at one end of the first high-pressure stress chamber 1 close to the pulling components. A sealing ring 5, an energy storage sealing ring 6 and a guide sleeve 7 are provided inside the first high-pressure stress chamber 1. The sealing ring 5, the energy storage sealing ring 6 and the guide sleeve 7 are sequentially arranged at intervals inside the first high-pressure stress chamber 1 close to the pulling components and are located between the connecting compression cap 8 and the connecting front support seat 4. During the operation process, first, the worm 19 and the second tapered roller bearing 23 are installed at the upper end of the worm gear box 21, and the bearing gland 22 and the reducer connecting sleeve 24 are connected by bolts. Then, the reducer 26 and the worm 19 are respectively connected through a flexible coupling 25, and then the reducer 26 is key-connected to the high-speed servo motor 27; secondly, the first tapered roller bearing 20 and the hollow connecting shaft 15 are installed inside the worm gear box 21, and then the worm gear 18 is installed on the connecting shaft 15 and meshed with the worm 19. The connecting shaft 15 and the worm gear 18 are key-connected. Due to the large load, double-group flat keys are required. The worm gear adjusting washer 17, the thrust ball bearing 14 and the adapter nut 13 are installed in sequence. After connecting the above components into a whole, after the lead screw nut 16 and the ball screw 12 are installed outside, they are then installed into the connecting shaft 15 and connected by bolts, and the pull rods 10 are respectively installed at both ends of the worm gear box 21 and locked;

[0052] Threadedly connect the first high-pressure stress chamber 1 to the locking cap 3 and the connecting front support seat 4 respectively. Sequentially install the sealing ring 5, the energy storage sealing ring 6, and the guide sleeve 7 into the first high-pressure stress chamber 1. Finally, threadedly connect the connecting pressure cap 8 to the first high-pressure stress chamber 1, and install the reciprocating plunger 2 into the first high-pressure stress chamber 1. The sealing between the first high-pressure stress chamber 1 and the reciprocating plunger 2 is achieved through the energy storage sealing ring 6. It should be noted that during the installation process, the first high-pressure stress chamber and the second high-pressure stress chamber can be installed externally first;

[0053] Then install the installed first high-pressure stress chamber 1 and the second high-pressure stress chamber on the worm gear box 21. Align and install the reciprocating lead screw 4 and the flange with the 4 tie rods 10 respectively, and install the centering ring 9 between the reciprocating lead screw 4 and the flange and the tie rod 10. After installation, use the nut at the top of the tie rod 10 to form an integral body of the first high-pressure stress chamber 1, the second high-pressure stress chamber, and the worm gear box 21. Finally, adjust the locking cap 3 to fix the first high-pressure stress chamber 1 and the connecting front support seat 4 into an integral body. The installation steps of the second high-pressure stress chamber are the same as those of the first high-pressure stress chamber 1. In this embodiment, the drive control principle of the dual-system fast ultra-high-pressure tracking mechanism 9-9 is to provide a high-speed rotation speed of 6000 r / min through the high-speed servo motor 27. After being decelerated by the planetary reducer 26, it drives the worm 19 to rotate. At the same time, the worm 19 drives the circumferential movement of the worm gear 18. When the worm gear 18 rotates, it drives the connecting shaft 15 and the lead screw nut 16 to rotate. Since the lead screw nut 16 is tightly meshed and installed with the ball screw 12, the rotation of the lead screw nut 16 drives the ball screw 12 to reciprocate. Both ends of the ball screw 12 are connected to the two reciprocating plungers 2 respectively, and the two reciprocating plungers 2 are both centered by the centering ring 9. When one of the reciprocating plungers 2 moves to the left to inject high-pressure fluid into the first high-pressure stress chamber 1, at the same time, the other reciprocating plunger 2 also moves to the left to suck the liquid into the second high-pressure stress chamber. On the contrary, when the servo motor 27 rotates in reverse to control the worm 19 and the worm gear 18 to rotate in reverse, at the same time, control the lead screw nut 16 to rotate in reverse, drive the ball screw 12 and the reciprocating plunger 2 to move to the right. At this time, the first high-pressure stress chamber 1 is a low-pressure liquid suction chamber, and the second high-pressure stress chamber is a high-pressure injection chamber. A displacement sensor 10-10 is designed on the tie rod 10, and the upper and lower limits of the displacement can be set. When the reciprocating plunger 2 in the first high-pressure stress chamber 1 moves to the left to the set displacement upper limit, control the servo motor 27 to stop rotating forward and control it to rotate in reverse, so as to drive the reciprocating plunger 2 in the first high-pressure stress chamber 1 to move in the direction of the second high-pressure stress chamber. Through such repeated control, the function of rapid liquid addition under ultra-high-pressure conditions, continuous operation during this liquid addition process, pressure gradient loading during alternating stress simulation, and pressure automatic tracking is realized.

[0054] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A dual-system rapid ultra-high pressure tracking mechanism for evaluating the sealing integrity of a cement sheath, Characterized in that, Comprising: A first high-pressure stress chamber and a second high-pressure stress chamber; An adjusting device, both ends of which are respectively connected to the first high-pressure stress chamber and the second high-pressure stress chamber through pulling components, a displacement detector is arranged on the pulling component, and valve components, pressure detection components and water supply components are installed on the ends of the first high-pressure stress chamber and the second high-pressure stress chamber far away from the adjusting device through pipelines; A controller, which is electrically connected to the adjusting device, the valve component, the pressure detection component, the displacement detector and the water supply component, and the controller is used to preset the detection value of the displacement detector and control the moving distance of the adjusting device towards the first high-pressure stress chamber or the second high-pressure stress chamber according to the detection value.

2. The dual-system rapid ultra-high pressure tracking mechanism according to claim 1, Characterized in that, The adjusting device comprises a driving component, a worm gear component and a connecting component, the worm gear component is installed on the outside of the connecting component, the driving component is installed on the worm gear component, and both ends of the connecting component are movably connected to the first high-pressure stress chamber and the second high-pressure stress chamber respectively; The pulling components are installed on both sides of the worm gear component, and their ends are respectively fixedly connected to the first high-pressure stress chamber and the second high-pressure stress chamber, and the displacement detector is installed on the pulling component; The driving component is used to drive the worm gear component to drive the connecting component to perform linear reciprocating motion in the first high-pressure stress chamber or the second high-pressure stress chamber.

3. The dual-system rapid ultra-high pressure tracking mechanism according to claim 2, Characterized in that, The connecting component comprises a reciprocating plunger and a ball screw, the reciprocating plunger comprises a movable end and a connecting end, and the movable end and the connecting end are of an integral structure; The movable ends of the reciprocating plunger respectively extend into the first high-pressure stress chamber and the second high-pressure stress chamber, and the connecting ends of the reciprocating plunger are respectively matched with the ball screw and the pulling component; The worm gear component comprises a worm gear box and a connecting shaft, the pulling component is installed on the worm gear box, the connecting shaft is of a hollow structure, is installed in the worm gear box and sleeved on the outside of the ball screw, two corresponding through holes are opened at both ends of the worm gear box, one end of the through hole is connected to one end of the connecting shaft through a thrust ball bearing, a lead screw nut is arranged in the through hole at the other end, and one end of the connecting shaft is fixedly connected to the lead screw nut through a bolt.

4. The dual-system rapid ultra-high pressure tracking mechanism according to claim 3, Characterized in that, A union nut is arranged outside the through hole at one end of the worm gear box corresponding to the thrust ball bearing; A worm gear and a first tapered roller bearing are also arranged in the worm gear box, and both the worm gear and the first tapered roller bearing are also sleeved on the outside of the connecting shaft and located on the side of the thrust ball bearing away from the union nut; The other end of the connecting shaft is fixedly connected to the worm gear box through the union nut, and a worm gear adjusting washer is arranged between the first tapered roller bearing and the thrust ball bearing.

5. The dual-system rapid ultra-high pressure tracking mechanism according to claim 3, Characterized in that, The connecting end of the reciprocating plunger is of a T-shaped structure, including a horizontal part and a vertical part. The vertical part of the connecting end is connected to the movable end of the reciprocating plunger, and the middle of the horizontal part of the connecting end is connected to the ball screw and positioned by a positioning pin; Both ends of the horizontal part of the connecting end are connected with centering rings, and the two centering rings are respectively matched with the pulling components at the upper and lower ends of the worm gear box.

6. The dual-system fast ultra-high pressure tracking mechanism according to claim 3 or 5, characterized in that the pulling component includes a pull rod, and there are two groups of the pull rods, which are respectively arranged on opposite sides of the worm gear box; The number of each group of pull rods is two, and one is arranged at the upper and lower ends on opposite sides of the worm gear box.

7. The dual-system fast ultra-high pressure tracking mechanism according to claim 1, characterized in that the structures of the first high-pressure stress chamber and the second high-pressure stress chamber are the same.

8. The dual-system fast ultra-high pressure tracking mechanism according to claim 1, characterized in that A connecting front support seat is fixedly connected to the outside of the first high-pressure stress chamber and locked by a locking cap, and both ends of the connecting front support seat are matched with the pulling component.

9. The dual-system fast ultra-high pressure tracking mechanism according to claim 8, characterized in that A connecting compression cap is further connected to the outside of the first high-pressure stress chamber, and the connecting compression cap is located at one end of the first high-pressure stress chamber close to the pulling component.

10. The dual-system fast ultra-high pressure tracking mechanism according to claim 9, characterized in that A sealing retaining ring, an energy storage sealing ring and a guide sleeve are arranged in the first high-pressure stress chamber, and the sealing retaining ring, the energy storage sealing ring and the guide sleeve are sequentially arranged at intervals at one end of the first high-pressure stress chamber close to the pulling component.

Images