Injection and production string elastic peristalsis simulation test device and method

Abstract

The application belongs to the field of petroleum equipment, and discloses an injection-production string elastic creep simulation test device and method, which are used for simulating the elastic creep of the injection-production string. The device comprises a sleeve and a telescopic mechanism. The sleeve comprises a main body and a scale, and the main body defines a sealed cavity. In use, the telescopic mechanism is connected with a packer, the packer can be set in the sealed cavity, the packer generates displacement in response to the pressure change in the sealed cavity and drives the telescopic mechanism to generate elastic creep, and the distance of the elastic creep can be indicated by the scale. The injection-production string elastic creep simulation test device provided by the application can simulate the elastic creep of the injection-production string, provides technical support for evaluating the performance of the packer under the influence of the elastic creep of the injection-production string, and two elastic components are arranged in the simulation test device, so that the stretching and compression states of the string can be comprehensively simulated without interference.

Description

Technical Field

[0001] This invention relates to the field of petroleum equipment, and in particular to a device and method for simulating the elastic creep of injection and production tubing. Background Technology

[0002] Implementing stable oil production and water control is a key technology in the middle and later stages of oilfield water injection development. Improving the sealing performance of packers to enable rational water injection is one of the important conditions for implementing stable oil production and water control technology. Therefore, improving the sealing performance of packers is crucial for oilfields to achieve long-term stable and high production.

[0003] When injection wells are shut down, tested, or experience pressure fluctuations, changes in tubing pressure alter the stress state of the tubing, leading to tubing creep. This creep causes the packer sleeve to move, deteriorating its working conditions and potentially causing sleeve damage, seal failure, and affecting the effective period of stratified injection. Especially under pressure fluctuations, the stress state of the tubing changes. When the upper or lower pressure is high, the tubing may stretch or compress. If the packer spacing is tight or the distance between the packer and the formation is small, the sleeve may move out of the clamping section, causing cross-contamination and resulting in stratified injection failure. Therefore, simulation tests of the elastic creep of injection and production tubing are necessary.

[0004] Patent CN104316410A discloses a compression packer rubber sleeve experimental device. The device includes a pressure-bearing cylinder, a mandrel, an upper connector, a hanger, and an extension cylinder. The pressure-bearing cylinder is a cylindrical body closed at the bottom and open at the top, with a liquid inlet hole on its outer side. The mandrel is placed inside the pressure-bearing cylinder, and the rubber sleeve and the upper connector are sleeved on the outer wall of the mandrel. The upper end of the rubber sleeve and the lower end of the upper connector are separated by a spacer ring. The upper end of the upper connector is connected to the hanger, which has cylindrical ends and a truncated cone shape in the middle. The upper end of the hanger is connected to the extension cylinder. A pressure ring is threaded onto the upper end of the mandrel, with the lower end face of the pressure ring tightly against the upper end face of the extension cylinder. A pressure cap is connected to the upper end of the extension cylinder, and a top cap is connected to the inner wall of the upper end of the pressure-bearing cylinder. The lower end face of the top cap presses against the truncated cone surface of the hanger. The extension cylinder is sleeved on the outer wall of the mandrel. This device can simulate the working process of a compression packer cartridge, including setting, unsealing, pressurizing, and packing, thus providing a reference for the selection and optimization of packers and cartridges. However, this device cannot simulate the impact on the cartridge and the damage it suffers when the tubing experiences creep.

[0005] Patent CN104374559A discloses a dynamic performance testing device for downhole tools, which includes a creep loading mechanism, an experimental fixture mechanism, and a measurement and control mechanism. The creep loading mechanism consists of a base, a loading cylinder assembly mounted on the base, a guide rail, and a trolley mounted on the guide rail, with the central axis of the base aligned with the central axis of the guide rail. The experimental fixture mechanism consists of a pressure cap, a loading short connector, a loading polished rod, a sealing sleeve, a flange joint, a variable thread joint, a test sleeve, and a blind flange. The measurement and control mechanism includes three sets of control devices and a central processing unit (CPU). Each control device includes an energy storage device, a hydraulic pump, a check valve, a pressure sensor, and a pressure relief valve. This device enables creep testing of oil and gas well tools such as packers under high-pressure downhole conditions. However, this device cannot simulate the actual working state of elastic creep in the injection and production tubing on the packer.

[0006] Therefore, there is an urgent need in this field to study a simulation test device and method for elastic creep of injection and production tubing. Summary of the Invention

[0007] To address the above problems, this invention provides a device and method for simulating the elastic creep of injection and production tubing.

[0008] According to one aspect of the present invention, an elastic creep simulation test apparatus for injection and production tubing is provided, comprising: A sleeve, the sleeve comprising a body and a scale, the body defining a sealing cavity and having an interface for adjusting the pressure within the sealing cavity, the scale being disposed on the body; A telescopic mechanism includes a central tube, a first elastic component, a limiting sleeve, a second elastic component, and a lower connector. The first elastic component, the limiting sleeve, and the lower connector are sequentially sleeved around the central tube along the axial direction. The first end of the first elastic component is fixed to the central tube, and the second end is adjacent to the limiting sleeve. The limiting sleeve and the lower connector can slide relative to the central tube within a set range. The second elastic component is sleeved on the limiting sleeve, and the first end of the second elastic component is connected to the limiting sleeve, and the second end is connected to the lower connector. In use, the lower connector is connected to the packer, which is able to set in the sealing cavity. The packer responds to pressure changes in the sealing cavity by displacement and drives the telescopic mechanism to produce elastic peristalsis. The distance of the elastic peristalsis can be indicated by the scale.

[0009] According to one embodiment of the present invention, the central tube includes a contraction portion, a transition portion, and an expansion portion arranged sequentially along the axial direction, wherein the outer diameter of the expansion portion is larger than the outer diameter of the contraction portion, and the transition portion is the connecting portion of the contraction portion and the expansion portion.

[0010] According to one embodiment of the present invention, the movement range of the limiting sleeve is limited by the transition portion, and the first elastic member is sleeved on the contraction portion.

[0011] According to one embodiment of the present invention, the transition portion is a first outer step, and the inner wall of the limiting sleeve adjacent to the first elastic member is provided with an inner step. The first outer step can prevent the inner step from moving away from the first elastic member to limit the movement range of the limiting sleeve.

[0012] According to one embodiment of the present invention, the central tube is provided with a second outer step at one end near the lower connector, and the lower connector is provided with an inner step at one end near the limiting sleeve. The second outer step cooperates with the inner step to prevent the lower connector from detaching from the central tube.

[0013] According to one embodiment of the present invention, a gap is provided between the inner wall of the lower connector and the outer wall of the central tube, a first magnetic component is provided in the gap, the first magnetic component is fixedly connected to the lower connector, and a second magnetic component is provided in the scale that magnetically engages with the first magnetic component. The second magnetic component changes the color of at least a portion of the scale in response to the movement of the first magnetic component.

[0014] According to one embodiment of the present invention, the first magnetic component is a magnetic ring, and the second magnetic component is magnetic powder.

[0015] According to one embodiment of the present invention, the scale has an indicating surface for marking graduations and a base surface opposite to the indicating surface. The indicating surface is closer to the sealing cavity than the base surface. A receiving area is defined between the indicating surface and the base surface. The receiving area is divided into a plurality of isolated partitions according to the scale graduations of the scale. Each partition is filled with magnetic powder. When the magnetic ring moves closer to the partition, the magnetic powder in the partition is attracted by magnetic force and moves to a position closer to the indicating surface, causing the area of ​​the indicating surface corresponding to the movement range of the magnetic ring to change color.

[0016] According to one embodiment of the present invention, the sleeve further includes a scale reset component, which is a magnetic strip disposed on one side adjacent to the base surface.

[0017] According to one embodiment of the present invention, the lower connector includes a tension / compression sleeve and a lower connector that can be detachably connected. The tension / compression sleeve is disposed between the limiting sleeve and the lower connector, and the lower connector is used to connect a packer.

[0018] According to one embodiment of the present invention, the inner walls of the tension sleeve and the lower connector form an inner groove, the second outer step extends into the inner groove, and the axial movement range of the tension sleeve and the lower connector is defined by two opposing side walls of the inner groove.

[0019] According to one embodiment of the present invention, the lower connector includes a connecting section and a shrinking section. The connecting section is connected to the tension sleeve. The inner diameter of the shrinking section is smaller than the inner diameter of the connecting section, such that an inner boss is formed at the connection point between the two. The inner boss restricts the range of movement of the tension sleeve and the lower connector in the direction toward the first elastic member.

[0020] According to one embodiment of the present invention, the interface of the sleeve includes an upper pressure regulating port and a lower pressure regulating port respectively disposed at both axial ends adjacent to the body.

[0021] According to one embodiment of the present invention, the simulation test apparatus further includes a pressure regulating mechanism, which is connected to the sealing cavity via the upper pressure regulating port or the lower pressure regulating port to regulate the pressure inside the sealing cavity.

[0022] According to one embodiment of the present invention, the telescopic mechanism further includes an upper connector connected to an end of the central tube and close to a first end of the first elastic member.

[0023] According to one embodiment of the present invention, the telescopic mechanism further includes a top ring disposed within the gap between the lower connector and the central tube to support the lower connector.

[0024] According to one embodiment of the present invention, the limiting sleeve includes a sleeve body and an outer flange. The outer flange is disposed at the second end of the limiting sleeve near the first elastic member, and the outer diameter of the outer flange is larger than the outer diameter of the sleeve body. The second elastic member is sleeved on the sleeve body and its end abuts against the outer flange.

[0025] According to another aspect of the present invention, a method for simulating the elastic creep of an injection-production tubing is provided. The method is implemented using the elastic creep simulation test apparatus for an injection-production tubing as described in any of the above embodiments, and the method includes the following steps: Step 1: Install the packer onto the lower connector of the telescopic mechanism, place the telescopic mechanism with the packer into the sealing cavity of the sleeve, and set the rubber sleeve of the packer in the sealing cavity; Step 2: Adjust the air pressure in the sealing cavity to change the pressure on the rubber cylinder, causing the packer to move within the sealing cavity; Step 3: After the telescopic mechanism moves with the packer and then stops elastically, the distance of the elastic creep is read using the scale.

[0026] According to one embodiment of the present invention, adjusting the air pressure within the sealing cavity to change the pressure on the rubber sleeve, thereby causing the packer to move within the sealing cavity, includes at least one of the following: Adjusting the air pressure inside the sealing cavity increases the pressure on the upper end face of the rubber cylinder, causing the packer to move downward, simulating the downward elastic creep of the injection and production tubing; Adjusting the air pressure inside the sealing cavity increases the pressure on the lower end face of the rubber tube, causing the packer to move upward, simulating the upward elastic peristalsis of the injection and production tubing.

[0027] According to one embodiment of the present invention, the method further includes: repeating steps 1 to 3 until the rubber sleeve is worn to the point that it can no longer be set, and recording the number of repetitions as the limit number of wear cycles of the packer.

[0028] According to one embodiment of the present invention, the method further includes determining the elastic parameters of the corresponding first elastic component and the second elastic component based on the parameters of the tubing to be simulated, according to the elastic modulus equivalence method, before installing the packer onto the lower connector of the telescopic mechanism.

[0029] By employing the above technical solutions, the injection-production tubing elastic creep simulation test device provided by this invention can simulate the elastic creep of the injection-production tubing, providing technical support for evaluating the performance of packers based on the elastic creep of the injection-production tubing. The simulation test device is equipped with two elastic components, which can comprehensively simulate the tensile and compressive states of the tubing without interference. The designed scale can observe the creep state of the packer and measure the movement distance, allowing for the estimation of the actual distance based on the simulated distance. Using the injection-production tubing elastic creep simulation test method of this invention, the wear limit and displacement of the packer sleeve can be determined, avoiding accidents such as packer seal failure caused by the elastic creep of the injection-production tubing, thus improving the economic efficiency of stratified injection-production. Simultaneously, the device and method of this invention can also be used to screen packers, which is beneficial for improving oil well recovery efficiency and extending the sealing operation cycle of water injection wells. Attached Figure Description

[0030] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation thereof. In the drawings: Figure 1 A schematic diagram of a simulation test apparatus for elastic creep of injection and production tubing according to an embodiment of the present invention is shown; Figure 2 A schematic diagram of the structure of a telescopic mechanism according to an embodiment of the present invention is shown; Figure 3A general flowchart of a simulation test method for elastic creep of injection and production tubing according to an embodiment of the present invention is shown.

[0031] List of reference numerals in the attached diagram: 100. Sleeve; 110. Main body; 111. Sealing cavity; 112. Interface; 112a. Upper pressure adjusting port; 112b. Lower pressure adjusting port; 120. Scale; 121. Scale reset component; 200. Telescopic mechanism; 210. Central tube; 211. Contraction section; 212. Transition section; 213. Expansion section; 214. Second outer step; 220. First elastic component; 221. First elastic component first... 222, Second end of the first elastic component; 230, Limiting sleeve; 231, First end of the limiting sleeve; 231a, Inner step; 231b, Outer flange; 232, Sleeve body; 233, Second end of the limiting sleeve; 240, Second elastic component; 250, Lower connector; 251, Tension sleeve; 252, Lower connector; 260, Upper connector; 270, First magnetic component; 280, Top ring; S, Packer. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0033] The terms "comprising" and "having," and any variations thereof, used in the specification and accompanying drawings of this invention are intended to cover non-exclusive inclusion; the terms "first," "second," etc., used in the specification, claims, or accompanying drawings of this invention are used to distinguish different objects, not to describe a particular order. "A plurality of" means two or more, unless otherwise explicitly specified.

[0034] Furthermore, the reference to "embodiment" herein means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0035] One object of the present invention is to provide a simulation test device for elastic creep of injection and production tubing. Figure 1 A schematic diagram of a simulation test apparatus for elastic creep of injection and production tubing according to an embodiment of the present invention is shown. Figure 2 A schematic diagram of a telescopic mechanism according to an embodiment of the present invention is shown. Figure 1-2As shown, the injection and production tubing elastic creep simulation test device of this embodiment generally includes a casing 100 and a telescopic mechanism 200.

[0036] The sleeve 100 mainly includes a body 110 and a scale 120. The body 110 defines a sealing cavity 111, and the body 110 is also provided with an interface 112 for adjusting the pressure inside the sealing cavity 111. The scale 120 is provided on the body 110.

[0037] The telescopic mechanism 200 mainly includes a central tube 210, a first elastic component 220, a limiting sleeve 230, a second elastic component 240, and a lower connector 250. The first elastic component 220, the limiting sleeve 230, and the lower connector 250 are sequentially sleeved around the central tube 210 along the axial direction. The first end 221 of the first elastic component 220 is fixed to the central tube 210, and the second end 222 of the first elastic component 220 is adjacent to the limiting sleeve 230. The limiting sleeve 230 and the lower connector 250 can slide relative to the central tube 210 within a set range. The second elastic component 240 is sleeved on the limiting sleeve 230, with its first end 241 connected to the limiting sleeve 230 and its second end 242 connected to the lower connector 250.

[0038] In operation, the lower connector 250 is connected to the packer S. The packer S is capable of setting within the sealing cavity 111. The packer S responds to pressure changes within the sealing cavity 111, causing displacement and elastic creep of the telescopic mechanism 200. The distance of this elastic creep can be indicated by a scale. Based on this distance and using the equivalent method of elastic modulus, the movement distance of the packer caused by the elongation or compression of the actual injection / production tubing can be calculated.

[0039] The components are described below with reference to the accompanying drawings.

[0040] The sleeve 100 serves two main functions: simulating the pressure environment of the tubing string and enabling displacement reading. For this purpose, the sleeve 100 includes a main body 110 and a scale 120. The main body 110 can be a transparent tube, with its upper and lower ends capable of being closed to form a sealed cavity 111. To facilitate the installation of the telescopic mechanism 200 and the packer S within the sealed cavity 111, the upper end of the main body 110 may have an opening, which, in conjunction with a cap, defines a chamber that can be opened or closed.

[0041] The main body 110 may also be provided with an interface 112 for adjusting the pressure within the sealing cavity 111. The interface 112 allows the sealing cavity 111 to communicate with the outside, so that the pressure within the sealing cavity 111 can be adjusted by inflating / deflating the sealing cavity 111. For example, Figure 1The main body 110 shown is provided with an upper pressure regulating port 112a and a lower pressure regulating port 112b. The upper pressure regulating port 112a is located near the upper end of the main body, and the lower pressure regulating port 112b is located near the lower end of the main body. However, the present invention is not limited thereto. The upper pressure regulating port 112a can be provided in any area above the position suitable for setting the packer S, and the lower pressure regulating port 112b can be provided in any area below the position suitable for setting the packer S.

[0042] The scale 120 can be fixedly installed on one side of the main body 110. The scale 120 is provided with graduations, which can be used to read the elastic creep distance of the telescopic mechanism 200.

[0043] like Figure 2 As shown, the telescopic mechanism 200 is used to simulate the injection and production tubing. The telescopic mechanism 200 mainly includes a central tube 210, a first elastic component 220, a limiting sleeve 230, a second elastic component 240, and a lower connecting member 250.

[0044] The outer wall of the central tube 210 can be a variable diameter structure. The variable diameter structure includes a contraction section 211, a transition section 212, and an expansion section 213 arranged sequentially along the axial direction. The outer diameter of the expansion section 213 can be larger than the outer diameter of the contraction section 211, and the transition section 212 is the connecting part between the contraction section 211 and the expansion section 213. For example... Figure 2 As shown, the upper section of the central tube 210 has a smaller outer diameter, while the lower section has a larger outer diameter, forming an outer step between the two sections. This outer step is the transition portion 212, which limits the axial movement range of the limiting sleeve 230. For example, the upper inner wall of the limiting sleeve 230 may be provided with an inner step, and the transition portion 212 can prevent the inner step from moving away from the first elastic member 220 (i.e., downwards as shown in the figure). This will be explained in detail below in conjunction with the structure of the limiting sleeve 230.

[0045] The lower end of the central tube 210 is also provided with a second outer step 214. The second outer step 214 is used to limit the axial movement range of the lower connector 250 and prevent the lower connector 250 from detaching from the central tube 210.

[0046] The first elastic component 220 is mainly used to apply pressure to the central tube 210 to simulate the compression state of the tubing. Specifically, the first elastic component 220 can be a helical spring, which can be sleeved on the contraction portion 211 of the central tube 210. The first end 221 of the first elastic component 220 can be fixedly welded to the outer wall of the central tube 210, and the second end 222 of the first elastic component 220 can move freely along the axial direction and is adjacent to the limiting sleeve 230 in the assembled state.

[0047] The limiting sleeve 230 is fitted onto the outer wall of the central tube 210. The limiting sleeve 230 includes a first end 231, a sleeve body 232, and a second end 233 arranged sequentially along the axial direction. The inner wall near the first end 231 of the limiting sleeve 230 may be provided with an inner step 231a. That is, compared with the inner wall of other parts of the limiting sleeve 230, the inner wall at the inner step 231a protrudes towards the central axis, so that the radial dimension d1 of the central hole of the limiting sleeve 230 at the inner step 231a is smaller than the dimension of the central hole of the limiting sleeve 230 in other parts, and also smaller than the outer diameter d2 of the transition part 212 of the central tube 210, so that the limiting sleeve 230 stops moving downward during the downward movement because the inner step 231a is blocked by the transition part 212. The outer wall near the first end 231 of the limiting sleeve 230 may be provided with an outer flange 231b. Compared with the outer wall of other parts of the limiting sleeve 230, the outer flange 231b has the largest outer diameter, so as to form an outer step on the outer wall of the limiting sleeve 230. This outer step can serve as a stop and connecting part of the second elastic member 240. The inner diameter of the sleeve body 232 is adapted to the expansion part 213 of the central tube 210, and its outer diameter is smaller than the outer diameter of the outer flange 231b. The sleeve body 232 extends axially for a certain distance.

[0048] The second elastic component 240 serves as a tension spring, applying tension to the injection tubing to cause the injection tubing to elastically creep downwards. Specifically, the second elastic component 240 can be a helical spring, which can be sleeved on the outer wall of the sliding sleeve 232. One end of the helical spring can be fixed to the side wall of the outer flange 231b of the limiting sliding sleeve 230, and the other end can be fixed to the upper end of the lower connector 250.

[0049] The lower connector 250 is used to connect the packer S. Specifically, the lower connector 250 may include a detachable and detachable tension sleeve 251 and a lower connector 252. The upper end of the tension sleeve 251 is close to the second end 233 of the limiting slide sleeve 230 and is fixedly connected to the lower end of the second elastic member 240. The lower end of the tension sleeve 251 is connected to the lower connector 252. An inner groove 253 is formed on the inner wall of the tension sleeve 251 and the lower connector 252, and the second outer step 214 at the lower end of the central tube 210 can extend into the inner groove 253. The inner groove 253 has two opposing radially extending sidewalls (hereinafter referred to as the upper sidewall and the lower sidewall) and an axially extending wall connecting the upper sidewall and the lower sidewall. The outer diameter of the second outer step 214 is adapted to the inner diameter of the hole portion surrounded by the axial wall and is larger than the inner diameter of the corresponding portions of the holes on the upper and lower side walls. This ensures that the lower connector 250 can not move further downward relative to the central tube 210 after it moves down to the upper side wall and abuts against the second outer step 214, and that the lower connector 250 can not move further upward relative to the central tube 210 after it moves up to the lower side wall and abuts against the second outer step 214. In other words, the lower and upper side walls constitute the upper and lower stopping points for the movement of the lower connector 250 relative to the central tube 210. In addition, a gap is left between the axial wall of the inner groove 253 and the outer wall of the central tube 210 (excluding the second outer step 214). To facilitate the installation of the packer S, the lower connector 252 may include a connecting section and a shrinking section. The connecting section is located at the upper part to connect with the tension sleeve 251, and the shrinking section is located at the lower part to assemble with the packer S. The outer diameter of the contraction section is smaller than that of the connecting section, making its outer contour suitable for assembling the packer S. The inner diameter of the contraction section is smaller than that of the connecting section, forming an inner boss at the junction of the two. The side of the inner boss can serve as the top dead center as described above.

[0050] Optionally, in some embodiments of the present invention, the telescopic mechanism 200 may further include an upper connector 260, which is connected to the upper end of the central tube 210. The upper end of the first elastic member 220 may be fixedly connected to the bottom wall of the upper connector 260, so that the first elastic member 220 can be compressed against the bottom wall of the upper connector 260, making its compression more stable.

[0051] Optionally, to facilitate reading the elastic creep distance of the tubing, the present invention also includes a related indicating component. In one specific embodiment, the indicating component includes a first magnetic component 270 and a second magnetic component. The first magnetic component 270 is disposed in the gap between the axial wall of the inner groove 253 and the outer wall of the central tube 210, and is fixedly mounted to the lower connector 252. The second magnetic component is disposed in a scale 120. Specifically, the scale 120 may have an indicating surface for marking the scale and a base surface opposite the indicating surface. The indicating surface is located on the side of the scale 120 that is easily observable and close to the sealing cavity 111. A receiving area is defined between the indicating surface and the base surface, and the receiving area is divided into multiple isolated partitions according to the scale of the scale 120. For example, when there are 100 scale lines on the scale, each two adjacent scale lines can form an independent partition, thereby forming 99 partitions. Each partition is filled with magnetic powder, and the magnetic powder in different partitions is isolated from each other. The magnetic powder can be black or colored magnetic powder. The first magnetic component 270 can be a magnetic ring. When the magnetic ring moves with the telescopic mechanism 200 closer to a section of the scale 120, the magnetic powder in the corresponding section is attracted by the magnetic force and moves closer to the indicating surface. When the magnetic powder is attracted to the indicating surface, the indicating surface reveals the color of the magnetic powder, causing the area corresponding to the movement range of the magnetic ring on the indicating surface to change color. The distance of elastic peristalsis can be read based on the range of color change during the movement. Since the packer S is fixedly connected to the lower connector 252, their movement distances are equal, and the distance of elastic peristalsis indicated by the scale 120 is approximately equal to the displacement distance of the packer S.

[0052] Optionally, in some embodiments, a scale reset component 121 is also provided within the sleeve 100 to restore the color of the indicator surface of the scale 120 to its initial color (e.g., white). Specifically, the scale reset component 121 can be a magnetic strip extending to cover the entire height of the scale, with the magnetic strip disposed on one side adjacent to the base surface. One end of the magnetic strip (shown as the upper end in the figure) can be provided with a lever. When it is desired to remove the color from the indicator surface, the magnetic strip is moved in a direction perpendicular to the length direction of the scale 120, causing the magnetic strip to sweep across the entire base surface. Since the magnetic strip has a magnetic attraction effect on the magnetic powder, the magnetic powder attracted to the vicinity of the indicator surface moves to the side closer to the base surface. As the magnetic powder moves away from the indicator surface, the color of the indicator surface disappears, restoring to its initial color.

[0053] Optionally, a top ring 280 may be provided in the gap between the axial wall of the inner groove 253 and the outer wall of the central tube 210. The top ring 280 is used to support the axial wall of the lower connector 252 in the radial direction to make it more stable, and at the same time, it can limit the movement of the first magnetic component 270.

[0054] Optionally, in some embodiments of the present invention, the injection-production tubing elastic creep simulation test apparatus may further include a pressure regulating mechanism, which is connected to the sealing cavity 111 via an upper pressure regulating port 112a or a lower pressure regulating port 112b to regulate the pressure within the sealing cavity 111. For example, the pressure regulating mechanism may be, for example, a blower.

[0055] Another object of the present invention is to provide a method for simulating the elastic creep of injection-production tubing, which is implemented using the elastic creep simulation test apparatus for injection-production tubing as described in any of the above embodiments. Figure 3 As shown, the method includes the following steps: Step 1: Install the packer S onto the lower connector 250 of the telescopic mechanism 200, place the telescopic mechanism 200 with the packer S into the sealing cavity 111 of the sleeve 100, and make the rubber sleeve of the packer S set in the sealing cavity 111. Step 2: Adjust the air pressure in the sealing cavity 111 to change the pressure on the rubber sleeve, causing the packer to move within the sealing cavity; Step 3: After the telescopic mechanism 200 moves with the packer S and elastically creeps and stops, use the scale 120 to read the distance of elastic creep.

[0056] In some embodiments, adjusting the air pressure within the sealing cavity 111 to change the pressure on the rubber sleeve, causing the packer S to move within the sealing cavity 111, includes at least one of the following: Adjust the air pressure in the sealing cavity 111 to increase the pressure on the upper end of the rubber tube, causing the packer S to move downward, simulating the downward elastic creep of the injection and production tubing; Adjust the air pressure in the sealing cavity 111 to increase the pressure on the lower end face of the rubber tube, causing the packer to move upward, simulating the upward elastic creep of the injection and production tubing.

[0057] For example, more gas can be injected into the sealing cavity 111 through the upper pressure regulating port 112a, which increases the pressure on the upper end face of the packer S rubber sleeve. The packer S moves downward under pressure, which drives the lower connector 252 to move downward. The lower connector 252 drives the tension sleeve 251 to move downward. The movement of the tension sleeve 251 causes the second elastic component 240 to stretch. The second elastic component 240 slides on the limiting sleeve 230 under force, simulating the downward elastic creep of the injection and production tubing.

[0058] Optionally, more gas can be injected into the sealing cavity 111 through the lower pressure regulating port 112b, thereby increasing the pressure acting on the lower end face of the packer S rubber sleeve. The packer S moves upward under pressure, which drives the lower connector 252 to move upward. The lower connector 252 drives the tension sleeve 251 to move upward, and applies pressure to the limiting sleeve 230 through the second elastic component 240. The limiting sleeve 230 moves upward and compresses the first elastic component 220. The first elastic component 220 is compressed and slides on the central tube 210 under force, simulating the upward elastic creep of the injection and production tubing.

[0059] Optionally, the method further includes: repeating steps 1 to 3 above until the rubber sleeve wears to the point of being unable to set, and recording the number of repetitions as the limit wear count of the packer. Optionally, the distance of each elastic creep can also be recorded, and the distances before the packer wears out can be accumulated to obtain the limit wear displacement of the packer.

[0060] Furthermore, the simulation testing apparatus of the present invention can also simulate different tubular columns by selecting appropriate first and second elastic components. To this end, in some embodiments, the simulation method further includes determining the elastic parameters of the corresponding first and second elastic components based on the parameters of the tubular column to be simulated, according to the elastic modulus equivalence method, before installing the packer onto the telescopic mechanism. Specifically, for a tubular column with known parameters, the elastic modulus E, cross-sectional area S, and length L of the tubular column are obtained. For an ideal elastic tubular column (which can be analogized to a spring), the following relationship exists: E = (F / S) / (dL / L), Where F is the load applied to the tubing, dL is the tubing deformation, E is the tubing elastic modulus, S is the tubing cross-sectional area, and L is the tubing length.

[0061] According to Hooke's Law, for elastic materials, the following relationship exists: F=K*dL (Hooke's Law) Where F is the load applied to the tubing, dL is the tubing deformation, and K is the tubing equivalent stiffness coefficient.

[0062] Based on the above two formulas, the equivalent formula for calculating the spring constant can be derived as follows: K = E * S / L.

[0063] Based on the equivalent formula for the spring stiffness coefficient described above, the spring stiffness coefficient in the simulation test device can be determined using known parameters such as the elastic modulus E, cross-sectional area S, and length L of the tubular column to be simulated, and then the corresponding simulation test can be conducted. The spring stiffness coefficients of the first and second elastic components are equal.

[0064] The embodiments described above are merely illustrative of implementation methods of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention.

Claims

1. A simulation test device for elastic creep of injection and production tubing, characterized in that, include: A sleeve (100) includes a body (110) and a scale (120), the body (110) defining a sealing cavity (111) and having an interface (112) for adjusting the pressure inside the sealing cavity (111), and the scale (120) being disposed on the body (110); Telescopic mechanism (200) includes a central tube (210), a first elastic component (220), a limiting sleeve (230), a second elastic component (240), and a lower connector (250). The first elastic component (220), the limiting sleeve (230), and the lower connector (250) are sequentially sleeved on the outside of the central tube (210) along the axial direction. The first end (221) of the first elastic component (220) is fixed to the central tube (210), and the second end (222) is adjacent to the limiting sleeve (230). The limiting sleeve (230) and the lower connector (250) can slide relative to the central tube (210) within a set range. The second elastic component (240) is sleeved on the limiting sleeve (230). The first end of the second elastic component (240) is connected to the limiting sleeve (230), and the second end is connected to the lower connector (250). In use, the lower connector (250) is connected to the packer (S), which is capable of setting in the sealing cavity (111). The packer (S) responds to pressure changes in the sealing cavity (111) and generates displacement, which drives the telescopic mechanism (200) to generate elastic peristalsis. The distance of the elastic peristalsis can be indicated by the scale (120).

2. The elastic creep simulation test device for injection and production tubing according to claim 1, characterized in that, The central tube (210) includes a contraction section (211), a transition section (212) and an expansion section (213) arranged sequentially along the axial direction. The outer diameter of the expansion section (213) is larger than the outer diameter of the contraction section (211). The transition section (212) is the connecting part of the contraction section (211) and the expansion section (213).

3. The elastic creep simulation test device for injection and production tubing according to claim 2, characterized in that, The range of movement of the limiting sleeve (230) is limited by the transition portion (212), and the first elastic member (220) is sleeved on the contraction portion (211).

4. The elastic creep simulation test device for injection and production tubing according to claim 3, characterized in that, The transition section (212) is a first outer step. The inner wall of the limiting sleeve (230) near the end (231) of the first elastic member (220) is provided with an inner step (231a). The first outer step can prevent the inner step (231a) from moving away from the first elastic member (220) to limit the movement range of the limiting sleeve (230).

5. The elastic creep simulation test device for injection and production tubing according to claim 1, characterized in that, The central tube (210) has a second outer step (214) at one end near the lower connector (250), and the lower connector (250) has an inner step at one end near the limiting sleeve (230). The second outer step (214) cooperates with the inner step to prevent the lower connector (250) from detaching from the central tube (210).

6. The elastic creep simulation test device for injection and production tubing according to claim 5, characterized in that, A gap is provided between the inner wall of the lower connector (250) and the outer wall of the central tube (210). A first magnetic component (270) is provided in the gap. The first magnetic component (270) is fixedly connected to the lower connector (250). A second magnetic component is provided in the scale (120) to magnetically engage with the first magnetic component (270). The second magnetic component changes the color of at least a portion of the scale (120) in response to the movement of the first magnetic component (270).

7. The elastic creep simulation test device for injection and production tubing according to claim 6, characterized in that, The first magnetic component (270) is a magnetic ring, and the second magnetic component is magnetic powder.

8. The elastic creep simulation test device for injection and production tubing according to claim 7, characterized in that, The scale (120) has an indicator surface with markings and a base surface opposite to the indicator surface. The indicator surface is closer to the sealing cavity (111) than the base surface. A receiving area is defined between the indicator surface and the base surface. The receiving area is divided into multiple isolated partitions according to the scale of the scale (120). Each partition is filled with magnetic powder. When the magnetic ring moves closer to the partition, the magnetic powder in the partition is attracted by magnetic force and moves to a position closer to the indicator surface, causing the area of ​​the indicator surface corresponding to the movement range of the magnetic ring to change color.

9. The elastic creep simulation test device for injection and production tubing according to claim 8, characterized in that, The sleeve (100) also includes a scale reset component (121), which is a magnetic strip disposed on one side adjacent to the base surface.

10. The elastic creep simulation test device for injection and production tubing according to claim 6, characterized in that, The lower connector (250) includes a pull-compression sleeve (251) and a lower connector (252) that can be detachably connected. The pull-compression sleeve (251) is disposed between the limiting slide sleeve (230) and the lower connector (252). The lower connector (252) is used to connect the packer (S).

11. The elastic creep simulation test device for injection and production tubing according to claim 10, characterized in that, The inner walls of the tension sleeve (251) and the lower connector (252) form an inner groove, and the second outer step (214) extends into the inner groove. The axial movement range of the tension sleeve (251) and the lower connector (252) is defined by the two opposing side walls of the inner groove.

12. The elastic creep simulation test device for injection and production tubing according to claim 11, characterized in that, The lower connector (252) includes a connecting section and a shrinking section. The connecting section is connected to the tension sleeve (251). The inner diameter of the shrinking section is smaller than the inner diameter of the connecting section, so that an inner boss is formed at the connection between the two. The inner boss restricts the range of movement of the tension sleeve (251) and the lower connector (252) in the direction toward the first elastic member (220).

13. The elastic creep simulation test device for injection and production tubing according to claim 1, characterized in that, The interface (112) of the sleeve (100) includes an upper pressure regulating port (112a) and a lower pressure regulating port (112b) respectively disposed at both axial ends adjacent to the body (110).

14. The elastic creep simulation test device for injection and production tubing according to claim 13, characterized in that, The simulation test device also includes a pressure regulating mechanism, which is connected to the sealing cavity (111) via the upper pressure regulating port (112a) or the lower pressure regulating port (112b) to regulate the pressure inside the sealing cavity (111).

15. The elastic creep simulation test device for injection and production tubing according to claim 1, characterized in that, The telescopic mechanism (200) also includes an upper connector (260) which is connected to the end of the central tube (210) and close to the first end (221) of the first elastic member (220).

16. The elastic creep simulation test device for injection and production tubing according to claim 6, characterized in that, The telescopic mechanism (200) further includes a top ring (280) disposed in the gap between the lower connector (250) and the central tube (210) to support the lower connector (250).

17. The elastic creep simulation test device for injection and production tubing according to claim 1, characterized in that, The limiting sleeve (230) includes a sleeve body (232) and an outer flange (231b). The outer flange (231b) is disposed at the second end (222) of the limiting sleeve (230) near the first elastic member (220), and the outer diameter of the outer flange (231b) is larger than the outer diameter of the sleeve body (232). The second elastic member (240) is sleeved on the sleeve body (232) and its end abuts against the outer flange (231b).

18. A method for simulating elastic creep of injection and production tubing, characterized in that, The method is implemented using the elastic creep simulation test apparatus for injection and production tubing as described in any one of claims 1-17, and the method includes the following steps: Step 1: Install the packer (S) onto the lower connector (250) of the telescopic mechanism (200), place the telescopic mechanism (200) with the packer (S) into the sealing cavity (111) of the sleeve (100) and set the rubber sleeve of the packer (S) in the sealing cavity (111); Step 2: Adjust the air pressure in the sealing cavity (111) to change the pressure on the rubber tube, causing the packer (S) to move within the sealing cavity (111); Step 3: After the telescopic mechanism (200) moves with the packer (S) and elastically creeps and stops, the distance of the elastic creep is read using the scale (120).

19. The method for simulating elastic creep of injection and production tubing according to claim 18, characterized in that, Adjusting the air pressure within the sealing cavity (111) to change the pressure on the rubber sleeve, thereby causing the packer (S) to move within the sealing cavity (111), includes at least one of the following: Adjust the air pressure in the sealing cavity (111) to increase the pressure on the upper end face of the rubber tube, causing the packer (S) to move downward, simulating the downward elastic creep of the injection and production tubing; Adjust the air pressure in the sealing cavity (111) to increase the pressure on the lower end face of the rubber tube, causing the packer (S) to move upward, simulating the upward elastic peristalsis of the injection and production tubing.

20. The method for simulating elastic creep of injection and production tubing according to claim 18, characterized in that, The method further includes: repeating steps 1 to 3 until the rubber sleeve is worn to the point that it can no longer be set, and recording the number of repetitions as the limit number of wear cycles for the packer.

21. The method for simulating elastic creep of injection and production tubing according to claim 18, characterized in that, The method further includes determining the elastic parameters of the corresponding first elastic component (220) and second elastic component (240) based on the parameters of the tubing to be simulated, using an elastic modulus equivalence method, before installing the packer onto the lower connector (250) of the telescopic mechanism (200).

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