Rubber plug testing device and testing method

Abstract

The invention provides a rubber plug testing device and a testing method.The rubber plug testing device comprises a testing sleeve, a sealing plate and a first rubber plug short section, a rubber plug is arranged in the first rubber plug short section, and the first rubber plug short section is arranged at the first end of the testing sleeve and connected with the testing sleeve in a sealed mode; the first side portion of the sealing plate is sealed with the end face, away from the test sleeve, of the first rubber plug short section, and displacement liquid can enter the first rubber plug short section through the sealing plate and drive the rubber plug to move in the test sleeve in the axis direction of the rubber plug. According to the invention, the wear state and the sealing state of the rubber plug in a long-distance moving process in a casing string can be truly simulated, and guidance is provided for evaluating the sealing performance and the wear degree of the rubber plug used in an actual well completion construction process.

Description

Technical Field

[0001] The invention relates to the field of cementing plug testing, and in particular to a plug testing device and a testing method. Background Art

[0002] After drilling an oil and gas well, casing needs to be lowered for cementing operations. Rubber plugs are key components that isolate drilling fluid and cement slurry during cementing, and they play a key role in the cementing process. Existing tests mainly focus on the temperature and pressure resistance of rubber plugs. There is still a lack of corresponding testing devices for the wear resistance of rubber plugs, especially the wear resistance of the rubber plug as a whole when running long distances in the casing. With the continuous improvement of cementing technology, the wear resistance of the rubber plug as a whole is becoming more and more important. Therefore, there is an urgent need for a rubber plug testing device that can simulate downhole working conditions to verify whether the wear resistance of the rubber plug meets the requirements of cementing operations. Summary of the invention

[0003] One object of the present invention is to provide a rubber plug testing device and a testing method, so as to truly simulate the wear state and sealing state of the rubber plug during long-distance movement in a casing string, and provide guidance for evaluating the sealing performance and wear degree of the rubber plug used in the actual completion construction process.

[0004] According to the present invention, a rubber plug testing device is provided, comprising: a test sleeve, a sealing plate, and a first rubber plug short section with a rubber plug arranged therein, wherein the first rubber plug short section is arranged at a first end portion of the test sleeve and is sealed to the test sleeve, a first side portion of the sealing plate is sealed to an end surface of the first rubber plug short section away from the test sleeve, and a displacement liquid can enter the interior of the first rubber plug short section through the sealing plate and drive the rubber plug to move in the test sleeve along its axial direction.

[0005] In a preferred embodiment, the rubber plug testing device also includes a water tank, a three-way valve and a circulation pump connected to the water tank, the water tank is used to provide and collect the displacement liquid released during the test, the three-way valve is connected to the circulation pump, and the three-way valve is connected to the sealing plate.

[0006] In a preferred embodiment, the rubber plug testing device further comprises a mounting plate, the test sleeve is provided with a second rubber plug short section sealed therewith at the second end, the first side portion of the mounting plate is sealedly connected to the end face of the second rubber plug short section away from the test sleeve, the first side portion of the mounting plate is provided with a first distance sensor, the first distance sensor is communicatively connected with the three-way valve, when the rubber plug is displaced into the second rubber plug short section, the first distance sensor can identify that the rubber plug is in place and send a control signal to the three-way valve to cut off the displacement fluid flow from the three-way valve to the test sleeve and make it flow back to the water tank.

[0007] In a preferred embodiment, the second side portion of the sealing plate is connected to a hydraulic cylinder disposed on the vertical beam, and the hydraulic cylinder can drive the sealing plate to extend or retract. During the extension of the sealing plate, the first side portion of the sealing plate can be tightly sealed against the end surface of the first rubber plug short section away from the test sleeve. After the sealing plate is retracted, the first rubber plug short section can be removed.

[0008] In a preferred embodiment, the two cross beams are respectively provided with fixing claws for fixing the test sleeve.

[0009] In a preferred embodiment, the rubber plug testing device also includes a slide arranged on one side of the main body, the slide is parallel to the crossbeam and its length is greater than the crossbeam, and a manipulator is arranged on the slide, the manipulator has two jaws and can move straight along the slide, for grabbing the first rubber plug pup section and the second rubber plug pup section and positioning and installing them.

[0010] In a preferred embodiment, both ends of the first rubber plug nipple are configured with sealing bevels, and the sealing bevels can cooperate with the end surface of the test sleeve and the first side portion of the sealing plate to form a seal.

[0011] In a preferred embodiment, a heating jacket is provided on the outer surface of the test sleeve, and a heater is provided in the water tank.

[0012] The present invention also provides a rubber plug testing method, which is characterized in that it includes the following steps: S1, heating the test sleeve to the operating temperature, and at the same time heating the test liquid in the water tank to the operating temperature, starting the circulation pump, and controlling the test liquid to flow back to the water tank through the three-way valve; S2, when the test liquid temperature reaches the set value, controlling the test liquid to circulate into the first rubber plug short section through the three-way valve, and pushing the rubber plug to move along its axis in the test sleeve; S3, when the rubber plug is displaced into the second rubber plug short section, the first distance sensor on the mounting plate can recognize that the rubber plug is in place, and sends a control signal to the three-way valve to cut off the displacement liquid flow from the three-way valve to the test sleeve, and make it flow back to the water tank.

[0013] In a preferred embodiment, the rubber plug testing method further includes the following steps: S4, one of the jaws of the manipulator clamps the second rubber plug pup section and takes it out, uses the other jaw to clamp the first rubber plug pup section, and installs the second rubber plug pup section to the first end of the test sleeve, and pushes the first rubber plug pup section through the sealing plate to achieve installation sealing; the manipulator moves the first rubber plug pup section and installs it to the second end of the test sleeve, and achieves a sealed connection with the mounting plate.

[0014] The present invention has at least the following technical effects:

[0015] According to the present invention, a test casing, a sealing plate, and a first rubber plug nipple with a rubber plug disposed therein are provided. Since the first rubber plug nipple is disposed at the first end of the test casing and is sealed to the test casing, the first side portion of the sealing plate is sealed to the end face of the first rubber plug nipple away from the test casing, thereby simulating the sealing environment of the rubber plug during its movement in the casing string. Furthermore, since the displacement liquid can enter the interior of the first rubber plug nipple through the sealing plate 4 and drive the rubber plug to move in the test casing along its axial direction, the wear state and sealing state of the rubber plug during its long-distance movement in the casing string can be truly simulated, providing guidance for evaluating the sealing performance and wear degree of the rubber plug used in the actual completion construction process.

[0016] According to the present invention, the test sleeve is provided with a second rubber plug nipple sealedly connected thereto at the second end, the first side of the mounting plate is sealedly connected to the end face of the second rubber plug nipple away from the test sleeve, the first side of the mounting plate is provided with a first distance sensor, and the first distance sensor is communicatively connected to the three-way valve. When the rubber plug is displaced into the second rubber plug nipple, the first distance sensor can identify that the rubber plug is in place, and send a control signal to the three-way valve to cut off the displacement fluid flow from the three-way valve to the test sleeve, and make it flow back to the water tank, thereby avoiding high pressure after the rubber plug is in place, thereby avoiding safety accidents.

[0017] According to the present invention, one of the grippers of the manipulator grips the second rubber plug pup section and takes it out, and uses the other gripper to grip the first rubber plug pup section, and installs the second rubber plug pup section to the first end of the test sleeve, and pushes the first rubber plug pup section through the sealing plate to achieve installation sealing; the manipulator moves the first rubber plug pup section and installs it to the second end of the test sleeve, and achieves a sealing connection with the mounting plate, thereby enabling automated long-distance testing.

[0018] According to the present invention, a heating sleeve is provided on the outer surface of the test sleeve, and a heater is provided in the water tank. Before the test starts, the test sleeve is heated to the operating temperature, and the test liquid in the water tank is heated to the operating temperature. The circulation pump is turned on, and the test liquid is controlled to flow back to the water tank through a three-way valve, thereby simulating the actual temperature condition.

[0019] According to the present invention, the main body can be placed horizontally or vertically to simulate the working conditions of the downhole rubber plug running in casings with different inclinations. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The overall structural diagram of a rubber plug testing device according to an embodiment of the present invention is schematically shown.

[0021] In the present application, all drawings are schematic drawings, which are only used to illustrate the principles of the present invention and are not drawn according to the actual scale. DETAILED DESCRIPTION

[0022] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] In the description of the present invention, it should be understood that the terms "left", "right", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are 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, and therefore cannot be understood as limiting the present invention. In the present invention, "multiple" refers to two or more.

[0024] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixed" and the like 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, an electrical connection, or a communication connection; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0025] like Figure 1 As shown, the rubber plug testing device 100 of the present invention comprises: a first rubber plug short section 1, a sealing plate 4 and a test sleeve a, a rubber plug 10 is arranged inside the first rubber plug short section 1, a plurality of rubber bowls of the rubber plug 10 are in contact with the inner wall of the first rubber plug short section 1, the first rubber plug short section 1 is arranged at the first end of the test sleeve a and is sealed with the test sleeve a, the first side of the sealing plate 4 is tightly sealed with the end face of the first rubber plug short section 1 away from the test sleeve a, and the displacement liquid can enter the interior of the first rubber plug short section 1 through the sealing plate 4, and drive the rubber plug 10 to move in the test sleeve a along its axial direction. It should be noted that after the first rubber plug short section 1 is sealed and connected to the test sleeve a, the hollow spaces inside the two are connected, so as to facilitate the movement of the rubber plug 10 therein.

[0026] According to the present invention, a test casing a, a sealing plate 4, and a first rubber plug nipple 1 having a rubber plug 10 disposed therein are provided. Since the first rubber plug nipple 1 is disposed at the first end of the test casing a and is sealed to the test casing a, the first side portion of the sealing plate 4 is sealed to the end face of the first rubber plug nipple 1 away from the test casing a, thereby simulating the sealing environment of the rubber plug during movement in the casing string. Furthermore, since the displacement liquid can enter the interior of the first rubber plug nipple 1 through the sealing plate 4 and drive the rubber plug 10 to move in the test casing a along its axial direction, the wear state and sealing state of the rubber plug during long-distance movement in the casing string can be truly simulated, providing guidance for evaluating the sealing performance and wear degree of the rubber plug used in the actual completion construction process.

[0027] In one or more embodiments, the rubber plug testing device 100 of the present invention further includes a water tank 7, a three-way valve 8 and a circulation pump 9, all of which are connected to the water tank 7, and the three-way valve 8 and the circulation pump 9 are connected by a pipeline. The water tank 7 is arranged at the lower end of the main body 5 (described in detail below), and is used to provide and collect the displacement liquid released by pressure relief during the test. The three-way valve 8 is connected to the sealing plate 4 by a pipeline. Specifically, the sealing plate 4 is also provided with a threaded hole connected to the circulation pipeline, which is used to connect to the circulation pipeline so that the displacement liquid can enter the interior of the first rubber plug short section 1 through the sealing plate 4. A heater (not shown in the figure) is provided in the water tank 9, which is used to keep the test liquid medium therein warm to simulate the downhole temperature conditions.

[0028] In one or more embodiments, the test sleeve a is provided with a second rubber plug short section 12 sealed and connected thereto at its second end, the first side portion of the mounting plate b is sealed and connected to the end face of the second rubber plug short section 12 away from the test sleeve a, and a first distance sensor 6 is provided on the first side portion of the mounting plate b, and the first distance sensor 6 is communicatively connected to the three-way valve 8. When the rubber plug 10 is displaced into the second rubber plug short section 12 at the second end of the test sleeve a, the first distance sensor 6 on the mounting plate b can identify that the rubber plug 10 is in place, and send a control signal to the three-way valve 8 to cut off the displacement fluid flow from the three-way valve 8 to the test sleeve a, and make it flow back to the water tank 7, thereby avoiding high pressure after the rubber plug 10 is in place, thereby avoiding safety accidents.

[0029] In one or more embodiments, a second distance sensor 61 is provided on the first side of the sealing plate 4, and the second distance sensor 61 is communicated with the three-way valve 8. When the second distance sensor 61 detects that the rubber plug 10 is located in the left rubber plug short section 1, a control signal is sent to the three-way valve 8, thereby controlling the circulation pump 9 to pump liquid into the rubber plug short section 1 to replace the movement of the rubber plug 10.

[0030] In one or more embodiments, the rubber plug testing device 100 of the present invention further includes a main body 5, which includes two cross beams 51 arranged in parallel with the test casing a, the test casing a is arranged between the two cross beams 51, the two cross beams 51 are connected at both ends by vertical beams 52, the vertical beams 52 are arranged vertically with the cross beams 51, the second side of the sealing plate 4 is connected to one of the vertical beams 52, the second side of the mounting plate b is connected to the other vertical beam 52, and the main body 5 can be placed horizontally or vertically to simulate the working conditions of the underground rubber plug running in casings with different inclinations. During the test, the displacement liquid released by the pressure relief in the main body 5 can enter the water tank 7.

[0031] In one or more embodiments, the second side of the sealing plate 4 is connected to a hydraulic cylinder disposed on the vertical beam 52, and the hydraulic cylinder can drive the sealing plate 4 to extend or retract. During the extension of the sealing plate 4, the first side of the sealing plate 4 can be tightly sealed against the end face of the first rubber plug short section 1 away from the test sleeve a. After the sealing plate 4 is retracted, the first rubber plug short section 1 can be easily disassembled. The second side of the mounting plate b is connected to a hydraulic cylinder disposed on another vertical beam 52, and the hydraulic cylinder can drive the mounting plate b to extend or retract. During the extension of the mounting plate b, the first side of the mounting plate b can be tightly sealed against the end face of the second rubber plug short section 12 away from the test sleeve a. After the mounting plate b is retracted, the second rubber plug short section 12 can be easily disassembled.

[0032] In one or more embodiments, the two crossbeams 51 are respectively provided with fixing claws 11 for fixing the test sleeve a. The fixing claws 11 can be extended and retracted to fix the test sleeves a with different outer diameters.

[0033] In one or more embodiments, the rubber plug testing device 100 of the present invention further includes a carriage 3 disposed on one side of the main body 5. The carriage 3 is parallel to the crossbeam 51 and its length is greater than the crossbeam 51. A manipulator 2 is disposed on the carriage 3. The manipulator 2 can move linearly along the carriage 3. The manipulator 2 is used to grab the first rubber plug pup section 1 and the second rubber plug pup section 12, and position and install the first rubber plug pup section 1 and the second rubber plug pup section 12. The manipulator 2 has two clamps, which can clamp two first rubber plug pup sections 1 at the same time.

[0034] In one or more embodiments, a heating jacket (not shown) is provided on the outer surface of the test casing a to simulate downhole temperature conditions.

[0035] In one or more embodiments, the first rubber plug nipple 1 has the same structure as the second rubber plug nipple 2. Both ends of the first rubber plug nipple 1 are configured with sealing bevels, which can cooperate with the end surface of the test sleeve a and the first side of the sealing plate 4 to form a seal.

[0036] The following is combined with Figure 1The structure and working principle of the present invention are specifically described.

[0037] Before the test, the test sleeve a is installed and fixed by the fixing claws 11 on the main body 5, and a first rubber plug short section 1 is respectively provided at both ends of the test sleeve a, and a rubber plug 10 for testing is installed in the first rubber plug short section 1 at the first end, and then the first rubber plug short section 1 is pushed through the sealing plate 4 on the main body 5, so that one end surface of the first rubber plug short section 1 is pressed against the test sleeve a, and the other end surface of the first rubber plug short section 1 is pressed against the sealing structure of the sealing plate 4 to form a seal.

[0038] Based on the above-mentioned rubber plug testing device 100, the present invention further provides a rubber plug testing method, comprising the following steps:

[0039] S1. Heat the test sleeve a to the operating temperature through the heating sleeve, and at the same time heat the liquid test medium in the water tank 7 to the operating temperature through the heater, and start the circulation pump 9. At this time, the test liquid is controlled to flow back to the water tank 7 only through the three-way valve 8.

[0040] S2. When the temperature of the test liquid reaches the set value, the test liquid is controlled to circulate into the first rubber plug nipple 1 at the first end of the test casing a through the three-way valve 8, and the rubber plug 10 is pushed to move in the test casing a. It should be noted that the displacement of the circulation pump 9 is set according to the test parameters, which is used to simulate the actual operating parameters of the downhole rubber plug.

[0041] S3. When the rubber plug 10 is displaced into the second rubber plug nipple 12 at the second end of the test sleeve a, the first distance sensor 6 on the mounting plate b can recognize that the rubber plug 10 is in place, and send a control signal to the three-way valve 8 to cut off the displacement fluid flow from the three-way valve 8 to the test sleeve a, and make it flow back to the water tank 7, thereby avoiding high pressure after the rubber plug 10 is in place, thereby causing a safety accident.

[0042] The rubber plug testing method of the present invention also includes: S4, the manipulator 2 on the slide 3 moves to the right end of the slide, and one of the jaws of the manipulator 2 clamps the second rubber plug short section 12 containing the rubber plug 10 inside and takes it out. Subsequently, the manipulator 2 moves to the left end of the slide 3, and uses its other jaw to clamp the first rubber plug short section 1 located at the first end of the test sleeve a, and installs the second rubber plug short section 12 containing the rubber plug 10 to the first end of the test sleeve a, and pushes the first rubber plug short section 12 through the sealing plate 4 to achieve installation sealing. Subsequently, the manipulator 2 moves and installs the first rubber plug short section 1 to the second end of the test sleeve a, and achieves a sealing connection with the mounting plate b, thereby completing a pass test of the rubber plug 10 in the test sleeve a.

[0043] S5. According to the length of the test casing a and the total distance that the test plug 10 needs to move in the test casing a, the number of reciprocating tests of the plug 10 is calculated, and the test is automatically repeated, so as to automatically simulate the operation wear test of the plug under the underground temperature condition.

[0044] Although the present invention has been described with reference to preferred embodiments, various modifications may be made thereto and parts thereof may be replaced by equivalents without departing from the scope of the present invention. In particular, the various technical features mentioned in the various embodiments may be combined in any manner as long as there are no structural conflicts. The present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A rubber plug testing device, comprising: A test sleeve, a sealing plate, and a first rubber plug nipple with a rubber plug disposed therein, wherein the first rubber plug nipple is disposed at a first end portion of the test sleeve and is sealed to the test sleeve, a first side portion of the sealing plate is sealed to an end surface of the first rubber plug nipple away from the test sleeve, and a displacement liquid can enter the interior of the first rubber plug nipple through the sealing plate and drive the rubber plug to move in the test sleeve along its axial direction.

2. The rubber plug testing device according to claim 1, characterized in that: It also includes a water tank, a three-way valve and a circulation pump all connected to the water tank, the water tank is used to provide and collect displacement liquid released during pressure relief during the test, the three-way valve is connected to the circulation pump, and the three-way valve is connected to the sealing plate.

3. The rubber plug testing device according to claim 2, characterized in that: The test sleeve further comprises a mounting plate, wherein the second end of the test sleeve is provided with a second rubber plug short section sealed therewith, the first side of the mounting plate is sealedly connected to the end face of the second rubber plug short section away from the test sleeve, the first side of the mounting plate is provided with a first distance sensor, and the first distance sensor is communicatively connected to the three-way valve, When the rubber plug is displaced into the second rubber plug nipple, the first distance sensor can identify that the rubber plug is in place and send a control signal to the three-way valve to cut off the displacement fluid flow from the three-way valve to the test sleeve and return it to the water tank.

4. The rubber plug testing device according to claim 3, characterized in that: It also includes a main body, which includes two cross beams arranged parallel to the test sleeve, the test sleeve is arranged between the two cross beams, the two cross beams are connected at both ends by vertical beams, the vertical beams are arranged perpendicular to the cross beams, the second side portion of the sealing plate is connected to one of the vertical beams, and the second side portion of the mounting plate is connected to the other vertical beam. During the test, the displacement liquid released by the pressure relief in the main body can enter the water tank.

5. The rubber plug testing device according to claim 4, characterized in that: The second side portion of the sealing plate is connected to a hydraulic cylinder disposed on the vertical beam, and the hydraulic cylinder can drive the sealing plate to extend or retract. During the extension of the sealing plate, the first side portion of the sealing plate can be pressed tightly against the end surface of the first rubber plug short section away from the test sleeve for sealing. After the sealing plate is retracted, the first rubber plug short section can be removed.

6. The rubber plug testing device according to claim 4, characterized in that: The two cross beams are respectively provided with fixing claws for fixing the test sleeve.

7. The rubber plug testing device according to claim 4, characterized in that: It also includes a slide arranged on one side of the main body, the slide is parallel to the crossbeam and its length is greater than the crossbeam, and a manipulator is arranged on the slide. The manipulator has two clamping claws and can move straight along the slide to grab the first rubber plug short section and the second rubber plug short section and position and install them.

8. The rubber plug testing device according to claim 1, characterized in that: Both ends of the first rubber plug nipple are configured with sealing bevels, and the sealing bevels can cooperate with the end surface of the test sleeve and the first side portion of the sealing plate to form a seal.

9. The rubber plug testing device according to claim 1, characterized in that: The outer surface of the test sleeve is provided with a heating sleeve, and the water tank is provided with a heater.

10. A rubber plug testing method, characterized in that: The following steps are involved: S1. Heat the test sleeve to the working temperature, heat the test liquid in the water tank to the working temperature, start the circulation pump, and control the test liquid to flow back to the water tank through the three-way valve; S2. When the temperature of the test liquid reaches the set value, the test liquid is circulated to the first rubber plug nipple through the three-way valve, and the rubber plug is pushed to move along its axis in the test sleeve; S3. When the rubber plug is displaced into the second rubber plug nipple, the first distance sensor on the mounting plate can recognize that the rubber plug is in place and send a control signal to the three-way valve to cut off the displacement fluid flow from the three-way valve to the test casing and return it to the water tank.

11. The method for testing the rubber plug according to claim 10, further comprising the following steps: S4. One of the grippers of the manipulator grips the second rubber plug pup section and takes it out, and uses the other gripper to grip the first rubber plug pup section, and installs the second rubber plug pup section to the first end of the test sleeve, and pushes the first rubber plug pup section through the sealing plate to achieve installation sealing; the manipulator moves the first rubber plug pup section and installs it to the second end of the test sleeve, and achieves a sealed connection with the mounting plate.

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