Riser joint bending fatigue and seal test apparatus and test method

Abstract

The application discloses a kind of riser auxiliary pipe joint bending fatigue and sealing test device, sleeve is equipped on the outer periphery of pressing sleeve, and the inner wall of pressing sleeve is around at the butt joint of riser auxiliary pipe male and female joint;The counterweight unit of female joint outer port is connected with long-time pressure maintaining mechanism;The pressing unit of male joint outer port is drivingly connected with excitation unit;Strain gauge equipped on the circumference of sleeve is connected with data acquisition unit signal.The application also discloses a kind of riser auxiliary pipe joint bending fatigue and sealing test method, steps are as follows: fixing sample;Determine loading frequency and support span;Connect long-time pressure maintaining mechanism, excitation unit, data acquisition unit;Start long-time pressure maintaining mechanism, start excitation unit;By leakage and analysis test data result, bending fatigue and sealing performance are obtained.The device and method of the application provide high-frequency, periodic change bending load, and obtain the real load and fatigue life of sample.

Description

Technical Field

[0001] This invention belongs to the field of marine oil drilling and production equipment technology, and relates to a device for testing the bending fatigue and sealing of a riser auxiliary pipe joint, as well as a method for testing the bending fatigue and sealing of a riser auxiliary pipe joint. Background Technology

[0002] Deepwater drilling operations are highly risky and complex. The riser auxiliary pipe system is a pipeline system used in deepwater drilling. It plays a role in oil and gas drilling operations such as throttling, well control, and mud pressurization. The riser auxiliary pipe joint is a key component connecting the riser and the auxiliary pipe. Due to the complexity of the marine environment, factors such as ocean currents, waves, and wind can apply cyclic loads to the riser auxiliary pipe joint. These cyclic loads can cause stress concentration and stress cycling at the joint connection, resulting in fatigue damage.

[0003] To ensure that riser auxiliary pipe joints can withstand long-term cyclic loads, their sealing performance and bending fatigue life must be tested before formal deployment. This process includes testing the sealing and fatigue performance of the joint connection to assess its reliability and durability in actual use. Only through thorough testing and evaluation can the safe and reliable operation of riser auxiliary pipe joints in deep-sea drilling environments be guaranteed. Currently, there are no relevant methods and standards in China for testing the bending fatigue and sealing performance of riser auxiliary pipe joints.

[0004] Therefore, there is an urgent need to develop a new testing device for bending fatigue and sealing of auxiliary pipe joints in risers. Summary of the Invention

[0005] The purpose of this invention is to provide a bending fatigue and sealing test device for riser auxiliary pipe joints, which solves the problem that it is difficult to determine the bending fatigue and sealing performance of riser auxiliary pipe joints in non-marine platform environments using existing technologies.

[0006] Another objective of this invention is to provide a method for testing the bending fatigue and sealing performance of riser auxiliary pipe joints, which solves the problem that existing technologies struggle to determine the bending fatigue and sealing performance of riser auxiliary pipe joints in non-marine platform environments.

[0007] The technical solution adopted in this invention is a bending fatigue and sealing test device for a riser auxiliary pipe joint, comprising a pressure sleeve, a sleeve fitted around the outer circumference of the pressure sleeve, and the inner wall of the pressure sleeve surrounding the joint of the riser auxiliary pipe male joint and the riser auxiliary pipe female joint; a support unit 1 is provided on the extension section of the riser auxiliary pipe female joint, a sealing plate 1 is installed on the outer port of the riser auxiliary pipe female joint, a counterweight unit is installed on the outer end face of the sealing plate 1, and the counterweight unit is externally connected to a long-term pressure holding mechanism; a support unit 2 is provided on the extension section of the riser auxiliary pipe male joint, a sealing plate 2 is provided on the outer port of the riser auxiliary pipe male joint, a clamping unit is provided on the outer end face of the sealing plate 2, and the clamping unit is drivenly connected to the excitation unit; multiple sets of strain gauges are evenly installed on the circumference of the sleeve, and all strain gauges are signal connected to the data acquisition unit.

[0008] Another technical solution adopted in this invention is a method for testing the bending fatigue and sealing of a riser auxiliary pipe joint, which utilizes the aforementioned testing device for testing the bending fatigue and sealing of a riser auxiliary pipe joint and is implemented according to the following steps:

[0009] Step 1: Connect the male connector of the auxiliary water-proof pipe and the female connector of the auxiliary water-proof pipe together, and fix them with a compression sleeve and a sleeve to form a sample;

[0010] Step 2: Establish a finite element model of the specimen for analysis to obtain the loading frequency and support span;

[0011] Step 3: Install the specimen onto the test bench, attach the strain gauges, and connect the long-term pressure holding mechanism, excitation unit, and data acquisition unit.

[0012] Step 4: Activate the long-term pressure holding mechanism to apply internal pressure to the sample and conduct a sealing test;

[0013] Step 5: Start the excitation unit to simulate the bending conditions in actual use and conduct a bending fatigue test. Obtain the actual load and fatigue data of the specimen through the data acquisition unit.

[0014] Step 6: By detecting the leakage of the sample and analyzing the test data, the bending fatigue and sealing performance of the auxiliary pipe joint of the water-proof pipe of this sample are obtained.

[0015] The beneficial effects of this invention include the following aspects:

[0016] 1) The polarization motion of the riser auxiliary pipe joint fixed on the fatigue test bench not only realistically simulates the wave-following motion of the riser auxiliary pipe under marine drilling conditions, but also realizes the visual inspection and testing of underwater drilling equipment on land.

[0017] 2) Easy to install and simple to operate. The dynamic emergency acquisition system can monitor the alternating bending stress borne by the sample in real time.

[0018] 3) This test method can adapt to the bending fatigue and sealing performance of different types of riser pipe auxiliary pipe joints, and has strong applicability and versatility;

[0019] 4) It can quickly and accurately evaluate the bending fatigue and sealing performance of the riser auxiliary pipe joint, providing reliable reference data for users in related industries and fields to guide product design and selection, and providing a methodological guarantee for the dynamic sealing durability test of related pipes in marine equipment. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the experimental apparatus used in the method of this invention;

[0021] Figure 2 This is a partial structural schematic diagram of the experimental device of the present invention.

[0022] In the diagram, 1. Pressure sleeve, 2. Sleeve, 3. Female connector of auxiliary water riser pipe, 4. Male connector of auxiliary water riser pipe, 5. Counterweight unit, 6. Long-term pressure holding mechanism, 7. Support unit one, 8. Support unit two, 9. Clamping unit, 10. Coupling, 11. Vibration excitation unit, 12. Data acquisition unit, 13. Sealing plate one, 14. Sealing plate two, 15. Fastening screw, 16. Sealing ring. Detailed Implementation

[0023] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0024] Reference Figure 1 , Figure 2 The structure of the test device of the present invention includes a pressure sleeve 1, two sets of support units, a long-term pressure holding mechanism 6, a vibration unit 11, and a data acquisition unit 12.

[0025] A sleeve 2 is fitted around the outer periphery of the pressure sleeve 1. The pressure sleeve 1 has a split structure, and the sleeve 2 has an integral ring hub structure. The sleeve 2 is fixed to the pressure sleeve 1 as a whole by multiple fastening screws 15. The inner wall of the pressure sleeve 1 surrounds the joint of the male connector 4 and the female connector 3 of the auxiliary water pipe. The male connector 4 and the female connector 3 of the auxiliary water pipe are joined together and are called the male and female connectors of the auxiliary water pipe. At least two sealing rings 16 are provided on the splicing surface of the male connector 4 and the female connector 3 of the auxiliary water pipe. Both sealing rings 16 are installed in the sealing groove of the inner wall of the female connector 3 of the auxiliary water pipe.

[0026] The extension section of the auxiliary female connector 3 of the riser pipe is equipped with a support unit 7. Figure 1(Left side) A sealing plate 13 is installed on the outer end of the auxiliary pipe of the riser pipe 3. A counterweight unit 5 is installed on the outer end face of the sealing plate 13 to prevent the sample from tipping over. The counterweight unit 5 is connected to a long-term pressure holding mechanism 6, which can apply pressure to the inside of the male and female joints of the auxiliary pipe of the riser pipe to test the sealing reliability of the joint.

[0027] The extension section of the auxiliary pipe connector 4 is equipped with support unit 2 8 ( Figure 1 On the right side), the outer end of the male connector 4 of the water-proof pipe auxiliary pipe is provided with a sealing plate 2 14, and the outer end face of the sealing plate 2 14 is provided with a clamping unit 9. The clamping unit 9 is connected to the excitation unit 11 through the coupling 10. The excitation unit 11 can provide the water-proof pipe auxiliary pipe connector sample with a high frequency and periodic bending load.

[0028] Multiple strain gauges are evenly installed on the circumference of sleeve 2. All strain gauges are connected to the data acquisition unit 12 to obtain the true load history of the sample. The bending fatigue life of the male and female joints of the water-proof pipe and auxiliary pipe is obtained through subsequent calculations.

[0029] Support unit 7 and support unit 8 are axially adjustable. Based on the finite element analysis results, a reasonable support span is determined.

[0030] The working principle of this invention is as follows: The male connector 4 and female connector 3 of the riser auxiliary pipe to be tested are joined together and fixed into a sample using a pressure sleeve 1 and a sleeve 2. This sample is then fixed on the support unit of the resonant bending fatigue test bench. During the test, a long-term pressure-holding mechanism 6 applies internal pressure to the sample, and an alternating bending load is applied to the sample via a vibration unit 11. The vibration controller adjusts the magnitude of the vibration force through a frequency converter. To obtain accurate test data, a data acquisition unit 12 (dynamic emergency acquisition) continuously collects and outputs data and dynamically monitors the alternating bending stress borne by the sample in real time during the test. The output data mainly includes information such as strain range, number of loading cycles, and internal pressure. By analyzing and evaluating the test data, the bending fatigue and sealing performance of the riser auxiliary pipe joint are determined. These data and results can provide important references for the design and improvement of riser pipe joints, thereby improving their reliability and durability, and providing strong support for research and application in related fields.

[0031] The method for testing the bending fatigue and sealing of the auxiliary pipe joint of the riser pipe of the present invention is implemented according to the following steps using the above-mentioned testing device for testing the bending fatigue and sealing of the auxiliary pipe joint of the riser pipe:

[0032] Step 1: Prepare a set of auxiliary pipe joints for the riser pipe to be tested. Connect the male connector 4 and the female connector 3 of the auxiliary pipe together and fix them with the pressure sleeve 1 and the sleeve 2 to form a sample.

[0033] Step 2: Establish a finite element model of the specimen and analyze it to obtain the first bending vibration mode of the specimen. The analysis results will yield the loading frequency of the specimen and the support span on the test bench.

[0034] Step 3: Install the specimen onto the test bench, adjust the support span to ensure the coaxiality of the specimen and the power end, and the levelness of the specimen to visually appear horizontal; after adjustment, attach the strain gauges, and connect the long-term pressure holding mechanism 6, the excitation unit 11, and the data acquisition unit 12, see [link to relevant documentation]. Figure 1 ;

[0035] Step 4: Activate the long-term pressure holding mechanism 6 to apply internal pressure to the sample and conduct a sealing test;

[0036] Step 5: Start the excitation unit 11 to apply a certain bending force and periodic load to the sample to simulate the bending conditions in actual use and conduct bending fatigue test. Obtain the real load and fatigue data of the sample through the data acquisition unit 12.

[0037] Step 6: By detecting the leakage of the sample and analyzing the test data, the bending fatigue and sealing performance of the auxiliary pipe joint of the riser pipe are obtained.

[0038] Example 1

[0039] An experiment was conducted on a certain type of auxiliary pipe joint for a riser pipe. The outer diameter of the auxiliary pipe was 127 mm, the sample length was 9550 mm, and the support span was 5960 mm. The bending fatigue and sealing test device for the auxiliary pipe joint of the riser pipe was used, and the following steps were followed:

[0040] Step 1: Prepare a set of auxiliary pipe connectors for the riser pipe to be tested. Connect the male connector 4 and the female connector 3 of the riser pipe together and fix them with the pressure sleeve 1 and the sleeve 2 to form a sample.

[0041] Step 2: Establish a finite element model of the specimen and analyze it to obtain the first-order bending vibration mode of the specimen. The analysis results will yield the loading frequency of the specimen and the support span on the test bench.

[0042] Step 3: Install the specimen onto the test bench and adjust the support span to ensure that the coaxiality of the specimen and the power end, and the levelness of the specimen, reach the visual level.

[0043] After adjustment, attach the strain gauges, and connect the long-term pressure holding mechanism 6, the excitation unit 11, and the data acquisition unit 12. (See attached diagram.) Figure 1 .

[0044] Step 4: Start the long-term pressure holding mechanism 6 to apply internal pressure to the sample. The water pressure for starting the long-term pressure holding mechanism 6 is 10.1 MPa, and a sealing test is conducted.

[0045] Step 5: Start the excitation unit 11. The excitation frequency of the excitation unit 11 is 5.8Hz. Apply a certain bending force and periodic load to the specimen to simulate the bending conditions in actual use and conduct a bending fatigue test. Obtain the actual load and fatigue data of the specimen through the data acquisition unit 12.

[0046] Step 6: By detecting the leakage of the sample and analyzing the test data, the bending fatigue and sealing performance of the auxiliary pipe joint of the riser are obtained, and the data is recorded in Table 1 below.

[0047] Table 1. Test record data of Example 1

[0048] The total number of test cycles was 813,936. Sealing performance No leakage Fatigue performance No cracks

[0049] Analysis of the test data revealed that the bending fatigue life of the auxiliary pipe joint of this type of riser pipe is 813,936 cycles, and the sealing performance meets the technical requirements.

[0050] Example 2

[0051] An experiment was conducted on a certain type of auxiliary pipe joint for a riser pipe. The outer diameter of the auxiliary pipe was 127 mm, the sample length was 8950 mm, and the support span was 5730 mm. The bending fatigue and sealing test device for the auxiliary pipe joint of the riser pipe was used, and the following steps were followed:

[0052] Step 1: Prepare a set of auxiliary pipe connectors for the riser pipe to be tested. Connect the male connector 4 and the female connector 3 of the riser pipe together and fix them with the pressure sleeve 1 and the sleeve 2 to form a sample.

[0053] Step 2: Establish a finite element model of the specimen and analyze it to obtain the first-order bending vibration mode of the specimen. The analysis results will yield the loading frequency of the specimen and the support span on the test bench.

[0054] Step 3: Install the specimen onto the test bench, adjust the support span to ensure the coaxiality of the specimen and the power end, and the levelness of the specimen to visually appear horizontal; after adjustment, attach the strain gauges, and connect the long-term pressure holding mechanism 6, the excitation unit 11, and the data acquisition unit 12, see [link to relevant documentation]. Figure 1 .

[0055] Step 4: Start the long-term pressure holding mechanism 6 to apply internal pressure to the sample. The water pressure for starting the long-term pressure holding mechanism 6 is 10.4 MPa, and a sealing test is conducted.

[0056] Step 5: Start the excitation unit 11. The excitation frequency of the excitation unit 11 is 3.5Hz. Apply a certain bending force and periodic load to the specimen to simulate the bending conditions in actual use and conduct a bending fatigue test. Obtain the actual load and fatigue data of the specimen through the data acquisition unit 12.

[0057] Step 6: By detecting leakage in the test samples and analyzing the test data, the bending fatigue and sealing performance of the auxiliary pipe joint of the riser pipe are determined. The recorded data is shown in Table 2 below.

[0058] Table 2. Test record data of Example 2

[0059] The total number of test cycles was 1,311,321. Sealing performance No leakage Fatigue performance No cracks

[0060] Analysis of the test data revealed that the bending fatigue life of the auxiliary pipe joint of this type of water-proof pipe is 1,311,321 cycles, and the sealing performance meets the technical requirements.

[0061] Example 3

[0062] An experiment was conducted on a certain type of auxiliary pipe joint for a riser pipe. The outer diameter of the auxiliary pipe was 127 mm, the sample length was 8750 mm, and the support span was 5590 mm. The bending fatigue and sealing test device for the auxiliary pipe joint of the riser pipe was used, and the following steps were followed:

[0063] Step 1: Prepare a set of auxiliary pipe connectors for the riser pipe to be tested. Connect the male connector 4 and the female connector 3 of the riser pipe together and fix them with the pressure sleeve 1 and the sleeve 2 to form a sample.

[0064] Step 2: Establish a finite element model of the specimen and analyze it to obtain the first-order bending vibration mode of the specimen. The analysis results will yield the loading frequency of the specimen and the support span on the test bench.

[0065] Step 3: Install the specimen onto the test bench, adjust the support span to ensure the coaxiality of the specimen and the power end, and the levelness of the specimen to visually appear horizontal; after adjustment, attach the strain gauges, and connect the long-term pressure holding mechanism 6, the excitation unit 11, and the data acquisition unit 12, see [link to relevant documentation]. Figure 1 .

[0066] Step 4: Start the long-term pressure holding mechanism 6 to apply internal pressure to the sample. The water pressure for starting the long-term pressure holding mechanism 6 is 10.1 MPa, and a sealing test is conducted.

[0067] Step 5: Start the excitation unit 11. The excitation frequency of the excitation unit 11 is 3.1Hz. Apply a certain bending force and periodic load to the specimen to simulate the bending conditions in actual use and conduct a bending fatigue test. Obtain the actual load and fatigue data of the specimen through the data acquisition unit 12.

[0068] Step 6: By detecting the leakage of the sample and analyzing the test data, the bending fatigue and sealing performance of the auxiliary pipe joint of the water-proof pipe are obtained, and the data is recorded in Table 3 below.

[0069] Table 3. Test record data of Example 3

[0070] The cumulative number of test cycles was 928,749. Sealing performance No leakage Fatigue performance No cracks

[0071] Analysis of the test data revealed that the bending fatigue life of the auxiliary pipe joint of this type of water-proof pipe is 928,749 cycles, and the sealing performance meets the technical requirements.

Claims

1. A device for testing the bending fatigue and sealing of a water-supporting pipe joint, characterized in that, Includes a pressure sleeve (1), with a sleeve (2) fitted around the outer periphery of the pressure sleeve (1), and the inner wall of the pressure sleeve (1) surrounding the joint of the male connector (4) and the female connector (3) of the auxiliary pipe of the water-proof pipe; the extension section of the female connector (3) of the auxiliary pipe of the water-proof pipe is provided with a support unit (7), the outer port of the female connector (3) of the auxiliary pipe of the water-proof pipe is provided with a sealing plate (13), the outer end face of the sealing plate (13) is provided with a counterweight unit (5), and the counterweight unit (5) is connected to a long-term pressure holding mechanism (6); the extension section of the male connector (4) of the auxiliary pipe of the water-proof pipe is provided with a support unit (8), the outer port of the male connector (4) of the auxiliary pipe of the water-proof pipe is provided with a sealing plate (14), the outer end face of the sealing plate (14) is provided with a pressing unit (9), and the pressing unit (9) is connected to the excitation unit (11) for transmission; multiple strain gauges are evenly installed on the circumference of the sleeve (2), and all strain gauges are connected to the data acquisition unit (12) for signal transmission; The pressure sleeve (1) is a split structure, and the sleeve (2) is an integral ring hub structure. The sleeve (2) is fixed to the pressure sleeve (1) as a whole by multiple fastening screws (15). The long-term pressure holding mechanism (6) applies pressure to the male and female joints of the auxiliary pipe of the riser pipe to test the sealing reliability of the joint. The excitation unit (11) provides a high-frequency, periodically changing bending load for the auxiliary pipe joint sample of the water-proof pipe. The male connector (4) and female connector (3) of the riser pipe are provided with at least two sealing rings (16), and the two sealing rings (16) are installed in the sealing groove on the inner wall of the female connector (3).

2. A method for testing the bending fatigue and sealing of a riser auxiliary pipe joint, utilizing the testing apparatus for testing the bending fatigue and sealing of a riser auxiliary pipe joint as described in claim 1, characterized in that... Follow these steps: Step 1: Connect the male connector (4) and the female connector (3) of the auxiliary pipe of the riser pipe together and fix them with the pressure sleeve (1) and the sleeve (2) to form a sample; Step 2: Establish a finite element model of the specimen for analysis to obtain the loading frequency and support span; Step 3: Install the specimen on the test bench, attach the strain gauge, and connect the long-term pressure holding mechanism (6), the excitation unit (11), and the data acquisition unit (12). Step 4: Activate the long-term pressure holding mechanism (6) to apply internal pressure to the sample and conduct a sealing test; Step 5: Start the excitation unit (11) to simulate the bending conditions in actual use and conduct bending fatigue test. Obtain the real load and fatigue data of the sample through the data acquisition unit (12). Step 6: By detecting the leakage of the sample and analyzing the test data, the bending fatigue and sealing performance of the auxiliary pipe joint of the water-proof pipe of this sample are obtained.

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