Gas turbine disk overspeed pre-rotation test method for both structural integrity assessment and service life extension

Abstract

The present invention belongs to the field of gas turbines, and aims to provide a gas turbine disk overspeed pre-rotation test method for both structural integrity assessment and service life extension. The method comprises the following steps: sequentially performing rotor assembly and dynamic balancing, rotor installation, an ambient-temperature trial run, temperature field calibration, a cold-state pre-rotation test and a hot-state pre-rotation test; and then performing test result validity analysis, and if criteria are met, stopping the process, and if the criteria are not met, repeating the process until the criteria are met, during which dynamic balancing criterion determination, installation criterion determination, vibration amplitude criterion determination, temperature field criterion determination, etc. are required to be performed respectively. The present invention can effectively extend the service life of disks, can reduce the production cost of the disks, and can also complete the structural integrity assessment of the disks.

Description

A method for overspeed pre-rotation test of gas turbine disk that combines structural integrity assessment and lifespan improvement Technical Field

[0001] The present invention relates to a gas turbine testing method, specifically a disk testing method. Background Technology

[0002] Modern marine and industrial gas turbines are continuously evolving towards higher power, longer lifespan, and higher reliability. To ensure sufficient strength reserves for core components, the rotating disk is typically designed to be quite thick and heavy. However, using high-performance materials in a thick disk structure significantly increases manufacturing costs. Furthermore, micro-defects within the disk cannot be detected through conventional non-destructive testing. When the unit starts up under extremely cold conditions, the low-temperature brittleness of the disk material can cause internal defects to propagate, leading to disk fracture and potentially catastrophic consequences. Therefore, designing a process testing method that can rapidly assess the structural integrity of the disk while simultaneously and effectively reducing material costs and extending the disk's lifespan is crucial.

[0003] Before installation and application, conducting high-speed pre-rotation tests on turbine disks at specific temperatures is an effective way to improve disk performance. For large, heavy gas turbine disks, in order to improve disk fatigue life while quickly detecting the disk's structural integrity, developing a suitable environmental load spectrum to coordinate the acceleration, deceleration, cooling, and heating processes of the pre-rotation test is a key aspect of the pre-rotation test. Summary of the Invention

[0004] The purpose of this invention is to provide a method for overspeed pre-rotation testing of gas turbine disks that can simultaneously and effectively reduce the material cost of the disk and improve its service life, taking into account both structural integrity assessment and life improvement.

[0005] The objective of this invention is achieved as follows:

[0006] This invention provides a method for overspeed pre-rotation testing of a gas turbine disk that simultaneously assesses structural integrity and improves service life, comprising the following steps:

[0007] (1) Perform rotor assembly and dynamic balancing;

[0008] (2) Perform dynamic balance standard judgment. If the unbalance requirement is met, proceed to step (3). If not, repeat step (1) to perform dynamic balance again.

[0009] (3) Install the rotor;

[0010] (4) Perform installation standard judgment. If the circular runout requirement is met, proceed to step (5); otherwise, proceed to step (3).

[0011] (5) Conduct a trial run at room temperature;

[0012] (6) Perform vibration amplitude standard judgment. If the vibration standard is met, proceed to step (7). If not, repeat step (1) to perform dynamic balancing again.

[0013] (7) Perform temperature field calibration;

[0014] (8) Perform a standard judgment on the temperature field. If the temperature field meets the requirements, proceed to step (9); otherwise, repeat step (7).

[0015] (9) Conduct a cold pre-rotation test;

[0016] (10) Conduct a hot pre-rotation test;

[0017] (11) Analyze the validity of the test results. If the test results meet the qualification standards, stop; otherwise, repeat step (9).

[0018] The present invention may also include:

[0019] 1. After the rotor is assembled in step (1), the diameter of the center hole or the rim is measured: at least 3 different positions are measured along the axial direction, and the diameter is measured twice at 90° perpendicular to each other at each position. These positions are marked on the wheel disk, and the average value of the measured dimensions is recorded as Dpp; and the temperature when the dimensions are measured is recorded as Ts.

[0020] 2. The dynamic balancing standard for step (2) is: the remaining unbalance after dynamic balancing is less than 100 g·mm.

[0021] 3. The installation standard for step (4) is: the circular runout of the circumference of any position of the wheel after installation is less than 0.07mm.

[0022] 4. In step (5), the rotation speed during the room temperature test run shall not exceed 70% of the normal design operating speed of the wheel. The theoretical acceleration 'a' of the test piece on the test bench is calculated using the following formula:

[0023] The acceleration during the normal temperature test rotation, cold state, and hot state pre-rotation tests shall not exceed 70% of the theoretical acceleration.

[0024] 5. The vibration amplitude standard in step (6) is: when the test piece reaches the maximum steady-state speed, the vibration amplitude of the outer edge of the rotating shaft or wheel is less than 100μm.

[0025] 6. The temperature standard for step (8) is: the absolute value of the difference between the calibrated temperature and the required temperature is less than 10℃.

[0026] 7. There are two methods for calculating the rotational speed n2 in the cold pre-rotation test:

[0027] The first method is to evaluate using the material's yield strength, and the calculation formula is as follows:

[0028] Where K is a coefficient, which is related to the disk structure and material properties;

[0029] In the formula:

[0030] σ 0.2 The yield strength at a specific temperature of 0.2%, in MPa, is the mechanical property of a specimen obtained from the high working stress region of the wheel at a specific temperature.

[0031] The second method for determining the rotational speed involves evaluating the critical defect size, α, of the wheel material. c Determined by the following formula:

[0032] In the formula: K1C is the critical stress intensity factor of the plane strain of the material, Nm-3 / 2; σ is the stress, Nm-2; Q is a constant.

[0033] 8. The calculation method for the cold pre-rotation test speed n2 is as follows:

[0034] Where K is a coefficient, which is related to the disk structure and material properties.

[0035] 9. The heat preservation time t1 before the cold pre-rotation test is at least 3 hours, and the cold pre-rotation test time t2 is at least 1 minute.

[0036] 10. The calculation method for the hot pre-rotation test speed n3 in step (10) is as follows:

[0037] and The calculation is as follows:

[0038] A, B, and C are coefficients related to the disk structure and material properties, using the mechanical properties of samples collected from the region near the central hole at a temperature of T2℃.

[0039] 11. The heat preservation time t3 before the hot pre-rotation test is at least 1 hour, and the hot pre-rotation test time t4 is at least 1 minute.

[0040] 12. If the material used for the wheel does not exhibit embrittlement within the operating temperature range, choose a room temperature pre-rotation test instead of a hot pre-rotation test, or choose a hot pre-rotation test.

[0041] 13. The calculation method for the rotational speed n3 in the aforementioned room temperature pre-rotation test is as follows:

[0042] and The calculation is as follows:

[0043] K1 and K2 are coefficients related to the disk structure and material properties, and the mechanical properties of the sample obtained from the region near the central hole are used at a temperature of 20°C.

[0044] 14. After the pre-rotation test, the wheel is cooled down. After the wheel is thermally stable, the temperature is measured. The diameter of the wheel's center hole is measured at the same position and using the same method as in step (1). The average value is recorded as Duse, and the temperature at which the size is measured is recorded as Te.

[0045] 15. The cooling rotation test T1 temperature in step (9) needs to be lower than the ductile-brittle transition temperature (DBTT) of the wheel material, and the hot rotation test T2 temperature in step (10) should be higher than the full plasticity temperature (FATT) of the wheel material.

[0046] 16. The validity analysis of the test results in step (12) consists of two parts: size detection and crack detection.

[0047] 17. Dimensional inspection: After the test, the dimensional deformation of the center hole of the wheel is equivalent to the residual strain between 500 and 2000 με. After the test, the relative change in the diameter of the wheel rim is no more than 0.08%.

[0048] 18. Crack detection involves performing non-destructive testing on the wheel after a pre-rotation test. If no cracks are found, the wheel meets the structural integrity requirements; otherwise, it is scrapped. Crack detection is divided into surface crack detection and internal crack detection. The key areas for surface crack detection are the wheel center, tenon groove, and other areas of structural stress concentration. The method used is fluorescent penetrant testing combined with magnetic particle testing, and the order of the two methods is not limited. The method for internal crack detection is high-energy X-ray testing combined with ultrasonic testing. High-energy X-ray testing is used to detect the thicker wheel center area, while ultrasonic testing is used for the wheel hub area.

[0049] 19. The difference in aperture growth should consider the following factors: If the temperature Te when measuring the size after the test differs from the temperature Ts when measuring the size before the rotation test by more than ±5℃, the thermal expansion of the wheel material should be considered to correct the diameter measurement reading. In this case, each diameter measurement value is added to the value Z: Z = αD(T s -T e )

[0050] The difference in aperture growth after correction is denoted as: Dxz = Duse - Dpp + Z.

[0051] This invention provides a method for overspeed pre-rotation testing of a gas turbine disk that simultaneously assesses structural integrity and improves service life, characterized by the following steps:

[0052] (1) Perform rotor assembly and dynamic balancing;

[0053] (2) Perform dynamic balance standard judgment. If the unbalance requirement is met, proceed to step (3). If not, repeat step (1) to perform dynamic balance again.

[0054] (3) Install the rotor;

[0055] (4) Perform installation standard judgment. If the circular runout requirement is met, proceed to step (5); otherwise, proceed to step (3).

[0056] (5) Conduct a trial run at room temperature;

[0057] (6) Perform vibration amplitude standard judgment. If the vibration standard is met, proceed to step (7). If not, repeat step (1) to rebalance.

[0058] (7) Perform temperature field calibration;

[0059] (8) Perform a standard judgment on the temperature field. If the temperature field meets the requirements, proceed to step (9); otherwise, repeat step (7).

[0060] (9) Conduct a hot pre-rotation test;

[0061] (10) Conduct a cold pre-rotation test;

[0062] (11) Analyze the validity of the test results. If the test results meet the qualification standards, stop; otherwise, repeat step (9).

[0063] The advantages of this invention are: it can effectively improve the service life of the wheel, reduce the production cost of the wheel, and at the same time complete the assessment of the structural integrity of the wheel. Attached Figure Description

[0064] Figure 1 is a flowchart of the present invention;

[0065] Figure 2 shows the overspeed pre-rotation test pattern of the gas turbine disk;

[0066] Figure 3 shows the overspeed pre-rotation test diagram of the gas turbine disk (the hot pre-rotation test was performed first, followed by the cold pre-rotation test).

[0067] In the figure: n1 is the low-speed operation during the heating and cooling process, n2 is the cold pre-rotation test speed, n3 is the hot pre-rotation test speed, T1 is the cold pre-rotation test temperature, T2 is the hot pre-rotation test temperature, t1 is the holding time before the cold pre-rotation test, t2 is the holding time of the cold pre-rotation test speed n2, t3 is the holding time before the hot pre-rotation test, and t4 is the holding time of the hot pre-rotation test speed n3. Detailed Implementation

[0068] The invention will now be described in more detail with reference to the accompanying drawings:

[0069] Referring to Figures 1-3, the present invention provides a method for overspeed pre-rotation testing of a gas turbine disk that simultaneously assesses structural integrity and improves service life, comprising the following steps:

[0070] Step 1: Perform rotor assembly and dynamic balancing, including assembling and dynamically balancing the test piece with the transfer plate, simulated blades and other test components.

[0071] After the rotor is assembled, the diameter of the center hole or the rim is measured: at least three different positions are measured along the axial direction, and the diameter is measured twice at 90° to each other at each position. These positions are marked on the wheel disk, and the average value of the measured dimensions is recorded as Dpp. The temperature at the time of measurement is also recorded as Ts.

[0072] Step 2: Perform dynamic balance standard judgment. If the unbalance requirement is met, proceed to Step 3. If not, repeat Step 1 to perform dynamic balance again.

[0073] The remaining imbalance after dynamic balancing is less than 100 g·mm.

[0074] Step 3: Install the rotor by connecting the rotor test piece to the rotating tester via an intermediate connecting fixture.

[0075] Step 4: Perform an installation standard check. If the circular runout requirement is met, proceed to Step 5; otherwise, proceed to Step 3.

[0076] The circular runout of the circumference at any position of the rear wheel is less than 0.07 mm.

[0077] Step 5: Conduct a trial run at room temperature.

[0078] The rotational speed during room temperature testing should not exceed 70% of the normal design operating speed of the wheel. The theoretical acceleration 'a' of the test piece on the test bench is calculated using the following formula:

[0079] The acceleration during the normal temperature test rotation, cold state, and hot state pre-rotation tests shall not exceed 70% of the theoretical acceleration.

[0080] Step 6: Perform a standard judgment on the vibration amplitude. If the vibration standard is met, proceed to Step 7; otherwise, repeat Step 1 to perform dynamic balancing again.

[0081] The vibration amplitude standard is: when the test piece reaches the maximum steady-state speed, the vibration amplitude of the outer edge of the rotating shaft or wheel is less than 100μm.

[0082] Step 7: Perform temperature field calibration.

[0083] Step 8: Perform a standard temperature field judgment. If the temperature field meets the requirements, proceed to step 9; otherwise, repeat step 7.

[0084] The temperature standard is: the absolute value of the difference between the calibrated temperature and the required temperature is less than 10℃.

[0085] Step 9: Conduct a cold pre-rotation test. The key parameters for this test include n2, t1, t2, and T1. Before the temperature reaches the required test temperature, the wheel should be rotated at a low speed of n1 to ensure uniform cooling.

[0086] There are two methods for calculating the rotational speed n2 in the cold pre-rotation test:

[0087] The first method is to evaluate using the material's yield strength, and the calculation formula is as follows:

[0088] Where K is a coefficient, which is related to the disk structure and material properties;

[0089] In the formula:

[0090] σ 0.2 The yield strength at a specific temperature of 0.2%, in MPa, is the mechanical property of a specimen obtained from the high working stress region of the wheel at a specific temperature.

[0091] The second method for determining the rotational speed involves evaluating the critical defect size, α, of the wheel material. c Determined by the following formula:

[0092] In the formula: K 1C The critical stress intensity factor for plane strain of the material is Nm. -3 / 2 σ represents stress, in Nm. -2 Q is a constant.

[0093] For the cold pre-rotation test, the heat preservation time t1 before the cold pre-rotation test is at least 3 hours, and the cold pre-rotation test time t2 is at least 1 minute.

[0094] During the heating and cooling process, the low-speed operating speed n1 is generally taken as 100 to 200 rpm.

[0095] The cooling rotation test temperature T1 was lower than the ductile-brittle transition temperature (DBTT) of the disk material;

[0096] Another method for calculating the cold pre-rotation test speed n2 is as follows:

[0097] Where K is a coefficient, which is related to the disk structure and material properties.

[0098] In the formula:

[0099] - Yield strength of 0.2% at 20 degrees Celsius, in MPa.

[0100] Mechanical properties of samples taken from the region near the center hole of the disc at 20°C.

[0101] For the cold pre-rotation test, the heat preservation time t1 before the cold pre-rotation test is at least 3 hours, and the rotation speed t2 of the cold pre-rotation test is at least 1 minute.

[0102] During the heating and cooling process, the low-speed operating speed n1 is generally taken as 100 to 200 rpm.

[0103] Step 10: Conduct a hot pre-rotation test. The key parameters for this test include n3, t3, t4, and T2. Before the required test temperature is reached, the wheel should be rotated at a low speed of n1 to ensure uniform heating.

[0104] The calculation method for the hot pre-rotation test speed n3 is as follows:

[0105] and The calculation is as follows:

[0106] A, B, and C are coefficients related to the disk structure and material properties, using the mechanical properties of samples collected from the region near the central hole at a temperature of T2℃.

[0107] In the formula:

[0108] - Yield strength at 0.02% of T2 degrees Celsius, in MPa.

[0109] - Yield limit of 0.2% at T2 degrees Celsius, in MPa.

[0110] - The tensile limit at T2 degrees Celsius, in MPa.

[0111] If the material used for the wheel does not exhibit embrittlement within the operating temperature range, choose a room temperature pre-rotation test instead of a hot pre-rotation test, or choose a hot pre-rotation test.

[0112] The calculation method for the rotational speed n3 in the room temperature pre-rotation test is as follows:

[0113] and The calculation is as follows:

[0114] K1 and K2 are coefficients related to the disk structure and material properties, and the mechanical properties of the sample obtained from the region near the central hole are used at a temperature of 20°C.

[0115] In the formula:

[0116] - Yield strength of 0.2% at 20 degrees Celsius, in MPa.

[0117] - Tensile limit at 20 degrees Celsius, in MPa.

[0118] The heat preservation time t3 before the hot pre-rotation test is at least 1 hour, and the hot pre-rotation test time t4 is at least 1 minute.

[0119] After the pre-rotation test, the wheel is cooled down. After the wheel is thermally stable, the temperature is measured. The diameter of the wheel's center hole is measured at the same position and using the same method as in step (1). The average value is recorded as Duse, and the temperature at which the size is measured is recorded as Te.

[0120] The temperature T2 in the hot rotation test is greater than the full plasticity temperature (FATT) of the disc material.

[0121] Step 11: Conduct a validity analysis of the test results (including two parts: dimensional inspection and crack inspection). If the test meets the qualification criteria, stop the test. If not, double-check the correct application of material data and formulas, select a new test speed, and repeat step 9 to conduct the test.

[0122] If the temperature Te when measuring the dimensions after the test differs from the temperature Ts when measuring the dimensions before the rotation test by more than ±5℃, it is necessary to consider the thermal expansion of the wheel material to correct the diameter measurement reading.

[0123] In this case, the value "Z" should be added to each diameter measurement: Z = αD(T) s -T e (10)

[0124] In the formula:

[0125] α is the coefficient of linear expansion of the material, measured in °C. -1 .

[0126] D is the nominal diameter of the disc's center hole, in mm.

[0127] Ts is the temperature at which dimensions were measured before the test, in °C.

[0128] Te represents the temperature at which dimensions were measured after the test, in °C.

[0129] The difference in aperture growth after correction is denoted as: Dxz = Duse - Dpp + Z (11)

[0130] Crack detection involves performing non-destructive testing on all surfaces of the wheel after a pre-rotation test. If no cracks are found, the wheel meets the structural integrity requirements; otherwise, the wheel is scrapped.

[0131] The order of pre-rotation tests is not fixed. The same wheel can be subjected to cold pre-rotation test first and then hot pre-rotation test. Alternatively, only one type of pre-rotation test can be performed as needed.

Claims

1. A method for overspeed pre-rotation testing of a gas turbine disk that simultaneously assesses structural integrity and improves service life, characterized by: Includes the following steps: (1) Perform rotor assembly and dynamic balancing; (2) Perform dynamic balance standard judgment. If the unbalance requirement is met, proceed to step (3). If not, repeat step (1) to perform dynamic balance again. (3) Install the rotor; (4) Perform installation standard judgment. If the circular runout requirement is met, proceed to step (5); otherwise, proceed to step (3). (5) Conduct a trial run at room temperature; (6) Perform vibration amplitude standard judgment. If the vibration standard is met, proceed to step (7). If not, repeat step (1) to perform dynamic balancing again. (7) Perform temperature field calibration; (8) Perform a standard judgment on the temperature field. If the temperature field meets the requirements, proceed to step (9); otherwise, repeat step (7). (9) Conduct a cold pre-rotation test; (10) Conduct a hot pre-rotation test; (11) Analyze the validity of the test results. If the test results meet the qualification standards, stop; otherwise, repeat step (9).

2. A method of super-speed pre-rotation test for a gas turbine disk considering structural integrity and life improvement according to claim 1, characterized in that: After the rotor is assembled in step (1), the diameter of the center hole or the rim is measured: at least three different positions are measured along the axial direction, and the diameter is measured twice at 90° to each other at each position. These positions are marked on the wheel disk, and the average value of the measured dimensions is recorded as Dpp. The temperature at the time of measurement is recorded as Ts.

3. A method of super-speed pre-rotation test for a gas turbine disk considering structural integrity and life improvement according to claim 1, characterized in that: The dynamic balancing standard for step (2) is: the remaining imbalance after dynamic balancing is less than 100 g·mm.

4. The method of claim 1, wherein the method is a super-speed pre-rotation test method for a gas turbine disk, which takes into account structural integrity and improves life, characterized in that: The installation standard for step (4) is: the circular runout of the circumference of any position of the wheel after installation is less than 0.07mm.

5. A method of super-speed pre-rotation test for a gas turbine disk considering structural integrity and life improvement according to claim 1, characterized in that: The rotating speed of the step (5) normal temperature test rotation is not more than 70% of the normal design operating rotating speed of the wheel disc, and the theoretical acceleration a of the test piece on the test table is calculated according to the following formula: The acceleration during the normal temperature test rotation, cold state, and hot state pre-rotation tests shall not exceed 70% of the theoretical acceleration.

6. A method of super-speed pre-rotation test for a gas turbine disk considering structural integrity and life improvement according to claim 1, characterized in that: The vibration amplitude standard for step (6) is: when the test piece reaches the maximum steady-state speed, the vibration amplitude of the outer edge of the rotating shaft or wheel is less than 100μm.

7. A method of super-speed pre-rotation test for a gas turbine disk considering structural integrity and life improvement according to claim 1, characterized in that: The temperature standard for step (8) is: the absolute value of the difference between the calibrated temperature and the required temperature is less than 10℃.

8. A method of super-speed pre-rotation test for a gas turbine disk considering structural integrity and life improvement according to claim 1, characterized in that: There are two methods for calculating the cold pre-rotation test speed n2: The first is to use the material yield strength to evaluate, the calculation formula is as follows: Where K is a coefficient, which is related to the disk structure and material properties; In the formula: σ 0.2 0.2% yield strength at a specific temperature, in MPa, using a specimen taken from the high working stress area of the wheel disc at the specific temperature; The second rotational speed determination method determines the critical defect size a of the wheel disc material by evaluating the critical defect size c is determined from the following formula: where: K 1C K is the plane strain critical stress intensity factor of the material, Nm -3 / 2 ; σ is the stress, Nm -2 ; Q is a constant.

9. A method of super-speed pre-rotation test for a gas turbine disk considering structural integrity and life improvement according to claim 1, characterized in that: The calculation method of the cold pre-rotation test rotating speed n2 is: Where K is a coefficient, which is related to the disk structure and material properties.

10. A method of super-speed pre-rotation test for a gas turbine disk considering structural integrity and life improvement according to claim 1, characterized in that: The heat preservation time t1 before the cold pre-rotation test is at least 3 hours, and the cold pre-rotation test time t2 is at least 1 minute.

11. A method of super-speed pre-rotation test for a gas turbine disk considering structural integrity and life improvement according to claim 1, characterized in that: The calculation method of the step (10) hot state pre-rotation test rotating speed n3 is: and The calculation is as follows: A, B, and C are coefficients related to the disk structure and material properties, using the mechanical properties of samples collected from the region near the central hole at a temperature of T2℃.

12. A method of super-speed pre-rotation test for a gas turbine disk considering structural integrity and life improvement according to claim 1, characterized in that: The heat preservation time t3 before the hot pre-rotation test is at least 1 hour, and the hot pre-rotation test time t4 is at least 1 minute.

13. The method of claim 1, wherein the method is a super-speed pre-rotation test method for a gas turbine disk, which takes into account structural integrity and improves life, characterized in that: If the material used for the wheel does not exhibit embrittlement within the operating temperature range, choose a room temperature pre-rotation test instead of a hot pre-rotation test, or choose a hot pre-rotation test.

14. A method of super-speed pre-rotation testing of a gas turbine disk for both structural integrity assessment and life improvement according to claim 13, characterized in that: The calculation method of the rotation speed n3 of the normal-temperature pre-rotation test is as follows: and The calculation is as follows: K1 and K2 are coefficients related to the disk structure and material properties, and the mechanical properties of the sample obtained from the region near the central hole are used at a temperature of 20°C.

15. A method of super-speed pre-rotation test for a gas turbine disk considering structural integrity and life improvement according to claim 1, characterized in that: After the pre-rotation test is completed, the wheel is cooled down. When the wheel is thermally stable, the temperature is measured. The diameter of the wheel's center hole is measured at the same position and using the same method as in step (1). The average value is recorded as Duse, and the temperature at which the size is measured is recorded as Te.

16. A method of super-speed pre-rotation test for a gas turbine disk considering structural integrity and life improvement according to claim 1, characterized in that: The temperature of the cooling rotation test T1 in step (9) is lower than the ductile-brittle transition temperature (DBTT) of the wheel material, and the temperature of the hot rotation test T2 in step (10) is higher than the full plasticity temperature (FATT) of the wheel material.

17. A method of super-speed pre-rotation test for a gas turbine disk considering structural integrity and life improvement according to claim 1, characterized in that: The validity analysis of the test results in step (11) consists of two parts: size detection and crack detection.

18. A method of super-speed pre-rotation testing of a gas turbine disk for both structural integrity assessment and life enhancement according to claim 17, characterized by the dimensions The test results showed that after the test, the dimensional deformation of the center hole of the wheel was equivalent to the residual strain between 500 and 2000 με, and the relative change in the diameter of the wheel rim was no more than 0.08%.

19. A method of super-speed pre-rotation testing of a gas turbine disk for both structural integrity assessment and life enhancement according to claim 17, characterized in that: Crack detection involves performing non-destructive testing on the wheel after a pre-rotation test. If no cracks are found, the wheel meets the structural integrity requirements; otherwise, it is scrapped. Crack detection is divided into surface crack detection and internal crack detection. For surface crack detection, the key areas are the wheel center, tenon groove, and other areas of structural stress concentration. The method used is a combination of fluorescent penetrant testing and magnetic particle testing, with no restriction on the order of the two methods. For internal crack detection, high-energy X-ray testing is combined with ultrasonic testing. High-energy X-ray testing is used to detect the thicker wheel center area, while ultrasonic testing is used for the wheel's fin area.

20. A method of super-speed pre-rotation testing of a gas turbine disk for both structural integrity assessment and life enhancement according to claim 18, characterized in that: The difference in aperture growth is considered in the following way: If the temperature Te at the time of dimensional measurement after the test differs from the temperature Ts at the time of dimensional measurement before the rotation test by more than ±5℃, the thermal expansion of the wheel material is considered to correct the diameter measurement reading. In this case, the value Z is added to each diameter measurement: Z = αD(T s -T e ) The difference in aperture growth after correction is denoted as: Dxz = Duse - Dpp + Z.

21. A method of super-speed pre-rotation testing of a gas turbine disk for both structural integrity evaluation and life enhancement, characterized by: Includes the following steps: (1) Perform rotor assembly and dynamic balancing; (2) Perform dynamic balance standard judgment. If the unbalance requirement is met, proceed to step (3). If not, repeat step (1) to perform dynamic balance again. (3) Install the rotor; (4) Perform installation standard judgment. If the circular runout requirement is met, proceed to step (5); otherwise, proceed to step (3). (5) Conduct a trial run at room temperature; (6) Perform vibration amplitude standard judgment. If the vibration standard is met, proceed to step (7). If not, repeat step (1) to perform dynamic balancing again. (7) Perform temperature field calibration; (8) Perform a standard judgment on the temperature field. If the temperature field meets the requirements, proceed to step (9); otherwise, repeat step (7). (9) Conduct a hot pre-rotation test; (10) Conduct a cold pre-rotation test; (11) Analyze the validity of the test results. If the test results meet the qualification standards, stop; otherwise, repeat step (9).

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