Method and device for controlling assembly stress to prevent rupture of medium voltage rotor seal vane

Abstract

This invention discloses a method and device for controlling assembly stress to prevent fracture of the sealing blades of a medium-pressure rotor, belonging to the field of turbine maintenance technology. The method includes: inspecting and measuring the dimensions of the sealing blades and blade root slots to establish a dimensional database; matching based on the database to control the single-sided assembly gap between the sealing blade and the blade root slot within 0.02mm to 0.05mm; optimizing the stress at the blade root of the sealing blade; assembling the sealing blade into the blade root slot using a non-impact loading method; eliminating the generated assembly stress after assembly; and finally verifying the assembled rotor. This invention, through precise control throughout the entire process, eliminates the risk of fracture, contributing to improved blade service life and unit operational reliability.

Description

Technical Field

[0001] This invention belongs to the field of steam turbine maintenance technology, specifically relating to an assembly stress control method and device for preventing the breakage of the sealing blades of the intermediate-pressure rotor. Background Technology

[0002] The sealing blades of the last stage and the second-last stage of the intermediate-pressure rotor of a steam turbine are the locking and positioning blades of the entire stage blades. Their structure has stress concentration and harsh service conditions, making them high-incidence areas for blade fracture defects.

[0003] In existing maintenance processes, the assembly of sealing blades relies heavily on the experience of maintenance personnel, lacking quantified assembly standards and systematic stress control. For example, traditional assembly commonly uses manual hammering, which not only easily causes hidden damage at the blade root but also fails to precisely control the assembly gap. When the assembly gap between the blade and the blade root slot is too small, the blade assembly is too tight, generating significant residual compressive stress; conversely, when the assembly gap is too large, the blade lacks sufficient constraint within the blade root slot, making it prone to micro-flutter during unit operation, leading to high-frequency alternating vibration fatigue damage. Furthermore, the blade root transition fillet area of ​​the sealing blade itself has geometric stress concentration. The residual stress generated during assembly will superimpose with the alternating stress under unit operating conditions, easily initiating fatigue cracks in the blade root transition area, ultimately leading to blade fracture. This results in a high failure recurrence rate, seriously affecting the safety and stability of unit operation. Summary of the Invention

[0004] In order to overcome the shortcomings of the prior art, the present invention aims to provide an assembly stress control method and device for preventing the fracture of the sealing blade of a medium-pressure rotor, so as to solve the problems of lack of quantitative standards for sealing blade assembly, easy impact damage during assembly, unreasonable gap matching, and fatigue fracture at the blade root caused by the superposition of assembly residual stress and operating stress.

[0005] To achieve the above objectives, the present invention employs the following technical solution: In a first aspect, the present invention provides an assembly stress control method for preventing the breakage of sealing blades on a medium-pressure rotor. The method includes: cleaning and non-destructive testing of the sealing blades and blade root grooves of the rotor, measuring the blade root thickness of the sealing blades and the groove size of the blade root opening, and establishing a dimensional database; matching the sealing blades and blade root grooves based on the dimensional database, wherein the single-sided assembly gap between the sealing blades and the blade root grooves falls within a first gap range of 0.02mm to 0.05mm; performing stress optimization treatment on the blade root of the sealing blades; assembling the sealing blades into the matching blade root grooves using a non-impact loading method; eliminating the assembly stress generated during the assembly process after the sealing blades are assembled; and verifying the assembled rotor to confirm the assembly accuracy and uniformity of the entire stage of blades.

[0006] Furthermore, the aforementioned stress optimization treatment includes at least one of the following: finely grinding and finishing the root transition radius of the sealing blade, finely grinding and finishing the inlet and outlet edges of the sealing blade, and shot peening the surface layer of the sealing blade root.

[0007] Furthermore, the aforementioned non-impact loading method is a hydraulic progressive jacking assembly method.

[0008] Furthermore, the above method also includes: real-time monitoring of assembly resistance during the assembly process of the sealing blade.

[0009] Furthermore, the above-mentioned stress relief treatment for assembly generated during the assembly process includes: using a low-temperature aging vibration stress relief process to relieve the assembly stress generated during the assembly process.

[0010] Furthermore, the above-mentioned verification of the assembled rotor confirms the assembly accuracy and uniformity of the entire stage blades, including: performing low-speed turning tests on the rotor to verify the concentricity, flatness and gap uniformity of the entire stage blades.

[0011] Secondly, the present invention also provides an assembly stress control device for preventing the breakage of sealing blades of a medium-pressure rotor. The device includes: a pre-processing unit, a matching unit, a stress treatment unit, an assembly unit, and a verification unit. The pre-processing unit is used to clean and perform non-destructive testing on the sealing blades and blade root grooves of the rotor, and to measure the blade root thickness and the groove size of the blade root opening, establishing a dimensional database. The matching unit is used to match the sealing blades with the blade root grooves based on the dimensional database, wherein the single-sided assembly gap between the sealing blades and the blade root grooves falls within a first gap range of 0.02mm to 0.05mm. The stress treatment unit is used to perform stress optimization treatment on the blade root of the sealing blades. The assembly unit is used to assemble the sealing blades into the matched blade root grooves using a non-impact loading method. The stress treatment unit is also used to eliminate the assembly stress generated during the assembly process after the sealing blades are assembled. The verification unit is used to verify the assembled rotor to confirm the assembly accuracy and uniformity of the entire stage of blades.

[0012] Furthermore, the aforementioned stress treatment unit is specifically used for at least one of the following: finely grinding and finishing the blade root transition fillet of the sealing blade, finely grinding and finishing the steam inlet and steam outlet edges of the sealing blade, and shot peening the surface layer of the blade root of the sealing blade.

[0013] Furthermore, the aforementioned non-impact loading method is a hydraulic progressive jacking assembly method.

[0014] Furthermore, the aforementioned assembly unit is also used to monitor the assembly resistance in real time during the assembly process of the sealing blade.

[0015] Furthermore, the aforementioned stress treatment unit is also used to eliminate assembly stress generated during the assembly process by employing a low-temperature aging vibration stress relief process.

[0016] Furthermore, the aforementioned verification unit is specifically used to: perform low-speed turning tests on the rotor to verify the concentricity, flatness, and gap uniformity of the entire stage of blades.

[0017] Compared with the prior art, the present invention has the following beneficial effects: 1. By establishing and matching a dimensional database, the single-sided assembly gap between the sealing blade and the blade root groove is precisely controlled within the first gap range of 0.02mm to 0.05mm. This solves the problem of the lack of quantitative standards in traditional assembly, avoiding excessive assembly stress due to too small a gap and flutter fatigue damage to the blade during operation due to too large a gap. 2. By adopting a non-impact loading method (such as hydraulic progressive jacking) for assembly, impact damage and latent cracks in the blade root caused by traditional sledgehammering are avoided, effectively protecting the integrity of the blade substrate structure and improving assembly quality. 3. Through stress optimization and assembly stress elimination treatment, on the one hand, the stress distribution of the blade root is optimized and its fatigue resistance is improved before assembly through grinding and shot peening; on the other hand, residual stress generated during assembly is eliminated after assembly through processes such as low-temperature aging vibration. This avoids the superposition of residual stress and operating stress, significantly reducing the risk of fatigue crack initiation in the blade root. 4. By verifying the assembled rotor, the assembly accuracy and uniformity of the entire stage of blades were ensured, providing a guarantee for the high-speed and stable operation of the rotor. This establishes a closed-loop standardized process system from dimensional inspection and clearance matching to impact-free assembly, stress relief, and verification. This system can improve the problem of fatigue fracture in the sealing blades, helping to extend the service life of the blades and enhance the reliability of the unit operation. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is one of the flowcharts of an assembly stress control method for preventing the breakage of the sealing blades of a medium-pressure rotor provided by the present invention; Figure 2 This is the second flowchart of an assembly stress control method for preventing breakage of sealing blades of a medium-pressure rotor provided by the present invention; Figure 3This is a schematic diagram of the assembly stress control device for preventing the breakage of the sealing blades of a medium-pressure rotor provided by the present invention. Figure 4 This is one of the hardware structure diagrams of an electronic device provided by the present invention; Figure 5 This is the second schematic diagram of the hardware structure of an electronic device provided by the present invention. Detailed Implementation

[0020] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0021] It should be noted that the terms "first," "second," etc., used in this specification are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0022] The assembly stress control method and device for preventing the breakage of the sealing blades of the medium-pressure rotor provided by the present invention will be described in detail below with reference to the accompanying drawings, through specific embodiments and application scenarios.

[0023] The assembly stress control method for preventing the breakage of the sealing blades of the intermediate-pressure rotor provided by the present invention can be applied to the clearance control and residual stress management of the sealing blades of the last stage and the second last stage of the intermediate-pressure rotor of a thermal power unit.

[0024] The assembly stress control method for preventing the breakage of the sealing blades of a medium-pressure rotor provided by this invention can be implemented by an assembly stress control device for preventing the breakage of the sealing blades of a medium-pressure rotor. Exemplarily, this assembly stress control device can be an electronic device or a component within that electronic device, such as an integrated circuit or a chip. The assembly stress control method for preventing the breakage of the sealing blades of a medium-pressure rotor provided by this invention will be described exemplarily below using an electronic device as an example.

[0025] This invention provides an assembly stress control method to prevent breakage of the sealing blades of a medium-pressure rotor. Figure 1 A flowchart of an assembly stress control method for preventing breakage of the sealing blades of a medium-pressure rotor, provided by the present invention, is shown. This method can be applied to electronic devices. Figure 1 As shown, the assembly stress control method for preventing the breakage of the sealing blades of the medium-pressure rotor provided by the present invention may include the following steps 101 to 106.

[0026] Step 101: Clean and perform non-destructive testing on the sealing blades and blade root grooves of the rotor, and measure the blade root thickness and the groove size of the blade root opening to establish a dimensional database.

[0027] In some embodiments of the present invention, the sealing blade can refer to the locking and positioning blade in the turbine rotor stage blades. Its function is to axially limit and circumferentially lock the stage blades, and it is a critical part of the structure with the most significant stress concentration and the most severe service conditions. It can be understood that during the operation of the turbine, it is subjected to the combined effects of centrifugal force, aerodynamic excitation force, and thermal stress.

[0028] In some embodiments of the present invention, the blade root groove can refer to a slot structure provided on the turbine rotor disk for accommodating and fixing the blade root. It is understood that its geometry, dimensional accuracy, and surface condition directly affect the installation stability and stress distribution of the blade.

[0029] In some embodiments of the present invention, before assembly, the sealing blades, adjacent blades and rotor blade root grooves can be cleaned and non-destructively inspected to identify original cracks and defects.

[0030] Specifically, the sealing blades of the medium-pressure rotor, adjacent assembled blades, and rotor blade root grooves can be cleaned as a whole to remove surface oxide scale, burrs, and protrusions and bumps, so as to remove impurities such as oxide scale and oil stains that affect dimensional measurement. The blade root body and rounded transition area can be inspected by penetrant testing and ultrasonic testing to confirm that there are no original crack defects, thus avoiding the installation of components with initial damage into the unit.

[0031] In some embodiments of the present invention, after non-destructive testing, the blade root thickness and groove fit dimensions can be accurately measured to establish a size database of a single set of blades and corresponding blade root grooves.

[0032] Understandably, by establishing a dimensional database, the initial state of every component involved in the assembly can be fully grasped, and physical dimensions can be converted into digital information, providing a data foundation for subsequent scientific matching and solving the problem of blind assembly based solely on experience and lacking data support in existing technologies.

[0033] Step 102: Match the sealing blades with the blade root grooves based on the size database.

[0034] Among them, the single-sided assembly gap between the sealing blade and the blade root groove belongs to the first gap range, which is 0.02mm~0.05mm.

[0035] In some embodiments of the present invention, based on a measured dimensional database, the sealing blades and rotor blade root slots can be graded and matched for assembly, and the single-sided assembly gap between the sealing blades and the blade root slots can be strictly controlled to be between 0.02mm and 0.05mm.

[0036] It should be noted that by controlling the assembly gap between the sealing blade and the blade root groove on one side to be between 0.02mm and 0.05mm, the problems of excessive assembly tightness and excessive residual compressive stress caused by an assembly gap of less than 0.02mm can be avoided, as well as the problems of insufficient blade constraint and operational flutter fatigue caused by an assembly gap of more than 0.05mm.

[0037] In other words, by controlling the single-sided assembly gap between the sealing blade and the blade root groove to be between 0.02mm and 0.05mm, it can be ensured that the blade can be effectively fixed to avoid harmful fretting wear and chatter during operation, while also preventing excessive and harmful residual compressive stress due to interference fit.

[0038] In this way, by establishing a size database to match the sealing blades and blade root grooves, we can no longer rely on manual experience for matching. The abstract feel is transformed into precise values, realizing quantitative matching. This step solves the problem of uncontrollable matching accuracy in traditional processes and lays the foundation for subsequent low-stress assembly.

[0039] Step 103: Perform stress optimization treatment on the leaf root of the sealing blade.

[0040] In some embodiments of the present invention, stress optimization treatment can be performed on the blade root of the sealing blade before assembly to improve the stress condition of this inherently stress-concentrated area of ​​the sealing blade.

[0041] It is understandable that since geometrically discontinuous parts such as the blade root transition fillet are stress concentration points, their stress concentration coefficient can be reduced through proactive stress optimization, thereby improving their fatigue resistance and compensating for any deficiencies that may exist in the blade design and manufacturing stages, and further enhancing their ability to resist fatigue failure.

[0042] In some embodiments of the present invention, the stress optimization treatment described above may include at least one of the following: finely grinding and finishing the root transition fillet of the sealing blade, finely grinding and finishing the inlet and outlet edges of the sealing blade, and shot peening the surface layer of the sealing blade root.

[0043] It should be noted that the purpose of fine grinding and finishing is to unify the curvature of the root transition arc, eliminate microscopic geometric abrupt changes such as tool marks and sharp corners, and make the curvature of the leaf root transition area smoother and more uniform, thereby significantly reducing the geometric stress concentration factor in this area. Shot peening strengthens the leaf root by bombarding the surface layer with high-speed micro-shots, causing it to undergo plastic deformation, thereby introducing a layer of considerable residual compressive stress on the surface layer, which can effectively offset the tensile stress generated during operation and inhibit the initiation and propagation of fatigue cracks.

[0044] Thus, by combining the two specific methods mentioned above, the blade root can be strengthened from two dimensions: geometry and material surface properties, thereby improving its resistance to fatigue fracture.

[0045] Step 104: Assemble the sealing blade into the matching blade root groove using a non-impact loading method.

[0046] In some embodiments of the present invention, the aforementioned non-impact loading method can refer to a method of assembling blades that avoids the use of sledgehammers or other methods that generate instantaneous and uncontrollable impact forces. Its purpose is to push the blade into the blade root groove with a controllable, stable, and gradual force, thereby fundamentally preventing the generation of latent microcracks or material structure damage caused by impact in the high-stress area at the blade root.

[0047] Understandably, the traditional sledgehammer-driven assembly method generates instantaneous and enormous impact loads, which can easily cause microscopic cracks or internal material damage that are invisible to the naked eye in the stress concentration areas at the blade root. These latent damages constitute serious potential hazards and can rapidly expand into macroscopic cracks during unit operation.

[0048] In this way, by using a non-impact loading method, the blade is pushed into the slot with a smooth and controllable force, ensuring that the blade material structure is not damaged during the assembly process, thus helping to protect the integrity of the blade matrix.

[0049] In some embodiments of the present invention, the above-mentioned non-impact loading method can be a hydraulic progressive jacking assembly method.

[0050] Understandably, hydraulic systems can provide smooth, powerful, and precisely controllable thrust. Therefore, by using tools such as hydraulic jacks, the sealing blades can be pushed into the blade root groove at a very slow and uniform speed, avoiding impact. Moreover, the magnitude and speed of the loading force are adjustable and controllable throughout the process, achieving truly flexible assembly.

[0051] In some embodiments of the present invention, during the assembly process using hydraulic progressive jacking, a composite assembly method combining copper rod-assisted tapping can be used to push the sealing blade in at a uniform and slow speed.

[0052] In this way, by adopting hydraulic progressive jacking, the problem of uncontrollable magnitude and direction of impact force in traditional processes is solved, enabling precise control of the assembly process and protecting the blades to the greatest extent.

[0053] In some embodiments of the present invention, the assembly stress control method for preventing the breakage of the sealing blades of the medium-pressure rotor provided by the present invention may further include the following step 107.

[0054] Step 107: Monitor the assembly resistance in real time during the assembly of the sealing blades.

[0055] In some embodiments of the present invention, the assembly resistance is a direct reflection of the tightness of the fit between the blade and the blade root groove. Therefore, a resistance-displacement curve can be plotted in real time by installing a pressure sensor or force sensor on the jacking device. The shape of this curve can then reflect whether the assembly process is smooth and whether there are any abnormalities such as jamming or sudden increases in resistance.

[0056] In some embodiments of the present invention, a resistance threshold can be set, and if abnormal resistance is detected, the assembly can be paused for inspection to avoid damage caused by forced assembly.

[0057] Thus, this real-time monitoring method provides an additional quality control tool for non-impact assembly, improving the scientific nature and reliability of the assembly process.

[0058] Step 105: After the sealing blades are assembled, the assembly stress generated during the assembly process is eliminated.

[0059] Understandably, even under precise clearance matching and non-impact loading conditions, the assembly process will inevitably introduce some residual stress. These residual stresses will superimpose with the operating stresses of the unit (alternating stresses caused by centrifugal force, aerodynamic force, etc.) during operation, accelerating the initiation and propagation of fatigue cracks.

[0060] Therefore, by adding a special stress relief process, these harmful internal stresses can be actively eliminated, allowing the blades to return to a near-stress-free relaxed state, thus providing sufficient safety margin to withstand subsequent working loads and improving their fatigue life.

[0061] In some embodiments of the present invention, combined with Figure 1 ,like Figure 2 As shown, step 105 above may specifically include step 105a as described below.

[0062] Step 105a: After the sealing blades are assembled, a low-temperature aging vibration stress relief process is used to eliminate the assembly stress generated during the assembly process.

[0063] In some embodiments of the present invention, the low-temperature aging vibration stress relief process refers to an advanced process that, under low-temperature or room-temperature conditions without altering the metallographic structure of the workpiece or causing thermal deformation, applies a periodic excitation force of specific frequency and amplitude to the workpiece. Utilizing the resonance effect of the material, microscopic plastic deformation is induced within the material, thereby efficiently releasing and homogenizing residual internal stress generated during assembly, welding, and machining processes. Compared to traditional thermal aging treatment, it features energy saving, high efficiency, no oxidation, and no deformation.

[0064] In other words, by using the low-temperature aging vibration stress relief process, the dislocation movement inside the metal can be activated by vibration energy, which can cause the residual stress field to redistribute and reach a lower steady-state level.

[0065] In this way, without changing the metallographic structure and mechanical properties of the blade, residual tensile stress generated during assembly can be effectively eliminated, or harmful tensile stress can be transformed into beneficial compressive stress. This solves the fatal problem of the superposition of residual stress and working stress, and achieves a deep guarantee for the service safety of the blade.

[0066] Step 106: Verify the assembled rotor to confirm the assembly accuracy and uniformity of the entire stage blades.

[0067] In some embodiments of the present invention, by verifying the assembled rotor, it can be ensured that the final result of the entire assembly process meets the design requirements.

[0068] In some embodiments of the present invention, through systematic review, potential problems such as assembly misalignment and uneven gaps can be identified and corrected, ensuring that the entire blade as a whole has good dynamic characteristics, avoiding abnormal vibration of the entire rotor system caused by local assembly problems, and ensuring the reliability of the entire process and the final effect.

[0069] In some embodiments of the present invention, step 106 may specifically include step 106a as described below.

[0070] Step 106a: Perform low-speed rotating test on the rotor to verify the concentricity, flatness and gap uniformity of the entire stage blades.

[0071] In some embodiments of the present invention, low-speed turning test refers to, after the rotor assembly is completed, driving the rotor to rotate at an extremely low speed (usually a few revolutions per minute) using a dedicated turning device or manually, while simultaneously using high-precision measuring tools (such as dial indicators, laser displacement sensors, etc.) against key positions such as the blade tip or blade shroud, continuously measuring the radial runout (to assess concentricity) and axial runout (to assess flatness) during one rotation, as well as the clearance between the blade and other stationary components, thereby systematically verifying the assembly accuracy and geometric uniformity of the entire blade stage. Furthermore, by comparing whether the runout of all blades is within the allowable tolerance range (e.g., the radial runout difference of the entire blade stage is less than 0.05 mm), the uniformity of the assembly can be accurately assessed.

[0072] In this way, by performing low-speed rotating tests on the rotor, defects such as local bulges and assembly misalignment can be detected, ensuring that the vibration amplitude of the blades is stable during high-speed rotor operation and that there are no hidden dangers of abnormal vibration, thus fundamentally avoiding vibration problems caused by uneven assembly.

[0073] The following section provides a detailed explanation of the assembly stress control method for preventing the breakage of the sealing blades of the medium-pressure rotor provided by the invention, using a specific implementation scenario as an example.

[0074] Suppose that in a turbine overhaul project, the last-stage blades of the intermediate-pressure rotor of a certain unit need to be replaced. First, the blades and blade root slots can be cleaned and subjected to non-destructive testing. Workers can use specialized cleaning agents and tools to thoroughly remove oil, scale, and impurities from the new end-cap blades to be assembled, adjacent blades, and the corresponding blade root slots on the rotor body. Then, magnetic particle testing or penetrant testing is used to perform a 100% surface crack inspection on the blade root of each end-cap blade, especially the transition fillet area. Simultaneously, an ultrasonic flaw detector is used to check for metallurgical defects inside the blade root. After confirming that all blades and blade root slots are free of original defects, a coordinate measuring machine is used to accurately measure the tenon thickness of the blade root of each end-cap blade, and an inside micrometer is used to measure the slot width of each blade root slot. All measurement data is recorded and entered into a computer to establish a dimensional database containing unique numbers and corresponding dimensions.

[0075] Next, based on the established dimensional database, the single-sided assembly clearance (i.e., half the difference between the slot width and the blade root thickness) for all blade-slot pairings is calculated. Valid pairing schemes with clearance values ​​between 0.02mm and 0.05mm are selected, and a detailed assembly list is generated, clearly indicating which numbered blade should be installed in which numbered slot. This method replaces the traditional method of relying on technicians to perform trial fittings using feeler gauges and experience, achieving a scientific and precise match.

[0076] Before formal assembly, the sealing blades to be assembled are removed according to the assembly list. Workers use fine sanding belts and polishing wheels to lightly and evenly grind and polish the transition rounded corners of the blade root, the roots of the steam inlet and outlet edges, ensuring a smooth surface free of any tiny sharp corners or machining marks. Subsequently, the blades are sent to the shot peening chamber for shot peening to strengthen the blade root area. This step improves the fatigue resistance of the blade root.

[0077] Next, the process moves to a non-impact, progressive, precision assembly stage. Unlike traditional hammer-based processes, a small hydraulic jacking device is used on-site. The matched sealing blade is initially placed into the blade root slot, and then the hydraulic jack's jack rod is aligned with the blade root. The operator starts the hydraulic pump, slowly increasing the pressure, and the hydraulic jack rod pushes the blade smoothly into the slot at a uniform speed of approximately 0.5 mm / s. Pressure sensors installed on the hydraulic lines transmit real-time resistance data to a display screen, allowing the operator to monitor the resistance curve throughout the process, ensuring it is smooth and without abrupt changes. Once the blade is in place, loading is stopped.

[0078] After the blades are assembled, a low-temperature aging vibration stress relief device can be installed on the rotor, and the vibrator can be fixed at an appropriate position on the shaft. The device is started, and the resonant frequency of the rotor-blade system is found by frequency sweeping. Then, vibration is applied to the entire blade stage for approximately 20-30 minutes near this frequency. The vibration energy effectively releases and homogenizes the residual stress generated during assembly due to compression.

[0079] Finally, the assembled and processed rotor is mounted on a dedicated turning machine. Multiple dial indicators are fixed above and to the side of the rotor, with their heads contacting the top and side of the sealing blade and adjacent blades, respectively. The turning machine is started, causing the rotor to rotate slowly at 2 revolutions per minute. Workers record and analyze the dial indicator readings, calculating the radial runout (concentricity), end face runout (flatness), and blade clearance uniformity of the entire stage of blades. Only after confirming that all indicators are within allowable tolerances is the assembly considered complete. This closed-loop control throughout the entire process helps ensure the assembly quality of the sealing blades and effectively prevents root fatigue fracture failures during subsequent operation.

[0080] Each of the above-described method embodiments, or various possible implementations of each method embodiment, can be executed individually or in combination of any two or more. The specific implementation can be determined according to actual usage requirements, and the present invention does not impose any restrictions on this.

[0081] The assembly stress control method for preventing the breakage of the sealing blades of a medium-pressure rotor provided by this invention can be implemented by an assembly stress control device for preventing the breakage of the sealing blades of a medium-pressure rotor. This invention uses the assembly stress control device for preventing the breakage of the sealing blades of a medium-pressure rotor as an example to illustrate the assembly stress control device for preventing the breakage of the sealing blades of a medium-pressure rotor provided by this invention.

[0082] Figure 3 A schematic diagram of a possible structure of the assembly stress control device for preventing breakage of the sealing blades of a medium-pressure rotor, as described in this invention, is shown. Figure 3 As shown, the assembly stress control device 30 for preventing the breakage of the sealing blades of the medium-pressure rotor may include: a pre-processing unit 31, a matching unit 32, a stress processing unit 33, an assembly unit 34, and a verification unit 35.

[0083] The pre-processing unit 31 is used to clean and perform non-destructive testing on the sealing blades and blade root grooves of the rotor, and to measure the blade root thickness and the groove size of the blade root opening to establish a dimensional database. The matching unit 32 is used to match the sealing blades and blade root grooves based on the dimensional database. The single-sided assembly gap between the sealing blades and the blade root grooves belongs to the first gap range, which is 0.02mm~0.05mm. The stress treatment unit 33 is used to perform stress optimization treatment on the blade root of the sealing blades. The assembly unit 34 is used to assemble the sealing blades into the matching blade root grooves using a non-impact loading method. The stress treatment unit 33 is also used to eliminate the assembly stress generated during the assembly process after the sealing blades are assembled. The verification unit 35 is used to verify the assembled rotor to confirm the assembly accuracy and uniformity of the entire stage of blades.

[0084] In one possible implementation, the stress treatment unit 33 is specifically used for at least one of the following: finely grinding and finishing the root transition fillet of the sealing blade, finely grinding and finishing the steam inlet and steam outlet roots of the sealing blade, and shot peening the surface layer of the sealing blade root.

[0085] In one possible implementation, the aforementioned non-impact loading method is a hydraulic progressive jacking assembly method.

[0086] In one possible implementation, the assembly unit 34 is also used to monitor the assembly resistance in real time during the assembly of the sealing blade.

[0087] In one possible implementation, the stress treatment unit 33 is further used to eliminate assembly stress generated during the assembly process by employing a low-temperature aging vibration stress relief process.

[0088] In one possible implementation, the aforementioned verification unit 35 is specifically used to: perform low-speed turning detection on the rotor to verify the concentricity, flatness, and gap uniformity of the entire stage of blades.

[0089] This invention provides an assembly stress control device to prevent fracture of the sealing blade of a medium-pressure rotor. 1. By establishing and matching a dimensional database, the single-sided assembly gap between the sealing blade and the blade root groove is precisely controlled within a first gap range of 0.02mm to 0.05mm. This solves the problem of the lack of quantitative standards in traditional assembly, avoiding excessive assembly stress due to too small a gap, and flutter fatigue damage to the blade during operation due to too large a gap. 2. By adopting a non-impact loading method (such as hydraulic progressive jacking) for assembly, the impact damage and latent cracks in the blade root caused by traditional sledgehammering are avoided, effectively protecting the integrity of the blade substrate structure and improving assembly quality. 3. Through stress optimization and assembly stress elimination treatment, on the one hand, the stress distribution of the blade root is optimized and its fatigue resistance is improved by grinding and shot peening before assembly; on the other hand, residual stress generated during assembly is eliminated by low-temperature aging vibration and other processes after assembly, thereby avoiding the superposition of residual stress and operating stress and significantly reducing the risk of fatigue crack initiation in the blade root. 4. By verifying the assembled rotor, the assembly accuracy and uniformity of the entire stage of blades were ensured, providing a guarantee for the high-speed and stable operation of the rotor. This establishes a closed-loop standardized process system from dimensional inspection and clearance matching to impact-free assembly, stress relief, and verification. This system can improve the problem of fatigue fracture in the sealing blades, helping to extend the service life of the blades and enhance the reliability of the unit operation.

[0090] The assembly stress control device for preventing the breakage of the medium-pressure rotor sealing blades in this invention can be an electronic device or a component within an electronic device, such as an integrated circuit or a chip. This electronic device can be a terminal or other devices besides a terminal. For example, the electronic device can be a mobile phone, tablet computer, laptop computer, PDA, in-vehicle electronic device, mobile internet device (MID), augmented reality (AR) / virtual reality (VR) device, robot, wearable device, ultra-mobile personal computer (UMPC), netbook, or personal digital assistant (PDA), etc. It can also be a server, network attached storage (NAS), personal computer (PC), television (TV), ATM, or self-service machine, etc. This invention does not impose specific limitations.

[0091] The assembly stress control device for preventing breakage of the sealing blades of the medium-pressure rotor in this invention can be a device with an operating system. This operating system can be Android, iOS, or other possible operating systems; this invention does not specifically limit it.

[0092] The assembly stress control device for preventing the breakage of the sealing blades of the medium-pressure rotor provided by the present invention can realize the various processes implemented in the above-described embodiments of the assembly stress control method for preventing the breakage of the sealing blades of the medium-pressure rotor, and achieve the same technical effect. To avoid repetition, it will not be described again here.

[0093] Optionally, such as Figure 4 As shown, the present invention also provides an electronic device 400, including a processor 401 and a memory 402. The memory 402 stores a program or instructions that can run on the processor 401. When the program or instructions are executed by the processor 401, they implement the various steps of the above-described assembly stress control method embodiment for preventing the breakage of the sealing blade of the medium-pressure rotor, and can achieve the same technical effect. To avoid repetition, they will not be described again here.

[0094] It should be noted that the electronic devices in this invention include the mobile electronic devices and non-mobile electronic devices described above.

[0095] Figure 5 A schematic diagram of the hardware structure of an electronic device for implementing the present invention.

[0096] The electronic device 500 includes, but is not limited to, components such as: radio frequency unit 501, network module 502, audio output unit 503, input unit 504, sensor 505, display unit 506, user input unit 507, interface unit 508, memory 509, and processor 510.

[0097] Those skilled in the art will understand that the electronic device 500 may also include a power supply (such as a battery) for supplying power to various components. The power supply may be logically connected to the processor 510 through a power management system, thereby enabling functions such as managing charging, discharging, and power consumption through the power management system. Figure 5 The electronic device structure shown does not constitute a limitation on the electronic device. The electronic device may include more or fewer components than shown, or combine certain components, or have different component arrangements, which will not be elaborated here.

[0098] The processor 510 is used to clean and perform non-destructive testing on the sealing blades and root grooves of the rotor, and to measure the root thickness of the sealing blades and the groove size of the root grooves to establish a dimensional database; and to match the sealing blades and root grooves based on the dimensional database, wherein the single-sided assembly gap between the sealing blades and root grooves falls within a first gap range of 0.02mm to 0.05mm; to perform stress optimization treatment on the root of the sealing blades; to assemble the sealing blades into the matching root grooves using a non-impact loading method; to eliminate the assembly stress generated during the assembly process after the sealing blades are assembled; and to verify the assembled rotor to confirm the assembly accuracy and uniformity of the entire stage of blades.

[0099] In one possible implementation, the processor 510 is specifically used for at least one of the following: finely grinding and finishing the root transition fillet of the sealing blade, finely grinding and finishing the steam inlet and steam outlet roots of the sealing blade, and shot peening the surface layer of the sealing blade root.

[0100] In one possible implementation, the aforementioned non-impact loading method is a hydraulic progressive jacking assembly method.

[0101] In one possible implementation, the processor 510 is also used to monitor assembly resistance in real time during the assembly of the sealing blade.

[0102] In one possible implementation, the processor 510 is further used to eliminate assembly stress generated during the assembly process by employing a low-temperature aging vibration stress relief process.

[0103] In one possible implementation, the processor 510 is specifically used to: perform low-speed turning detection on the rotor to verify the concentricity, flatness, and gap uniformity of the entire stage of blades.

[0104] This invention provides an electronic device. 1. By establishing and matching a dimensional database, the single-sided assembly gap between the sealing blade and the blade root groove is precisely controlled within a first gap range of 0.02mm to 0.05mm. This solves the problem of the lack of quantitative standards in traditional assembly, avoiding excessive assembly stress due to too small a gap, and flutter fatigue damage to the blade during operation due to too large a gap. 2. By adopting a non-impact loading method (such as hydraulic progressive jacking) for assembly, the impact damage and latent cracks in the blade root caused by traditional sledgehammering are avoided, effectively protecting the integrity of the blade substrate structure and improving assembly quality. 3. Through stress optimization and assembly stress elimination treatment, on the one hand, the stress distribution of the blade root is optimized and its fatigue resistance is improved before assembly through grinding and shot peening; on the other hand, residual stress generated during assembly is eliminated after assembly through processes such as low-temperature aging vibration. This avoids the superposition of residual stress and operating stress, significantly reducing the risk of fatigue crack initiation in the blade root. 4. By verifying the assembled rotor, the assembly accuracy and uniformity of the entire stage of blades were ensured, providing a guarantee for the high-speed and stable operation of the rotor. This establishes a closed-loop standardized process system from dimensional inspection and clearance matching to impact-free assembly, stress relief, and verification. This system can improve the problem of fatigue fracture in the sealing blades, helping to extend the service life of the blades and enhance the reliability of the unit operation.

[0105] It should be understood that, in this invention, the input unit 504 may include a graphics processing unit (GPU) 5041 and a microphone 5042. The GPU 5041 processes image data of still images or videos obtained by an image capture device (such as a camera) in video capture mode or image capture mode. The display unit 506 may include a display panel 5061, which may be configured in the form of a liquid crystal display, an organic light-emitting diode, or the like. The user input unit 507 includes at least one of a touch panel 5071 and other input devices 5072. The touch panel 5071 is also called a touch screen. The touch panel 5071 may include two parts: a touch detection device and a touch controller. Other input devices 5072 may include, but are not limited to, physical keyboards, function keys (such as volume control buttons, power buttons, etc.), trackballs, mice, and joysticks, which will not be described in detail here.

[0106] The memory 509 can be used to store software programs and various data. The memory 509 may primarily include a first storage area for storing programs or instructions and a second storage area for storing data. The first storage area may store the operating system, application programs or instructions required for at least one function (such as sound playback, image playback, etc.). Furthermore, the memory 509 may include volatile memory or non-volatile memory, or both. The non-volatile memory may be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), or flash memory. The volatile memory can be random access memory (RAM), static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDRSDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous linked dynamic random access memory (SLDRAM), and direct memory bus RAM (DRRAM). The memory 509 in this invention includes, but is not limited to, these and any other suitable types of memory.

[0107] Processor 510 may include one or more processing units; optionally, processor 510 integrates an application processor and a modem processor, wherein the application processor mainly handles operations involving the operating system, user interface, and applications, and the modem processor mainly handles wireless communication signals, such as a baseband processor. It is understood that the aforementioned modem processor may also not be integrated into processor 510.

[0108] The present invention also provides a readable storage medium storing a program or instructions that, when executed by a processor, implement the various processes of the above-described assembly stress control method embodiment for preventing breakage of the sealing blades of a medium-pressure rotor, and achieve the same technical effect. To avoid repetition, these will not be described again here.

[0109] The processor mentioned above is the processor in the electronic device described in the above embodiments. The readable storage medium includes computer-readable storage media, such as computer read-only memory (ROM), random access memory (RAM), magnetic disk, or optical disk. The present invention also provides a chip, which includes a processor and a communication interface. The communication interface is coupled to the processor. The processor is used to run programs or instructions to implement the various processes of the above embodiments of the assembly stress control method for preventing fracture of the sealing blades of the medium-pressure rotor, and can achieve the same technical effect. To avoid repetition, it will not be described again here.

[0110] It should be understood that the chip mentioned in this invention may also be referred to as a system-on-a-chip, system chip, chip system, or system-on-a-chip, etc.

[0111] This invention provides a computer program product stored in a storage medium. The program product is executed by at least one processor to implement the various processes of the assembly stress control method embodiment for preventing the breakage of the sealing blade of the intermediate-pressure rotor as described above, and can achieve the same technical effect. To avoid repetition, it will not be described again here.

[0112] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. Furthermore, it should be noted that the scope of the methods and apparatuses in the embodiments of the present invention is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

[0113] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, can be embodied in the form of a computer software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal (which may be a mobile phone, computer, server, or network device, etc.) to execute the methods described in the various embodiments of the present invention.

[0114] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of this invention.

Claims

1. A method for controlling assembly stress to prevent breakage of sealing blades on a medium-pressure rotor, characterized in that, include: The sealing blades and blade root grooves of the rotor are cleaned and subjected to non-destructive testing. The root thickness of the sealing blades and the groove size of the blade root grooves are measured, and a dimensional database is established. Based on the size database, the sealing blade and the blade root groove are matched. The single-sided assembly gap between the sealing blade and the blade root groove belongs to the first gap range, which is 0.02mm~0.05mm. The leaf root of the sealing blade is subjected to stress optimization treatment; The sealing blade is assembled into the matching blade root groove using a non-impact loading method; After the sealing blades are assembled, the assembly stress generated during the assembly process is eliminated. The assembled rotor is checked and verified to confirm the assembly accuracy and uniformity of the entire stage of blades.

2. The method according to claim 1, characterized in that, The stress optimization treatment includes at least one of the following: rounding the blade root transition of the sealing blade, fine grinding and finishing the steam inlet and steam outlet edges of the sealing blade, and shot peening the surface of the blade root of the sealing blade.

3. The method according to claim 1, characterized in that, The non-impact loading method is a hydraulic progressive jacking assembly method.

4. The method according to claim 1, characterized in that, The method further includes: The assembly resistance is monitored in real time during the assembly of the sealing blade.

5. The method according to any one of claims 1 to 4, characterized in that, The process of eliminating assembly stress generated during assembly includes: Low-temperature aging vibration stress relief process is used to eliminate assembly stress generated during the assembly process.

6. The method according to any one of claims 1 to 4, characterized in that, The verification and confirmation of the assembled rotor, including the assembly accuracy and uniformity of the entire stage blades, includes: The rotor is subjected to low-speed turning test to verify the concentricity, flatness and gap uniformity of the entire stage blades.

7. An assembly stress control device for preventing breakage of sealing blades on a medium-pressure rotor, characterized in that, include: Pre-processing unit, matching unit, stress treatment unit, assembly unit, and verification unit; The pre-processing unit is used to clean and perform non-destructive testing on the sealing blades and blade root grooves of the rotor, and to measure the blade root thickness of the sealing blades and the groove size of the blade root grooves to establish a size database. The matching unit is used to match the sealing blade and the blade root groove based on the size database. The single-sided assembly gap between the sealing blade and the blade root groove belongs to a first gap range, which is 0.02mm to 0.05mm. The stress treatment unit is used to perform stress optimization treatment on the leaf root of the sealing blade. The assembly unit is used to assemble the sealing blade into the matching blade root groove using a non-impact loading method. The stress treatment unit is also used to eliminate the assembly stress generated during the assembly process after the sealing blade is assembled. The verification unit is used to verify the assembled rotor and confirm the assembly accuracy and uniformity of the entire stage blades.

8. The apparatus according to claim 7, characterized in that, The stress treatment unit is specifically used for at least one of the following: performing fine grinding and finishing on the root transition radius of the sealing blade, the steam inlet edge root and the steam outlet edge root of the sealing blade, and performing shot peening on the root surface of the sealing blade.

9. The apparatus according to claim 7, characterized in that, The non-impact loading method is a hydraulic progressive jacking assembly method.

10. The apparatus according to claim 7, characterized in that, The assembly unit is also used to monitor the assembly resistance in real time during the assembly process of the sealing blade.

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