A high-temperature super-rotation test device for an impeller

Abstract

This invention provides a high-temperature ultra-high-speed impeller testing device, comprising a long shaft, an impeller, a press-fit assembly, a buffer assembly, and a fixing component. The long shaft includes concentric first and second shaft bodies of different diameters. The impeller is fitted onto the first shaft body, with press-fit portions forming at both ends. The first and second press-fit assemblies are respectively press-fitted onto the press-fit portions on both sides of the impeller. Relative rotation is prevented by rectangular keys. The symmetrical layout of the double press-fit assemblies balances axial forces and improves rotational stability. Left / right clamps mate with left / right conical sleeves, and tension grooves are provided to accommodate impellers of different sizes and compensate for dimensional changes. The buffer assembly is mirror-symmetrically arranged, and its flared design optimizes stress distribution, absorbs thermal expansion of the long shaft, and resists vibration and impact. The fixing component provides axial fixing force and optimizes the axial stiffness of the system. This device ensures reliable impeller positioning under high temperature and ultra-high speed conditions, improving testing accuracy and reliability.

Description

Technical Field

[0001] This invention relates to the field of impeller technology, and in particular to a high-temperature over-rotation test device for impellers. Background Technology

[0002] As a critical hot-end component, the gas turbine impeller operates in a high-temperature, high-pressure gas environment, requiring it to withstand extremely high speeds and loads. Its designed operating speed range is 80,000 to 90,000 rpm, with operating temperatures reaching 700°C to 800°C. Under these extreme conditions, the impeller's material properties, structural strength, and thermal stability face severe challenges. To ensure the reliability and safety of the gas turbine during long-term operation, high-temperature overspeed performance tests must be conducted on the impeller to verify whether its performance indicators under design conditions meet the requirements.

[0003] However, existing impeller testing devices face numerous technical challenges in high-temperature overspeed testing.

[0004] First, because the impeller and the shaft are made of different materials, their thermal deformation is inconsistent due to the difference in their coefficients of thermal expansion under high temperature conditions. This can easily lead to impeller positioning failure or even damage to the equipment.

[0005] Secondly, traditional testing devices are prone to thermal stress concentration under the combined effects of high-speed rotation and high temperature, which can cause thermal deformation of the impeller or shaft and affect the accuracy of the test data.

[0006] In addition, existing devices have difficulty maintaining stable axial clamping force at high temperatures, which causes axial movement of the impeller during rotation, affecting the safety and reliability of the test.

[0007] More critically, existing technologies lack an effective thermal expansion compensation mechanism, making it impossible to automatically adapt to dimensional changes in the impeller and shaft at high temperatures. This results in difficulty maintaining precise coaxial positioning of the impeller under extreme operating conditions. This not only limits the testing capabilities of the experimental device but also increases the risks associated with gas turbine impellers in practical applications.

[0008] Therefore, developing a test device that can stably and reliably fix the impeller under high-temperature over-rotation conditions has become a key issue that urgently needs to be addressed in the current research and development of gas turbine technology. Summary of the Invention

[0009] Therefore, it is necessary to address the technical problems of existing high-temperature overspeed test devices for impellers, such as difficulty in ensuring stable impeller positioning under high temperature and ultra-high speed rotation conditions, susceptibility to positioning failure due to thermal expansion, and inability to accurately simulate the actual working environment of gas turbines. A new high-temperature overspeed test device should be provided to enable reliable impeller positioning under ultra-high temperature (above 700℃) and ultra-high speed (80,000-90,000 rpm) conditions, effectively compensate for axial deformation caused by thermal expansion, ensure long-term stable operation of the test device, and improve testing accuracy and reliability.

[0010] This invention provides a high-temperature overspeed test device for impellers, comprising a long shaft, an impeller, a press-fit assembly, a buffer assembly, and a fixing component. The long shaft includes a first shaft and a second shaft with concentric arrangement and different diameters, the diameter of the first shaft being smaller than the diameter of the second shaft. The impeller is sleeved on the first shaft of the long shaft, and the two ends of the inner ring of the impeller extend outward along the axial direction to form press-fit portions. The first press-fit assembly is sleeved on the first shaft between the impeller and the long shaft, and the first press-fit assembly is press-fitted onto one of the press-fit portions of the impeller. A plurality of rectangular keys distributed in a ring are inserted through the end face of the first press-fit assembly, and the two ends of the rectangular keys are respectively inserted into the second shaft of the long shaft and the side wall of the impeller. The second press-fit assembly is sleeved on the first shaft on the other side of the impeller, and the second press-fit assembly is press-fitted onto the other press-fit portion of the impeller. The device provides high-strength support through a double-diameter structure of the long shaft, and achieves torque transmission and axial positioning through the precise fit between the press-fit assembly and the impeller. The rectangular key design effectively prevents relative rotation between the impeller and the long shaft, ensuring synchronous rotation. At the same time, the symmetrical layout of the double press-fit assembly balances the axial force, reduces deformation and stress concentration caused by unilateral force, and improves the rotational stability and testing accuracy of the impeller.

[0011] In other embodiments, the first press-fit assembly includes a left clamp and a left tapered sleeve. The left clamp has a second support plate sleeved on the first shaft and a second annular guard circumferentially disposed on the second support plate. The second annular guard is press-fitted onto the press-fitting portion on the corresponding side of the impeller, and the second annular guard is infinitely close to the end face of the corresponding side of the impeller. The left tapered sleeve has a first support plate sleeved on the first shaft and a first annular guard circumferentially disposed on the first support plate. The first annular guard is sleeved on the second annular guard, and a first gap h1 is provided between the first annular guard and the end face of the impeller, satisfying: 1mm≤h1≤2mm. Keyholes corresponding to rectangular keys are provided on the end faces of both the first support plate and the second support plate. The design of the left collet and the left tapered sleeve achieves self-locking and elastic compensation through the tapered surface. The first gap h1 provides the necessary buffer space for high-temperature expansion and mechanical deformation, preventing the components from jamming or being damaged due to thermal stress. At the same time, the keyhole design ensures the accurate installation of the rectangular key, realizes the reliable transmission of torque, and prevents relative rotation between components. This precise mechanical connection method has higher positioning accuracy and reliability than the traditional key connection, effectively reduces vibration and noise, and improves the overall performance of the system.

[0012] In other embodiments, the inner wall of the first annular guard is tapered, and the radial thickness of the first annular guard on the side away from the first support plate is less than the radial thickness of the first annular guard on the side closer to the first support plate; the outer wall of the second annular guard has a tapered setting corresponding to the inner wall of the first annular guard. This corresponding tapered design ensures that a perfect tapered surface fit can be formed between the left tapered sleeve and the left clamping sleeve. When axial force is applied, the two can fit tightly together, achieving efficient torque transmission and precise axial positioning. At the same time, this design facilitates installation and disassembly, and the thickness design optimizes stress distribution, making the tension force more uniform, reducing the risk of deformation or damage caused by local stress concentration, and improving the service life and reliability of the component.

[0013] In other embodiments, the second annular guard edge has multiple annularly distributed first tension grooves circumferentially distributed on the side near the impeller. Under axial force, these grooves can generate slight elastic deformation, causing a change in the inner diameter of the second annular guard edge, thereby clamping or loosening the impeller press-fit part. This elastic tensioning mechanism can not only adapt to impellers of different sizes, but also compensate for dimensional changes caused by thermal expansion or mechanical wear, ensuring a long-term stable fixing effect. At the same time, the design of the tension grooves can also improve the elastic modulus of the component, enhance its resistance to vibration and impact, and improve the overall reliability of the system.

[0014] In other embodiments, the second press-fit assembly includes a right clamp and a right tapered sleeve. The right clamp has a third support plate fitted onto the first shaft and a third annular guard circumferentially arranged around the third support plate. The third annular guard is press-fitted onto the press-fit portion on the corresponding side of the impeller, and the third annular guard is infinitely close to the end face of the corresponding side of the impeller. The right tapered sleeve has a fourth support plate fitted onto the first shaft and a fourth annular guard circumferentially arranged around the fourth support plate. The fourth annular guard is fitted onto the third annular guard, and a second gap h2 is provided between the fourth annular guard and the end face of the impeller, satisfying: 1mm≤h2≤2mm. The design principle of the right clamp and the right tapered sleeve is the same as that of the left clamp and the left tapered sleeve. The tensioning function is achieved through tapered fit. The setting of the second gap h2 provides necessary buffer space for high-temperature expansion and mechanical deformation, preventing the assembly from jamming or being damaged due to thermal stress. At the same time, this gap fit can also achieve precise axial positioning during installation by adjusting the axial force, forming a symmetrical fixed structure with the left tapered sleeve, improving the overall stability of the system.

[0015] In other embodiments, the inner wall of the fourth annular guard is tapered, and the radial thickness of the fourth annular guard on the side away from the fourth support plate is less than the radial thickness of the fourth annular guard on the side closer to the fourth support plate; the outer wall of the third annular guard has a tapered setting corresponding to the inner wall of the fourth annular guard. This tapered design allows the right tapered sleeve to contract radially when subjected to axial force, thereby achieving a tightening effect on the right clamp, improving the impeller's fixing effect, and ensuring that a perfect tapered surface fit can be formed between the right tapered sleeve and the right clamp. When axial force is applied, the two can fit tightly together, achieving efficient torque transmission and precise axial positioning. At the same time, this design is also convenient for installation and disassembly, forming a symmetrical layout with the tapered surface fit structure on the left side, enhancing the system's balance and stability. The variable thickness design optimizes stress distribution, making the tightening force more uniform and reducing the risk of deformation or damage caused by local stress concentration.

[0016] In other embodiments, the third support plate and the third annular guard are provided with a plurality of annularly distributed second tension grooves on the side away from the impeller; the third annular guard is provided with a plurality of annularly distributed third tension grooves on the side close to the impeller; and the second tension grooves and the third tension grooves are staggered. The second tensioning groove is similar to the first tensioning groove, but its special layout on the right sleeve can adapt to different stress conditions. Under axial force, these grooves can produce slight elastic deformation, causing the inner diameter of the third annular guard to change, thereby clamping or loosening the impeller pressing part. The position and number of the third tensioning grooves can ensure a uniform tension force distribution under axial force, preventing impeller deformation or damage caused by local stress concentration. At the same time, this multi-groove design can also improve the elastic modulus of the component and enhance its resistance to vibration and impact. The staggered distribution of the second and third tensioning grooves compensates for each other through elastic deformation in different directions, reducing dimensional deviations caused by deformation in a single direction. This layout can also optimize stress distribution, making the tension force act more evenly on the impeller surface, improving the fixing effect and testing accuracy.

[0017] In other embodiments, an annular groove is formed on the outer wall of the section where the fourth annular guard connects to the fourth support plate. The functions of the annular groove include: firstly, it can reduce the weight of the component, reduce inertial forces, and improve the dynamic response characteristics of the system; secondly, the annular groove can serve as a stress relief zone, reducing stress concentration caused by thermal expansion or mechanical loads; finally, the annular groove can also serve as an installation positioning mark, facilitating precise assembly and debugging of the component. This multi-functional design reflects the ingenuity and practicality of the engineering design, improving the overall performance and reliability of the component.

[0018] In other embodiments, a fixing member and a buffer assembly are also included. The fixing member is threaded onto the first shaft body; the buffer assembly is disposed between the second press-fit assembly and the fixing member. The fixing member is typically a fastening nut, which is threaded onto the first shaft body and tightly engages with it via a threaded connection, providing reliable axial fixing force. The threaded connection can also optimize the axial stiffness of the system by adjusting the preload to meet the needs of different test conditions. The special position design of the buffer assembly enables it to fully exert its buffering and compensation functions. In high-temperature environments, the long shaft and impeller will have different amounts of thermal expansion due to different materials. The buffer assembly can absorb this difference, preventing component damage due to excessive compression or positioning failure due to insufficient compression, ensuring that the system maintains stable performance under various operating conditions.

[0019] In other embodiments, two buffer assemblies are arranged in a mirror-symmetrical configuration. Each buffer assembly has a fifth support plate and a fifth annular guard circumferentially arranged around the fifth support plate. The fifth annular guard flares outward from a flared shape, and the two fifth support plates are positioned opposite each other after the two buffer assemblies are installed. The special layout and flared design of the two buffer assemblies enable them to generate synergistic elastic deformation when subjected to axial force. The relative arrangement of the fifth support plates forms an elastic buffer cavity that can absorb and disperse axial force. At the same time, the flared design of the fifth annular guard optimizes stress distribution, making deformation more uniform. This design not only effectively compensates for the thermal expansion of the long shaft but also resists vibration and impact caused by impeller imbalance, improving the overall stability and reliability of the system. Its working principle is that at high temperatures, the long shaft elongates and pushes the buffer assembly, causing the flared structure to generate elastic deformation, absorbing part of the elongation. Simultaneously, through the interaction of the fifth support plates, the remaining axial force is evenly transmitted to the second press-fit assembly, ensuring that the impeller always maintains stable axial positioning. Attached Figure Description

[0020] Figure 1 This is a partial cross-sectional view of the present invention.

[0021] Figure 2 This is a schematic diagram of the long axis in this invention.

[0022] Figure 3 These are the front view and sectional view of the left conical sleeve in this invention.

[0023] Figure 4 This is a three-dimensional structural diagram of the left jacket in this invention.

[0024] Figure 5 This is the main view of the left sleeve in this invention.

[0025] Figure 6 This is a three-dimensional structural diagram of the right jacket in this invention.

[0026] Figure 7 This is a cross-sectional view of the right conical sleeve in this invention.

[0027] Figure 8 This is a cross-sectional view of the buffer component in this invention.

[0028] in:

[0029] 1. Long shaft; 101. First shaft body; 102. Second shaft body; 2. Left tapered sleeve; 201. First support plate; 202. First annular guard; 203. First shaft hole; 204. First keyhole; 3. Left clamping sleeve; 301. Second support plate; 302. Second annular guard; 303. Second shaft hole; 304. Second keyhole; 305. First tension groove; 4. Right clamping sleeve; 401. Third support plate; 402. Third annular guard ; 403, Third shaft hole; 404, Second tension groove; 405, Third tension groove; 5, Right cone sleeve; 501, Fourth support plate; 502, Fourth annular guard; 503, Fourth shaft hole; 504, Annular groove; 6, Buffer assembly; 601, Fifth support plate; 602, Fifth annular guard; 603, Fifth shaft hole; 7, Fixing component; 8, Rectangular key; 9, Impeller; 901, First pressing part; 902, Second pressing part of impeller. Detailed Implementation

[0030] The specific embodiments of the present invention will now be described with reference to the accompanying drawings.

[0031] like Figures 1-8 As shown in the figure, this embodiment discloses a high-temperature over-rotation test device for impellers, including a long shaft 1, an impeller 9, a press-fit assembly, a buffer assembly 6, and a fixing component 7. It enables the testing of the impeller 9 under ultra-high temperatures (above 700°C) and over-rotation (80,000 rpm to 90,000 rpm), overcoming the thermal expansion caused by ultra-high temperatures and over-rotation, thus ensuring stable and reliable rotation of the impeller 9. Through the coordinated operation of a precisely designed structure and components, the device ensures stable and reliable operation of the impeller 9 under extreme high-temperature and high-speed rotation conditions. This is crucial for simulating the performance testing of the impeller 9 under real-world working conditions, helping to identify potential problems early, optimize product design, and improve product reliability and service life.

[0032] like Figure 2 As shown, the long shaft 1 in this embodiment includes a first shaft 101 and a second shaft 102 that are concentrically arranged and have different diameters. The diameter of the first shaft 101 is smaller than the diameter of the second shaft 102. As the main support structure of the entire test device, the long shaft 1 has a specially designed double-diameter structure that not only provides sufficient strength and rigidity to withstand the huge centrifugal force generated by the high-speed rotation of the impeller 9, but also effectively disperses stress concentration, reduces the risk of fatigue fracture, and provides a precise positioning reference for the installation of other components.

[0033] like Figure 1As shown, in this embodiment, the impeller 9 is sleeved on the first shaft body 101 of the long shaft 1. The two ends of the inner ring of the impeller 9 extend outward along the axial direction to form a first press-fit part 901 and an impeller second press-fit part 902. The structural design of the impeller 9 not only increases the contact area with the long shaft 1 and improves the torque transmission efficiency, but also effectively disperses the axial pressure and reduces local stress concentration. Its first press-fit part 901 and impeller second press-fit part 902 provide a stable installation position for the press-fit assembly, ensuring the axial positioning accuracy of the impeller 9 when rotating at high speed.

[0034] like Figure 1 As shown, in this embodiment, the first press-fit assembly is sleeved on the first shaft 101 between the impeller 9 and the long shaft 1. The first press-fit assembly is pressed onto the first press-fit part 901 of the impeller 9, and a plurality of rectangular keys 8 distributed in a ring are inserted through the end face of the first press-fit assembly. The two ends of the rectangular keys 8 are respectively inserted into the second shaft 102 of the long shaft 1 and the side wall of the impeller 9. The first press-fit assembly achieves a reliable connection between the impeller 9 and the long shaft 1 through precise mechanical fit and fixation of the rectangular keys 8. The rectangular keys 8 not only transmit torque, but also prevent the impeller 9 from sliding circumferentially relative to the long shaft 1, ensuring that the two rotate synchronously. This design effectively improves the overall rigidity and dynamic response characteristics of the system.

[0035] like Figure 1 As shown, in this embodiment, the second press-fit assembly is sleeved on the first shaft 101 on the other side of the impeller 9, and the second press-fit assembly is press-fitted onto the impeller second press-fit part 902 of the impeller 9. The second press-fit assembly works in conjunction with the first press-fit assembly to axially position and fix the impeller 9 from both sides. This symmetrical design can effectively balance the axial force, reduce deformation and stress concentration caused by unilateral force, improve the rotational stability and testing accuracy of the impeller 9, and facilitate installation and debugging.

[0036] In this embodiment, the first press-fitting assembly includes a left clamping sleeve 3 and a left conical sleeve 2.

[0037] Specifically, such as Figures 4-5 As shown, in this embodiment, the left sleeve 3 has a second support plate 301 sleeved on the first shaft 101, and a second annular guard 302 circumferentially arranged around the second support plate 301. The second support plate 301 and the second annular guard 302 are integral structures. The second annular guard 302 is pressed onto the first pressing part 901 of the impeller 9, and the second annular guard 302 is infinitely close to the end face of the first pressing part 901 of the impeller 9. Through the precise fit between the second support plate 301 and the first shaft 101, and the pressing of the second annular guard 302 onto the first pressing part 901 of the impeller 9, the left sleeve 3 realizes axial positioning and partial torque transmission functions. Its design of being infinitely close to the end face of the impeller 9 can effectively reduce axial movement, improve positioning accuracy, and provide a basis for subsequent tension adjustment.

[0038] like Figure 3 As shown, in this embodiment, the left conical sleeve 2 has a first support plate 201 sleeved on the first shaft 101, and a first annular guard 202 circumferentially arranged on the first support plate 201. The first support plate 201 and the first annular guard 202 are an integral structure, which improves the overall strength.

[0039] The first annular guard 202 is fitted onto the second annular guard 302, and a first gap h1 is provided between the first annular guard 202 and the end face of the first press-fit part 901 of the impeller 9, satisfying: 1mm≤h1≤2mm. The left tapered sleeve 2 can form a precise tapered surface fit with the left clamping sleeve 3. The setting of the first gap h1 provides the necessary buffer space for high-temperature expansion and mechanical deformation, preventing the components from jamming or being damaged due to thermal stress. At the same time, this gap fit can also achieve precise axial positioning by adjusting the axial force during installation.

[0040] like Figure 3 and Figure 4 As shown, keyholes corresponding to the rectangular key 8 are provided on the end faces of both the first support plate 201 and the second support plate 301. The design of the keyholes ensures that the rectangular key 8 can be accurately installed, realizes reliable torque transmission, and prevents relative rotation between components. This precise mechanical connection method has higher positioning accuracy and reliability than traditional key connections, effectively reduces vibration and noise, and improves the overall performance of the system.

[0041] In this embodiment, the inner wall of the first annular guard 202 is tapered, and the radial thickness of the first annular guard 202 on the side away from the first support plate 201 is less than the radial thickness of the first annular guard 202 on the side closer to the first support plate 201; the outer wall of the second annular guard 302 has a tapered setting corresponding to the inner wall of the first annular guard 202. (This corresponding tapered design ensures that a perfect tapered surface fit can be formed between the left tapered sleeve 2 and the left clamping sleeve 3. When axial force is applied, the two can fit tightly together, achieving efficient torque transmission and precise axial positioning. At the same time, this design also facilitates installation and disassembly, and the thickness design optimizes stress distribution, making the tension force more uniform and reducing the risk of deformation or damage caused by local stress concentration.)

[0042] In this embodiment, the second annular guard 302 has multiple annularly distributed first tensioning grooves 305 on the circumferential side near the impeller 9. Under the action of axial force, these grooves can produce slight elastic deformation, causing the inner diameter of the second annular guard 302 to change, thereby clamping or loosening the first pressing part 901 of the impeller 9. This elastic tensioning mechanism can not only adapt to impellers 9 of different sizes, but also compensate for dimensional changes caused by thermal expansion or mechanical wear, ensuring a long-term stable fixing effect.

[0043] In this embodiment, the second press-fitting assembly includes a right clamping sleeve 4 and a right conical sleeve 5.

[0044] Specifically, such as Figure 6 As shown, the right sleeve 4 in this embodiment has a third support plate 401 sleeved on the first shaft 101 and a third annular guard 402 circumferentially arranged around the third support plate 401. The third support plate 401 and the third annular guard 402 are an integral structure.

[0045] The third annular guard 402 is press-fitted onto the second press-fit part 902 of the impeller 9, and the third annular guard 402 is infinitely close to the end face of the second press-fit part 902 of the impeller 9. The right sleeve 4 corresponds to the left sleeve 3. Through the cooperation of the third support plate 401 and the first shaft 101, and the press-fitting of the third annular guard 402 onto the second press-fit part 902 of the impeller 9, axial positioning and partial torque transmission functions are realized. Its design of being infinitely close to the end face of the impeller 9 can effectively reduce axial movement and improve positioning accuracy. Working together with the left sleeve 3, it ensures the stable rotation of the impeller 9.

[0046] like Figure 7 As shown, in this embodiment, the right conical sleeve 5 has a fourth support plate 501 sleeved on the first shaft 101, and a fourth annular guard 502 circumferentially arranged around the fourth support plate 501. The fourth support plate 501 and the fourth annular guard 502 are an integral structure.

[0047] The fourth annular guard 502 is fitted onto the third annular guard 402, and a second gap h2 is provided between the fourth annular guard 502 and the end face of the second press-fit part 902 of the impeller 9, satisfying: 1mm≤h2≤2mm. The design principle of the right tapered sleeve 5 is the same as that of the left tapered sleeve 2, achieving the tensioning function through tapered fit. The setting of the second gap h2 provides necessary buffer space for high-temperature expansion and mechanical deformation, preventing component jamming or damage caused by thermal stress. At the same time, this gap fit can also achieve precise axial positioning by adjusting the axial force during installation, forming a symmetrical fixed structure with the left tapered sleeve 2, improving the overall stability of the system.

[0048] In this embodiment, the inner wall of the fourth annular guard 502 is tapered, and the radial thickness of the fourth annular guard 502 on the side away from the fourth support plate 501 is less than the radial thickness of the fourth annular guard 502 on the side close to the fourth support plate 501. Its variable thickness design optimizes the stress distribution, makes the tension force more uniform, and reduces the risk of deformation or damage caused by local stress concentration. It echoes the design of the left cone sleeve 2 to form a complete fixing system.

[0049] The outer wall of the third annular guard 402 has a taper setting corresponding to the inner wall of the fourth annular guard 502. This taper design allows the right cone sleeve 5 to undergo radial contraction when subjected to axial force, thereby achieving a tightening effect on the right clamping sleeve 4, improving the fixing effect of the impeller 9, and ensuring that a perfect conical surface fit can be formed between the right cone sleeve 5 and the right clamping sleeve 4. When axial force is applied, the two can fit tightly together, achieving efficient torque transmission and precise axial positioning. At the same time, this design also facilitates installation and disassembly, improves maintenance efficiency, and forms a symmetrical layout with the conical surface fit structure on the left, enhancing the balance and stability of the system.

[0050] In this embodiment, as Figure 6 As shown, the third support plate 401 and the third annular guard 402 have multiple annularly distributed second tension grooves 404 on the side away from the impeller 9. The second tension grooves 404 are similar to the first tension grooves 305, but the special layout on the right sleeve 4 can adapt to different stress conditions. Under the action of axial force, these grooves can produce slight elastic deformation, causing the inner diameter of the third annular guard 402 to change, thereby achieving the clamping or loosening of the impeller 9 impeller second press-fit part 902. This elastic tensioning mechanism can not only adapt to impellers 9 of different sizes, but also compensate for dimensional changes caused by thermal expansion or mechanical wear, ensuring a long-term stable fixing effect.

[0051] The third annular guard 402 has multiple annularly distributed third tension grooves 405 on the side near the impeller 9. The position and number of the third tension grooves 405 can ensure that a uniform tension force distribution is generated under the action of axial force, preventing the impeller 9 from being deformed or damaged due to local stress concentration. At the same time, this multi-groove design can also improve the elastic modulus of the component, enhance its resistance to vibration and impact, and improve the overall reliability of the system.

[0052] In this embodiment, the second tensioning groove 404 and the third tensioning groove 405 are staggered. Through mutual compensation of elastic deformation in different directions, dimensional deviations caused by deformation in a single direction are reduced. Simultaneously, this layout optimizes stress distribution, allowing the tensioning force to act more evenly on the impeller 9 surface, improving the fixing effect and testing accuracy.

[0053] In this embodiment, an annular groove 504 is formed on the outer wall of the section where the fourth annular guard 502 connects to the fourth support plate 501. The functions of the annular groove 504 include: firstly, it can reduce the weight of the component, reduce inertial force, and improve the dynamic response characteristics of the system; secondly, the annular groove 504 can serve as a stress relief zone, reducing stress concentration caused by thermal expansion or mechanical load; finally, the annular groove 504 can also serve as an installation positioning mark, facilitating the precise assembly and debugging of the component. This multifunctional design reflects the ingenuity and practicality of the engineering design.

[0054] This embodiment also includes a fastener 7 and a buffer assembly 6.

[0055] The fastener 7 is usually a fastening nut, which is threaded onto the first shaft 101. It is tightly fitted to the first shaft 101 through a threaded connection, providing a reliable axial fixing force. The threaded connection can also optimize the axial stiffness of the system by adjusting the preload, so as to meet the requirements under different test conditions.

[0056] like Figure 8 As shown, the buffer assembly 6 is positioned between the second press-fit assembly and the fixing member 7. The special positioning design of the buffer assembly 6 enables it to fully exert its buffering and compensation functions. In high-temperature environments, the long shaft 1 and the impeller 9 will have different amounts of thermal expansion due to their different materials. The buffer assembly 6 can absorb this difference, preventing component damage due to excessive compression or positioning failure due to insufficient compression, and ensuring that the system maintains stable performance under various operating conditions.

[0057] In this embodiment, there are two buffer components 6 arranged in a mirror-symmetrical manner. Each buffer component 6 has a fifth support plate 601 and a fifth annular guard 602 arranged around the fifth support plate 601. The fifth support plate 601 and the fifth annular guard 602 are integral structures, and the fifth annular guard 602 expands outward with a flared shape. After the two buffer components 6 are installed, the two fifth support plates 601 are arranged opposite to each other. The special layout and flared design of the two buffer components 6 enable them to generate synergistic elastic deformation when subjected to axial force. The relative arrangement of the fifth support plate 601 forms an elastic buffer cavity that can absorb and disperse axial force. At the same time, the flared design of the fifth annular guard 602 optimizes stress distribution and makes deformation more uniform. This design can not only effectively compensate for the thermal expansion of the long shaft 1, but also resist the vibration and impact caused by the unbalanced mass of the impeller 9, thereby improving the overall stability and reliability of the system. Its working principle is that at high temperature, the long shaft 1 elongates and pushes the buffer component 6. The flared structure generates elastic deformation to absorb part of the elongation. At the same time, through the interaction of the fifth support plate 601, the remaining axial force is evenly transmitted to the second press-fit component, ensuring that the impeller 9 always maintains a stable axial position.

[0058] The technical solution adopted in this invention is to fix the impeller 9 on the long shaft 1 and connect the long shaft 1 to the testing machine to simulate the working environment of the impeller 9 in a gas turbine and conduct tests on the impeller 9. This method can realistically reproduce the stress state and thermal environment of the impeller 9 in actual operation. By precisely controlling parameters such as temperature, speed, and load, the performance indicators of the impeller 9, such as strength, fatigue life, and thermal stability, can be comprehensively evaluated, providing reliable data support for product optimization design. Furthermore, this testing method can identify potential design defects or manufacturing problems in advance, avoiding malfunctions during actual use and greatly improving the reliability and safety of the product.

[0059] Specifically, the installation process in this embodiment is as follows:

[0060] The left tapered sleeve 2 is interference-fitted onto the long shaft 1 and close to the large end face of the long shaft 1. Two rectangular keys 8 are fixed on the long shaft 1 and pass through the left tapered sleeve 2, restricting the circumferential rotation of the left tapered sleeve 2. The right end of the rectangular key 8 is engaged in the keyway at the left end of the impeller 9, driving the impeller 9 to rotate and transmitting torque. This precise mechanical connection ensures efficient torque transmission. The interference fit design of the left tapered sleeve 2 provides sufficient friction to prevent loosening, while the rectangular key 8 achieves circumferential positioning through precise keyway engagement, preventing relative rotation. This dual positioning mechanism greatly improves the reliability and safety of the system. At the same time, this design also facilitates installation and disassembly, improving maintenance efficiency. In high-temperature environments, the interference fit and key connection can maintain stable performance, preventing connection failure due to thermal expansion.

[0061] The left jacket 3 has a tension groove on its circumference. The tension groove is designed to be through-hole, and its inner diameter changes under axial force, which can clamp or loosen the cylindrical surface of the left end of the impeller 9. The through-hole design of the tension groove allows the left jacket 3 to produce uniform elastic deformation when subjected to axial force. By precisely controlling the magnitude of the axial force, the left end of the impeller 9 can be precisely clamped or loosened. This elastic tensioning mechanism can not only adapt to impellers 9 of different sizes, but also compensate for dimensional changes caused by thermal expansion or mechanical wear, ensuring a long-term stable fixing effect. At the same time, the design of the tension groove can also improve the elastic modulus of the component, enhance its resistance to vibration and impact, and improve the overall reliability of the system.

[0062] The right sleeve 4 has 8 tension grooves along the circumference in different directions. When the fixing part 7 is tightened, the fixing part 7 pushes the two reverse-mounted (two fifth support plates 601 are set opposite each other, and the fifth annular guard 602 with a flared mouth expands outward) buffer components 6 and right cone sleeve 5 to move to the left. The diameter of the large hole of the right sleeve 4 that mates with the cone surface of the right cone sleeve 5 decreases, clamping the cylindrical surface of the right end of the impeller 9. The diameter of the small hole decreases, clamping the cylindrical surface of the long shaft 1, thus completing the positioning of the impeller 9 and making the impeller 9 coaxial with the long shaft 1. The tightening action of the fastener 7 triggers a series of precise mechanical movements: First, the axial force of the fastener 7 pushes the buffer assembly 6. The special design of the buffer assembly 6 causes it to undergo elastic deformation, absorbing part of the axial force and transmitting it evenly to the right tapered sleeve 5. The tapered surface design of the right tapered sleeve 5 converts the axial force into a radial force, causing the right clamp 4 to contract radially. Its large hole clamps the right end cylindrical surface of the impeller 9, and its small hole clamps the cylindrical surface of the long shaft 1. This double clamping mechanism ensures the precise coaxial positioning of the impeller 9 and the long shaft 1. At the same time, the special layout of the 8 tension grooves optimizes the stress distribution, making the tension force more uniform and reducing the risk of deformation or damage caused by local stress concentration. This intelligent tensioning system can automatically adapt to dimensional changes under different working conditions, ensuring a long-term stable fixing effect.

[0063] Because the impeller 9 and the long shaft 1 are made of different materials, if the thermal deformation and elongation of the long shaft 1 is too large under high temperature environment, the impeller 9 will fail to be positioned, which will cause danger or even damage the equipment. The specially designed buffer component 6 is used to compensate for the elongation of the long shaft 1 under high temperature to ensure that the axial clamping force meets the positioning requirements of the impeller 9.

[0064] In high-temperature environments, the long shaft 1 and impeller 9 will have different amounts of thermal expansion due to their different materials. Without a buffering mechanism, this difference will lead to excessive or insufficient axial clamping force. Excessive force may damage the components, while insufficient force may cause positioning failure. The buffer component 6 can absorb part of the elongation of the long shaft 1 through its elastic deformation capability, while uniformly transferring the remaining axial force to the second pressing component, ensuring that the impeller 9 always maintains a stable axial positioning. Its mirror symmetry design and flared structure further optimize the stress distribution, improve the buffering effect and system stability. This intelligent buffering mechanism greatly improves the adaptability and reliability of the device, enabling it to operate stably for a long time under extreme conditions.

[0065] After the impeller 9 is installed, the left end of the long shaft 1 is connected to the testing machine, and the high temperature over-rotation test can be carried out.

[0066] This invention employs a gapless positioning structure, ensuring reliable positioning of the impeller 9 on the rotating shaft. A specially designed buffer assembly 6 guarantees that the axial force meets the positioning requirements of the impeller 9 under high-temperature conditions. The gapless positioning structure, through precise mechanical design and manufacturing processes, ensures a zero-clearance fit between the impeller 9 and the long shaft 1. This design eliminates vibration and noise caused by clearances in traditional structures, improving the system's dynamic response characteristics and testing accuracy. Simultaneously, the gapless design prevents fretting wear caused by clearances, extending the component's service life. The special design of the buffer assembly 6 is a key innovation in solving the problem of thermal expansion under high-temperature conditions. Its elastic deformation capacity automatically compensates for the thermal expansion of the long shaft 1, ensuring that the axial clamping force remains within the optimal range. This intelligent buffering mechanism greatly improves the adaptability and reliability of the device, enabling long-term stable operation under extreme conditions. Practical use has verified that this invention indeed meets the design requirements. Under high-temperature and high-load testing conditions, it effectively solves problems such as thermal expansion, thermal deformation, thermal stress, and thermal centering caused by different materials of the impeller 9 and the rotating shaft, greatly improving the reliability and safety of the test.

[0067] The above description is an explanation of the present invention and not a limitation thereof. The scope of the present invention is defined by the claims. Within the scope of protection of the present invention, any form of modification may be made.

Claims

1. A high-temperature overspeed test device for impellers, characterized in that, include: The long shaft includes a first shaft and a second shaft that are concentrically arranged and have different diameters, wherein the diameter of the first shaft is smaller than the diameter of the second shaft. An impeller is fitted onto a first shaft body with a long shaft, and the two ends of the inner ring of the impeller extend outward along the axial direction to form a press-fit part; The first pressing assembly is sleeved on the first shaft body between the impeller and the long shaft. The first pressing assembly is pressed onto one of the pressing parts of the impeller, and a plurality of rectangular keys distributed in a ring are inserted through the end face of the first pressing assembly. The two ends of the rectangular keys are respectively inserted into the second shaft body of the long shaft and the side wall of the impeller. The second press-fitting assembly is sleeved on the first shaft body on the other side of the impeller, and the second press-fitting assembly is press-fitted onto another press-fitting part of the impeller; A buffer assembly is disposed between the second press-fit assembly and the fixing member; The first press-fit assembly includes: a left sleeve having a second support plate sleeved on the first shaft and a second annular guard circumferentially disposed on the second support plate, the second annular guard being press-fitted onto a press-fit portion on the corresponding side of the impeller, and the second annular guard being infinitely close to the end face of the corresponding side of the impeller; and a left tapered sleeve having a first support plate sleeved on the first shaft and a first annular guard circumferentially disposed on the first support plate, the first annular guard being sleeved on the second annular guard. The inner wall of the first annular guard is tapered, and the radial thickness of the first annular guard on the side away from the first support plate is less than the radial thickness of the first annular guard on the side closer to the first support plate; the outer wall of the second annular guard is tapered, corresponding to the inner wall of the first annular guard. The second press-fit assembly includes: a right sleeve having a third support plate sleeved on the first shaft and a third annular guard circumferentially disposed on the third support plate, the third annular guard being press-fitted on the press-fitting part on the corresponding side of the impeller, and the third annular guard being infinitely close to the end face of the corresponding side of the impeller. And, a right tapered sleeve having a fourth support plate sleeved on the first shaft and a fourth annular guard circumferentially disposed on the fourth support plate, the fourth annular guard sleeved on the third annular guard. The inner wall of the fourth annular guard is tapered, and the radial thickness of the fourth annular guard away from the fourth support plate is less than the radial thickness of the fourth annular guard close to the fourth support plate. The outer wall of the third annular guard has a tapered setting corresponding to the inner wall of the fourth annular guard.

2. The impeller high-temperature overspeed test device as described in claim 1, characterized in that: A first gap h1 is provided between the first annular guard edge and the impeller end face, and satisfies: 1mm≤first gap h1≤2mm; keyholes corresponding to the rectangular key are opened on the end faces of the first support plate and the second support plate.

3. The impeller high-temperature overspeed test device as described in claim 1, characterized in that: The second annular guard has multiple annularly distributed first tension grooves on the side near the impeller.

4. The impeller high-temperature overspeed test device as described in claim 1, characterized in that: The fourth annular guard is provided with a second gap h2 from the impeller end face, and satisfies: 1mm≤second gap h2≤2mm.

5. The impeller high-temperature overspeed test device as described in claim 1, characterized in that: The third support plate and the third annular guard are provided with multiple annularly distributed second tension grooves on the side away from the impeller. The third annular guard has multiple annularly distributed third tension grooves on the side near the impeller. Furthermore, the second tensioning groove and the third tensioning groove are staggered.

6. The impeller high-temperature overspeed test device as described in claim 4, characterized in that: A ring groove is provided on the outer wall of the section where the fourth annular guard edge connects to the fourth support plate.

7. The impeller high-temperature overspeed test device as described in claim 1, characterized in that: Also includes: The fastener is threaded onto the first shaft.

8. The impeller high-temperature overspeed test device as described in claim 7, characterized in that: The buffer assembly consists of two components arranged in a mirror-symmetrical manner. Each buffer assembly has a fifth support plate and a fifth annular guard surrounding the fifth support plate. The fifth annular guard expands outward in a funnel shape, and the two fifth support plates are positioned opposite each other after the two buffer assemblies are installed.

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