Flexible rotor cushioning energy-absorbing protection device

Abstract

This invention provides a flexible rotor buffer energy absorption protection device, relating to the field of flexible rotor technology, and solves the problem that when the bending critical speed of a flexible rotor is high, a violent collision may occur, leading to machine damage. The flexible rotor buffer energy absorption protection device includes: an annular base fitted over the flexible rotor and disposed on the inner wall of the flexible rotor's outer shell; and multiple buffer energy absorption elements mounted on the base; the base and the multiple buffer energy absorption elements correspond to the position where the flexible rotor has the greatest deflection when passing through the critical speed region. The solution of this invention can provide a collision buffer effect for the flexible rotor, absorb the vibration energy of the flexible rotor, and ensure that the flexible rotor safely passes through the bending critical speed.

Description

Technical Field

[0001] This invention relates to the field of flexible rotor technology, and in particular to a flexible rotor buffer energy absorption protection device. Background Technology

[0002] Flexible rotors are commonly found in large steam turbine units, compressors, magnetic levitation rotating machinery and other fields. During the acceleration process, the flexible rotor must pass through the critical speed of its own bending mode. The collision behavior in the critical state may cause damage to both the outer shell and the rotor. Especially when the bending critical speed of the flexible rotor is high, a violent collision may occur, resulting in machine damage.

[0003] The buffer energy absorption protection device utilizes the rotational inertia of the flexible rotor to control its severe vibration at the critical speed by applying a buffering effect, thus assisting the rotor in safely and smoothly passing the critical speed. The critical speed is a crucial speed range during the process of rotating machinery increasing to its operating speed, especially the bending mode critical speed of the flexible rotor itself, where the amplitude of the flexible rotor system increases rapidly and significantly in a short period. Currently, the most widely used over-critical technology in the field of rotating machinery is dynamic balancing. When performing dynamic balancing on a flexible rotor, the support end of the flexible rotor and the position with the greatest deflection at the critical speed need to be used as correction surfaces. Dynamic balancing of the system is achieved by adding (removing) weight. Since a flexible rotor consists of at least two rotor sections, the entire flexible rotor system has three correction surfaces. Performing dynamic balancing requires at least four acceleration and deceleration tests, making the process quite complex. Moreover, after the flexible rotor passes the critical speed, the correction mass, as part of the flexible rotor system, increases with its speed to the operating speed, becoming a detrimental factor at the operating speed. Summary of the Invention

[0004] This invention provides a flexible rotor buffer energy absorption protection device to solve the problem that when the bending critical speed of the flexible rotor is high, a violent collision may occur, resulting in machine damage.

[0005] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows:

[0006] A flexible rotor buffer energy absorption protection device, comprising:

[0007] An annular base is fitted over the flexible rotor and placed on the inner wall of the flexible rotor's outer shell.

[0008] Multiple buffer energy-absorbing elements are mounted on the base; the base and the multiple buffer energy-absorbing elements correspond to the position where the flexible rotor has the greatest deflection when passing through the critical speed region.

[0009] Optionally, multiple energy-absorbing buffer elements are evenly distributed on the annular base.

[0010] Optionally, each buffer energy-absorbing element includes: a metal-rubber spring fixed to the base and an amorphous thin-film DLC coated contact that cooperates with the metal-rubber spring.

[0011] Optionally, the metal rubber spring is a hollow cylinder, which is inserted into the pin of the base with a clearance fit.

[0012] Optionally, the base is also provided with a cylindrical spring, one end of which is connected to an amorphous thin film DLC coating contact, and the other end is connected to the inner wall of the flexible rotor's housing.

[0013] Optionally, there is a gap between the amorphous thin-film DLC coated contact and the flexible rotor.

[0014] Optionally, the amorphous thin-film DLC coated contact is a metal arc-shaped sheet with an amorphous thin-film DLC coating on its surface, and the radius of curvature of the DLC coated contact is a preset multiple of the radius of the outer wall of the metal rubber spring.

[0015] Optionally, the buffer energy-absorbing elements are at least 8 sets.

[0016] Optionally, the annular cross-section of the base is L-shaped.

[0017] Optionally, the axis of the base coincides with the axis of the flexible rotor.

[0018] The above-described solution of the present invention has at least the following beneficial effects:

[0019] The flexible rotor buffer energy absorption protection device of the present invention includes: an annular base sleeved over the flexible rotor and disposed on the inner wall of the flexible rotor's outer shell; a plurality of buffer energy absorption elements mounted on the base; the base and the plurality of buffer energy absorption elements corresponding to the position where the flexible rotor has the greatest deflection when passing through the critical speed region. The technical solution of the present invention provides a collision buffer effect for the flexible rotor, absorbs the vibration energy of the flexible rotor, and ensures that the flexible rotor safely passes through the bending critical speed. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the installation position of the flexible rotor buffer energy absorption protection device according to an embodiment of the present invention;

[0021] Figure 2 This is a schematic diagram of the structure of the flexible rotor buffer energy absorption protection device according to an embodiment of the present invention;

[0022] Figure 3 This is a partially enlarged schematic diagram of the flexible rotor buffer energy absorption protection device according to an embodiment of the present invention;

[0023] Figure 4This is a schematic diagram of the buffer energy absorption element structure of the flexible rotor buffer energy absorption protection device according to an embodiment of the present invention;

[0024] The components include: 1. Metal rubber spring; 2. DLC coated contact; 3. Spring; 4. Base; 5. Flexible rotor; and 6. Housing. Detailed Implementation

[0025] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this invention will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0026] like Figure 1 As shown, an embodiment of the present invention provides a flexible rotor buffer energy absorption protection device, comprising: an annular base 4 which is sleeved on the outside of the flexible rotor 5 and disposed on the inner wall of the outer shell 6 of the flexible rotor 5.

[0027] Multiple buffer energy-absorbing elements are installed on the base 4; the base 4 and the multiple buffer energy-absorbing elements correspond to the position where the flexible rotor 5 has the greatest deflection when it passes through the critical speed region.

[0028] The circular cross-section of the base 4 is L-shaped.

[0029] In this embodiment, the annular base 4 is sleeved on the outside of the flexible rotor 5 and is disposed on the inner wall of the outer shell 6 of the flexible rotor 5. The base 4 is provided with multiple buffer energy-absorbing elements, and the base 4 and the multiple buffer energy-absorbing elements correspond to the position where the flexible rotor 5 has the greatest deflection when passing through the critical speed region. The buffer energy-absorbing elements that rub against the rotor may experience problems such as film peeling, contact deformation, and spring failure. The single-sided open structure of the L-shaped ring provides space for external operation, and the buffer energy-absorbing elements can be repaired without disassembling the annular base 4.

[0030] This invention proposes a flexible rotor buffer energy absorption protection device, which is installed on a stationary outer shell 6. The buffer position is the point where the rotor deflection is at its maximum at the critical speed, so that the protection device has a better limiting effect and can solve the problem of collision damage to the flexible rotor 5 due to excessively high critical vibration. Using this device can avoid carrying out relatively complex dynamic balancing operations and can improve the safety and working efficiency of large rotating machinery.

[0031] like Figure 2 and Figure 3 As shown, an embodiment of the present invention proposes a flexible rotor buffer energy absorption protection device, wherein the plurality of buffer energy absorption elements are in 8 groups, and the 8 groups of buffer energy absorption elements are evenly distributed on the annular base 4.

[0032] Each buffer energy-absorbing element includes: a metal rubber spring 1 fixed on the base 4 and an amorphous thin film DLC coated contact 2 that cooperates with the metal rubber spring 1;

[0033] The metal rubber spring 1 is a hollow cylinder, which is inserted into the pin of the base 4 with a clearance fit.

[0034] The base 4 is also provided with a cylindrical spring 3. One end of the cylindrical spring 3 is connected to the amorphous thin film DLC coating contact 2, and the other end is connected to the inner wall of the outer shell 6 of the flexible rotor 5.

[0035] In this embodiment, the plurality of buffer energy-absorbing elements consist of 8 sets of metal rubber springs 1 and amorphous thin-film DLC coated contacts 2, which are mounted on the base 4 via pins and cylindrical springs 3. The 8 sets of buffer energy-absorbing elements are evenly distributed at 45° intervals. When the ratio of the radius of curvature of the amorphous thin-film DLC coated contact 2 to the radius of the outer surface of the flexible rotor 5 is in the range of 0.4 to 0.6, it can be ensured that the number of buffer energy-absorbing elements in contact with the flexible rotor 5 at the same time does not exceed 2. This allows the flexible rotor 5 to engage with the buffer energy-absorbing protection device in a discontinuous rubbing action when its amplitude exceeds the static gap, which helps the flexible rotor 5 to quickly get out of the rubbing state and restore stable operation. The metal rubber spring 1 is a hollow cylinder, which is inserted into the pin of the base 4 in a clearance fit manner, and its height is the same as that of the base 4. The metal rubber spring 1 is subjected to external force. When in use, the entire component undergoes compression deformation, and the internal elastic metal wires rub against each other while deforming, thus exhibiting damping energy dissipation characteristics. This absorbs part of the vibration capacity of the flexible rotor 5, assisting the rotor in escaping the resonant motion state. The clearance fit prevents the elastic metal wires near the center hole of the metal rubber spring 1 from being firmly fixed to the pin of the base 4 while deforming and rubbing. The amorphous thin film DLC coated contact 2 is a metal arc-shaped thin sheet with an amorphous thin film DLC coating on its surface. The surface friction coefficient is extremely low (0.02~0.05), ensuring that the friction force experienced by the flexible rotor 5 when it rubs against it is small. The metal material can be steel. The columnar spring 3 is in a stretched state in its original state and is mainly used to constrain the buffer energy absorption element composed of the metal rubber spring 1 and the amorphous thin film DLC coated contact 2.

[0036] like Figure 2 and Figure 4 As shown, in an optional embodiment of the present invention, there is a gap between the amorphous thin-film DLC coated contact 2 and the flexible rotor 5;

[0037] The radius of curvature of the DLC-coated contact 2 is 1.2 times the radius of the outer wall of the metal rubber spring 1;

[0038] The axis of the base 4 coincides with the axis of the flexible rotor 5.

[0039] In this embodiment, the axis of the base 4 coincides with the axis of the flexible rotor, ensuring an initial gap between the surface of the amorphous thin-film DLC coated contact 2 and the surface of the flexible rotor 5 in the radial position. When the rotational speed of the flexible rotor 5 approaches the critical speed, its amplitude increases rapidly. When the amplitude exceeds the initial gap, the flexible rotor 5 rubs against the amorphous thin-film DLC coated contact 2. The metal rubber spring 1 deforms under the pressure of the amorphous thin-film DLC coated contact 2. By designing the stiffness and damping performance of the metal rubber spring 1, it can provide a collision buffer effect for the flexible rotor 5 and absorb the vibration energy of the flexible rotor 5, ensuring that the flexible rotor 5 safely passes the critical speed. The radius of curvature of the amorphous thin-film DLC coated contact 2 is 1.2 times the radius of the outer wall of the metal rubber spring 1, which can prevent damage to the outer surface of the amorphous thin-film DLC coated contact 2 when the metal rubber spring 1 is deformed by pressure.

[0040] The flexible rotor buffer energy absorption protection device described in the above embodiments enables the flexible rotor 5 to rub against the protection device when its amplitude exceeds the initial gap with the protection device at the critical speed. The buffering function of the protection device can reduce the amplitude of the flexible rotor 5. At the same time, the protection device has a mating surface with an extremely low coefficient of friction and appropriate stiffness and damping properties, which can absorb the vibration energy of the flexible rotor 5 and ensure that the flexible rotor 5 system safely passes the critical speed.

[0041] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A flexible rotor buffer energy absorption protection device, comprising: An annular base (4) is fitted over the outside of the flexible rotor (5) and placed on the inner wall of the outer shell (6) of the flexible rotor (5). Multiple buffer energy-absorbing elements are installed on the base (4); the base (4) and the multiple buffer energy-absorbing elements correspond to the position where the flexible rotor (5) has the greatest deflection when it passes through the critical speed region; Each buffer energy-absorbing element includes: a metal rubber spring (1) fixed on the base (4) and an amorphous thin film DLC coated contact (2) that cooperates with the metal rubber spring (1). The metal rubber spring (1) is a hollow cylinder, which is inserted into the pin of the base (4) in a clearance fit manner; The amorphous thin film DLC coated contact (2) is a metal arc-shaped sheet with an amorphous thin film DLC coating on its surface. The radius of curvature of the DLC coated contact (2) is 1.2 times the radius of the outer wall of the metal rubber spring (1).

2. The flexible rotor energy absorbing cushioning protector of claim 1 wherein, Multiple buffer energy-absorbing elements are evenly distributed on the annular base (4).

3. The flexible rotor buffer energy absorption protection device as described in claim 1, characterized in that, The base (4) is also provided with a cylindrical spring (3), one end of which is connected to the amorphous thin film DLC coating contact (2), and the other end is connected to the inner wall of the outer shell (6) of the flexible rotor (5).

4. The flexible rotor buffer energy absorption protection device as described in claim 1, characterized in that, There is a gap between the amorphous thin film DLC coated contact (2) and the flexible rotor (5).

5. The flexible rotor buffer energy absorption protection device as described in claim 1, characterized in that, The buffer energy-absorbing elements consist of at least 8 sets.

6. The flexible rotor buffer energy absorption protection device as described in claim 1, characterized in that, The annular cross-section of the base (4) is L-shaped.

7. The flexible rotor buffer energy absorption protection device as described in claim 1, characterized in that, The axis of the base (4) coincides with the axis of the flexible rotor (5).

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