Vibration control method for foundation platform of vertical ring magnetic separator

Abstract

The invention relates to a vibration control method for a foundation platform of a vertical ring magnetic separator, which is characterized by comprising the following steps: S1, acquiring vertical vibration parameters and vibration response of the foundation platform of the vertical ring magnetic separator; s2, the vertical vibration frequency of the vertical ring magnetic separator foundation platform is checked, the vibration response of the vertical ring magnetic separator foundation platform is checked, and if the vertical vibration frequency in the step S2 does not meet the frequency control condition, a vibration control measure A is determined according to the checking result; or, if the vibration response in the step S3 does not meet the response control condition, determining a vibration control measure B according to the checking result; s5, verifying the effectiveness of the vibration control measures; and S6, when the control condition of frequency + response is met, the vibration control process is ended. According to the invention, a vibration control strategy of first frequency and then response is adopted, which is not only comprehensive, but also effective and efficient; finite element software is used for verifying the effectiveness of vibration control measures, repeated vibration treatment can be avoided, and the vibration treatment cost is reduced.

Description

Technical Field

[0001] This invention belongs to the field of industrial engineering vibration control technology, specifically relating to a vibration control method for a vertical ring magnetic separator foundation platform. Background Technology

[0002] Vertical ring magnetic separators are important large-scale equipment in ferrous metallurgical beneficiation operations. According to the needs of the beneficiation process, vertical ring magnetic separators are generally arranged on a foundation platform. Since vertical ring magnetic separators are low-frequency equipment, they are prone to resonance with the foundation platform. Moreover, as the equipment capacity increases, the disturbance force also increases sharply, and the abnormal vibration problem of the foundation platform caused by this becomes more and more prominent.

[0003] Abnormal vibration of the base platform not only affects the normal operation of the vertical ring magnetic separator, but also the platform structure and personnel safety, making it a problem that mineral processing production must solve. Currently, there is a lack of effective solutions to this problem, and solutions generally rely on experience, resulting in the following adverse consequences: first, the platform structure is overly conservative, leading to waste; second, the abnormal vibration problem is not completely resolved, potentially requiring multiple vibration control measures, which are not only time-consuming and costly, but also affect production. Summary of the Invention

[0004] The purpose of this invention is to provide a vibration control method for a vertical ring magnetic separator foundation platform, which can effectively solve the vibration problem of the vertical ring magnetic separator foundation platform.

[0005] To achieve the above objectives, embodiments of the present invention provide a vibration control method for a vertical ring magnetic separator foundation platform, characterized by comprising the following steps:

[0006] S1. Obtain the vertical vibration parameters and vibration response of the vertical ring magnetic separator foundation platform;

[0007] S2. Check the vertical vibration frequency of the vertical ring magnetic separator base platform. If the vertical vibration frequency meets the frequency control conditions, proceed to step S3; otherwise, proceed to step S4.

[0008] S3. Check the vibration response of the vertical ring magnetic separator foundation platform. If the vibration response meets the response control conditions, proceed to step S6; otherwise, proceed to step S4.

[0009] S4. If the vertical vibration frequency in step S2 does not meet the frequency control conditions, determine vibration control measure A based on the verification results; or, if the vibration response in step S3 does not meet the response control conditions, determine vibration control measure B based on the verification results.

[0010] S5. Verify the effectiveness of the vibration control measures;

[0011] S6. Once the "frequency + response" control conditions are met, the vibration control process ends.

[0012] Preferably, the acquisition of vertical vibration parameters and vibration response of the vertical ring magnetic separator foundation platform in step S1 includes two methods: finite element analysis (FEM) or on-site testing. FEM is used for vibration control in new projects or to verify the effectiveness of vibration control measures, while on-site testing is used for vibration mitigation of existing vertical ring magnetic separator foundation platforms. FEM uses general-purpose finite element software such as ANSYS, ABAQUS, or SAP2000; on-site testing uses a multi-channel data acquisition instrument, vibration sensors, and the accompanying "DASP - Intelligent Data Acquisition and Signal Processing System" software.

[0013] Preferably, the vertical vibration parameters of the vertical ring magnetic separator foundation platform in step S1 include the mode shape, frequency, and mode mass participation coefficient of the vertical vibration, and the vibration response includes vibration acceleration, vibration velocity, and vibration displacement.

[0014] Preferably, the vertical vibration frequency of the foundation platform of the vertical ring magnetic separator in step S2 should satisfy the following expression:

[0015] ;

[0016] In the formula, f c f represents the control frequency. e The vibration frequency of the vertical ring magnetic separator is represented by [f] (provided by the vertical ring magnetic separator manufacturer; if it is variable, take the maximum value). [f] represents the set frequency control condition. Preferably, [f] = 1.5.

[0017] Preferably, the control frequency f c It should be determined as follows:

[0018] 1) First, select vibration modes with a mode mass participation factor greater than 5% from the vertical vibration parameters of the vertical ring magnetic separator foundation platform obtained in step S1. The selection refers to using the sorting function provided by ANSYS, ABAQUS or SAP2000 general finite element software to arrange all the obtained vibration mode parameters in descending order of mode mass participation factor, and then select the vibration modes with a mode mass participation factor greater than 5%. Alternatively, the selection refers to exporting all the obtained vibration mode parameter data to EXCEL or WPS office software for secondary processing and selecting the vibration modes with a mode mass participation factor greater than 5%.

[0019] 2) Then, from the above vibration modes with a modal mass participation factor greater than 5%, select the vibration modes belonging to the main control region to obtain the vibration modes with a modal mass participation factor greater than 5% in the main control region;

[0020] 3) Finally, the minimum vertical vibration frequency is selected from the vibration modes with a modal mass participation factor greater than 5% in the main control area, and this frequency is used as the control frequency f. c .

[0021] Furthermore, the main control area refers to the area including the foundation of the vertical ring magnetic separator and enclosed by four adjacent pillars.

[0022] Furthermore, if the vertical vibration frequency meets the frequency control conditions, proceed to step S3; if the vertical vibration frequency does not meet the frequency control conditions, proceed to step S4.

[0023] Preferably, the vibration response of the vertical ring magnetic separator foundation platform verified in step S3 satisfies the following expression:

[0024] a≤[a]

[0025] v≤[v]

[0026] d≤[d]

[0027] In the formula, a, v, and d represent the vibration acceleration, vibration velocity, and vibration displacement obtained in step S1, respectively, and [a], [v], and [d] represent the allowable vibration acceleration, allowable vibration velocity, and allowable vibration displacement, respectively, which are the set response control conditions.

[0028] Furthermore, if the vibration response meets the response control conditions, proceed to step S6; otherwise, proceed to step S4.

[0029] Furthermore, the vibration control measure A in step S4 includes: adding columns to the vertical ring magnetic separator foundation platform, adjusting the arrangement of the vertical ring magnetic separator foundation platform beams, and increasing the cross-sectional dimensions of the vertical ring magnetic separator foundation platform beams; the vibration control measure B includes: adjusting the arrangement of the vertical ring magnetic separator foundation platform beams, increasing the cross-sectional dimensions of the vertical ring magnetic separator foundation platform beams, and increasing the thickness of the vertical ring magnetic separator foundation platform plate.

[0030] Furthermore, the verification of the effectiveness of vibration control measures in step S5 refers to: applying the vibration control measures determined in step S4 to the finite element model for analysis, calculating the vertical vibration parameters and vibration response of the vertical ring magnetic separator foundation platform in step S1, and then proceeding to step S2.

[0031] The features and advantages of the embodiments of the present invention are as follows:

[0032] 1. The methods for obtaining the vertical vibration parameters and vibration response of the foundation platform of the vertical ring magnetic separator include finite element calculation and on-site testing, which makes the application scope of the embodiments of the present invention wide, and can be used for vibration control of new projects as well as vibration management of existing projects.

[0033] 2. The embodiments of the present invention adopt a vibration control strategy of "frequency + response" and "frequency first, response later", which is not only comprehensive and clear in its priorities, but also effective and efficient;

[0034] 3. Selecting the vertical vibration frequency with the smallest main control zone mode mass participation factor greater than 5% as the control frequency, and setting the frequency control condition (preferably) to 1.5, is not only highly targeted and in line with engineering practice, but also ensures precise vibration control and high implementation efficiency.

[0035] 4. Using finite element method software to verify the effectiveness of vibration control measures can avoid repeated vibration control, reduce vibration control costs, and minimize adverse impacts on production. Attached Figure Description

[0036] Figure 1 This is a flowchart illustrating the vibration control method for a vertical ring magnetic separator foundation platform provided in an embodiment of the present invention.

[0037] Figure 2 A three-dimensional schematic diagram of finite element model A, which is an application example of an embodiment of the present invention;

[0038] Figure 3 A side view of finite element model A, which is an application example of an embodiment of the present invention;

[0039] Figure 4 A side view of finite element model B, which is an application example of an embodiment of the present invention;

[0040] Figure 5 The seventh mode shape diagram of finite element model B, which is an application example of an embodiment of the present invention;

[0041] Figure 6 The 12th mode shape diagram of finite element model B, which is an application example of an embodiment of the present invention;

[0042] 1 in the figure represents the basic platform of the vertical ring magnetic separator. Detailed Implementation

[0043] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the scope of the present invention.

[0044] Please refer to Figure 1 The present invention provides a vibration control method for a vertical ring magnetic separator foundation platform, comprising the following steps:

[0045] Step S1: Obtain the vertical vibration parameters and vibration response of the vertical ring magnetic separator foundation platform 1. Obtaining the vertical vibration parameters and vibration response of the vertical ring magnetic separator foundation platform includes two methods: finite element calculation and on-site testing. The vertical vibration parameters of the vertical ring magnetic separator foundation platform include the mode shape Φ, frequency f, and mode mass participation factor ψ. The vibration response includes vibration acceleration a, vibration velocity v, and vibration displacement d.

[0046] For example, a workshop has 6 vertical ring magnetic separators arranged on a platform at an elevation of 15.2 meters. Below the 15.2-meter platform is a platform at an elevation of 10.8 meters. There are 7 columns along the length of the workshop and 4 columns along the width of the workshop. A finite element model A is established, as follows: Figure 2 , Figure 3 As shown, after finite element analysis, parameters such as the mode shape Φ, frequency f, and mode mass participation factor ψ of the vertical vibration were obtained, as well as vibration responses such as vibration acceleration a, vibration velocity v, and vibration displacement d.

[0047] Step S2: Verify the vertical vibration frequency of the vertical ring magnetic separator foundation platform according to the following expression:

[0048]

[0049] In the formula, f c f represents the control frequency. e The vibration frequency of the vertical ring magnetic separator is represented by [f] (provided by the vertical ring magnetic separator manufacturer; if it is variable, take the maximum value). [f] represents the set frequency control condition. Preferably, [f] = 1.5.

[0050] Among them, the control frequency f c Determine using the following method:

[0051] 1) First, select vibration modes with a mode mass participation factor greater than 5% from the vertical vibration parameters of the vertical ring magnetic separator foundation platform obtained in step S1;

[0052] 4) Then, from the above vibration modes with a modal mass participation factor greater than 5%, select the vibration modes belonging to the main control region to obtain the vibration modes with a modal mass participation factor greater than 5% in the main control region;

[0053] 5) Finally, the minimum vertical vibration frequency is selected from the vibration modes with a modal mass participation factor greater than 5% in the main control area, and this frequency is used as the control frequency f. c .

[0054] Following the example above, we first screen out vibration modes with a mode mass participation factor greater than 5%: arrange all the vibration mode parameters obtained in step S1 in descending order of mode mass participation factor (the cumulative mass participation factor needs to reach 90%), and take the top five vibration parameters as shown in Table 1.

[0055] Table 1. Vibration parameters ranked by modal mass participation factor.

[0056]

[0057] According to the data in Table 1, the vibration modes with a modal mass participation factor greater than 5% are mode 5, mode 22, mode 11, and mode 45. Among them, only mode 5 is the dominant mode. The frequency of mode 5 is 6.52 Hz, so the controlling frequency f is... c = 6.52 Hz, the vibration frequency f of the vertical ring magnetic separator provided by the manufacturer in this example. e = 5.0 Hz, f c / f e =1.304 < [f]=1.5, proceed with steps S4 and S5 in sequence to reacquire the vertical vibration parameters and vibration response of the vertical ring magnetic separator foundation platform (step S1).

[0058] All the reacquired mode parameters are arranged in descending order of mode mass participation factor (cumulative mass participation factor needs to reach 90%), and the top five vibration parameters are shown in Table 2.

[0059] Table 2. Vibration parameters ranked by modal mass participation factor.

[0060]

[0061] According to the data in Table 2, the vibration modes with a modal mass participation factor greater than 5% are mode 12, mode 7, mode 24, and mode 35. Among them, mode 12 is the dominant mode (e.g., mode 12). Figure 6 (as shown) and the 7th mode (as shown) Figure 5 As shown), the frequency of the 12th mode is 10.28 Hz, and the frequency of the 7th mode is 9.95 Hz. Taking the minimum of the two, the control frequency f is... c = 9.95 Hz, vibration frequency f of vertical ring magnetic separator e = 5.0 Hz, f c / f e =1.99 > [f]=1.5, proceed to step S3.

[0062] Step S3: Check the vibration response of the vertical ring magnetic separator foundation platform according to the following expression:

[0063] a≤[a]

[0064] v≤[v]

[0065] d≤[d]

[0066] In the formula, a, v, and d represent the vibration acceleration, vibration velocity, and vibration displacement obtained in step S1, respectively, and [a], [v], and [d] represent the allowable vibration acceleration, allowable vibration velocity, and allowable vibration displacement, respectively.

[0067] Following the previous example, the vibration response in this example is obtained through finite element analysis. The verification area is the entire vertical ring magnetic separator foundation platform, so the vibration response can be obtained by reading the maximum value (maximum absolute value) from the finite element model, which is convenient and quick. The allowable vibration value is generally provided by the vertical ring magnetic separator manufacturer. In this example, the equipment manufacturer did not provide the allowable vibration value, so the allowable vibration value in this example is determined with reference to relevant national standards. Table 3 shows the maximum vibration response value in this example, and Table 4 shows the allowable vibration value determined with reference to relevant national standards.

[0068] Table 3 Maximum Vibration Response

[0069]

[0070] Table 4 Permissible Vibration Values

[0071]

[0072] Comparing the data in Tables 3 and 4, we can see that the maximum vertical vibration displacement d max =0.291mm > [d]=0.25mm, and the remaining vibration responses are all less than the allowable vibration values. Steps S4 and S5 are performed sequentially to re-acquire the vertical vibration parameters and vibration response of the vertical ring magnetic separator foundation platform (step S1). Step S2 is then performed. Step S2 satisfies the frequency control conditions, and step S3 is then performed. The maximum vibration response values ​​of the vertical ring magnetic separator foundation platform obtained in step S1 are shown in Table 5.

[0073] Table 5 Maximum Vibration Response

[0074]

[0075] Comparing the data in Tables 5 and 4, it can be seen that the vibration response is less than the allowable vibration value, so proceed to step S6.

[0076] Step S4: If the vertical vibration frequency in step S2 does not meet the frequency control conditions, determine vibration control measure A based on the verification results; or, if the vibration response in step S3 does not meet the response control conditions, determine vibration control measure B based on the verification results.

[0077] Following the example above, based on the results of verifying the vertical vibration frequency of the vertical ring magnetic separator foundation platform in step S2: f c / f e =1.304 < [f]=1.5, therefore vibration control measure A should be adopted. After optimization, the vibration control measure A determined in this example is to increase the number of columns on the foundation platform of the vertical ring magnetic separator, that is, in the finite element model A, the foundation platform of the vertical ring magnetic separator has four columns horizontally, such as... Figure 3 As shown, add a column between the second and third columns, as follows: Figure 4 As shown.

[0078] Following the example above, based on the results of verifying the vertical vibration response of the vertical ring magnetic separator foundation platform in step S3: the maximum vertical vibration displacement d max =0.291mm > [d]=0.25mm, therefore vibration control measure B should be adopted. In this example, the maximum vertical vibration displacement occurs in the main control area. After optimization, the vibration control measure B determined in this example is to increase the plate thickness in the main control area, that is, to increase the plate thickness in the main control area from the original 150mm to 400mm.

[0079] Step S5: Verify the effectiveness of the vibration control measures. Verifying the effectiveness of the vibration control measures means: applying the vibration control measures determined in step S4 to the finite element model for analysis, calculating the vertical vibration parameters and vibration response of the vertical ring magnetic separator foundation platform (step S1), and then proceeding to step S2.

[0080] Following the example above, based on the verification results of step S2, vibration control measure A is adopted, namely, adding columns to the foundation platform of the vertical ring magnetic separator. The above measures are applied to the finite element model B for analysis, and the vertical vibration parameters and vibration response of the foundation platform of the vertical ring magnetic separator are calculated (step S1). Then, step S2 is performed.

[0081] Following the example above, based on the vibration control measure B adopted according to the verification results of step S3, namely increasing the thickness of the main control area plate, the above measures are applied to the finite element model C for analysis, and the vertical vibration parameters and vibration response of the vertical ring magnetic separator foundation platform are calculated (step S1), and then step S2 is performed.

[0082] Step S6: Repeat the process of "checking, determining vibration control measures and verifying effectiveness" in steps S2, S3, S4, S5 and S1 above until the set frequency and response control conditions are met.

[0083] Following the example above, after steps S1-S2-S4-S5-S1-S2-S3-S4-S5-S1-S2-S3, the vertical vibration frequency and vibration response of the vertical ring magnetic separator base platform both meet the set control conditions, and the vibration control process ends.

Claims

1. A vibration control method for a foundation platform of a vertical ring magnetic separator, characterized in that, Includes the following steps: S1. Obtain the vertical vibration parameters and vibration response of the vertical ring magnetic separator foundation platform; S2. Check the vertical vibration frequency of the vertical ring magnetic separator base platform. If the vertical vibration frequency meets the frequency control conditions, proceed to step S3; otherwise, proceed to step S4. S3. Check the vibration response of the vertical ring magnetic separator foundation platform. If the vibration response meets the response control conditions, proceed to step S6; otherwise, proceed to step S4. S4. If the vertical vibration frequency in step S2 does not meet the frequency control conditions, determine vibration control measure A based on the verification results; or, if the vibration response in step S3 does not meet the response control conditions, determine vibration control measure B based on the verification results. S5. Verify the effectiveness of the vibration control measures; S6. Once the "frequency + response" control conditions are met, the vibration control process ends.

2. The vibration control method for a vertical ring magnetic separator foundation platform according to claim 1, characterized in that: The acquisition of vertical vibration parameters and vibration response of the vertical ring magnetic separator foundation platform in step S1 includes two methods: finite element analysis (FEM) or on-site testing. FEM is used for vibration control in new projects or to verify the effectiveness of vibration control measures, while on-site testing is used for vibration mitigation of existing vertical ring magnetic separator foundation platforms. FEM uses general-purpose finite element software such as ANSYS, ABAQUS, or SAP2000; on-site testing uses a multi-channel data acquisition instrument, vibration sensors, and the accompanying "DASP - Intelligent Data Acquisition and Signal Processing System" software.

3. The vibration control method for a vertical ring magnetic separator foundation platform according to claim 1, characterized in that: The vertical vibration parameters of the vertical ring magnetic separator foundation platform in step S1 include the mode shape, frequency, and mode mass participation coefficient of vertical vibration, and the vibration response includes vibration acceleration, vibration velocity, and vibration displacement.

4. The vibration control method for a vertical ring magnetic separator foundation platform according to claim 1, characterized in that: The vertical vibration frequency of the foundation platform of the vertical ring magnetic separator mentioned in step S2 should satisfy the following expression: ； In the formula, f c f represents the control frequency. e [f] represents the vibration frequency of the vertical ring magnetic separator (provided by the vertical ring magnetic separator manufacturer; if it is variable, take the maximum value), and [f] represents the set frequency control conditions.

5. The vibration control method for a vertical ring magnetic separator foundation platform according to claim 1, characterized in that: Control frequency f c It should be determined as follows: 1) First, select vibration modes with a mode mass participation factor greater than 5% from the vertical vibration parameters of the vertical ring magnetic separator foundation platform obtained in step S1. The selection refers to using the sorting function provided by ANSYS, ABAQUS or SAP2000 general finite element software to arrange all the obtained vibration mode parameters in descending order of mode mass participation factor, and then select the vibration modes with a mode mass participation factor greater than 5%. Alternatively, the selection refers to exporting all the obtained vibration mode parameter data to EXCEL or WPS office software for secondary processing and selecting the vibration modes with a mode mass participation factor greater than 5%. 2) Then, from the above vibration modes with a modal mass participation factor greater than 5%, select the vibration modes belonging to the main control region to obtain the vibration modes with a modal mass participation factor greater than 5% in the main control region; 3) Finally, the minimum vertical vibration frequency is selected from the vibration modes with a modal mass participation factor greater than 5% in the main control area, and this frequency is used as the control frequency f. c .

6. The vibration control method for a vertical ring magnetic separator foundation platform according to claim 5, characterized in that: The main control area refers to the area including the foundation of the vertical ring magnetic separator and enclosed by four adjacent pillars.

7. The vibration control method for a vertical ring magnetic separator foundation platform according to claim 1, characterized in that: In step S3, the vibration response of the vertical ring magnetic separator foundation platform is verified to satisfy the following expression: a≤[a] v≤[v] d≤[d] In the formula, a, v, and d represent the vibration acceleration, vibration velocity, and vibration displacement obtained in step S1, respectively, and [a], [v], and [d] represent the allowable vibration acceleration, allowable vibration velocity, and allowable vibration displacement, respectively, which are the set response control conditions.

8. The vibration control method for a vertical ring magnetic separator foundation platform according to claim 1, characterized in that: The vibration control measure A in step S4 includes: adding columns to the vertical ring magnetic separator foundation platform, adjusting the arrangement of the vertical ring magnetic separator foundation platform beams, and increasing the cross-sectional dimensions of the vertical ring magnetic separator foundation platform beams; the vibration control measure B includes: adjusting the arrangement of the vertical ring magnetic separator foundation platform beams, increasing the cross-sectional dimensions of the vertical ring magnetic separator foundation platform beams, and increasing the thickness of the vertical ring magnetic separator foundation platform plate.

9. The vibration control method for a vertical ring magnetic separator foundation platform according to claim 1, characterized in that: The verification of the effectiveness of vibration control measures in step S5 refers to: applying the vibration control measures determined in step S4 to the finite element model for analysis, calculating the vertical vibration parameters and vibration response of the vertical ring magnetic separator foundation platform (step S1), and then proceeding to step S2.

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