Centrifugal fan bearing life assessment method and system

Abstract

This invention discloses a method and system for assessing the lifespan of centrifugal fan bearings, belonging to the technical field of bearing life assessment. It retrieves the number of times the centrifugal fan stops, the corresponding time points of each stop, and the stop duration within a sampling time period, and simultaneously collects dust concentration data from the external and internal bearing cavities of the centrifugal fan. It calculates the dust intrusion efficiency coefficient of the centrifugal fan from a single stop to the end of the stop within a single sampling time period, and calculates the predicted duration of fretting wear life reduction from a single stop to the end of the stop within a single sampling time period. Based on the predicted duration of fretting wear life reduction, it calculates the cumulative value of the predicted duration of fretting wear life reduction within a single sampling time period. It presets a threshold for the cumulative predicted duration, analyzes the data, and issues early warnings, achieving accurate assessment and dynamic pre-control of bearing life status, effectively improving the reliability of equipment operation and the level of intelligent operation and maintenance.

Description

Technical Field

[0001] This invention relates to the field of bearing life assessment technology, specifically to a method and system for assessing the life of centrifugal fan bearings. Background Technology

[0002] Centrifugal fans are key equipment in industrial ventilation, air conditioning systems, and environmental management, and their operating status directly affects the overall stability and energy efficiency of the system. Especially in high-dust environments, bearings, as crucial supporting components of the fan, bear enormous loads and complex working stresses, making them a key factor influencing the fan's lifespan and reliability. With the advancement of intelligent industrial equipment and refined maintenance management, research on fan bearing condition monitoring, lifespan prediction, and risk assessment has gradually emerged. Current research attempts to indirectly judge the bearing's operating status using physical indicators such as temperature rise and vibration, while some literature proposes constructing a rough lifespan assessment mechanism based on bearing material fatigue models or operating time. However, due to the complex operating conditions of fans, such as frequent start-stop cycles, load changes, and particulate intrusion, traditional assessment methods based on time or temperature thresholds are insufficient to accurately reflect the actual wear mechanism, especially in addressing the rapid reduction in bearing life caused by fretting wear.

[0003] Current technologies lack a dynamic coupling modeling mechanism for the dust intrusion effect and fretting wear during centrifugal fan bearing operation, making it difficult to quantitatively characterize the specific wear trend of the fan within the sampling period. Most methods fail to combine shutdown behavior with the post-shutdown pollution evolution characteristics, ignoring the delayed intrusion and accumulation effect of dust on the bearing cavity under static conditions, leading to deviations in bearing life assessment results under critical operating conditions. Furthermore, existing monitoring systems largely rely on manual periodic maintenance and inspection, resulting in delayed early warning responses and a lack of predictive mechanisms and quantitative judgment standards based on actual operating data. Summary of the Invention

[0004] The purpose of this invention is to provide a method and system for assessing the lifespan of centrifugal fan bearings, in order to solve the problems mentioned in the background art.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0006] A method for assessing the bearing life of a centrifugal fan includes the following steps: Step S1: Retrieve the number of times the centrifugal fan stops, the corresponding time point and duration of each stop within a sampling time period, and simultaneously collect dust concentration data of the external and internal bearing cavities of the centrifugal fan; Step S2: Based on the external dust concentration data and internal bearing cavity dust concentration data of the centrifugal fan during a single stop and after the stop within a single sampling time period, calculate the dust intrusion efficiency coefficient of the centrifugal fan from the start of a single stop to the end of the stop within a single sampling time period; Step S3: Based on the dust intrusion efficiency coefficient of the centrifugal fan, calculate the predicted duration of fretting wear life reduction from the start of a single stop within a single sampling time period; Step S4: Based on the predicted duration of fretting wear life reduction, calculate the cumulative value of the predicted duration of fretting wear life reduction within a single sampling time period; preset a threshold for the cumulative predicted duration, analyze and issue an early warning.

[0007] As a preferred embodiment of the centrifugal fan bearing life assessment method described in this invention, a sampling time period is set, and the operating condition data of the centrifugal fan is periodically retrieved from the background of the centrifugal fan operation control system. The operating condition data includes the number of times the centrifugal fan stops within the sampling time period, the time point corresponding to each stop, and the stop duration; the i-th sampling time period is denoted as TF. i Let TP be the time point and duration corresponding to the a-th shutdown of the centrifugal fan within the i-th sampling time period. a (TF i ) and DOD a (TF i );

[0008] Dust concentration sensors are installed on the exterior and inside the bearing cavity of the centrifugal fan. Dust concentration data from the exterior and inside the bearing cavity are collected synchronously at the time corresponding to each fan shutdown and at the time after each shutdown. The time point after the a-th shutdown within the i-th sampling period is recorded as ED. a (TF i ), where ED a (TF i ) = TP a (TF i )+DOD a (TF i ).

[0009] It should be noted that each shutdown time point marks the critical moment when dust begins to infiltrate; the shutdown duration is the core parameter determining the dust accumulation time; external dust concentration data reflects the environmental dust level; and internal bearing cavity dust concentration data is an indicator for directly monitoring the degree of seal failure. External dust concentration data reflects the severity of the environment, while internal bearing cavity dust concentration data is directly related to the risk of bearing contamination. Traditional methods monitor vibration and temperature data during operation, but when the centrifugal fan is shut down, the bearing cavity is prone to drawing in external dust due to the negative pressure effect, making dust intrusion more likely.

[0010] As a preferred embodiment of the centrifugal fan bearing life assessment method of the present invention, the dust concentration data of the external and internal bearing cavities corresponding to the a-th shutdown of the centrifugal fan within the i-th sampling time period are respectively denoted as EDC[TP]. a (TF i )] and IDC[TP a (TF i The dust concentration data of the external and internal bearing cavities of the centrifugal fan after the a-th shutdown within the i-th sampling time period are respectively denoted as EDC[ED]. a (TF i )] and IDC[ED a (TF i )];

[0011] Based on the external dust concentration data EDC[TP] corresponding to the a-th shutdown of the centrifugal fan within the i-th sampling time period. a (TF i Data on dust concentration in the internal bearing cavity (IDC[TP]) a (TF i The external dust concentration data EDC[ED] after the centrifugal fan stops for the a-th time during the i-th sampling period. a (TF i Data on dust concentration in the internal bearing cavity (IDC) a (TF i )] Calculate the dust intrusion efficiency coefficient of the centrifugal fan from the a-th shutdown to the end of the shutdown within the i-th sampling time period.

[0012] As a preferred embodiment of the centrifugal fan bearing life assessment method of the present invention, the specific implementation process of the dust intrusion efficiency coefficient of the inner and outer cavities of the centrifugal fan includes:

[0013] Based on the external dust concentration data EDC[TP] corresponding to the a-th shutdown of the centrifugal fan within the i-th sampling time period. a (TF iExternal dust concentration data (EDC) after the a-th shutdown. a (TF i ], calculate the average external dust concentration from the a-th shutdown of the centrifugal fan during the i-th sampling time period to the end of the shutdown, denoted as . in,

[0014] Based on the average external dust concentration from the a-th shutdown of the centrifugal fan during the i-th sampling time period to the end of the shutdown. The dust intrusion efficiency coefficient of the centrifugal fan from the a-th shutdown to the end of the shutdown within the i-th sampling time period is calculated using the following formula:

[0015]

[0016] Where, η a (TF i ) represents the dust intrusion efficiency coefficient of the centrifugal fan from the a-th shutdown to the end of the shutdown within the i-th sampling time period.

[0017] It should be noted that molecular IDC[ED] a (TF i )]-IDC[TP a (TF i The ratio of the two values ​​represents the increase in dust concentration within the internal bearing cavity during shutdown, with the denominator being the average external dust concentration. The ratio reflects the efficiency of external dust penetrating the sealing structure and entering the interior. The dust intrusion efficiency coefficient η between the internal and external cavities of the centrifugal fan is also shown. a (TF i The higher the value, the greater the proportion of dust intrusion relative to the external concentration, indicating poorer bearing sealing performance or a higher risk of environmental dust intrusion. This formula establishes a quantitative indicator of dust intrusion, which can directly correlate the external environment with the degree of internal bearing contamination.

[0018] As a preferred embodiment of the centrifugal fan bearing life assessment method described in this invention, the method is based on the dust intrusion efficiency coefficient η of the centrifugal fan's internal and external cavities from the a-th shutdown to the end of the shutdown within the i-th sampling time period. a (TF i The predicted duration of fretting wear life reduction for the centrifugal fan from the a-th shutdown within the i-th sampling time period to the end of the shutdown is calculated as follows:

[0019] Preset threshold for dust intrusion efficiency coefficient η in internal and external cavities cri If the efficiency coefficient η of dust intrusion into the inner and outer cavities of the centrifugal fan a (TF i The efficiency coefficient threshold η for dust intrusion into the internal and external cavities is greater than or equal to that threshold.cri If the centrifugal fan is determined to have high dust intrusion efficiency in its internal and external cavities during the a-th shutdown within the i-th sampling time period, then the predicted duration of fretting wear life reduction for the centrifugal fan during the a-th shutdown within the i-th sampling time period is calculated using the following formula:

[0020] ΔWRT i,a =α×DOD a (TF i )×[η a (TF i )-η cri ];

[0021] Among them, ΔWRT i,a α represents the predicted duration of fretting wear life reduction from the a-th shutdown to the end of the shutdown within the i-th sampling time period, and α represents the preset wear rate coefficient.

[0022] It should be noted that when the dust intrusion efficiency coefficient η in the inner and outer cavities of the centrifugal fan... a (TF i The dust intrusion efficiency coefficient threshold η of the internal and external cavities is exceeded. cri At this point, dust intrusion is considered to have reached a level that significantly accelerates fretting wear, thus avoiding misjudging normal dust intrusion (below the wear threshold) as a risk and reducing the false alarm rate. The formula multiplies the portion of the intrusion efficiency exceeding the threshold by the downtime DOD. a (TF i The wear rate coefficient α) predicts the time it takes for dust intrusion to translate into reduced lifespan, where α × DOD a (TF i This can be understood as the basic wear amount, [η] a (TF i )-η cri This can be understood as an efficiency penalty, meaning the more you exceed the limit, the faster the damage occurs.

[0023] As a preferred embodiment of the centrifugal fan bearing life assessment method described in this invention, the prediction time ΔWRT is based on the fretting wear life reduction from the a-th shutdown to the end of the shutdown within the i-th sampling time period. i,a Calculate the cumulative value of the predicted duration of fretting wear life reduction for the centrifugal fan during the i-th sampling time period, denoted as . in, A represents the total number of times the centrifugal fan stops during the i-th sampling time period;

[0024] It should be noted that this is the cumulative value of the predicted duration of fretting wear life reduction, not the average value. It emphasizes the cumulative effect of high-frequency shutdowns. For example, five short shutdowns in one day are more dangerous than one long shutdown.

[0025] A preset threshold for the cumulative predicted duration of fretting wear life reduction is set. If the cumulative predicted duration of fretting wear life reduction for the centrifugal fan during the i-th sampling time period is... If the cumulative value of the predicted duration of fretting wear reduction is greater than or equal to the threshold value, it is determined that the centrifugal fan has an abnormal reduction in lifespan during the i-th sampling time period. In this case, an early warning is issued and relevant personnel are notified to perform shutdown maintenance.

[0026] A centrifugal fan bearing life assessment system, comprising: a data acquisition module, a dust intrusion efficiency coefficient calculation module, a life reduction duration prediction module, and a life reduction duration cumulative value calculation, analysis, and early warning module;

[0027] The data acquisition module retrieves the number of times the centrifugal fan stops during the sampling time period, the time point corresponding to each stop, and the stop duration, and simultaneously collects dust concentration data of the external and internal bearing cavities of the centrifugal fan.

[0028] The dust intrusion efficiency coefficient calculation module calculates the dust intrusion efficiency coefficient of the centrifugal fan from the moment of shutdown to the moment of shutdown within a single sampling time period, based on the external dust concentration data and the internal bearing cavity dust concentration data of the centrifugal fan during a single shutdown and after the shutdown within a single sampling time period.

[0029] The life reduction prediction module calculates the predicted duration of fretting wear life reduction of the centrifugal fan from a single shutdown to the end of the shutdown within a single sampling time period, based on the dust intrusion efficiency coefficient of the inner and outer cavities of the centrifugal fan.

[0030] The cumulative life reduction duration calculation and analysis early warning module calculates the cumulative value of the predicted life reduction duration of the centrifugal fan within a single sampling time period based on the predicted life reduction duration of the fretting wear; presets a threshold value for the cumulative predicted duration, analyzes and issues an early warning.

[0031] Furthermore, the dust intrusion efficiency coefficient calculation module includes a dust intrusion efficiency coefficient calculation unit;

[0032] The dust intrusion efficiency coefficient calculation unit calculates the dust intrusion efficiency coefficient of the centrifugal fan from the a-th shutdown to the end of the shutdown within the i-th sampling time period, based on the external dust concentration data and internal bearing cavity dust concentration data corresponding to the a-th shutdown of the centrifugal fan within the i-th sampling time period.

[0033] Furthermore, the lifetime reduction prediction module includes a lifetime reduction prediction unit;

[0034] The lifespan reduction prediction unit calculates the predicted fretting wear lifespan reduction time based on the dust intrusion efficiency coefficient of the centrifugal fan from the a-th shutdown to the end of the shutdown within the i-th sampling time period. The details are as follows:

[0035] A preset threshold for the dust intrusion efficiency coefficient of the inner and outer cavities is set. If the dust intrusion efficiency coefficient of the inner and outer cavities of the centrifugal fan is greater than or equal to the threshold, it is determined that the dust intrusion efficiency of the inner and outer cavities of the centrifugal fan is high from the a-th shutdown in the i-th sampling time period to the end of the shutdown. Then, the predicted duration of the fretting wear life reduction of the centrifugal fan from the a-th shutdown in the i-th sampling time period to the end of the shutdown is calculated.

[0036] Furthermore, the cumulative lifespan reduction calculation and analysis early warning module includes a cumulative lifespan reduction calculation unit and an analysis and early warning unit;

[0037] The cumulative life reduction time calculation unit calculates the cumulative value of the fretting wear life reduction prediction time of the centrifugal fan in the i-th sampling time period based on the fretting wear life reduction prediction time from the a-th shutdown to the end of the shutdown in the i-th sampling time period.

[0038] The analysis and early warning unit: presets a threshold value for the cumulative predicted duration of fretting wear life reduction. If the cumulative predicted duration of fretting wear life reduction of the centrifugal fan in the i-th sampling time period is greater than or equal to the threshold value, it is determined that the centrifugal fan has an abnormal life reduction in the i-th sampling time period, and an early warning is issued and relevant personnel are notified to shut down the machine for maintenance.

[0039] Compared with existing technologies, the beneficial effects achieved by this invention are as follows: The centrifugal fan bearing life assessment method and system provided by this invention, by setting a sampling time period, collects the number of shutdowns, shutdown times, and shutdown durations of the centrifugal fan within the period, and simultaneously acquires dust concentration data from both the external and internal bearing cavities, achieving dynamic perception of operating conditions and the polluted environment. Based on this, the dust intrusion efficiency coefficient of the internal and external cavities during each shutdown process is calculated, quantifying the actual intrusion intensity of external dust on the bearing structure, thus providing a key basis for judging the trend of fretting wear reduction. Furthermore, based on the dust intrusion efficiency, the predicted life reduction duration after a single shutdown is calculated, constructing a quantitative mapping relationship between external pollution and internal failure. Finally, the cumulative value of multiple predicted durations within the period is used to judge the life change trend; if it exceeds a preset threshold, an early warning is triggered, prompting maintenance operations. This method, by constructing a closed-loop mechanism between shutdown behavior, pollution intrusion, wear process, and life warning, achieves accurate assessment and dynamic pre-control of bearing life status, effectively improving the reliability of equipment operation and the level of intelligent operation and maintenance. Attached Figure Description

[0040] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof.

[0041] Figure 1 This is a schematic diagram of the steps in the centrifugal fan bearing life assessment method of the present invention;

[0042] Figure 2 This is a schematic diagram of the structure of a centrifugal fan bearing life assessment system according to the present invention. Detailed Implementation

[0043] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0044] Please see Figure 1 In this first embodiment: a method for assessing the lifespan of a centrifugal fan bearing is provided, the method comprising the following steps:

[0045] Step S1: Retrieve the number of times the centrifugal fan stops during the sampling time period, the time point corresponding to each stop, and the stop duration, and simultaneously collect dust concentration data of the external and internal bearing cavities of the centrifugal fan.

[0046] Specifically, a sampling time period is set, and the operating condition data of the centrifugal fan is periodically retrieved from the background of the centrifugal fan operation control system. The operating condition data includes the number of times the centrifugal fan stops within the sampling time period, the time point corresponding to each stop, and the stop duration; the i-th sampling time period is denoted as TF. i Let TP be the time point and duration corresponding to the a-th shutdown of the centrifugal fan within the i-th sampling time period. a (TF i ) and DOD a (TF i );

[0047] Furthermore, dust concentration sensors are installed both outside and inside the bearing cavity of the centrifugal fan. Dust concentration data from the external and internal bearing cavities are simultaneously collected at the time corresponding to each stop of the centrifugal fan and at the time point after each stop. The time point after the a-th stop within the i-th sampling time period is recorded as ED. a (TF i ), where ED a (TF i ) = TP a (TF i )+DOD a (TF i ).

[0048] Step S2: Based on the external dust concentration data and internal bearing cavity dust concentration data of the centrifugal fan during a single stop and after the end of the stop within a single sampling time period, calculate the dust intrusion efficiency coefficient of the centrifugal fan from the single stop to the end of the stop within a single sampling time period.

[0049] Specifically, the dust concentration data of the external and internal bearing cavities corresponding to the a-th shutdown of the centrifugal fan within the i-th sampling time period are denoted as EDC[TP]. a (TF i )] and IDC[TP a (TF i The dust concentration data of the external and internal bearing cavities of the centrifugal fan after the a-th shutdown within the i-th sampling time period are respectively denoted as EDC[ED]. a (TF i )] and IDC[ED a (TF i )];

[0050] Furthermore, based on the external dust concentration data EDC[TP] corresponding to the a-th shutdown of the centrifugal fan within the i-th sampling time period, a (TF iData on dust concentration in the internal bearing cavity (IDC[TP]) a (TF i The external dust concentration data EDC[ED] after the centrifugal fan stops for the a-th time during the i-th sampling period. a (TF i Data on dust concentration in the internal bearing cavity (IDC) a (TF i The dust intrusion efficiency coefficients of the centrifugal fan from the a-th shutdown to the end of the shutdown within the i-th sampling time period are calculated as follows:

[0051] Based on the external dust concentration data EDC[TP] corresponding to the a-th shutdown of the centrifugal fan within the i-th sampling time period. a (TF i External dust concentration data (EDC) after the a-th shutdown. a (TF i ], calculate the average external dust concentration from the a-th shutdown of the centrifugal fan during the i-th sampling time period to the end of the shutdown, denoted as . in,

[0052] Furthermore, based on the average external dust concentration from the a-th shutdown of the centrifugal fan during the i-th sampling time period to the end of the shutdown... The dust intrusion efficiency coefficient of the centrifugal fan from the a-th shutdown to the end of the shutdown within the i-th sampling time period is calculated using the following formula:

[0053]

[0054] Where, η a (TF i ) represents the dust intrusion efficiency coefficient of the centrifugal fan from the a-th shutdown to the end of the shutdown within the i-th sampling time period.

[0055] Step S3: Based on the dust intrusion efficiency coefficient of the inner and outer cavities of the centrifugal fan, calculate the predicted time of fretting wear life reduction of the centrifugal fan from the end of a single shutdown within a single sampling time period.

[0056] Specifically, the dust intrusion efficiency coefficient η of the centrifugal fan's internal and external cavities is based on the period from the a-th shutdown of the centrifugal fan during the i-th sampling time period to the end of the shutdown. a (TF i The predicted duration of fretting wear life reduction for the centrifugal fan from the a-th shutdown within the i-th sampling time period to the end of the shutdown is calculated as follows:

[0057] Preset threshold for dust intrusion efficiency coefficient η in internal and external cavities cri If the efficiency coefficient η of dust intrusion into the inner and outer cavities of the centrifugal fan a (TF i The efficiency coefficient threshold η for dust intrusion into the internal and external cavities is greater than or equal to that threshold. cri If the centrifugal fan is determined to have high dust intrusion efficiency in its internal and external cavities during the a-th shutdown within the i-th sampling time period, then the predicted duration of fretting wear life reduction for the centrifugal fan during the a-th shutdown within the i-th sampling time period is calculated using the following formula:

[0058] ΔWRT i,a =α×DOD a (TF i )×[η a (TF i )-η cri ];

[0059] Among them, ΔWRT i,a α represents the predicted duration of fretting wear life reduction from the a-th shutdown to the end of the shutdown within the i-th sampling time period, and α represents the preset wear rate coefficient.

[0060] Step S4: Based on the predicted duration of fretting wear life reduction, calculate the cumulative value of the predicted duration of fretting wear life reduction of the centrifugal fan within a single sampling time period; preset the threshold value of the cumulative predicted duration, analyze and issue an early warning.

[0061] Specifically, the predicted duration ΔWRT of fretting wear life reduction is based on the a-th shutdown of the centrifugal fan within the i-th sampling time period, from the end of the shutdown to the end of the shutdown. i,a Calculate the cumulative value of the predicted duration of fretting wear life reduction for the centrifugal fan during the i-th sampling time period, denoted as . in, A represents the total number of times the centrifugal fan stops during the i-th sampling time period;

[0062] Furthermore, a threshold value for the cumulative predicted duration of fretting wear life reduction is preset. If the cumulative predicted duration of fretting wear life reduction of the centrifugal fan in the i-th sampling time period is... If the cumulative value of the predicted duration of fretting wear reduction is greater than or equal to the threshold value, it is determined that the centrifugal fan has an abnormal reduction in lifespan during the i-th sampling time period. In this case, an early warning is issued and relevant personnel are notified to perform shutdown maintenance.

[0063] Please see Figure 2In this second embodiment: a centrifugal fan bearing life assessment system is provided, which includes: a data acquisition module, a dust intrusion efficiency coefficient calculation module, a life reduction duration prediction module, and a life reduction duration cumulative value calculation, analysis and early warning module;

[0064] The data acquisition module retrieves the number of times the centrifugal fan stops during the sampling time period, the time point corresponding to each stop, and the stop duration, and simultaneously collects dust concentration data of the external and internal bearing cavities of the centrifugal fan.

[0065] The dust intrusion efficiency coefficient calculation module calculates the dust intrusion efficiency coefficient of the centrifugal fan from the moment of shutdown to the moment of shutdown within a single sampling time period, based on the external dust concentration data and the internal bearing cavity dust concentration data of the centrifugal fan during a single shutdown and after the shutdown within a single sampling time period.

[0066] The life reduction prediction module calculates the predicted duration of fretting wear life reduction of the centrifugal fan from a single shutdown to the end of the shutdown within a single sampling time period, based on the dust intrusion efficiency coefficient of the inner and outer cavities of the centrifugal fan.

[0067] The cumulative life reduction duration calculation and analysis early warning module calculates the cumulative value of the predicted life reduction duration of the centrifugal fan within a single sampling time period based on the predicted life reduction duration of the fretting wear; presets a threshold value for the cumulative predicted duration, analyzes and issues an early warning.

[0068] Furthermore, the dust intrusion efficiency coefficient calculation module includes a dust intrusion efficiency coefficient calculation unit;

[0069] The dust intrusion efficiency coefficient calculation unit calculates the dust intrusion efficiency coefficient of the centrifugal fan from the a-th shutdown to the end of the shutdown within the i-th sampling time period, based on the external dust concentration data and internal bearing cavity dust concentration data corresponding to the a-th shutdown of the centrifugal fan within the i-th sampling time period.

[0070] Furthermore, the lifetime reduction prediction module includes a lifetime reduction prediction unit;

[0071] The lifespan reduction prediction unit calculates the predicted fretting wear lifespan reduction time based on the dust intrusion efficiency coefficient of the centrifugal fan from the a-th shutdown to the end of the shutdown within the i-th sampling time period. The details are as follows:

[0072] A preset threshold for the dust intrusion efficiency coefficient of the inner and outer cavities is set. If the dust intrusion efficiency coefficient of the inner and outer cavities of the centrifugal fan is greater than or equal to the threshold, it is determined that the dust intrusion efficiency of the inner and outer cavities of the centrifugal fan is high from the a-th shutdown in the i-th sampling time period to the end of the shutdown. Then, the predicted duration of the fretting wear life reduction of the centrifugal fan from the a-th shutdown in the i-th sampling time period to the end of the shutdown is calculated.

[0073] Furthermore, the cumulative lifespan reduction calculation and analysis early warning module includes a cumulative lifespan reduction calculation unit and an analysis and early warning unit;

[0074] The cumulative life reduction time calculation unit calculates the cumulative value of the fretting wear life reduction prediction time of the centrifugal fan in the i-th sampling time period based on the fretting wear life reduction prediction time from the a-th shutdown to the end of the shutdown in the i-th sampling time period.

[0075] The analysis and early warning unit: presets a threshold value for the cumulative predicted duration of fretting wear life reduction. If the cumulative predicted duration of fretting wear life reduction of the centrifugal fan in the i-th sampling time period is greater than or equal to the threshold value, it is determined that the centrifugal fan has an abnormal life reduction in the i-th sampling time period, and an early warning is issued and relevant personnel are notified to shut down the machine for maintenance.

[0076] Please refer to Tables 1 and 2. In this third embodiment, a method for evaluating the life of centrifugal fan bearings is provided. To verify the beneficial effects of the present invention, a simulation experiment is conducted for scientific demonstration.

[0077] Assuming a sampling period of 1 day (24 hours), the total number of shutdowns A of the centrifugal fan during the first sampling period is 2, and the preset wear rate coefficient α = 0.1h. -1 The preset threshold value for dust intrusion efficiency coefficient η in the inner and outer cavities cri It is 0.3.

[0078] Table 1. Downtime Event Data

[0079]

[0080] Table 2 Dust Concentration Data

[0081]

[0082] Substituting into the formula, we can see that the average external dust concentration of the centrifugal fan from the first shutdown to the end of the shutdown period within the first sampling time cycle is...

[0083] The average external dust concentration of the centrifugal fan from the second shutdown within the first sampling period to the end of the shutdown period.

[0084] The dust intrusion efficiency coefficient of the centrifugal fan from the first shutdown to the end of the first shutdown period within the first sampling time period.

[0085] The dust intrusion efficiency coefficient of the centrifugal fan from the second shutdown within the first sampling period to the end of the shutdown.

[0086] For the first shutdown of the centrifugal fan within the first sampling time period:

[0087] The predicted duration ΔWRT for the reduction of fretting wear life of the centrifugal fan from the first shutdown within the first sampling time period to the end of the shutdown is then calculated. 1,1 =0.1×2×[0.444-0.3]=0.2×0.144=0.0288h;

[0088] For the second shutdown of the centrifugal fan within the first sampling time period:

[0089] The predicted duration ΔWRT for the reduction of fretting wear life of the centrifugal fan from the second shutdown within the first sampling time period to the end of the shutdown is then calculated. 1,1 =0.1×3×[0.414-0.3]=0.3×0.114=0.0342h;

[0090] Cumulative value of predicted duration of fretting wear life reduction for centrifugal fan during the first sampling period

[0091] Assuming the threshold for the cumulative predicted duration of fretting wear life reduction is 0.05h, then the cumulative predicted duration of fretting wear life reduction for the centrifugal fan during the first sampling time period is... If it is determined that the centrifugal fan has an abnormal reduction in lifespan during the first sampling time period, an early warning will be issued and relevant personnel will be notified to shut down the machine for maintenance.

[0092] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0093] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method of evaluating the lifetime of a centrifugal fan bearing, characterized in that, The method includes the following steps: Step S1: Set a sampling time period and periodically retrieve the operating condition data of the centrifugal fan from the background of the centrifugal fan operation control system. The operating condition data includes the number of times the centrifugal fan stops within the sampling time period, the time point corresponding to each stop, and the stop duration; denoted as the i-th sampling time period. Let the time point and downtime of the centrifugal fan during the a-th downtime within the i-th sampling period be denoted as . and ; Dust concentration sensors are installed both outside and inside the bearing cavity of the centrifugal fan. Dust concentration data from the external and internal bearing cavities are simultaneously collected at the time corresponding to each fan shutdown and at the time point after each shutdown. The time point after the a-th shutdown within the i-th sampling time period is recorded as... ,in, ; Step S2: Based on the external dust concentration data and internal bearing cavity dust concentration data of the centrifugal fan during a single stop and after the end of the stop within a single sampling time period, calculate the dust intrusion efficiency coefficient of the centrifugal fan from the single stop to the end of the stop within a single sampling time period. Step S3: Based on the dust intrusion efficiency coefficient of the inner and outer cavities of the centrifugal fan, calculate the predicted time of fretting wear life reduction of the centrifugal fan from the end of a single shutdown within a single sampling time period; Step S4: Based on the predicted duration of fretting wear life reduction, calculate the cumulative value of the predicted duration of fretting wear life reduction of the centrifugal fan within a single sampling time period; preset the threshold value of the cumulative predicted duration, analyze and issue an early warning; The specific implementation process for calculating the dust intrusion efficiency coefficient of the centrifugal fan from the end of a single shutdown within a single sampling time period includes: Based on the external dust concentration data corresponding to the a-th shutdown of the centrifugal fan within the i-th sampling time period. External dust concentration data after the a-th shutdown Calculate the average external dust concentration from the a-th shutdown of the centrifugal fan during the i-th sampling time period until the end of the shutdown, denoted as . ,in, ; Based on the average external dust concentration from the a-th shutdown of the centrifugal fan during the i-th sampling time period to the end of the shutdown. The dust intrusion efficiency coefficient of the centrifugal fan from the a-th shutdown to the end of the shutdown within the i-th sampling time period is calculated using the following formula: ； in, This represents the dust intrusion efficiency coefficient of the centrifugal fan from the a-th shutdown to the end of the shutdown within the i-th sampling time period. This represents the dust concentration data in the internal bearing cavity corresponding to the a-th shutdown of the centrifugal fan within the i-th sampling time period. This represents the dust concentration data in the internal bearing cavity of the centrifugal fan after the a-th shutdown within the i-th sampling time period; The specific implementation process of step S3 includes: Based on the dust intrusion efficiency coefficient of the centrifugal fan from the a-th shutdown to the end of the shutdown within the i-th sampling time period. The predicted duration of fretting wear life reduction from the a-th shutdown to the end of the shutdown within the i-th sampling time period is calculated as follows: Preset threshold for dust intrusion efficiency coefficient in internal and external cavities If dust enters the inner and outer cavities of the centrifugal fan, the efficiency coefficient Greater than or equal to the threshold of dust intrusion efficiency coefficient in the inner and outer cavities If the centrifugal fan is determined to have high dust intrusion efficiency in its internal and external cavities during the a-th shutdown within the i-th sampling time period, then the predicted duration of fretting wear life reduction for the centrifugal fan during the a-th shutdown within the i-th sampling time period is calculated using the following formula: ； in, This represents the predicted duration of fretting wear life reduction from the a-th shutdown within the i-th sampling time period to the end of the shutdown. This represents the preset wear rate coefficient.

2. The method for assessing the lifespan of a centrifugal fan bearing according to claim 1, characterized in that, The specific implementation process of step S4 includes: Predicted duration of fretting wear life reduction from the first shutdown of the centrifugal fan during the i-th sampling time period to the end of the shutdown. Calculate the cumulative value of the predicted duration of fretting wear life reduction for the centrifugal fan during the i-th sampling time period, denoted as . ,in, A represents the total number of times the centrifugal fan stops during the i-th sampling time period; A preset threshold for the cumulative predicted duration of fretting wear life reduction is set. If the cumulative predicted duration of fretting wear life reduction for the centrifugal fan during the i-th sampling time period is... If the cumulative value of the predicted duration of fretting wear reduction is greater than or equal to the threshold value, it is determined that the centrifugal fan has an abnormal reduction in lifespan during the i-th sampling time period. In this case, an early warning is issued and relevant personnel are notified to perform shutdown maintenance.

3. A centrifugal fan bearing life assessment system, comprising performing a centrifugal fan bearing life assessment method as described in any one of claims 1-2, characterized in that, The system includes: a data acquisition module, a dust intrusion efficiency coefficient calculation module, a lifespan reduction prediction module, and a lifespan reduction cumulative value calculation, analysis, and early warning module. The data acquisition module retrieves the number of times the centrifugal fan stops during the sampling time period, the time point corresponding to each stop, and the stop duration, and simultaneously collects dust concentration data of the external and internal bearing cavities of the centrifugal fan. The dust intrusion efficiency coefficient calculation module calculates the dust intrusion efficiency coefficient of the centrifugal fan from the moment of shutdown to the moment of shutdown within a single sampling time period, based on the external dust concentration data and the internal bearing cavity dust concentration data of the centrifugal fan during a single shutdown and after the shutdown within a single sampling time period. The life reduction prediction module calculates the predicted duration of fretting wear life reduction of the centrifugal fan from a single shutdown to the end of the shutdown within a single sampling time period, based on the dust intrusion efficiency coefficient of the inner and outer cavities of the centrifugal fan. The cumulative life reduction duration calculation and analysis early warning module calculates the cumulative value of the predicted life reduction duration of the centrifugal fan within a single sampling time period based on the predicted life reduction duration of the fretting wear; presets a threshold value for the cumulative predicted duration, analyzes and issues an early warning.

4. The centrifugal fan bearing life assessment system according to claim 3, characterized in that: The dust intrusion efficiency coefficient calculation module includes a dust intrusion efficiency coefficient calculation unit; The dust intrusion efficiency coefficient calculation unit calculates the dust intrusion efficiency coefficient of the centrifugal fan from the a-th shutdown to the end of the shutdown within the i-th sampling time period, based on the external dust concentration data and internal bearing cavity dust concentration data corresponding to the a-th shutdown of the centrifugal fan within the i-th sampling time period.

5. The centrifugal fan bearing life assessment system according to claim 4, characterized in that: The life reduction duration prediction module includes a life reduction duration prediction unit; The lifespan reduction prediction unit calculates the predicted fretting wear lifespan reduction time based on the dust intrusion efficiency coefficient of the centrifugal fan from the a-th shutdown to the end of the shutdown within the i-th sampling time period. The details are as follows: A preset threshold for the dust intrusion efficiency coefficient of the inner and outer cavities is set. If the dust intrusion efficiency coefficient of the inner and outer cavities of the centrifugal fan is greater than or equal to the threshold, it is determined that the dust intrusion efficiency of the inner and outer cavities of the centrifugal fan is high from the a-th shutdown in the i-th sampling time period to the end of the shutdown. Then, the predicted duration of the fretting wear life reduction of the centrifugal fan from the a-th shutdown in the i-th sampling time period to the end of the shutdown is calculated.

6. The centrifugal fan bearing life assessment system according to claim 5, characterized in that: The cumulative lifespan reduction calculation and analysis early warning module includes a cumulative lifespan reduction calculation unit and an analysis and early warning unit; The cumulative life reduction time calculation unit calculates the cumulative value of the fretting wear life reduction prediction time of the centrifugal fan in the i-th sampling time period based on the fretting wear life reduction prediction time from the a-th shutdown to the end of the shutdown in the i-th sampling time period. The analysis and early warning unit: presets a threshold value for the cumulative predicted duration of fretting wear life reduction. If the cumulative predicted duration of fretting wear life reduction of the centrifugal fan in the i-th sampling time period is greater than or equal to the threshold value, it is determined that the centrifugal fan has an abnormal life reduction in the i-th sampling time period, and an early warning is issued and relevant personnel are notified to shut down the machine for maintenance.

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