This application is a U.S. national stage filing under 35 U.S.C. § 371 from International Application No. PCT/CN2019/118512, filed on 14 Nov. 2019, and published as WO2020/103761 on 28 May 2020, which claims the benefit under 35 U.S.C. 119 to Chinese Application No. 201811400523.X, filed on 22 Nov. 2018, the benefit of priority of each of which is claimed herein, and which applications and publication are hereby incorporated herein by reference in their entirety.
The present invention involves bearing technology, specifically, a method for determining the time to repair a bearing.
Bearing is a mechanical device widely used in various fields and industries. Failure or damage of it during the use will lead to the stoppage of production work and great repair costs.
In order to prolong the service life of the bearing, monitoring of the bearing condition during the use becomes particularly important. Conventionally, the monitoring of the bearing is achieved by the monitoring of its vibration. The core idea is: during the monitoring of the bearing vibration, when the vibration exceeds a certain threshold, it is judged that the bearing needs to be repaired. A variety of industrial standards have been proposed in the industry, with the purpose of determining the time to repair the bearing. For example, ISO IS 7919 recommends determining the time to repair the bearing by judging whether the vibration displacement of the bearing exceeds the vibration peak threshold. These industrial standards were originally used to provide general operating recommendations for the use and repair of machines and their components.
However, since the actual vibration of the bearing is affected by various environmental factors (for example, load, speed and temperature), through the existing condition monitoring mechanism, the time to repair the bearing is often inaccurate. If the time to repair the bearing is too early, the repair costs will increase; and if the time to repair the bearing is delayed, the service life of the bearing will be greatly reduced.
To address the technical issues left unsolved by the prior art, the present invention provides a method for determining the time to repair the bearing, which aims at reducing the repair cost and improving the service life of the bearing.
To address the foregoing technical issues, the present invention provides a technical scheme, wherein:
As further improvements on the foregoing technical scheme:
the NIE of the vibration signal satisfies the following formula:
therein, pk represents the possible distribution of the vibration signal; the M is a natural number;
the pk satisfies the following formula:
therein, the nk represents the number of data in each element; the N represents the number of data contained in the vibration signal; the N satisfies the following formula:
Obtaining the dimensionless criteria of the vibration signal according to the vibration signal, specifically including:
if the two distribution points are p1 and p2 respectively, the J-Divergence satisfies the following formula:
Obtaining the dimensionless criteria of the vibration signal according to the vibration signal, specifically including:
therein, the xi represents the vibration signal i; the
Obtaining the dimensionless criteria of the vibration signal according to the vibration signal, specifically including:
therein, the ΔNIE=NIEpresent−NIEreference; the ΔK=Kpresent−Kreference; the NIEpresent represents the real-time NIE value; the NIEreference represents the reference value of NIE; the Kpresent represents the real-time K value; the Kreference represents the reference value of K.
The embodiment of the present invention provides a method for determining the time to repair the bearing. Firstly, the vibration signals of the bearing under different loads are obtained, and then based on the vibration signal under each load, the dimensionless criteria are obtained separately; according to the dimensionless criteria, the damage prediction distribution data of the bearing under different loads can be obtained. Finally, based on the damage prediction distribution data under different loads, an accurate time to repair the bearing is obtained, thereby reducing the repair cost and improving the service life of the bearing.
The embodiment of the present invention provides a method for determining the time to repair the bearing. Firstly, the vibration signals of the bearing under different loads are obtained, and then based on the vibration signal under each load, the dimensionless criteria are obtained separately; according to the dimensionless criteria, the damage prediction distribution data of the bearing under different loads can be obtained. Finally, based on the damage prediction distribution data under different loads, an accurate time to repair the bearing is obtained, thereby reducing the repair cost and improving the service life of the bearing.
Optionally, the dimensionless criteria can be NIE, Kurtosis, J-Divergence and C.
Further, for the dimensionless criteria in Step 101, one possible way is:
therein, pk represents the possible distribution of the vibration signal; M is a natural number;
pk satisfies the following formula:
therein, nk represents the number of data in each element; N represents the number of data contained in the vibration signal; N satisfies the following formula:
optionally, the J-Divergence of the vibration signal can be obtained according to the vibration signal; the J-Divergence represents the pseudo distance between two possible distribution points of the vibration signal.
If the two distribution points are p1 and p2 respectively, the J-Divergence satisfies the following formula:
optionally, the Kurtosis of the vibration signal can be obtained according to the vibration signal; the Kurtosis satisfies the following formula:
therein, xi represents the vibration signal i;
Optionally, the mixed dimensionless criterion C of the vibration signal can be obtained according to the vibration signal; the mixed dimensionless criterion C satisfies the following formula:
C=√{square root over ((ΔNIE)2+(J)2+(ΔK)2)}
therein, ΔNIE=NIEpresent−NIEreference; ΔK=Kpresent−Kreference; NIEpresent represents the real-time NIE value; NIEreference represents the reference value of NIE; Kpresent represents the real-time K value; Kreference represents the reference value of K.
A final note is made as follows: the above embodiments are only used to illustrate the technical solutions of the present invention, not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, the general technicians in this field should understand: they are still allowed to modify the technical solutions illustrated in the foregoing embodiments, or equivalently replace some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of technical solutions in the embodiments of the present invention.
Number | Date | Country | Kind |
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201811400523.X | Nov 2018 | CN | national |
Filing Document | Filing Date | Country | Kind |
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PCT/CN2019/118512 | 11/14/2019 | WO |
Publishing Document | Publishing Date | Country | Kind |
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WO2020/103761 | 5/28/2020 | WO | A |
Number | Name | Date | Kind |
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20080033695 | Sahara | Feb 2008 | A1 |
20090093975 | Judd | Apr 2009 | A1 |
Number | Date | Country |
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102564759 | Jul 2012 | CN |
102831325 | Dec 2012 | CN |
102213116 | Feb 2015 | CN |
104568438 | Apr 2015 | CN |
105445004 | Mar 2016 | CN |
105975749 | Sep 2016 | CN |
109919327 | Jun 2019 | CN |
WO-2020103761 | May 2020 | WO |
Entry |
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“International Application No. PCT/CN2019/118512, International Search Report and Written Opinion dated Feb. 19, 2020”, (dated Feb. 19, 2020), 9 pgs. |
Number | Date | Country | |
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20220018733 A1 | Jan 2022 | US |