CN-121994468-A - Method and system for monitoring health state of slewing bearing

CN121994468ACN 121994468 ACN121994468 ACN 121994468ACN-121994468-A

Abstract

The application discloses a method and a system for monitoring the health state of a slewing bearing, wherein the method comprises the steps of obtaining an axial displacement amplitude and a radial displacement amplitude of an outer ring of the slewing bearing relative to an inner ring, determining an axial displacement amplitude difference and a radial displacement amplitude difference in unit time, judging that bolts of the slewing bearing are loosened if the axial/radial displacement amplitude periodically changes in a step or suddenly changes, and judging that the axial displacement amplitude reaches an axial clearance limit value and the axial displacement amplitude difference continuously increases, the radial displacement amplitude reaches a radial clearance limit value and the radial displacement amplitude difference continuously increases, judging that the axial/radial displacement amplitude difference in unit time is more than 3 times of the axial/radial displacement amplitude difference in the previous unit time, judging that the raceway is excessively worn, and carrying out two-dimensional cross-validation, so that fault identification accuracy is improved, and raceway wear and bolt loosening are accurately distinguished.

Inventors

HOU WENFENG
HAN DONGYA
GU XIANG
YAN XUEYUAN
ZHANG LIWEI
FENG XU

Assignees

徐州徐工挖掘机械有限公司

Dates

Publication Date: 20260508
Application Date: 20260202

Claims (10)

1. The slewing bearing health state monitoring system is characterized by comprising a controller, a first non-contact displacement sensor and a second non-contact displacement sensor; The first non-contact displacement sensor is used for detecting the axial displacement amplitude of the outer ring of the slewing bearing relative to the inner ring and uploading the axial displacement amplitude to the controller; The second non-contact displacement sensor is used for detecting the radial displacement amplitude of the outer ring of the slewing bearing relative to the inner ring and uploading the radial displacement amplitude to the controller; the controller is respectively connected with the first non-contact displacement sensor and the second non-contact displacement sensor in a signal way.
2. The slewing bearing health status monitoring system as set forth in claim 1 wherein, The first non-contact displacement sensor is screwed into an axial displacement sensor mounting hole in the axial displacement sensor mounting seat, the axial displacement sensor mounting seat is screwed into an axial displacement sensor mounting seat mounting hole in the turntable bottom plate, and the first non-contact displacement sensor faces the slewing bearing inner ring along the axial direction; The second non-contact displacement sensor is screwed into a radial displacement sensor mounting hole in the radial displacement sensor mounting seat, the radial displacement sensor mounting seat is screwed into a radial displacement sensor mounting seat mounting hole in the turntable bottom plate, and the second non-contact displacement sensor faces the inner wall of the butter pool in the radial direction, and the inner wall of the butter pool is static relative to the slewing bearing inner ring; wherein, the revolving stage bottom plate is fixed on the slewing bearing outer race relatively.
3. The slewing bearing health status monitoring system of claim 1 wherein an axial displacement sensor mount via hole in communication with the axial displacement sensor mount hole is formed in the axial displacement sensor mount for a signal line and a power line of the first non-contact displacement sensor to pass through; The radial displacement sensor mounting seat is provided with a radial displacement sensor mounting seat wire passing hole communicated with the radial displacement sensor mounting hole, and a signal wire and a power wire of the second non-contact displacement sensor pass through the radial displacement sensor mounting seat wire passing hole.
4. The slewing bearing health status monitoring system of claim 1 wherein an axial displacement sensor mount screw thread is provided on the outer periphery of the axial displacement sensor mount for threaded connection with the turntable base plate; the periphery of the radial displacement sensor mounting seat is provided with radial displacement sensor mounting seat threads which are used for being in threaded connection with the turntable bottom plate; And/or the axial displacement sensor mounting seat is fixed in the turntable bottom plate by screwing the first locking nut, and the radial displacement sensor mounting seat is fixed in the turntable bottom plate by screwing the second locking nut.
5. A slewing bearing health status monitoring method, characterized in that based on the slewing bearing health status monitoring system as defined in any one of claims 1 to 4, the method comprises: acquiring an axial displacement amplitude A and a radial displacement amplitude B of an outer ring of the target slewing bearing relative to an inner ring in real time; according to the axial displacement amplitude A and the radial displacement amplitude B in unit time, determining an axial displacement amplitude difference delta A and a radial displacement amplitude difference delta B in unit time; Extracting axial displacement waveform characteristics and radial displacement waveform characteristics according to the axial displacement amplitude A and the radial displacement amplitude B which are continuous for a period of time; If the axial displacement amplitude A or the radial displacement amplitude B periodically changes in a step mode or suddenly changes, judging that the slewing bearing is loosened, wherein the axial displacement amplitude A periodically changes in a step mode, namely that an axial displacement amplitude difference delta A appears at the same time of a plurality of continuous periods and is larger than an axial displacement amplitude difference of a later unit time and an axial displacement amplitude difference of a former unit time, and the radial displacement amplitude B periodically changes in a step mode, namely that a radial displacement amplitude difference delta B appears at the same time of a plurality of continuous periods and is larger than a radial displacement amplitude difference of a later unit time and a radial displacement amplitude difference of a former unit time; The abrupt change of the axial displacement amplitude A indicates that the axial displacement amplitude A at a certain time is larger than or equal to the corresponding axial gap limit value Amax and the axial displacement amplitude difference is larger than the axial displacement amplitude difference at a later unit time and the axial displacement amplitude difference at a former unit time in the normal abrasion stage, and the abrupt change of the radial displacement amplitude B indicates that the radial displacement amplitude B at a certain time is larger than or equal to the corresponding radial gap limit value Bmax and the radial displacement amplitude difference is larger than the radial displacement amplitude difference at a later unit time and the radial displacement amplitude difference at a former unit time in the normal abrasion stage.
6. The method of claim 5, further comprising, after determining the axial displacement amplitude difference Δa and the radial displacement amplitude difference Δb per unit time: If at least one of (a) the axial displacement amplitude A reaches the axial gap limit value Amax, the axial displacement amplitude difference value delta A is continuously increased, (B) the radial displacement amplitude B reaches the radial gap limit value Bmax, the radial displacement amplitude difference value delta B is continuously increased, (c) the axial displacement amplitude difference value delta A is continuously increased and is more than 3 times of the axial displacement amplitude difference value in the previous unit time, (d) the radial displacement amplitude difference value delta B is continuously increased and is more than 3 times of the radial displacement amplitude difference value in the previous unit time, and the raceway is judged to be excessively worn.
7. The method of claim 6, further comprising alerting the slewing bearing to excessive raceway wear and alerting the slewing bearing to replacement after determining excessive raceway wear.
8. The method for monitoring health of a slewing bearing according to claim 5, further comprising performing a bolt loosening alarm after judging that the slewing bearing is loosened.
9. The slewing bearing health status monitoring system of claim 1 wherein the controller comprises a processor and a storage medium; The storage medium is used for storing instructions; the processor is operative according to the instructions to perform the slewing bearing health status monitoring method as set forth in any one of claims 5-8.
10. A construction machine, characterized in that the slewing bearing health status monitoring system according to any one of claims 1 to 4 or 9 is provided.

Description

Method and system for monitoring health state of slewing bearing Technical Field The application belongs to the technical field of slewing bearing fault monitoring, relates to a slewing bearing health state monitoring method and system, and in particular relates to a slewing bearing health state monitoring method and system based on gap monitoring. Background Raceway wear and bolt looseness of slewing bearings are high-level failures of the excavator. The prior art realizes the monitoring of the health state of the slewing bearing by collecting and analyzing signals such as noise, vibration and the like or periodically dismantling or testing the content of grease and scrap iron of the slewing bearing, and the monitoring result is more easily influenced by the operation vibration of the excavator and dust and foreign matters in the external environment. The traditional detection method has the defects of low efficiency, easy operation interference of the existing noise and vibration monitoring method and incapability of distinguishing the damage of the rollaway nest and the loosening of the bolt. Disclosure of Invention In view of at least one of the technical problems, the application provides a slewing bearing health state monitoring method and system, which improve fault identification accuracy by monitoring axial and radial displacement changes of an outer ring relative to an inner ring and performing two-dimensional cross validation. The technical scheme adopted by the application is as follows: In a first aspect, a slewing bearing health status monitoring system is provided, comprising a controller, a first non-contact displacement sensor and a second non-contact displacement sensor; The first non-contact displacement sensor is used for detecting the axial displacement amplitude of the outer ring of the slewing bearing relative to the inner ring and uploading the axial displacement amplitude to the controller; The second non-contact displacement sensor is used for detecting the radial displacement amplitude of the outer ring of the slewing bearing relative to the inner ring and uploading the radial displacement amplitude to the controller; the controller is respectively connected with the first non-contact displacement sensor and the second non-contact displacement sensor in a signal way. In some embodiments, the first non-contact displacement sensor is threaded into an axial displacement sensor mount hole in an axial displacement sensor mount, the axial displacement sensor mount is threaded into an axial displacement sensor mount hole in the turntable base plate, and the first non-contact displacement sensor is axially directed toward the slewing bearing inner race; The second non-contact displacement sensor is screwed into a radial displacement sensor mounting hole in the radial displacement sensor mounting seat, the radial displacement sensor mounting seat is screwed into a radial displacement sensor mounting seat mounting hole in the turntable bottom plate, and the second non-contact displacement sensor faces the inner wall of the butter pool in the radial direction, and the inner wall of the butter pool is static relative to the slewing bearing inner ring; wherein, the revolving stage bottom plate is fixed on the slewing bearing outer race relatively. In some embodiments, an axial displacement sensor mounting seat is provided with an axial displacement sensor mounting seat wire passing hole communicated with the axial displacement sensor mounting hole, and a signal wire and a power wire of the first non-contact displacement sensor pass through the axial displacement sensor mounting seat wire passing hole; The radial displacement sensor mounting seat is provided with a radial displacement sensor mounting seat wire passing hole communicated with the radial displacement sensor mounting hole, and a signal wire and a power wire of the second non-contact displacement sensor pass through the radial displacement sensor mounting seat wire passing hole. In some embodiments, the axial displacement sensor mount is provided with axial displacement sensor mount threads on the periphery for threaded connection with the turntable floor; the periphery of the radial displacement sensor mounting seat is provided with radial displacement sensor mounting seat threads which are used for being in threaded connection with the turntable bottom plate; in some embodiments, the axial displacement sensor mount is secured in the turntable floor by tightening a first lock nut and the radial displacement sensor mount is secured in the turntable floor by tightening a second lock nut. In a second aspect, a method for monitoring health status of a slewing bearing is provided, based on the slewing bearing health status monitoring system, the method includes: acquiring an axial displacement amplitude A and a radial displacement amplitude B of an outer ring of the target slewing bearing relative to an inner ring in real time; accordin