CN114894125B - Quantitative detection method for radial ball bearing raceway line - Google Patents
Quantitative detection method for radial ball bearing raceway line Download PDFInfo
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- CN114894125B CN114894125B CN202210352885.6A CN202210352885A CN114894125B CN 114894125 B CN114894125 B CN 114894125B CN 202210352885 A CN202210352885 A CN 202210352885A CN 114894125 B CN114894125 B CN 114894125B
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- measuring
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- bearing
- streamline
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- 238000001514 detection method Methods 0.000 title claims abstract description 14
- 238000009826 distribution Methods 0.000 claims abstract description 12
- 238000000034 method Methods 0.000 claims abstract description 8
- 238000005554 pickling Methods 0.000 claims abstract description 6
- 238000005520 cutting process Methods 0.000 claims abstract description 5
- 238000005498 polishing Methods 0.000 claims abstract description 5
- 238000004140 cleaning Methods 0.000 claims abstract description 3
- 229910000831 Steel Inorganic materials 0.000 claims description 8
- 239000010959 steel Substances 0.000 claims description 8
- 238000005259 measurement Methods 0.000 claims description 6
- 238000011158 quantitative evaluation Methods 0.000 abstract description 3
- 206010016256 fatigue Diseases 0.000 description 8
- 238000005406 washing Methods 0.000 description 4
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 3
- 238000011161 development Methods 0.000 description 3
- 238000005242 forging Methods 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 238000005096 rolling process Methods 0.000 description 3
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 150000001247 metal acetylides Chemical class 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 244000137852 Petrea volubilis Species 0.000 description 1
- 238000003723 Smelting Methods 0.000 description 1
- NRTOMJZYCJJWKI-UHFFFAOYSA-N Titanium nitride Chemical compound [Ti]#N NRTOMJZYCJJWKI-UHFFFAOYSA-N 0.000 description 1
- 230000006978 adaptation Effects 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 238000000861 blow drying Methods 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000000641 cold extrusion Methods 0.000 description 1
- 238000005097 cold rolling Methods 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000009749 continuous casting Methods 0.000 description 1
- 229910052593 corundum Inorganic materials 0.000 description 1
- 125000004122 cyclic group Chemical group 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 229910003460 diamond Inorganic materials 0.000 description 1
- 239000010432 diamond Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000007429 general method Methods 0.000 description 1
- 238000005098 hot rolling Methods 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 238000012827 research and development Methods 0.000 description 1
- 238000005204 segregation Methods 0.000 description 1
- 238000004901 spalling Methods 0.000 description 1
- 239000007921 spray Substances 0.000 description 1
- 239000008399 tap water Substances 0.000 description 1
- 235000020679 tap water Nutrition 0.000 description 1
- 150000003568 thioethers Chemical class 0.000 description 1
- 229910001845 yogo sapphire Inorganic materials 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/26—Measuring arrangements characterised by the use of optical techniques for measuring angles or tapers; for testing the alignment of axes
- G01B11/27—Measuring arrangements characterised by the use of optical techniques for measuring angles or tapers; for testing the alignment of axes for testing the alignment of axes
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Rolling Contact Bearings (AREA)
Abstract
The invention discloses a quantitative detection method for a radial ball bearing raceway line, which comprises the following steps: s1, cutting, embedding, polishing, hot pickling and cleaning a bearing, and then photographing; 2. the photo is imported into drawing software, the position of the center of the curvature circle of the roller path in the photo is determined, the curvature circle which coincides with the roller path is made, and after the position of the contact point is determined, the measuring range and 5 measuring positions are determined within the contact angle range; s3, measuring the included angles between the parallel lines of the streamline direction and the radius at 5 measuring positions, and subtracting 90 degrees from the included angles to obtain the accurate numerical value of the streamline distribution of the rollaway nest. The method can be used for compensating the blank of quantitative evaluation of the streamline distribution of the bearing raceway, is simple to operate and high in accuracy, and can be operated and detected by non-professional technicians.
Description
Technical Field
The invention relates to bearing detection, in particular to a quantitative detection method for a radial ball bearing raceway line.
Background
Bearing steels mainly control material purity during smelting, but deoxidized products such as Al2O3, sulfides, titanium nitride and low-melting point compounds remain in the steel, and mainly control material uniformity during continuous casting, but still have segregation problems and form banded carbides. In the subsequent rolling process of the bearing steel, the residues and the band-shaped carbides are distributed along the rolling direction to form streamline along with the increase of the rolling ratio.
The streamline can influence the mechanical property of the structural member, and the streamline is distributed along the appearance of the part, so that the strength of the part can be improved. For bearings, the flow lines mainly affect the fatigue performance of the bearing, for example, if the two poles of the steel ball and the annular band are areas where the flow lines are cut off, fatigue spalling often occurs here. The raceway positions of the bearing are subjected to cyclic contact stress during operation, and fatigue stripping can also occur due to streamline distribution. At present, the technological processes influencing the streamline distribution of the bearing products are quite many, such as steel pipe straight turning, sleeve forging, single forging, cold extrusion, hot rolling and cold rolling, even upsetting height in the forging process and die design, so the streamline distribution condition of the bearing products is quite different. The included angle between the streamline and the tangent line of the contact point of the rollaway nest represents the parallelism degree of the streamline and the rollaway nest, the smaller the included angle is, the more parallel the streamline and the rollaway nest tend to be, the better the fatigue life of the bearing is, and the larger the included angle between the streamline at the rollaway nest and the tangent line of the contact point of the rollaway nest is, the worse the fatigue performance is.
The deep groove ball bearing in the radial ball bearings is the bearing with the largest use amount at present, but a simple and general method for quantitatively describing the streamline distribution condition does not exist at present.
Disclosure of Invention
Aiming at the defects existing in the prior art, the invention aims to provide the quantitative detection method for the radial ball bearing raceway line, which can be used for compensating the blank of quantitative evaluation of the streamline distribution of the bearing raceway, is simple to operate and high in accuracy, and can be operated for detection by even non-professional technicians.
In order to achieve the above purpose, the present invention provides the following technical solutions:
a quantitative detection method for a radial ball bearing raceway line comprises the following steps:
s1, cutting, embedding, polishing, hot pickling and cleaning a bearing, and then photographing;
s2, importing the photo into drawing software, determining the position of the circle center of curvature of the roller path in the photo, making a curvature circle coincident with the roller path, determining the position of a contact point, and determining a measuring range and 5 measuring positions within the contact angle range;
s3, measuring the included angles between the parallel lines of the streamline direction and the radius at 5 measuring positions, and subtracting 90 degrees from the included angles to obtain the accurate numerical value of the streamline distribution of the rollaway nest.
Based on the flow, the method is convenient to operate, can be operated by non-professional technicians, has wider applicability, can relieve the professional technicians in the quality inspection process, and improves the research and development efficiency of enterprises. Meanwhile, the gap of quantitative evaluation of the streamline distribution of the bearing raceway can be made up, the accuracy is high, and the high accuracy can be maintained even if the bearing raceway is operated by non-professional technicians.
As a further improvement of the present invention, wherein the drawing software employs CAD software. CAD software is convenient to operate, and extensive applicability to from taking the point location to catch and the angle is caught and can be operated the location fast, but detection efficiency is higher, and it is fast to non-professional technical personnel, the misoperation rate is low.
As a further development of the invention, the optimal centre of curvature and the position of the curvature circle are determined by means of a mapping software. The multipoint circle drawing or multipoint arc drawing function of CAD software can be utilized to automatically calculate and obtain the arc of the roller path in the attached photo.
As a further development of the invention, the contact angle is determined according to the bearing type, which contact angle is in the range of 0-45 °. The different contact angles are determined according to the type of bearing, the contact angles determine the measuring range, and the different contact angles are selected according to the different measuring ranges required by different bearings.
As a further development of the invention, the measurement range in step S2 is determined according to the following steps: determining the curvature circle center position O of the raceway, the contact point position A of the steel ball and the raceway, connecting OA to be an arc coincident with the raceway, and taking OA as a boundary + -alpha range, wherein alpha is a contact angle of 0-45 degrees, namely +.AOE=alpha and +.AOD=alpha; the arc DE is the measurement range. The operation steps are simple, the operation can be performed quickly through CAD software, and the operation can be performed simply for non-professional technicians.
As a further improvement of the invention, the 5 measuring points in step S2 are determined according to the following steps: bisecting the angle AOE to obtain an intersection point C on the circular arc, bisecting the angle AOD to obtain an intersection point B on the circular arc, and obtaining 5 measuring positions in a measuring range by points E, C, A, B and D. The 5 measurement positions obtained through the scheme are more uniform, and the detection effect can be more accurate.
Drawings
FIG. 1 is a schematic diagram of the dotting result of the present invention;
FIG. 2 is a graph showing the detection results (unmodified) of the embodiment of the present invention;
FIG. 3 is a schematic diagram of the detection results (improved) of the embodiment of the present invention.
Detailed Description
The invention will be further described in detail with reference to examples of embodiments shown in the drawings.
As shown with reference to figures 1-3,
a quantitative detection method for a radial ball bearing raceway line comprises the following steps:
(1) The bearing is cut along the cross section to be about 5mm wide, hot mosaic materials with the particle size smaller than 0.2mm are used for mosaic, 100-mesh, 400-mesh, 1200-mesh and 2000-mesh aluminum oxide waterproof sand paper are respectively used for grinding samples, diamond spray polishing agents are used for polishing, hydrochloric acid aqueous solution (1:1) is used for hot pickling, the temperature is 70-80 ℃, and the temperature is kept for 15-30 min. Washing with tap water, washing with alcohol, blow-drying, making streamline clearly visible, photographing, and storing.
(2) The photo is imported into professional drawing software CAD, the circle center position O of the curvature of the rollaway nest and the contact point position A of the steel ball and the rollaway nest are determined through calculation and conversion according to the relevant size of the bearing drawing, the connection OA is an arc overlapped with the rollaway nest, the OA is used as a boundary + -alpha range, alpha is a contact angle of about 0-45 degrees, namely ++AOE=alpha and ++AOD=alpha. The arc DE is the measurement range.
(3) Bisecting the angle AOE to obtain a point C, bisecting the angle AOD to obtain a point B, and obtaining 5 measuring positions in a measuring range by the points E, C, A, B and D. Reference is made to figure 1.
(4) And 5 short lines are respectively drawn at 5 measuring positions along the streamline direction, and the included angles of the 5 short lines and the radius are respectively measured, so that the angle E-90 degrees, the angle C-90 degrees, the angle A-90 degrees, the angle B-90 degrees and the angle D-90 degrees are included angles of tangent lines of contact points of the streamline and the rollaway nest.
The angle after calculation can be used to reflect whether there is a risk of fatigue flaking in the respective region.
The following examples illustrate:
as shown in reference to figure 2 of the drawings,
(1) Cutting and embedding an inner ring of a 6201-type deep groove ball bearing, carrying out hot pickling, and photographing after washing with water and alcohol.
(2) Introducing CAD drawing, determining circle center O, measuring range arc DE, measuring position points E, C, A, B, D
(3) At the measuring position points E, C, A, B, D, the line is drawn along the streamline direction, and the included angle between the line and the radius is measured
(4) The streamline distribution condition at the bearing raceway is obtained as follows:
∠E-90°＝128°-90°＝38°
∠C-90°＝119°-90°＝29°
∠A-90°＝98°-90°＝8°
∠B-90°＝97°-90°＝7°
∠D-90°＝105°-90°＝15°
the included angle between the CE area streamline and the contact point tangent line of the rollaway nest is larger, and compared with other measuring range areas, the CE area streamline and the rollaway nest contact point tangent line have higher fatigue peeling risks.
As shown in reference to figure 3 of the drawings,
(1) Cutting and embedding an inner ring of the 6201-model deep groove ball bearing after certain improvement, carrying out hot pickling, and photographing after washing by using water and alcohol.
(2) Introducing CAD drawing, determining circle center O ', measuring arc line D' E ', measuring position points E', C ', A', B ', D'
(3) At the measuring position points E ', C ', A ', B ', D ' the line is drawn along the streamline direction, and the included angle between the line and the radius is measured
(4) The streamline distribution condition at the bearing raceway is obtained as follows:
∠E’-90°＝105°-90°＝15°
∠C’-90°＝96°-90°＝6°
∠A’-90°＝99°-90°＝9°
∠B’-90°＝96°-90°＝6°
∠D’-90°＝109°-90°＝19°
the included angle between the streamline at the improved rear rollaway nest and the rollaway nest contact point is smaller, and the influence on the fatigue life of the bearing is smaller.
The above description is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above examples, and all technical solutions belonging to the concept of the present invention belong to the protection scope of the present invention. It should be noted that modifications and adaptations to the present invention may occur to one skilled in the art without departing from the principles of the present invention and are intended to be within the scope of the present invention.
Claims (4)
1. The quantitative detection method for the radial ball bearing raceway line is characterized by comprising the following steps of:
s1, cutting, embedding, polishing, hot pickling and cleaning a bearing, and then photographing;
s2, importing the photo into drawing software, determining the position of the circle center of curvature of the roller path in the photo, making a curvature circle coincident with the roller path, determining the position of a contact point, and determining a measuring range and 5 measuring positions within the contact angle range;
s3, measuring included angles between parallel lines of the streamline direction and the radius at 5 measuring positions, and subtracting 90 degrees from the included angles to obtain accurate values of streamline distribution of the rollaway nest;
the measurement range in step S2 is determined according to the following steps:
determining the curvature circle center position O of the raceway and the contact point position A of the steel ball and the raceway, connecting OA to be an arc coincident with the raceway, and taking OA as a boundary + -alpha range, wherein alpha is a contact angle of 0-45 degrees, namely +.AOE=alpha and +.AOD=alpha; the arc DE is the measuring range;
the 5 measurement points in step S2 are determined according to the following steps:
bisecting the angle AOE to obtain an intersection point C on the circular arc, bisecting the angle AOD to obtain an intersection point B on the circular arc, and obtaining 5 measuring positions in a measuring range by points E, C, A, B and D.
2. The method of claim 1, wherein the mapping software is CAD software.
3. The method of claim 1, wherein the optimal center of curvature and location of the circle of curvature are determined by mapping software.
4. A method according to claim 3, characterized in that the contact angle is in the range of 0-45 ° depending on the kind of bearing.
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