Dye penetrant testing method for non-destructive testing of a bearing component and testing device

Abstract

A dye penetrant method for the non-destructive testing of a bearing component, in particular a rolling bearing component, is disclosed, comprising the steps (a) irradiating the rolling bearing component provided with a fluorescent dye with excitation photons, so that fluorescence photons are generated, and (b) detecting fluorescence photons.

Description

[0001] The invention relates to a dye penetration method for the non-destructive testing of a bearing component, in particular a rolling bearing component, in particular a rolling element of a rolling bearing, comprising the steps of (a) irradiating the rolling bearing component provided with a fluorescent dye with excitation photons so that fluorescence photons are generated, and (b) detecting fluorescence photons.

[0002] According to a second aspect, the invention relates to a testing device for the non-destructive testing of rolling bearing components, in particular for surface or edge zone defects, comprising (a) a holder for receiving the rolling bearing component, (b) a light source, in particular a laser, for irradiating the rolling bearing component with excitation photons and a detector, in particular a camera, for detecting fluorescence photons emitted by the rolling bearing component due to the irradiation.

[0003] The dye penetrant method is used in the non-destructive testing of rolling bearing components, especially rolling elements, to check for surface defects. Surface defects include cracks, especially microcracks, and defects such as cavities, pores, or indentations. A fluorescent dye is applied to the rolling bearing component and partially removed if necessary, so that the fluorescent dye remains only in areas that are difficult to access for cleaning. These are usually surface defects.

[0004] The higher the demands placed on the rolling bearing component, the smaller the surface defects that must be detected. It has been found that very fine cracks cannot be reliably detected using the conventional dye penetrant method.

[0005] The invention is based on the object of reducing disadvantages in the prior art.

[0006] The invention solves the problem by a generic dye penetration method with the steps of detecting the respective delay time of the fluorescence photons between the emission of the excitation photon triggering the fluorescence photon, in particular the excitation photons, onto the rolling bearing component on the one hand and the detection of the fluorescence photon on the other hand and determining surface defects of the rolling bearing component based on the delay times.

[0007] The invention further solves the problem by a generic testing device having an evaluation unit configured to automatically carry out a method comprising the steps of (i) detecting the respective delay time of the fluorescence photons between the emission of the excitation photons onto the rolling bearing component and the detection of the fluorescence photon, and (ii) displaying an image of the rolling bearing component based on the delay times and / or calculating at least one error parameter encoding an extent of surface defects of the rolling bearing component from the delay times.

[0008] According to the invention, the use of a fluorescence lifetime microscope for non-destructive testing for cracks and / or surface or edge zone defects in components is also provided.

[0009] The invention also relates to a rolling bearing manufacturing device for manufacturing a rolling bearing from at least two rolling bearing components, comprising (a) a system for manufacturing at least a first rolling bearing component and (b) a testing device according to the invention, which is arranged and designed for testing, in particular automatically, this rolling bearing component. The rolling bearing manufacturing device preferably comprises an assembly system for assembling the rolling bearing using the tested rolling bearing component, wherein preferably only rolling bearing components found to be free of defects are used.

[0010] An advantage of the invention is that the detection of surface defects can generally be performed more quickly than with conventional dye penetrant methods. The reason for this is that by detecting surface defects based on the delay times, interfering signals, such as those from reflected photons or photons generated by scattering, can be suppressed, since their delay times differ from those of the fluorescence photons. This makes it possible to eliminate background signals.

[0011] Another advantage is that surface defects can be detected with comparatively high reliability. This is because photons emitted by the rolling bearing component that are not fluorescence photons can be discriminated. Detecting the surface defect therefore depends significantly less on the preparation of the rolling bearing component.

[0012] In other words, the invention can sufficiently suppress background effects and effects caused by impurities in the rolling bearing component so that the actual signal caused by surface defects is detected with a higher contrast.

[0013] In the context of this description, a surface defect is understood to mean, in particular, a crack, for example, a microcrack. A microcrack is understood to mean, in particular, a crack whose extent in both spatial directions along the surface of the rolling bearing component is less than 0.5 mm, in particular less than 0.25 mm.

[0014] A bearing component is understood to mean, in particular, any component used in a bearing. The bearing can be a plain bearing, a magnetic bearing, or a rolling bearing. Whenever reference is made to a rolling bearing or rolling bearing component in the following, this always also generally refers to a bearing or bearing component and a plain bearing or plain bearing component.

[0015] A rolling bearing component is understood to mean in particular any component that is used in a rolling bearing.

[0016] The peripheral zone refers specifically to the area of ​​the rolling bearing component that extends from the surface to the depth that is altered by machining, particularly by cutting. The mechanical stress on the rolling bearing component is generally limited to the peripheral zone.

[0017] A fluorescent dye is understood, in particular, to be a substance that exhibits spontaneous light emission shortly after excitation with light. Preferably, the spontaneous emission of light, i.e., fluorescence, decays exponentially. The corresponding half-life, also called the fluorescence lifetime or decay constant, is preferably at least τ = 1 ns.

[0018] Capturing fluorescence photons is understood to mean detecting. In other words, the impact of a fluorescence photon on a corresponding detector produces a signal, particularly an electrical one, which is recorded.

[0019] Detecting the delay time is understood, in particular, as a process that allows the delay time to be inferred. Thus, it is possible for the delay time to include the time of flight of the excitation photons and the fluorescence photons. It is also possible for the delay time to be determined modulo an intensity variation time with which the excitation light from the excitation photons is modulated according to one embodiment.

[0020] Detecting surface defects refers to any process that allows the differentiation of defective areas of a rolling bearing component from non-defective areas. The defect parameter can be, for example, a number, a vector, or an image. It is possible, but not necessary, for the defect parameter to encode the location where the defect occurred. It is sufficient for the defect parameter to encode that a surface defect was detected at some point within a measurement area on the rolling bearing component.

[0021] A receptacle is understood in particular to mean a device by means of which the rolling bearing component can be brought into a predetermined position relative to the light source and / or the detector.

[0022] Preferably, the dye penetrant test is carried out according to ASTM E 1417 or ISO 3452-2.

[0023] It is advantageous if the mount is designed to rotate the rolling bearing component. Particularly preferably, the mount is designed to automatically rotate the rolling bearing component along at least two axes that are not parallel to each other.

[0024] It is advantageous if the rolling bearing component is a rolling element. For example, the rolling element is made of ceramic. Cracks, even microcracks, can lead to the rolling element breaking. Therefore, it is beneficial for the operational reliability of the rolling bearing if even microcracks can be reliably detected. The rolling element can be a sphere, a cylinder, or a truncated cone, for example. However, the rolling bearing component can also be made of metal, especially steel, and / or plastic.

[0025] The excitation photons can have a wavelength in the visible range, the UV range or the infrared range.

[0026] It is advantageous if the delay time of the fluorescence photons is recorded spatially resolved. This means that for each detected fluorescence photon, in addition to the delay time, the location on the rolling bearing component from which the fluorescence photon was emitted is determined.

[0027] Preferably, sensitivity levels according to ISO 3452-1 and 3452-2 and / or EN 571 are three or four. This enables efficient penetration into cracks.

[0028] Irradiation can be point-based, linear, or area-based. Fluorescence photons can also be captured point-based, linear, or area-based. In particular, the fluorescence photons can be captured using a line-scan camera or an area-scan camera. This can reduce measurement time with the appropriate setup. For example, the detector can be a point, line, or area detector.

[0029] Preferably, the method according to the invention is carried out automatically.

[0030] According to a preferred embodiment, the method comprises step (a) applying the fluorescent dye to the rolling bearing component. Preferably, the method comprises step (b) removing a portion of the fluorescent dye after applying the fluorescent dye and before irradiating with excitation photons and detecting the delay time. The removal of fluorescent dye is preferably carried out in accordance with ISO 3452-1 and 3452-2 and / or EN 571. In particular, the removal of fluorescent dye is carried out such that, in areas with surface defects, at most one-fifth, in particular at most one-tenth, of the fluorescent dye is removed per area as in areas without surface defects. As is usual with dye penetration processes, this serves to reduce background radiation.

[0031] Removal may, for example, be carried out by abrasion, wiping, blowing, or rubbing. Preferably, removal is carried out in such a way that fluorescent dye is substantially completely removed from areas of the surface without surface defects.

[0032] Preferably, the determination of surface defects based on the delay times comprises the step of successively recording the delay times of the fluorescence photons for all points of a measurement area on the surface of the rolling bearing component. It is advantageous if the determination of surface defects based on the delay times includes the step of issuing a warning message when a surface defect has been detected. The warning message is issued, for example, when a defect parameter encoding the extent of a surface defect exceeds a predetermined threshold.

[0033] The warning message can be perceptible by humans and / or machines. For example, the warning message is an optical or electrical signal. The warning message encodes the information that a surface defect has been found. It is possible, but not necessary, for the warning message to encode the location where the surface defect was found. In particular, it is possible for the warning message to merely encode the information that a surface defect has been detected at some point on the measuring range. If the method is carried out automatically, as provided according to a preferred embodiment, the warning message can, for example, lead to the rejection of the rolling bearing component.

[0034] Alternatively or additionally, determining surface defects of the rolling bearing component based on the delay times comprises the step (a) spatially resolved detection of the delay times of the fluorescence photons, so that a delay-time-dependent number of fluorescence photons is obtained. According to one embodiment, determining surface defects of the test object based on the delay times comprises the step (b) displaying in an image only those fluorescence photons whose delay times lie within a predetermined acceptance interval. The image preferably encodes the number or wavelength of the detected fluorescence photons. For example, the spatially resolved detection of the delay times is carried out using single-photon measurement. The acceptance interval is selected in particular such that photons originating from reflections or scattering processes are discriminated against.In this way, a user or an image analysis system, such as artificial intelligence, can detect surface defects with high accuracy.

[0035] Alternatively or additionally, the detection of surface defects comprises the step (a) spatially resolved detection of the delay times of the fluorescence photons, thereby obtaining a delay-time-dependent fluorescence photon count, and / or the step (b) displaying an image showing a ratio of the fluorescence photon counts of two different delay times and / or different spectral ranges. In this way, a high contrast is created between areas with surface defects and areas without surface defects.

[0036] Again alternatively or additionally, the determination of surface defects is carried out by (a) adjusting the delay-time-dependent number of fluorescence photons with (i) a first decay function f1, which describes the dependence of the fluorescence photons emitted per unit of time as a function of a first decay constant τ1 and a first, in particular spatially resolved, prefactor n 0,1 and (ii) at least one second decay function which describes the dependence of the fluorescence photons emitted per unit of time on a second decay constant τ2, which differs from the first decay constant, and a second, in particular spatially resolved, prefactor n 0,2 and preferably (b) determining the surface defect, in particular only, from one of the spatially resolved prefactors and / or displaying the spatially resolved prefactors in an image.

[0037] Fitting with decay functions is more computationally intensive, but provides high contrast between areas with and without surface defects, especially with a low number of detected fluorescence photons. It is possible to use three, four, or more decay functions. Fitting could also be referred to as "fitting." The prefactor is the factor in front of the exponential function. This number could also be called the amplitude, even if the exponential function does not have a complex-valued exponent.

[0038] For the first decay function f1, in particular, f1(t) = n 0,1 *exp(-τ1t) + a1. For the second decay function f2, in particular, f2(t) = n 0,2 *exp(-τ2t) + a2.

[0039] Preferably, the number of fluorescence photons is determined spatially resolved and optionally displayed in the image. The feature that the number of fluorescence photons is determined spatially resolved is understood in particular to mean that the number of fluorescence photons is determined as a function of the position on the rolling bearing component from which the corresponding fluorescence photon was emitted.

[0040] Alternatively, surface defects are determined by calculating the spatially resolved first moment of the spatially resolved delay-time-dependent fluorescence photon count and determining the surface defect, in particular only, from the spatially resolved moment. This calculation is such that a shorter evaluation time is achieved.

[0041] To further increase the evaluation accuracy, it is advantageous to deconvolve the delay-time-dependent fluorescence photon count with a transfer function of a test device used to detect the delay-time-dependent fluorescence photon count before determining the delay times. Deconvolution is understood to mean performing the inverse function of the mathematical convolution.

[0042] The acceptance interval preferably has a lower limit in the form of a minimum delay time. The minimum delay time is greater than the time of flight of photons reflected or scattered by the rolling bearing component. The scattering can be, for example, Raman scattering.

[0043] Particularly preferably, the minimum delay time is greater than the decay time of fluorescent radiation from the material of which the rolling bearing component is made and / or from dirt adhering to the rolling bearing component. In this way, corresponding measurement results can be eliminated, which advantageously increases the contrast.

[0044] The method preferably comprises the step of discriminating and / or filtering out measurement events of photons whose wavelength lies outside a predetermined target wavelength interval. This reduces background radiation and radiation due to reflections. Fluorescence photons have lower energy and thus a longer wavelength than the excitation photons. The target wavelength interval is preferably selected such that excitation photons are not included. Discrimination is understood as ensuring that corresponding photons are not included in the error parameter or are included only to a negligibly small extent. In this way, only selected fluorescence photons are detected. Instead of selected fluorescence photons, one could also speak of frequency-selected fluorescence photons.

[0045] The selected fluorescence photons can be evaluated and / or displayed as described above.

[0046] The rolling bearing component can be irradiated with excitation photons using a pulsed light source, in particular a pulsed laser. Alternatively or additionally, the irradiation can be performed using an intensity-modulated light source, in particular an intensity-modulated laser. The light source can also be a diode or a flash lamp. The pulsed laser is, for example, a picosecond laser. The half-width of a picosecond laser is preferably at most 1000 ps, ​​preferably at most 100 ps, ​​particularly preferably at most 50 ps.

[0047] The error parameter can also be an area measure that indicates the size of regions in which the area-specific emission density of, in particular, selected, fluorescence photons is above a given fluorescence threshold. In other words, this area measure measures the size of the regions from which many non-discriminated, in particular selected, photons were emitted.

[0048] The error parameter can also be a maximum value of the emission density of, in particular, selected, fluorescence photons. In particular, the error parameter can also be a, in particular weighted, average of several individual error parameters or a vector with several error parameters.

[0049] Preferably, the testing device has an application device for automatically applying a fluorescent dye to the rolling bearing component. This eliminates manual preparation.

[0050] The inspection device may include a removal device for automatically removing a portion of the fluorescent dye. This removal device removes the fluorescent dye, at least predominantly, only in areas where no surface defect is present.

[0051] The camera is preferably a time-slot camera and / or a time-of-flight camera. Time-slot cameras are also known as gated cameras, while time-of-flight cameras are also known as time-of-flight cameras.

[0052] It is possible to irradiate the rolling bearing component in flight (of the rolling bearing component) or while sinking in a liquid and to capture the fluorescence photons using the detector.

[0053] It is also possible for the rolling bearing component to be placed in a liquid during irradiation with excitation photons and / or during detection of fluorescence photons. For example, the liquid is a mineral oil product, particularly kerosene.

[0054] The invention also relates to a bearing component that has been tested using a method according to the invention and to which a test certificate is assigned, in which the test result is confirmed. In particular, the entirety of the bearing component tested in this way and the test certificate is also according to the invention. Also according to the invention is a bearing, in particular a rolling bearing, that contains the bearing component and to which the test certificate is assigned.

[0055] The invention is explained in more detail below with reference to the accompanying drawings. Fig. 1 a schematic view of a test device according to the invention for carrying out a method according to the invention, Fig. 2a a histogram of a first measurement plotting the number of received fluorescence photons against the respective delay time, Fig. 2b a histogram of a second measurement, which plots the number of received fluorescence photons against the respective delay time, Fig. 2c a first image of a bearing component in the form of a rolling element, in which image all received fluorescence photons are plotted, Fig. 2d a second image that differs from the first image in that photons that have a minimum delay time of, for example, t min =11 ns, were discriminated against, Fig. 2e a schematic representation of Fig. 2c Fig. 2f a schematic representation of Fig. 2d and Fig. 3 a rolling bearing manufacturing device according to the invention

[0056] Fig. Figure 1 shows a testing device 10 for the non-destructive testing of a component in the form of a bearing component, in this case a rolling bearing component 12. Here, the bearing component is a rolling element 14 being tested for surface or edge zone defects. The testing device 10 has a holder 16 for holding the rolling bearing component 12 and a light source 18 for irradiating the rolling bearing component 12 with excitation photons 20.i (i = 1, 2, ...), which form excitation light 22.

[0057] The test device 10 also has a detector 24, in particular in the form of a single-photon detector 26, for detecting fluorescence photons 28.j (j = 1, 2, ...) that are reflected by a fluorescent dye 30 contained in a surface defect 32. The surface defect 32 is, for example, as shown in Fig. 1 schematically drawn around a crack 33. The detector 24 is connected to an evaluation unit 34, which may have a screen 36, but this is not necessary.

[0058] The receptacle 16 can be designed to automatically rotate the rolling bearing component 12, for example about a vertical axis V and / or a horizontal axis H.

[0059] The detector 24 may be, as in Fig. 1, a detector can be used that detects the fluorescence photons 28.j only from a point of impact A on the rolling bearing component 12. However, it is also conceivable that the detector 24 comprises or is formed by a camera or a detector array.

[0060] To carry out a dye penetration process according to the invention, the rolling bearing component 12 is first wetted with the fluorescent dye 30. For this purpose, the fluorescent dye 30 is sprayed on, for example, or the rolling bearing component 12 is immersed in the fluorescent dye 30. The fluorescent dye 30 is, for example, a fluorescent dye according to ISO 3452-1 and 3452-2 and / or EN 571 Level three or four, for example Magnaflux ZL-37 from Magnaflux GmbH, Essingen, Germany.

[0061] The fluorescent dye 30 penetrates surface defects, such as crack 33. A portion of the fluorescent dye 30 is then removed, for example, by blowing it off, particularly with compressed air, or rubbing it off with a textile. This can be done automatically or manually.

[0062] The rolling bearing component 12 is then connected, for example, placed on the holder 16, either automatically or manually. The excitation light 22 is emitted, for example, in pulsed form, onto the point of impact A by means of the light source 18. The light pulse emitted by the light source 18 preferably has a duration of no more than 10 ps. Fluorescence photons 28.j emanating from the surface O of the rolling bearing component at the point of impact A are guided by a lens 38 into the same light path in which the excitation light 22 was directed onto the surface O.

[0063] In a beam splitter 40, the fluorescence photons 28.j, which form the excitation light 42, are guided to the single-photon detector 26. This detects a delay time t for each registered fluorescence photon 28.j j at which the fluorescence photon 28.j was registered. This results in a histogram H: t → n(t), which plots the number n of fluorescence photons of the fluorescence photons 28.j registered in a time interval t+Δt against the delay time t.

[0064] Fig. 2a shows a first histogram H1, Fig. Figure 2b shows a second histogram H2. Fig. Figure 2c shows a first image B1, which displays a spatially resolved histogram B: x,y,t → n(t) that represents the number n of fluorescence photons 28.j over the position (x,y). The larger the number n of fluorescence photons, the brighter the corresponding pixel.

[0065] From the evaluation unit 34 (see Fig. 1) those fluorescence photons 28.j can be discriminated whose delay time t j lies outside an acceptance interval I.

[0066] The rolling bearing component 12 is continuously moved by means of a drive of the holder 16, so that the surface O of the rolling bearing component 12 is scanned. The location (x, y) at which the impact point A is located is determined from the speed of the rotational speeds around the vertical axis V on the one hand and the horizontal axis H perpendicular to it. This location (x, y) is assigned to the corresponding histogram.

[0067] Fig. 2d shows an image B2, where a minimum delay time t min of the acceptance interval I = [t min , ... t max] was chosen to discriminate photons caused by reflections or scattering processes. It can be seen that the surface defect F is significantly more visible. The acceptance interval was I = [6 ns, 20 ns].

[0068] The Fig. 2e and Fig. 2f show schematic representations of images B1 and B2 respectively.

[0069] Images B1 and B2 are displayed on screen 36. There, they can be viewed by a person.

[0070] Alternatively, the evaluation unit 34 can determine the maximum brightness value from the spatially resolved delay times B: x,y,t → n(t), which represents an error parameter F. If the error parameter F exceeds a predetermined threshold value F S , the evaluation unit 34 can output an error message. This codes that the rolling bearing component 12 is defective. For example, the rolling bearing component 12 is then automatically rejected.

[0071] Fig. Figure 3 schematically shows an automatic rolling bearing manufacturing device 44 with a system 46 for producing the rolling bearing component 12, for example, a rolling element 14. This element is wetted with the fluorescent dye 30. For this purpose, the rolling elements 14 rest on a conveyor, for example, a chain. For example, the rolling elements 14 are immersed in a fluorescent dye bath.

[0072] Subsequently, the portion of the fluorescent dye 30 not trapped in surface defects is optionally emulsified with an emulsifier. The excess fluorescent dye 30 is then rinsed off with water 48 by a removal device 49 and then placed onto the holder 16 by a robot 50. If the measurement described above reveals that the rolling bearing component 12 is defective, it is conveyed, for example, to a reject container 52. Otherwise, the rolling bearing component 12 is fed to an assembly system 54 for further assembly, thus creating a rolling bearing 56. List of reference symbols 10 Test device 12 Bearing component, rolling bearing component 14 rolling elements 16 recording 18 Light source, laser 20 excitation photons 22 Excitation light (double) 24 detector 26 single-photon detectors 28 fluorescence photons 30 fluorescent dye 32 surface defects, edge zone defects 33 crack 34 Evaluation unit 36 screen 38 lens 40 beam splitters 42 Excitation light (double) 44 Rolling bearing manufacturing device 46 Appendix 48 Water 49 Removal device 50 robots 52 reject containers 54 assembly plant 56 rolling bearings Δt time unit, time interval τ1 first decay constant τ2 second decay constant A Point of impact B Image f1 first decay function f2 second decay function F Surface defects H horizontal axis i counting index j counting index I Acceptance interval M measuring range n Number of fluorescence photons n 0,1first prefactor n 0,2 second prefactor O Surface P error parameters P S Threshold t Delay time t min Minimum delay time V vertical axis x Position coordinates along the surface y Position coordinates along the surface

Claims

[1] Dye penetration method for the non-destructive testing of a bearing component, in particular a rolling bearing component (12), comprising the steps (a) irradiating the bearing component (12) provided with a fluorescent dye (30) with excitation photons (20) so that fluorescence photons (28) are generated, and (b) detecting fluorescence photons (28), characterized by the steps (c) detecting a delay time (t) of the fluorescence photons (28) between the impact of the excitation photons (20) on the bearing component (12) and the emission of the fluorescence photon (28.1) and (d) Determining surface defects (32) of the bearing component (12) based on the delay times (t). [2] Dye penetration method according to claim 1, characterized by the steps (a) applying a fluorescent dye (30) to the bearing component (12) and (b) thereafter and before irradiating the bearing component (12) with excitation photons (20), removing a portion of the fluorescent dye (30). [3] Method according to one of the preceding claims, characterized by that the determination of surface defects (32) of the bearing component (12) based on the delay times (t) comprises the following steps: (a) successively recording the delay times (t) of the fluorescence photons (28) for all points of a measuring area on the surface (O) of the bearing component (12) and (b) issuing a warning message when a surface defect (32) has been detected. [4] Method according to one of the preceding claims, characterized by that the determination of surface defects (32) of the bearing component (12) based on the delay times (t) comprises the following steps: (a) spatially resolved detection of a delay time (t) of the fluorescence photons (28) so that a delay-time-dependent fluorescence photon number (n) is obtained and (b) displaying only those fluorescence photons (28) whose delay times (t) lie within a predetermined acceptance interval (I) in an image (B) and / or Displaying an image (B) showing a ratio of the fluorescence photon numbers two different delay times (t) and / or different spectral ranges. [5] Method according to one of the preceding claims, characterized by that the determination of surface defects (32) of the bearing component (12) based on the delay times (t) comprises the following steps: (a) Adjusting the delay-time dependent fluorescence photon number (n(t)) with (i) a first decay function (f1) which determines the dependence (n(t)) of the fluorescence photons (28) emitted per unit of time on a first decay constant (τ1) and a first, in particular spatially resolved, prefactor (n 0,1 ) and (ii) at least one second decay function which determines the dependence of the fluorescence photons (28) emitted per unit of time on a second decay constant (τ2) which differs from the first decay constant (τ1) and on a second, in particular spatially resolved, prefactor (n 0,2 ) and (b) Determining the surface error (32) from one of the spatially resolved prefactors (n 0,1 , n 0,2 ) and / or displaying the spatially resolved prefactors (n 0,1 , n 0,2 ) in one image (30). [6] Method according to one of the preceding claims, characterized bythat the acceptance interval (I) has a lower limit in the form of a minimum delay time (t min ) which is greater than the flight time of photons reflected or scattered at the bearing component (12). [7] Method according to one of the preceding claims, characterized by that the minimum delay time is greater than the decay time of fluorescent radiation from the material from which the bearing component is made and / or from dirt adhering to the bearing component. [8] Testing device (10) for non-destructive testing of bearing components (12), in particular for surface or edge zone defects (32), with (a) a receptacle (16) for receiving the bearing component (12), (b) a light source (18), in particular a laser, for irradiating the bearing component (12) with excitation photons (20), (c) a detector (24), in particular a camera, for detecting fluorescence photons (28) emitted by the bearing component (12) due to the irradiation, (d) an evaluation unit (34) which is arranged to automatically (i) detecting a delay time (t) of the fluorescence photons (28) between the impact of the excitation photons (20) on the bearing component (12) and the emission of the fluorescence photon (28.1) and (ii) displaying an image (B) of the bearing component (12) based on the fluorescence photons (28) whose delay times (t) lie within a predetermined acceptance interval (I) and / or (iii) calculating at least one error parameter (P) encoding an extent of surface defects (32) of the bearing component (12) from the selected fluorescence photons (28). [9] Test device (10) according to claim 8, characterized by (a) an application device for applying a fluorescent dye (30) to the bearing component (12) and (b) a removal device for removing a portion of the fluorescent dye (30). [10] Rolling bearing manufacturing device (44) for manufacturing a rolling bearing (56) from at least two bearing components (12), with (a) a plant (46) for producing at least one first bearing component (12), (b) a testing device (10) according to one of claims 8 to 9, which is arranged and designed for, in particular automatically, testing this bearing component (12) and (c) if necessary, an assembly system (54) for assembling the rolling bearing (56) using the tested bearing component (12).

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