Stress detection equipment and detection method for ferromagnetic metal parts

Abstract

The present invention relates to a stress detection device for ferromagnetic metal parts and a detection method thereof. The stress detection device for ferromagnetic metal parts comprises a data acquisition and processing device for collecting the normal component of the magnetic field strength; the data acquisition and processing device comprises a first Hall sensor for collecting the normal component of the magnetic field strength of the ferromagnetic metal parts and a second Hall sensor for collecting the normal component of the magnetic field strength of the environment; and also comprises a signal processing module; the two input ends of the signal processing module are respectively connected to the first Hall sensor and the second Hall sensor for communication. The present invention can detect the true normal component of the magnetic field strength in a certain area of ​​the ferromagnetic metal parts through the data acquisition and processing device and the signal processing module, and judge whether there is stress concentration in the area according to the true normal component, so as to predict the potential defects of the ferromagnetic metal parts and prevent the occurrence of safety accidents.

Description

Technical Field

[0001] The present invention relates to the technical field of stress detection equipment, and in particular to stress detection equipment for ferromagnetic metal parts and components and a detection method thereof. Background Art

[0002] Passenger ropeway equipment parts are mostly made of ferromagnetic metal materials. The main reason for their damage is stress corrosion, fatigue cracks and other defects caused by various microscopic and macroscopic mechanical stress concentrations.

[0003] In order to ensure the safe operation of passenger ropeway equipment, it is necessary to conduct regular inspection and supervision of key parts of passenger ropeway. In the inspection process, macroscopic inspection and conventional non-destructive testing methods such as ultrasound, magnetic powder, X-ray, eddy current, and penetration are currently mainly used. These methods are relatively mature and have played an important role in quality control, safety assurance, and accident prevention. However, the above methods can only detect defects that have already occurred, and are insufficient in predicting potential defects in parts, resulting in insufficient ability to prevent accidents, and safety accidents are still inevitable. Summary of the invention

[0004] 1. Technical issues to be resolved

[0005] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides a stress detection device and a detection method for ferromagnetic metal parts, which solves the technical problem that traditional detection means cannot prevent and predict potential defects in passenger ropeway equipment parts.

[0006] (II) Technical solution

[0007] In order to achieve the above object, the main technical solutions adopted by the present invention include:

[0008] Stress detection equipment for ferromagnetic metal parts, including data acquisition and processing equipment;

[0009] The data acquisition and processing device includes a first Hall sensor, a second Hall sensor and a signal processing module;

[0010] The first Hall sensor is capable of collecting the normal component of the magnetic field strength of the ferromagnetic metal component and converting the normal vector into a first voltage signal;

[0011] The second Hall sensor is capable of collecting the normal component of the magnetic field strength of the environment and converting the normal component into a second voltage signal;

[0012] The two input ends of the signal processing module are respectively communicatively connected to the output ends of the first Hall sensor and the second Hall sensor. The signal processing module performs differential calculation on the first voltage signal and the second voltage signal, and processes them to obtain the true normal component of the magnetic field intensity of the measured point of the ferromagnetic metal component.

[0013] Preferably, the distance between the first Hall sensor and the second Hall sensor is 50-100 mm.

[0014] Preferably, the data acquisition and processing device comprises a shell, and the first Hall sensor and the second Hall sensor are located at two ends of the shell.

[0015] Preferably, the shell is made of non-ferromagnetic material.

[0016] Preferably, the first Hall sensor and the second Hall sensor each include a Hall element for collecting the normal component of the magnetic field strength, a data processing module for converting the normal component into a primary voltage signal, and an amplification and filtering module for amplifying and filtering the primary voltage signal to obtain a final voltage signal;

[0017] The two Hall elements are respectively connected to the input ends of the two data processing modules for communication, and the output ends of the two data processing modules are respectively connected to the input ends of the two amplifying and filtering modules for communication.

[0018] Preferably, the signal processing module comprises a differential submodule and a data conversion submodule communicatively connected to an output end of the differential submodule;

[0019] The first input end of the differential submodule is communicatively connected to the output end of the amplifying and filtering module of the first Hall sensor, and the second input end of the differential submodule is communicatively connected to the output end of the amplifying and filtering module of the second Hall sensor.

[0020] Preferably, the output end of the data conversion submodule is communicatively connected to a storage device for storing data and a display screen for displaying a function image of the true normal component.

[0021] The present invention also provides a detection method based on a stress detection device of a ferromagnetic metal component, comprising the following steps:

[0022] S1. Measuring the normal component of the magnetic field strength of the ferromagnetic metal component by the first Hall sensor and converting it into a first voltage signal;

[0023] S2, measuring the normal component of the magnetic field strength of the environment through the second Hall sensor, and converting it into a second voltage signal;

[0024] S3. The signal processing module performs differential processing and data conversion based on the first voltage signal U1 and the second voltage signal to obtain a true normal component of the magnetic field intensity of the measured point of the ferromagnetic metal component.

[0025] Preferably, the differential submodule performs differential processing on the first voltage signal and the second voltage signal to obtain a differential voltage;

[0026] The data conversion submodule obtains the true normal component of the magnetic field intensity of the measured point of the ferromagnetic metal component based on the differential voltage.

[0027] Preferably, the storage device stores the true normal component of the magnetic field strength of the measured point of the ferromagnetic metal component, and the display screen displays a function image of the true normal component of the magnetic field strength of the measured point of the ferromagnetic metal component.

[0028] (III) Beneficial effects

[0029] The beneficial effects of the present invention are as follows: the stress detection sensor for ferromagnetic metal parts of the present invention respectively collects the normal component of the magnetic field strength of the ferromagnetic metal parts and the normal component of the magnetic field strength of the environment through a data acquisition and processing device, and performs differential processing on the normal component of the magnetic field strength of the ferromagnetic metal parts and the normal component of the magnetic field strength of the environment through a signal processing module, thereby reducing the influence of the normal component of the magnetic field strength of the environment on the normal component of the magnetic field strength of the ferromagnetic metal parts, thereby obtaining the real normal component of the magnetic field strength of the ferromagnetic metal parts, judging whether stress concentration exists in a certain area of ​​the ferromagnetic metal parts based on the real normal component, thereby being able to predict potential defects in the ferromagnetic metal parts and prevent the occurrence of safety accidents. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a three-dimensional schematic diagram of the data acquisition and processing device of the present invention;

[0031] Figure 2 for Figure 1 A schematic diagram of the internal structure of the data acquisition and processing device;

[0032] Figure 3 The present invention is a flowchart of the stress detection device for ferromagnetic metal parts.

[0033] [Description of Reference Numerals]

[0034] 1: Workpiece magnetic field measuring head; 2: First Hall sensor; 3: Fixed shell; 4: Connector; 5: Aviation plug; 7: Inner shell; 8: Outer shell; 9: Second Hall sensor; 10: Air magnetic field measuring head. DETAILED DESCRIPTION

[0035] In order to better explain the present invention and facilitate understanding, the present invention is described in detail below through specific implementation modes in conjunction with the accompanying drawings.

[0036] Example 1

[0037] For ferromagnetic metal parts, the residual stress generated by welding affects the ability of the pressure vessel structure to resist stress corrosion cracking. When the stress of the weld and heat-affected zone changes greatly, these parts are prone to cracks. Therefore, if the stress concentration area of ​​the parts can be effectively detected, defects can be prevented, thereby preventing safety accidents.

[0038] During processing and operation of ferromagnetic metal parts, due to the combined effects of load and geomagnetic field, magnetic domain organization with magnetostrictive properties will be oriented and irreversibly reoriented in the stress and deformation concentration areas. This irreversible change of magnetic state is still retained after the working load is removed. This magnetic state on the surface of ferromagnetic metal parts can reflect the microscopic defects or stress concentration locations of the parts. Fixed nodes of magnetic domains will appear in the defective parts of ferromagnetic metal parts. The fixed nodes will generate magnetic poles and form a demagnetization field, thereby minimizing the magnetic permeability here and forming a leakage magnetic field on the metal surface. The tangential component of the leakage magnetic field intensity has a maximum value, while the normal component changes sign and passes through zero.

[0039] In summary, to detect whether there is stress concentration in a certain area of ​​a ferromagnetic metal component, it is only necessary to detect whether the normal component of the magnetic field intensity of the ferromagnetic metal component in the area changes its sign and passes through the zero point.

[0040] like Figures 1 to 3 As shown, the stress detection equipment for ferromagnetic metal parts includes a data acquisition and processing device.

[0041] The data acquisition and processing device comprises a first Hall sensor 2, a second Hall sensor 9 and a signal processing module.

[0042] The first Hall sensor 2 can collect the normal component of the magnetic field strength of the ferromagnetic metal component and convert the normal vector into a first voltage signal.

[0043] The second Hall sensor 9 can detect the normal component of the magnetic field strength of the environment and convert the normal component into a second voltage signal.

[0044] The two input ends of the signal processing module are respectively communicatively connected to the output ends of the first Hall sensor 2 and the second Hall sensor 9 to receive the first voltage signal and the second voltage signal emitted by the first Hall sensor 2 and the second Hall sensor 9. The signal processing module performs differential calculation on the first voltage signal and the second voltage signal, and processes them to obtain the true normal component of the magnetic field strength of the measured point of the ferromagnetic metal component.

[0045] When the present invention is used, the first Hall sensor 2 measures the normal component H of the magnetic field strength of the ferromagnetic metal component. 1(y) , and the normal component H of the magnetic field strength of the ferromagnetic metal parts 1(y) The normal component H of the magnetic field strength of the environment of the second Hall sensor 9 is converted into a first voltage signal U1, that is, the telecommunication signal finally output by the first Hall sensor 2 is the first voltage signal U1. 2(y) , and the normal component H of the ambient magnetic field strength 2(y) Converted into the second voltage signal U2, that is, the voltage signal finally output by the second Hall sensor is the second voltage signal U2.

[0046] In this embodiment, the first Hall sensor 2 and the second Hall sensor 9 are Hall sensors of the same specification, that is, the first Hall sensor 2 and the second Hall sensor 9 have the same sensitivity, and the current I passing through the first Hall sensor 2 and the second Hall sensor 9 is consistent in magnitude.

[0047] The calculation formulas of the first voltage signal U1 and the second voltage signal U2 are:

[0048] U i =αK H Iμ0H i(y) (1)

[0049] In the formula, i is 1 or 2;

[0050] K H —Sensitivity of the Hall element;

[0051] α—the amplification factor of the signal by the amplification filter module;

[0052] I—Current passing through the Hall element;

[0053] μ0—4π×10 -7 , is the magnetic constant.

[0054] When i is 1, U1 is the first voltage signal, H 1(y) is the normal component of the magnetic field strength of the ferromagnetic metal parts. When i is 2, U2 is the second voltage signal, H 2(y) is the normal component of the ambient magnetic field strength.

[0055] The signal processing module first performs differential processing on the first voltage signal U1 and the second voltage signal U2 to obtain U. The calculation formula of the differential voltage U is: U = U1-U2 (2)

[0056] The signal processing module then converts the differential voltage U to obtain the true normal component H of the magnetic field intensity at the measured point of the ferromagnetic metal component. (y), the calculation formula of the true normal component is:

[0057]

[0058] In the formula, K H —Sensitivity of the Hall element;

[0059] α—the amplification factor of the signal by the amplification filter module;

[0060] I—Current passing through the Hall element;

[0061] μ0—4π×10 -7 , is the magnetic constant.

[0062] like Figure 2 As shown, in order to prevent the value of the environmental voltage signal U2 measured by the second Hall sensor 9 from being affected by ferromagnetic metal parts, the distance between the first Hall sensor 2 and the second Hall sensor 9 is 50-100 mm.

[0063] like Figures 1-2 As shown, for the convenience of measurement, the data acquisition and processing device further includes a shell for accommodating the first Hall sensor 2 and the second Hall sensor 9, and the first Hall sensor 2 and the second Hall sensor 9 are separated at two ends of the shell.

[0064] like Figures 1-2 As shown, the shell includes an outer shell 8 and an inner shell 7, both of which are cylindrical structures, and the outer shell 8 is sleeved on the outside of the inner shell 7. A fixed shell 3 is sleeved on the outer side of the upper part of the outer shell 8, and the fixed shell 3 is connected to the outer shell 8 and the inner shell 7 by bolts. A rib is provided at the bottom of the outer shell 8 extending radially inward, and a gap is left between the top of the rib and the bottom of the inner shell 7, and an air magnetic field measuring head 10 is clamped in the gap. A workpiece magnetic field measuring head 1 is provided at the upper end of the outer shell 8, and a fixed rib extends radially outward at the bottom of the workpiece magnetic field measuring head 1. The fixed rib and the fixed shell 3 fix the workpiece magnetic field measuring head 1. The top of the workpiece magnetic field measuring head 1 extends out of the fixed shell 3, and the bottom of the air magnetic field measuring head 10 extends out of the outer shell 8.

[0065] like Figure 2 As shown, the first Hall sensor 2 is placed in the workpiece magnetic field measuring head 1 , and the second Hall sensor 9 is placed in the air magnetic field measuring head 10 .

[0066] like Figure 2As shown, a connection hole is provided on the shell 8, and a connector 4 is fixedly connected in the connection hole. The fixed connection can be welding or riveting, etc., as long as the connector 4 can be fixed in the connection hole. A through hole corresponding to the connection hole is provided on the fixed shell 3. The internal thread of the connector 4 is connected to the input end of the aviation plug 5, and the output end of the aviation plug 5 extends out of the through hole. The two input ends of the aviation plug 5 are respectively connected to the first Hall sensor 2 and the second Hall sensor 9 for communication, and the two output ends of the aviation plug 5 are both connected to the input end of the signal processing module for communication.

[0067] When in use, the workpiece magnetic field measuring head 1 is fitted with the measured point of the ferromagnetic metal component, and the workpiece magnetic field measuring head 1 is perpendicular to the measured point of the ferromagnetic metal component. The first Hall sensor 2 collects data on the normal vector of the magnetic field strength of the ferromagnetic metal component to obtain U1, and the second Hall sensor 9 collects data on the normal vector of the magnetic field strength of the environment to obtain U2. The workpiece magnetic field measuring head 1 moves on the surface of the ferromagnetic metal component to obtain the normal components of the strong magnetic intensity of multiple points on the ferromagnetic metal component and the normal components of multiple environmental magnetic field strengths.

[0068] Furthermore, in order to prevent the shell from affecting the magnetic field intensity collected by the first Hall sensor 2 and the second Hall sensor 9, the shell is made of non-ferromagnetic material, such as aluminum, plastic, and glass. The magnetic permeability of non-magnetic materials is very small, and the magnetic field can pass through non-magnetic materials. Therefore, the shell is made of non-magnetic material and does not affect the first Hall sensor 2 and the second Hall sensor 9 to measure the magnetic field intensity. As an example, the material of the shell in this embodiment is aluminum.

[0069] As an example, the first Hall sensor 2 and the second Hall sensor 9 each include a Hall element, a data processing module and an amplification and filtering module. The data processing module is used to collect the normal component of the magnetic field strength and convert the normal component into a primary voltage signal, and the amplification and filtering module is used to amplify the primary voltage signal and perform filtering processing to obtain a final voltage signal.

[0070] The two Hall elements are respectively connected to the two input ends of the data processing module for communication, and the output ends of the two data processing modules are respectively connected to the input ends of the two amplifying and filtering modules for communication.

[0071] The Hall element of the first Hall sensor 2 measures the normal component H of the magnetic field strength of the ferromagnetic metal component. 1(y) The data processing module and the amplification and filtering module of the first Hall sensor 2 are based on the normal component H of the magnetic field strength of the ferromagnetic metal parts. 1(y) The final voltage signal of the first Hall sensor 2, namely the first voltage signal U1, is obtained. The Hall element of the second Hall sensor 9 measures the normal component H of the magnetic field strength of the environment. 2(y) The data processing module is based on the normal component H of the magnetic field strength of the environment2(y) The final voltage signal of the second Hall sensor 9 is obtained, that is, the second voltage signal U2. The calculation of the first voltage signal U1 and the second voltage signal U2 is shown in Formula 1.

[0072] Furthermore, in order to reduce the influence of the environmental magnetic field strength on the magnetic field strength of the ferromagnetic metal component, the signal processing module includes a differential submodule and a data conversion submodule communicatively connected to the output end of the differential submodule.

[0073] The first input end of the differential submodule is communicatively connected to the output end of the amplifying and filtering module of the first Hall sensor 2 to receive the first voltage signal emitted by the first Hall sensor 2. The second input end of the differential submodule is communicatively connected to the output end of the amplifying and filtering module of the second Hall sensor 9 to receive the second voltage signal emitted by the second Hall sensor 9.

[0074] The differential submodule obtains a differential voltage U based on the first voltage signal U1 of the ferromagnetic metal component and the voltage signal U2 of the environment. The calculation of the differential voltage U is shown in Formula 2.

[0075] The data conversion submodule obtains the true normal component H of the magnetic field intensity of the measured point of the ferromagnetic metal component based on the differential voltage U. (y) The conversion of the true normal component is shown in Formula 3.

[0076] like Figure 3 As shown, in order to conveniently observe and record whether there is stress concentration in the measured ferromagnetic metal parts, the output end of the data conversion submodule is connected to a storage device for storing data and a real normal component H for displaying the magnetic field strength of the measured point of the ferromagnetic metal parts. (y) The display screen is electrically connected to an alarm. When the true normal component H of the magnetic field intensity (y) When the function graph passes through zero and the sign changes, the alarm goes off to alert the staff.

[0077] Detect the true normal component H of the magnetic field strength at multiple points in a certain area of ​​a ferromagnetic metal component (y) , and plot it as a function graph and present it on the display screen, so that it can be easily observed whether the normal component of the area changes its sign and passes through zero, thereby judging whether there is stress concentration in the area of ​​the ferromagnetic metal part. When there is stress concentration in the ferromagnetic metal part, the alarm will sound to remind the staff. Among them, the true normal vector H (y) The horizontal axis of the function graph represents the defect centerline, and the vertical axis represents the true normal vector H (y) The value of .

[0078] Example 2

[0079] like Figure 3As shown, in this embodiment, a detection method of the stress detection device of the ferromagnetic metal parts based on the embodiment 1 is provided, comprising the following steps:

[0080] S1, measuring the normal component of the magnetic field strength of the ferromagnetic metal component by the first Hall sensor 2, and converting it into a first voltage signal to obtain U1;

[0081] S2, measuring the normal component of the magnetic field strength of the environment through the second Hall sensor 9, and converting it into a second voltage signal to obtain U2;

[0082] S3, the signal processing module performs differential processing and data conversion based on the first voltage signal U1 and the second voltage signal U2 to obtain the true normal component H of the magnetic field intensity of the measured point of the ferromagnetic metal component (y) .

[0083] The Hall element of the first Hall sensor 2 measures the normal component H of the magnetic field strength of the ferromagnetic metal component. 1(y) The data processing module and the amplification and filtering module of the first Hall sensor 2 are based on the normal component H of the magnetic field strength of the ferromagnetic metal parts. 1(y) The final voltage signal of the first Hall sensor 2, namely the first voltage signal U1, is obtained. The Hall element of the second Hall sensor 9 measures the normal component H of the magnetic field strength of the environment. 2(y) The data processing module is based on the normal component H of the magnetic field strength of the environment 2(y) The final voltage signal of the second Hall sensor 9 , ie, the second voltage signal U2 , is obtained.

[0084] When in use, the first Hall sensor 2 and the second Hall sensor 9 are Hall sensors of the same specification, that is, the first Hall sensor 2 and the second Hall sensor 9 have the same sensitivity, and the current I passing through the first Hall sensor 2 and the second Hall sensor 9 is consistent in magnitude.

[0085] For calculation of the first voltage signal U1 and the second voltage signal U2, refer to Formula 1 in Embodiment 1.

[0086] The signal processing module first performs differential processing on the first voltage signal U1 and the second voltage signal U2 to obtain U. The calculation formula of the differential voltage U refers to Formula 2 in Example 1.

[0087] The signal processing module then converts the differential voltage U to obtain the true normal component H of the magnetic field intensity at the measured point of the ferromagnetic metal component. (y) , the true normal component H (y) For the calculation formula of , see Formula 3 in Example 1.

[0088] The storage device stores the true normal component H of the magnetic field intensity at the measured point of the ferromagnetic metal component. (y)Detect the normal component H of the magnetic field strength at multiple points in a certain area of ​​ferromagnetic metal parts (y) , and plot it as a function graph and present it on the display screen, so that it is easy to observe whether the normal component of the area changes its sign and passes through zero, thereby judging whether there is stress concentration in the area of ​​the ferromagnetic metal component.

[0089] Among them, the true normal vector H (y) The horizontal axis of the function graph represents the defect centerline, and the vertical axis represents the true normal vector H (y) The value of .

[0090] In the description of the present invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0091] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0092] In the present invention, unless otherwise clearly specified and limited, when a first feature is “on” or “below” a second feature, it may be that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, when a first feature is “above”, “above” or “above” a second feature, it may be that the first feature is directly above or obliquely above the second feature, or it may simply mean that the first feature is higher in level than the second feature. When a first feature is “below”, “below” or “below” a second feature, it may be that the first feature is directly below or obliquely below the second feature, or it may simply mean that the first feature is lower in level than the second feature.

[0093] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "embodiment", "example", "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

[0094] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may alter, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A stress detection device for ferromagnetic metal parts, characterized in that: It includes a data acquisition and processing device; The data acquisition and processing device comprises a first Hall sensor (2), a second Hall sensor (9) and a signal processing module; The data acquisition and processing device also includes a housing for accommodating a first Hall sensor (2) and a second Hall sensor (9), wherein the first Hall sensor (2) and the second Hall sensor (9) are located at two ends of the housing; The shell comprises an outer shell (8) and an inner shell (7), the inner shell (7) and the outer shell (8) both being cylindrical structures, the outer shell (8) being sleeved on the outer side of the inner shell (7); a fixed shell (3) being sleeved on the outer side of the upper part of the outer shell (8), the fixed shell (3) being connected to the outer shell (8) and the inner shell (7) by bolts; a rib extending radially inwardly from the bottom of the outer shell (8), a gap being left between the top of the rib and the bottom of the inner shell (7), an air magnetic field measuring head (10) being clamped in the gap; a workpiece magnetic field measuring head (1) being provided at the inner upper end of the outer shell (8), a fixed rib extending radially outwardly from the bottom of the workpiece magnetic field measuring head (1); the fixed rib and the fixed shell (3) fixing the workpiece magnetic field measuring head (1); the top of the workpiece magnetic field measuring head (1) extending out of the fixed shell (3), the bottom of the air magnetic field measuring head (10) extending out of the outer shell (8); The first Hall sensor (2) is placed in the workpiece magnetic field measuring head (1), and the second Hall sensor (9) is placed in the air magnetic field measuring head (10); The first Hall sensor (2) is capable of collecting the normal component of the magnetic field strength of the ferromagnetic metal component and converting the normal component into a first voltage signal; The second Hall sensor (9) is capable of collecting the normal component of the magnetic field strength of the environment and converting the normal component into a second voltage signal; The two input ends of the signal processing module are respectively connected to the output ends of the first Hall sensor (2) and the second Hall sensor (9), and the signal processing module performs differential calculation on the first voltage signal and the second voltage signal, and processes them to obtain a true normal component of the magnetic field intensity of the measured point of the ferromagnetic metal component.

2. The stress detection device for ferromagnetic metal parts according to claim 1, characterized in that: The distance between the first Hall sensor (2) and the second Hall sensor (9) is 50-100 mm.

3. The stress detection device for ferromagnetic metal parts according to claim 1, characterized in that: The shell is made of non-ferromagnetic material.

4. The stress detection device for ferromagnetic metal parts according to claim 1, characterized in that: The first Hall sensor (2) and the second Hall sensor (9) each comprise a Hall element for collecting a normal component of magnetic field intensity, a data processing module for converting the normal component into a primary voltage signal, and an amplification and filtering module for amplifying and filtering the primary voltage signal to obtain a final voltage signal; The two Hall elements are respectively connected to the input ends of the two data processing modules for communication, and the output ends of the two data processing modules are respectively connected to the input ends of the two amplifying and filtering modules for communication.

5. The stress detection device for ferromagnetic metal parts according to claim 4, characterized in that: The signal processing module includes a differential submodule and a data conversion submodule communicatively connected to an output end of the differential submodule; The first input end of the differential submodule is communicatively connected to the output end of the amplifying and filtering module of the first Hall sensor (2), and the second input end of the differential submodule is communicatively connected to the output end of the amplifying and filtering module of the second Hall sensor (9).

6. The stress detection device for ferromagnetic metal parts according to claim 5, characterized in that: The output end of the data conversion submodule is communicatively connected to a storage device for storing data and a display screen for displaying a function image of the real normal component.

7. The stress detection method for ferromagnetic metal parts according to claim 6, characterized in that: The following steps are involved: S1. Measuring the normal component of the magnetic field strength of the ferromagnetic metal component by means of the first Hall sensor (2), and converting it into a first voltage signal; S2, measuring the normal component of the magnetic field strength of the environment by means of the second Hall sensor (9), and converting it into a second voltage signal; S3. The signal processing module performs differential processing and data conversion based on the first voltage signal U1 and the second voltage signal to obtain a true normal component of the magnetic field intensity of the measured point of the ferromagnetic metal component.

8. The stress detection method for ferromagnetic metal parts according to claim 7, characterized in that: The differential submodule performs differential processing based on the first voltage signal and the second voltage signal to obtain a differential voltage; The data conversion submodule obtains the true normal component of the magnetic field intensity of the measured point of the ferromagnetic metal component based on the differential voltage.

9. The stress detection method for ferromagnetic metal parts according to claim 7, characterized in that: The storage device stores the true normal component of the magnetic field strength of the measured point of the ferromagnetic metal component, and the display screen displays a function image of the true normal component of the magnetic field strength of the measured point of the ferromagnetic metal component.

Images