Bolt state monitoring method and system, electronic equipment and medium

Abstract

The invention relates to the technical field of bolt monitoring, in particular to a bolt state monitoring method and system, electronic equipment and a medium, and the method comprises the steps: obtaining the propagation speeds of ultrasonic waves in different propagation directions in a bolt in real time; according to the current propagation speed of the ultrasonic waves in different propagation directions, the current axial stress state borne by the bolt is determined; and monitoring the current state of the bolt according to the current axial stress state. The bolt is monitored through the ultrasonic technology, pertinence is high, influences of other abnormal factors are avoided, and accuracy is high.

Description

Background Art

[0002] Connecting bolts are an indispensable and important part in fastening connections and are widely used in various machines and structures. Currently, the monitoring of connecting bolts is mainly done by observing their status with the naked eye, and it is difficult to determine whether their internal structure is damaged. When bolts break due to strength or fatigue, it will seriously affect the operation of the machine.

[0003] The existing technology for monitoring bolts of machinery is mainly to obtain the operating parameters of the machinery, and then judge whether the bolts are faulty based on the operating parameters. However, the above method may cause misjudgment, especially when the machinery has abnormal working conditions other than bolt problems, the operating parameters will also be abnormal. Summary of the invention

[0004] In order to overcome the problem of misjudgment of bolt faults in the prior art by using operating parameters, the present invention provides a bolt status monitoring method, system, electronic equipment and medium.

[0005] In a first aspect, in order to solve the above technical problems, the present invention provides a bolt state monitoring method, comprising:

[0006] Obtain the propagation speed of ultrasonic waves in different propagation directions in the bolt in real time;

[0007] According to the current propagation speed of the ultrasonic wave in different propagation directions, the current axial stress state of the bolt is determined;

[0008] The current state of the bolt is monitored according to the current axial stress state.

[0009] In a second aspect, the present invention provides a bolt state monitoring system, comprising:

[0010] A propagation velocity acquisition module is used to obtain the propagation velocity of ultrasonic waves in different propagation directions in the bolt in real time;

[0011] A current axial stress state determination module is used to determine the current axial stress state of the bolt according to the current propagation speed of the ultrasonic wave in different propagation directions;

[0012] The monitoring module is used to monitor the current state of the bolt according to the current axial stress state.

[0013] In a third aspect, the present invention provides a computing device, including a memory, a processor, and a program stored in the memory and running on the processor, and when the processor executes the program, the steps of a bolt status monitoring method as described above are implemented.

[0014] In a fourth aspect, the present invention provides a computer-readable storage medium, in which instructions are stored. When the instructions are executed on a terminal device, the terminal device executes the steps of a bolt status monitoring method as described above.

[0015] The beneficial effect of the present invention is that by obtaining the propagation speed of ultrasound in different directions in the bolt, the axial stress state of the bolt is solved according to the propagation speed, and the bolt is monitored according to the axial stress state. The present application monitors the bolt by ultrasonic technology, which is highly targeted, not affected by other abnormal factors, and has high accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0017] Figure 1 A schematic diagram of a flow chart of a bolt status monitoring method according to an embodiment of the present invention;

[0018] Figure 2 The figure is a schematic diagram of the structure of a bolt status monitoring system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0019] The following examples are provided to further explain and supplement the present invention and do not constitute any limitation to the present invention.

[0020] A bolt status monitoring method, system, electronic device and medium according to an embodiment of the present invention are described below in conjunction with the accompanying drawings.

[0021] like Figure 1 As shown, the present invention provides a bolt state monitoring method, comprising:

[0022] S1. Obtain the propagation speed of ultrasonic waves in different propagation directions in the bolt in real time.

[0023] S2. Determine the current axial stress state of the bolt according to the current propagation speed of the ultrasonic wave in different propagation directions.

[0024] S3. Monitor the current state of the bolt according to the current axial stress state.

[0025] In this embodiment, the propagation speed of ultrasonic waves in different directions in the bolt is obtained, so as to solve the axial stress state of the bolt according to the propagation speed, and monitor the bolt according to the axial stress state. This application uses ultrasonic technology to monitor the bolt, which is highly targeted, not affected by other abnormal factors, and has high accuracy.

[0026] In this embodiment, it is known from the basic characteristics of ultrasound that when a wave encounters an obstacle, it will be reflected. When the geometric size of the obstacle is large relative to the wavelength, the sound wave will not be able to continue to propagate forward and will be completely reflected (refracted); when the geometric size of the obstacle is small relative to the wavelength, the sound wave will bypass the obstacle and continue to propagate forward along the previous path. When there is a crack in the root of the bolt tooth, the original root part will increase the blocking effect of the sound wave, and the sound waves that could bypass the root part will be blocked in large quantities. As the crack extends in depth, the sound waves that were not blocked will also be reflected back, which will affect the propagation speed of the ultrasonic wave in the bolt, thereby detecting whether there is a crack.

[0027] This method is applicable to any machine using bolts, such as a wind turbine, and is also applicable to scenes corresponding to the above-mentioned machines, such as a wind power station and a wind power plant.

[0028] Optionally, determining the current axial stress state of the bolt according to the current propagation speed of the ultrasonic wave in different propagation directions includes:

[0029] Obtaining the current first propagation velocity of the ultrasonic shear wave propagating in the bolt;

[0030] Obtaining the current second propagation velocity of the ultrasonic longitudinal wave propagating in the bolt;

[0031] The current axial stress state of the bolt is determined according to the current first propagation velocity and the current second propagation velocity.

[0032] In this embodiment, an ultrasonic high-frequency probe needs to be set at the station to be tested. The commonly used ultrasonic high-frequency probes are: longitudinal wave oblique probe and transverse wave oblique probe. When the two end faces of the bolt are flat, a longitudinal wave small-angle probe (the angle is determined by the length of the threaded area and the end face diameter to be detected) is used to scan the opposite side of one end face, and then a transverse wave oblique probe is used to scan.

[0033] In this embodiment, when the bolt is damaged and defective, the axial stress of the bolt will change, thereby affecting the speed at which the ultrasonic wave propagates in the bolt. Based on this, by monitoring the propagation speed of the ultrasonic wave in different directions in the bolt, it is possible to determine whether the axial stress of the bolt is abnormal, and then determine whether the bolt has defects.

[0034] Optionally, determining a current axial stress state of the bolt according to the current first propagation velocity and the current second propagation velocity includes:

[0035] Obtain the longitudinal wave sound velocity when the stress is 0 at standard temperature, and the shear wave sound velocity when the stress is 0 at standard temperature;

[0036] According to the current first propagation velocity, the current second propagation velocity, the longitudinal wave speed of sound and the transverse wave speed of sound, the current axial stress state of the bolt is determined. The formula is as follows:

[0037] V Lσ =v L0 (1+k L σ1)

[0038] v Sσ =v S0 (1+k S σ2)

[0039] Among them, V Lσ is the second propagation velocity when the stress is σ1 at standard temperature, V L0 represents the longitudinal wave speed, k L represents the Lame constant, V Sσ is the first propagation velocity when the stress is σ2 at standard temperature, V S0 represents the shear wave speed, k S represents the Murnaghan constant, σ1 and σ2 represent the longitudinal stress and transverse stress respectively. The current axial stress state includes longitudinal stress and transverse stress.

[0040] In this embodiment, according to the acoustic elasticity principle, when the ultrasonic wave propagation direction is parallel to the stress, the mathematical relationship can be obtained as follows:

[0041]

[0042]

[0043] Where ρ0 represents the density of the solid under zero stress, V Lσ is the longitudinal wave sound velocity when the axial stress is σ1 at standard temperature, σ1 represents the longitudinal stress, V Sσ is the transverse wave sound velocity when the stress is σ2 at standard temperature, σ2 represents the transverse stress, λ and μ are the Lame constants of the material, and m, n, and l are the Murnaghan constants of the material.

[0044] When the zero stress state in formula (1) and formula (2) is σ1=σ2=0, we can get:

[0045]

[0046]

[0047] Among them, V L0 It represents the longitudinal wave speed when the stress is 0 at standard temperature, V S0 It represents the shear wave speed when the stress is 0 at standard temperature.

[0048] Substituting formula (3) and formula (4) into formula (1) and formula (2), we can obtain the following simplified formula:

[0049]

[0050]

[0051] Among them, k L represents the Lame constant, k S Represents the Murnaghan constant.

[0052] According to Taylor's formula, formula (5) and formula (6) are simplified to obtain:

[0053] v Lσ =v L0 (1+k L σ1)

[0054] v Sσ =v S0 (1+k S σ2).

[0055] Optionally, the current state of the bolt is monitored according to the current axial stress state, including:

[0056] If the longitudinal stress is within the first preset range, the current state of the bolt is healthy;

[0057] If the longitudinal stress is not within the first preset range, the current state of the bolt is defective;

[0058] If the transverse stress is within the second preset range, the current state of the bolt is healthy;

[0059] If the transverse stress is not within the second preset range, the current state of the bolt is defective.

[0060] In this embodiment, the first preset range and the second preset range can be set according to actual conditions. Preferably, in this embodiment, the first preset range and the second preset range are set to the same value, both of which are 1220Pa-1514Pa.

[0061] Optionally, monitoring the current state of the bolt according to the current axial stress state further includes:

[0062] If the current state of the bolt is defective, an early warning is issued.

[0063] In this embodiment, the corresponding level of warning can be set according to the different ranges of the transverse stress and the longitudinal stress, as shown in the following examples:

[0064] If the lateral stress or longitudinal stress falls within 1220Pa-1514Pa, the current state of the surface is healthy and no warning is issued.

[0065] If the transverse stress or longitudinal stress falls between 1000Pa-1220Pa or 1514Pa-1700Pa, slight defects will appear on the surface of the bolts.

[0066] If the transverse stress or longitudinal stress is less than 1000Pa or greater than 1700Pa, severe defects will occur in the surface bolts.

[0067] In this embodiment, the monitoring personnel can execute corresponding remedial measures according to different degrees of warning.

[0068] like Figure 2 As shown, the present invention provides a bolt condition monitoring system, comprising:

[0069] A propagation velocity acquisition module is used to obtain the propagation velocity of ultrasonic waves in different propagation directions in the bolt in real time;

[0070] A current axial stress state determination module is used to determine the current axial stress state of the bolt according to the current propagation speed of the ultrasonic wave in different propagation directions;

[0071] The monitoring module is used to monitor the current state of the bolt according to the current axial stress state.

[0072] Optionally, the current axial stress state determination module is specifically used to:

[0073] Obtaining the current first propagation velocity of the ultrasonic shear wave propagating in the bolt;

[0074] Obtaining the current second propagation velocity of the ultrasonic longitudinal wave propagating in the bolt;

[0075] The current axial stress state of the bolt is determined according to the current first propagation velocity and the current second propagation velocity.

[0076] Optionally, the current axial stress state determination module is specifically used to:

[0077] Obtain the longitudinal wave sound velocity when the stress is 0 at standard temperature, and the shear wave sound velocity when the stress is 0 at standard temperature;

[0078] According to the current first propagation velocity, the current second propagation velocity, the longitudinal wave speed of sound and the transverse wave speed of sound, the current axial stress state of the bolt is determined. The formula is as follows:

[0079] v Lσ =v L0 (1+k L σ1)

[0080] vSσ =v S0 (1+k S σ2)

[0081] Among them, V Lσ is the second propagation velocity when the stress is σ1 at standard temperature, V L0 represents the longitudinal wave speed, k L represents the Lame constant, V Sσ is the first propagation velocity when the stress is σ2 at standard temperature, V S0 represents the shear wave speed, k S represents the Murnaghan constant, σ1 and σ2 represent the longitudinal stress and transverse stress respectively. The current axial stress state includes longitudinal stress and transverse stress.

[0082] Optionally, the monitoring module is specifically used to:

[0083] If the longitudinal stress is within the first preset range, the current state of the bolt is healthy;

[0084] If the longitudinal stress is not within the first preset range, the current state of the bolt is defective;

[0085] If the transverse stress is within the second preset range, the current state of the bolt is healthy;

[0086] If the transverse stress is not within the second preset range, the current state of the bolt is defective.

[0087] Optionally, the system further includes an early warning module, specifically used for:

[0088] If the current state of the bolt is defective, an early warning is issued.

[0089] An embodiment of the present invention also provides a computing device, including a memory, a manager, and a program stored in the memory and running on the manager. When the manager executes the program, some or all steps of the above-mentioned bolt status monitoring method are implemented.

[0090] Among them, the computing device can be a computer, and correspondingly, its program is computer software. The above-mentioned parameters and steps in the computing device of the present invention can refer to the parameters and steps in the embodiment of a bolt state monitoring method mentioned above, and will not be repeated here.

[0091] Those skilled in the art know that the present invention can be implemented as a system, method or computer program product. Therefore, the present disclosure can be specifically implemented in the following forms, namely: it can be complete hardware, it can be complete software (including firmware, resident software, microcode, etc.), or it can be a combination of hardware and software, generally referred to as "circuit", "module" or "system" herein. In addition, in some embodiments, the present invention can also be implemented in the form of a computer program product in one or more computer-readable media, and the computer-readable medium contains computer-readable program code. Computer-readable storage media can be, for example, but not limited to - electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices or devices, or any combination of the above.

[0092] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "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, without contradiction.

[0093] 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 change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A bolt condition monitoring method, characterized in that: include: Obtain the propagation speed of ultrasonic waves in different propagation directions in the bolt in real time; Determining a current axial stress state of the bolt according to the current propagation speed of the ultrasonic wave in different propagation directions; The current state of the bolt is monitored according to the current axial stress state.

2. The method according to claim 1, characterized in that: Determining the current axial stress state of the bolt according to the current propagation speed of the ultrasonic wave in different propagation directions includes: Obtaining the current first propagation velocity of the ultrasonic shear wave propagating in the bolt; Obtaining the current second propagation velocity of the ultrasonic longitudinal wave propagating in the bolt; A current axial stress state of the bolt is determined according to the current first propagation velocity and the current second propagation velocity.

3. The method according to claim 2, characterized in that The determining, according to the current first propagation velocity and the current second propagation velocity, a current axial stress state of the bolt comprises: Obtain the longitudinal wave sound velocity when the stress is 0 at standard temperature, and the shear wave sound velocity when the stress is 0 at standard temperature; According to the current first propagation velocity, the current second propagation velocity, the longitudinal wave speed of sound and the transverse wave speed of sound, the current axial stress state of the bolt is determined, and the formula is as follows: V Lσ =V L0 (1+k L σ1) V sσ =V s0 (1+k S σ2) Among them, V Lσ is the second propagation velocity when the stress is σ1 at standard temperature, V L0 represents the longitudinal wave speed, k L represents the Lame constant, V Sα is the first propagation velocity when the stress is σ2 at standard temperature, V S0 represents the shear wave speed, k S represents the Murnaghan constant, σ1 and σ2 represent the longitudinal stress and transverse stress respectively. The current axial stress state includes longitudinal stress and transverse stress.

4. The method according to claim 3, characterized in that: The monitoring of the current state of the bolt according to the current axial stress state includes: If the longitudinal stress is within the first preset range, the current state of the bolt is healthy; If the longitudinal stress is not within the first preset range, the current state of the bolt is defective; If the transverse stress is within the second preset range, the current state of the bolt is healthy; If the transverse stress is not within the second preset range, the current state of the bolt is defective.

5. The method according to any one of claims 1 to 4, characterized in that: The monitoring of the current state of the bolt according to the current axial stress state further includes: If the current state of the bolt is defective, an early warning is issued.

6. A bolt condition monitoring system, characterized in that: include: A propagation velocity acquisition module is used to obtain the propagation velocity of ultrasonic waves in different propagation directions in the bolt in real time; A current axial stress state determination module, used to determine the current axial stress state of the bolt according to the current propagation speed of the ultrasonic wave in different propagation directions; The monitoring module is used to monitor the current state of the bolt according to the current axial stress state.

7. The system according to claim 6, characterized in that The current axial stress state determination module is specifically used for: Obtaining the current first propagation velocity of the ultrasonic shear wave propagating in the bolt; Obtaining the current second propagation velocity of the ultrasonic longitudinal wave propagating in the bolt; A current axial stress state of the bolt is determined according to the current first propagation velocity and the current second propagation velocity.

8. The system according to claim 7, characterized in that The current axial stress state determination module is specifically used for: Obtain the longitudinal wave sound velocity when the stress is 0 at standard temperature, and the shear wave sound velocity when the stress is 0 at standard temperature; According to the current first propagation velocity, the current second propagation velocity, the longitudinal wave speed of sound and the transverse wave speed of sound, the current axial stress state of the bolt is determined, and the formula is as follows: V Lσ =V L0 (1+k L σ1) V Sσ =V S0 (1+k S σ2) Among them, V Lσ is the second propagation velocity when the stress is σ1 at standard temperature, V L0 represents the longitudinal wave speed, k L represents the Lame constant, V Sσ is the first propagation velocity when the stress is σ2 at standard temperature, V S0 represents the shear wave speed, k S represents the Murnaghan constant, σ1 and σ2 represent the longitudinal stress and transverse stress respectively. The current axial stress state includes longitudinal stress and transverse stress.

9. A computing device comprising a memory, a processor, and a program stored in the memory and running on the processor, characterized in that: When the processor executes the program, the steps of a bolt condition monitoring method as described in any one of claims 1 to 5 are implemented.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores instructions, and when the instructions are executed on a terminal device, the terminal device executes the steps of a bolt status monitoring method as described in any one of claims 1 to 5.

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