CN115683409A - Ultrasonic measurement method and system for residual clamping force of bolt plastic area - Google Patents
Ultrasonic measurement method and system for residual clamping force of bolt plastic area Download PDFInfo
- Publication number
- CN115683409A CN115683409A CN202110876279.XA CN202110876279A CN115683409A CN 115683409 A CN115683409 A CN 115683409A CN 202110876279 A CN202110876279 A CN 202110876279A CN 115683409 A CN115683409 A CN 115683409A
- Authority
- CN
- China
- Prior art keywords
- bolt
- sound
- ultrasonic
- standard curve
- acquiring
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Landscapes
- Force Measurement Appropriate To Specific Purposes (AREA)
Abstract
The embodiment of the application relates to the technical field of bolt pretightening force detection, in particular to an ultrasonic measurement method and system for residual clamping force of a bolt plastic area. And establishing a corresponding relation between the stress borne by the bolt and the ultrasonic flight time to obtain a standard curve table. After the bolt is subjected to a road test, the bolt is detached and annealed, residual stress deviation caused by plastic deformation of the bolt is eliminated, and then the sound time value of the bolt in a free state is detected, so that the precision of the sound time value of the free state ultrasonic wave is effectively improved. The sound time value difference of two sound time values of the clamping state and the free state is obtained through calculation, the sound time value difference is substituted into the standard curve table, the residual clamping force of the bolt can be obtained, and the accuracy of the finally measured residual clamping force is effectively improved.
Description
Technical Field
The embodiment of the application relates to the technical field of bolt pretightening force detection, in particular to an ultrasonic measurement method and system for residual clamping force of a bolt plastic area.
Background
Bolted connections are a common connection mode in automotive design, and reasonable bolt clamping force is a main target of connection design. In order to improve the utilization rate of bolt materials and achieve light weight design as far as possible, bolts at key positions on an automobile can be screwed until the bolts yield, but the pre-tightening force of the bolts after yielding is attenuated to a certain degree, and the residual clamping force of the bolts after loading is an important index for judging whether the connection performance is reliable or not.
At present, the method for monitoring the residual clamping force in the industry mainly comprises the method for predicting the residual clamping force of the bolt by a pre-buried pressure sensor and a BP neural network. The embedded pressure sensor method can not be realized in the whole vehicle road test and the engine real vehicle rack process. Regarding the BP neural network prediction method, test data are led into a neural network model for training by taking working condition and cycle frequency (service time) as input and taking percentage of residual clamping force as output; the trained neural network model can predict the residual clamping force of the bolt under a specific working condition. The working condition of the whole vehicle road test is carried out on the experimental road, the working condition of the whole vehicle road test cannot be completely consistent with the working condition of the early-stage experiment, and the measurement precision is low when the measurement is carried out on the basis.
Disclosure of Invention
The embodiment of the application provides an ultrasonic measurement method and system for residual clamping force in a bolt plastic area, and aims to solve the problem of low measurement precision in measurement.
In a first aspect, an embodiment of the present application provides a method for ultrasonic measurement of a residual clamping force in a bolt plastic region, where the method includes:
acquiring a standard curve table, wherein the standard curve table comprises sound values of ultrasonic passing through a bolt under different stresses;
acquiring sound time values of ultrasonic waves passing through the bolt in different states; wherein the different states include at least a clamped state assembled to the vehicle, a free state disassembled from the vehicle and annealed;
and determining the residual clamping force of the bolt according to the sound values of the ultrasonic waves passing through the bolt in different states and the standard curve table.
Optionally, a standard curve table is obtained, comprising:
measuring the sound value of ultrasonic waves passing through the bolt under the stress-free state of the bolt;
applying gradually increased stress to the bolt to obtain the sound time value of the ultrasonic wave passing through the bolt under each stress;
and counting different stresses and sound values respectively corresponding to the different stresses to obtain the standard curve table.
Alternatively, in the case of acquiring an acoustic value of ultrasonic waves passing through the bolt in the clamped state, the method includes:
performing a road test on a vehicle in a case where it is determined that the bolt is fitted to the vehicle;
and acquiring a road test result of the vehicle, and acquiring a sound time value of ultrasonic waves passing through the bolt in the clamping state under the condition that the road test result is normal.
Optionally, the bolt is tightened to a yield state when the bolt is fitted to a vehicle.
Optionally, acquiring a sound value of ultrasonic waves passing through the bolt in the clamped state includes:
starting a preset countdown at the moment when the road test is detected to be finished; before the preset countdown is finished, controlling the vehicle to be in a static state;
and acquiring the sound time value of the ultrasonic wave passing through the bolt in the clamping state when the preset countdown is finished.
Optionally, the preset countdown is not less than 24 hours.
Optionally, the temperature of the annealing treatment is 160-200 ℃, and the annealing time is 2-4 hours.
Optionally, in the case of acquiring an acoustic value when an ultrasonic wave passes through the bolt in the free state, the method includes:
after the bolt is detected to be annealed, moving the bolt to room temperature and standing;
and acquiring the sound time value of the ultrasonic wave passing through the bolt in the free state when the temperature of the bolt is detected to be reduced to the preset temperature.
Optionally, determining the residual clamping force of the bolt according to the sound values of the ultrasonic waves passing through the bolt in different states and the standard curve table comprises:
determining the time difference between the sound values of the ultrasonic waves passing through the bolt in different states;
determining two target times adjacent to the time difference from the standard curve table;
determining a residual clamping force of the bolt based on the stresses corresponding to each of the two target times.
A second aspect of embodiments of the present application provides an ultrasonic measurement system for a residual clamping force in a plastic region of a bolt, the system comprising:
the bolt axial force ultrasonic detection module is used for acquiring a standard curve table, wherein the standard curve table comprises sound values of ultrasonic waves passing through the bolt under different stresses;
the bolt pretightening force ultrasonic detection module is used for acquiring the sound time values of the bolts when ultrasonic waves pass through different states; wherein the different states include at least a clamped state assembled to the vehicle, a free state disassembled from the vehicle and annealed;
and the determining module is used for determining the residual clamping force of the bolt according to the sound values of the bolt when ultrasonic waves pass through different states and the standard curve table.
Has the advantages that:
the application provides an ultrasonic measuring method and system applied to assembling residual clamping force in a bolt plastic area, wherein through a bolt axial force ultrasonic detecting module, the sound time value of ultrasonic waves passing through a bolt under each stress in an initial state of the bolt is measured, different stresses and sound time values corresponding to the different stresses are counted, a corresponding relation is established between the stress borne by the bolt and the flight time of the ultrasonic waves, a standard curve table is obtained, then the bolt is assembled on a road test vehicle and subjected to a road test, so that the working condition is simulated, the sound time value of the bolt in a clamping state is detected through a bolt pre-tightening force ultrasonic detecting module, the use working condition of the bolt is fully simulated, and the precision of the sound time value of the ultrasonic waves in the clamping state is effectively improved; and then the bolt is disassembled for annealing treatment, so that residual stress deviation caused by plastic deformation after the bolt path test is eliminated, the precision of the sound time value of the free-state ultrasonic wave is effectively improved, and then the sound time value of the bolt in the free state is detected through the bolt pretightening force ultrasonic wave detection module. The difference value of the two sound values of the clamping state and the free state is obtained through calculation, the difference value is substituted into the standard curve table, the residual clamping force of the bolt can be obtained, and the accuracy of the finally measured residual clamping force is effectively improved.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required to be used in the description of the embodiments of the present application will be briefly described below, and it is obvious that the drawings in the description below are only some embodiments of the present application, and it is obvious for those skilled in the art that other drawings may be obtained according to these drawings without inventive labor.
Fig. 1 is a flowchart of a measurement method according to an embodiment of the present application;
fig. 2 is a block diagram of a measurement system according to an embodiment of the present application.
Detailed Description
The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some, but not all, embodiments of the present application. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
In the related art, the pre-embedded pressure sensor method needs to connect an upper pressure sensor in the structure for monitoring the bolt clamping force in real time, needs to change the connection structure, and cannot be realized in the whole vehicle road test and the engine real vehicle rack process. The BP neural network prediction method needs to collect a large amount of service working conditions of the bolt in the early period, and establishes a corresponding relation between the working conditions and the bolt clamping force on the basis.
In view of this, the present application provides an ultrasonic measurement method for residual clamping force in a bolt plastic region, fig. 1 is a flowchart of the measurement method provided in this embodiment, and referring to fig. 1, the measurement method includes the following steps:
s1: and acquiring a standard curve table, wherein the standard curve table comprises sound values of the bolt passing through the bolt under different stresses.
Wherein, the sound value is the flight time of the ultrasonic wave in the measuring object. When the bolt is measured, different stresses are applied to the bolt, the sound time value of the ultrasonic wave in the bolt can be changed, the sound time value corresponding to the stress can be obtained by continuously changing the stress borne by the bolt, and a corresponding relation is established between the stress borne by the bolt and the flight time of the ultrasonic wave, so that a standard curve table is obtained.
S2: and acquiring sound values of ultrasonic waves passing through the bolts in different states. Wherein the different states include at least a clamped state assembled to the vehicle, a free state disassembled from the vehicle and annealed.
After the bolt is assembled on a vehicle and screwed tightly, the bolt is stressed, the bolt is in a clamping state, and therefore the sound value of ultrasonic waves passing through the bolt can be measured when the bolt is in the clamping state. The bolt can take place plastic deformation under the tight state of clamp, and after finishing measuring, can carry out annealing treatment after dismantling the bolt, eliminate the plastic deformation of bolt to eliminate the internal stress of bolt, make the bolt resume free state, at this moment, can measure the bolt and be in under the free state, the sound duration value of ultrasonic wave through the bolt.
S3: and determining the residual clamping force of the bolt according to the sound values of the ultrasonic waves passing through the bolt in different states and a standard curve table.
After sound values of the bolts in different states are obtained, the difference values between the sound values in different states are obtained through calculation, and then the difference values are substituted into a standard curve table, so that residual clamping force corresponding to the difference values can be obtained.
And measuring the sound time values of the ultrasonic waves passing through the bolt under each stress in the initial state of the bolt, and counting different stresses and sound time values corresponding to the different stresses to obtain a standard curve table. Thereby carry out the way examination after the simulation operating mode, detect the sound duration value when the bolt is in clamping state, the use operating mode of abundant simulation bolt has effectively improved the precision of clamping state survey ultrasonic wave sound duration value. And then the bolt is disassembled for annealing treatment, so that the sound time value difference caused by plastic deformation (internal stress) generated after the bolt path test is eliminated, and then the sound time value of the bolt in a free state is detected, so that the precision of the sound time value of the free state ultrasonic wave is effectively improved. And calculating to obtain the sound time value difference of two sound time values of the clamping state and the free state, and substituting the sound time value difference into the standard curve table to obtain the residual clamping force of the bolt, thereby effectively improving the precision of the finally measured residual clamping force.
Obtaining a standard curve table, comprising: measuring the sound value of ultrasonic waves passing through the bolt under the stress-free state of the bolt; applying gradually increased stress to the bolt to obtain the sound time value of the ultrasonic wave passing through the bolt under each stress; and counting different stresses and sound values respectively corresponding to the different stresses to obtain the standard curve table.
Specifically, when a standard curve table is obtained, firstly, when a bolt is in an initial state, a sound time value of ultrasonic waves in the bolt is obtained and used as a starting point of the standard curve table, then the using working condition of the bolt is simulated, torsional tensile stress is applied to the bolt, the sound time value of the ultrasonic waves in the bolt is measured once when the stress value is increased by one stage, corresponding points are drawn on the standard curve table, the stress value applied to the bolt is continuously increased until the yield strength of the bolt is reached, a series of continuous points are finally obtained, each point corresponds to the stress value and the sound time value corresponding to the stress value, and then the continuous points are drawn into a smooth curve, so that the standard curve table of the bolt is obtained.
In the case of acquiring a sound value when ultrasonic waves pass through the bolt in the clamped state, the method includes: performing a road test on a vehicle in a case where it is determined that the bolt is fitted to the vehicle; and acquiring a road test result of the vehicle, and acquiring a sound time value of ultrasonic waves passing through the bolt in the clamping state under the condition that the road test result is normal.
Specifically, when the sound time values of the ultrasonic waves passing through the bolt in different states are acquired, the sound time values in the bolt clamping state are acquired first. And installing the bolt to a corresponding to-be-tested joint on the road test vehicle, screwing the bolt until the bolt is yielded, enabling the bolt to be in a clamping state, starting to carry out a road test through the road test vehicle, and driving the road test vehicle to simulate the working condition of the bolt under a normal condition.
In the case of acquiring a sound value of an ultrasonic wave passing through the bolt in the clamped state, the method includes: starting a preset countdown at the moment when the road test is detected to be finished; controlling the vehicle to be in a static state before the preset countdown is finished; and acquiring the sound time value of the ultrasonic wave passing through the bolt in the clamping state when the preset countdown is finished.
Under the condition that the road test result is normal, namely the bolt works normally until the road test is finished, presetting countdown to keep the road test vehicle still, in one embodiment, presetting the countdown to be not less than 24 hours, measuring the bolt in the clamping state after the stewing is finished, and obtaining the sound time value t1 of the ultrasonic wave in the bolt in the clamping state.
By carrying out a road test on the bolt, the use working condition of the bolt is fully simulated, and the precision of the sound time value t1 of the ultrasonic wave is effectively improved in the clamping state.
In the case of acquiring a sound value when an ultrasonic wave passes through the bolt in the free state, the method includes: after the bolt is detected to be annealed, moving the bolt to room temperature and standing; and acquiring the sound time value of the ultrasonic wave passing through the bolt in the free state when the temperature of the bolt is detected to be reduced to the preset temperature.
The bolts are removed and stress annealed because the bolts yield after being tightened to yield a certain plastic deformation (internal stress). In one embodiment, the annealing temperature is 160 ℃ to 200 ℃ and the annealing time is 2 hours to 4 hours. Thereby recrystallizing the bolt and relieving the internal stress thereof. In this example, the annealing temperature was 180 ℃ and the annealing time was 3 hours.
In yet another embodiment, after the bolt is detected to be annealed, the bolt is moved to a room temperature and stands still; and acquiring the sound time value of the ultrasonic wave passing through the bolt in the free state when the temperature of the bolt is detected to be reduced to the preset temperature.
In this embodiment, after the annealing is completed, the bolt is allowed to stand at room temperature until the bolt is cooled to a preset temperature, so as to avoid the influence of high temperature on the measurement result.
The bolt is recrystallized through annealing treatment, plastic deformation generated after working condition simulation use is eliminated, internal stress of the bolt is eliminated, and the bolt is enabled to recover a stress-free state, so that sound time value difference caused by the plastic deformation (internal stress) generated after a bolt line test is eliminated, and the precision of sound time value t2 of free-state ultrasonic testing is effectively improved.
Specifically, when determining the residual clamping force of the bolt, the time difference between the sound values of the ultrasonic wave passing through the bolt in different states may be determined; then, two target times adjacent to the time difference are determined from the standard curve table; then, the residual clamping force of the bolt is determined based on the respective stresses of the two target times.
The relation between the ultrasonic propagation speed difference and the stress difference is as follows:
in the formula:
Δ t-sound time difference;
l-bolt effective clamping length;
k-a coefficient related to the elastic constant of the material;
theta-temperature;
c represents the ultrasonic propagation speed of the bolt without stress;
E-Young's modulus of elasticity;
total length of L-bolt;
f-stress.
The relationship between the sound time value and the stress and temperature of the bolt is nonlinear, but according to the above formula, each coefficient in the formula is certain for a specific material, namely, Δ t and Δ θ only correspond to an F value, and the following is obtained according to t1 and t2 obtained by the above method:
Δt＝t1-t2
the acoustic values in this implementation are all measured at room temperature, so the F values are only related to at. Finding out points corresponding to two sound time values adjacent to the left and right of the delta t in the standard curve table, wherein the points corresponding to the two sound time values adjacent to the left and right are two target times, and then obtaining a stress value F corresponding to the delta t according to a curve in the standard curve table, namely the residual clamping force of the bolt.
The embodiment of the present application further provides an ultrasonic measurement system for residual clamping force in a bolt plastic region, fig. 1 is a block diagram of the measurement system provided in this embodiment, and referring to fig. 2, the measurement system includes: the device comprises a bolt axial force ultrasonic detection module 201, a bolt pre-tightening force ultrasonic detection module 202, a determination module 203, a road test vehicle 204 and an annealing box 205.
And the bolt axial force ultrasonic detection module 201 is used for acquiring a standard curve table, wherein the standard curve table comprises sound values of the bolts passing through the bolts under different stresses in an ultrasonic mode.
The bolt pretightening force ultrasonic detection module 202 is used for acquiring the sound time values of the ultrasonic waves passing through the bolts in different states; wherein the different states include at least a clamped state when assembled to the vehicle, a free state when disassembled from the vehicle and annealed.
Gather remaining clamp force through pre-buried pressure sensor, must make the processing change with former connection position to conveniently implant the sensor, compare with, ultrasonic measurement is a nondestructive test technique, through the change of ultrasonic wave flight speed under different stress conditions, can learn the stress level that this bolt was located, make the measurement process more convenient, the principle is simpler.
And the determining module 203 is used for determining the residual clamping force of the bolt according to the sound values of the ultrasonic waves passing through the bolt in different states and the standard curve table.
After the standard curve table is obtained, the values are input into the determining module 203, then the sound time values of the bolts in different states are input into the determining module 203, the difference value is calculated, and then the difference value is substituted into the standard curve table to obtain the residual clamping force.
A road test vehicle 204 for assembling the bolt in a clamped state;
the BP neural network prediction method needs a large number of simulation working condition tests to establish the bolt clamping force state under each working condition, the test cost is high, the working condition of a laboratory cannot be completely consistent with the working condition of an automobile in a road test, and the BP neural network prediction method has great difficulty in industrial practice.
An annealing box 205 for annealing the bolt;
after the bolt is screwed, compacted and yielded, certain plastic deformation can be generated, if the sound time value difference of ultrasonic waves in the bolt is measured in the state, the sound time value difference caused by the plastic deformation (internal stress) cannot be eliminated, so that the measurement result is inaccurate, the bolt is recrystallized, the internal stress is eliminated, and then the sound time value of the ultrasonic waves in the free state is measured, so that the sound time value of the ultrasonic waves in the free state is effectively improved.
Measuring the sound time value of ultrasonic waves passing through the bolt under each stress in the initial state of the bolt through a bolt axial force ultrasonic detection module, counting different stresses and sound time values corresponding to the different stresses to obtain a standard curve table, assembling the bolt on a road test vehicle 204, performing a road test to simulate a working condition, and detecting the sound time value of the bolt in a clamping state through a bolt pre-tightening force ultrasonic detection module; and then the bolt is disassembled to carry out annealing treatment, and then the sound time value of the bolt in a free state is detected through a bolt pretightening force ultrasonic detection module. The standard curve table is input into the determining module 203, the difference value of two sound time values of the clamping state and the free state is obtained through calculation of the determining module 203, and the residual clamping force of the bolt can be obtained by substituting the difference value into the standard curve table. Through the system, the test period is effectively shortened, the cost of applying the system to industrial production is reduced, the principle is simpler, and the accuracy of the finally measured residual clamping force is effectively improved.
Optionally, the bolt axial force ultrasonic detection module 201 may be further configured to perform the following steps: and measuring the sound value of the ultrasonic wave passing through the bolt in the unstressed state of the bolt.
Applying gradually increased stress to the bolt to obtain the sound values of the ultrasonic waves passing through the bolt under each stress;
and counting different stresses and sound values respectively corresponding to the different stresses to obtain a standard curve table.
The output end of the bolt axial force ultrasonic detection module 201 is connected with the determination module 203, the stress value of each stage of the bolt axial force ultrasonic detection module 201 and the ultrasonic sound time value corresponding to the stress value in the test process finally form a standard curve table, then the standard curve table is input into the determination module 203 for subsequent use, and the standard curve table is formed through the bolt axial force ultrasonic detection module 201, so that the precision of the standard curve table is more accurate.
Optionally, the road test vehicle 204 may be further configured to perform the steps of: performing a road test on the vehicle in a case where it is determined that the bolt is fitted to the vehicle; and acquiring a road test result of the vehicle, and acquiring a sound time value of ultrasonic waves passing through the bolt in a clamping state under the condition that the road test result is normal.
The road test is carried out by the road test vehicle 204, the use working condition of the bolt is fully simulated, and the precision of the sound time value of the ultrasonic wave measured in the clamping state is effectively improved.
Optionally, the road test vehicle 204 may be further configured to perform the following steps: when the bolt is assembled to the vehicle, the bolt is tightened to a yield state.
The utilization rate of bolt materials is improved, the lightweight design is achieved as far as possible, and when the sound time value of ultrasonic waves is measured in a clamping state, the bolt in the clamping state is closer to the working condition of actual work.
Optionally, the road test vehicle 204 may be further configured to perform the following steps: starting a preset countdown at the moment when the road test is detected to be finished; and controlling the vehicle to be in a static state before the preset countdown is finished.
And acquiring the sound time value of the ultrasonic wave passing through the bolt in the clamping state when the preset countdown is finished.
The temperature of road test vehicle 204 risees after the road test, gives the bolt with heat transfer, leads to the temperature of bolt to rise, makes road test vehicle 204 cool down through stewing to eliminate the influence of temperature to the bolt internal stress of clamping state, improved the precision of clamping state survey ultrasonic sound time value.
Through measurement and calculation of bolt materials, the temperature of 160-200 ℃ is selected, and the bolt is annealed for 2-4 hours, so that the bolt is recrystallized, plastic deformation generated after working condition simulation use is eliminated, internal stress of the bolt is eliminated, the bolt is enabled to recover a stress-free state, sound time value difference caused by plastic deformation (internal stress) generated after a bolt pass test is eliminated, and sound time value of free state ultrasonic wave measurement is effectively improved.
Optionally, the determining module 203 may be further configured to perform the remaining steps: according to the sound values of ultrasonic waves passing through the bolt in different states and a standard curve table, determining the residual clamping force of the bolt, wherein the method comprises the following steps:
determining the time difference between sound values of ultrasonic waves passing through the bolts in different states;
determining two target times adjacent to the time difference from the standard curve table;
the residual clamping force of the bolt is determined based on the stresses corresponding to each of the two target times.
The standard curve table is stored in the determination module 203 after being input into the determination module 203 from the bolt axial force ultrasonic detection module 201, and when the bolt pre-tightening force ultrasonic detection module 202 inputs the sound time value t1 in the clamping state and the sound time value t2 in the free state, the time difference delta t between t1 and t2 is calculated, and then the time difference delta t is substituted into the standard curve table to calculate the residual clamping force, so that the obtained residual clamping force is more accurate.
It should be noted that, in this specification, each embodiment is described in a progressive manner, and each embodiment focuses on differences from other embodiments, and portions that are the same as and similar to each other in each embodiment may be referred to.
It should also be noted that, in this document, the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Moreover, relational terms such as "first" and "second" are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions or should not be construed as indicating or implying relative importance. Also, the terms "include", "including" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or terminal device including a series of elements includes not only those elements but also other elements not explicitly listed or inherent to such process, method, article, or terminal device. Without further limitation, an element defined by the phrases "comprising one of 8230 \8230;" does not exclude the presence of additional like elements in a process, method, article, or terminal device that comprises the element.
The technical solutions provided in the present application are described in detail above, and specific examples are applied herein to explain the principles and embodiments of the present application, and the descriptions of the above examples are only used to help understanding the present application, and the content of the present specification should not be construed as limiting the present application. While various modifications of the illustrative embodiments and applications will be apparent to those skilled in the art based upon this disclosure, it is not necessary or necessary to exhaustively enumerate all embodiments, and all obvious variations and modifications can be resorted to, falling within the scope of the disclosure.
Claims (10)
1. A method for ultrasonic measurement of residual clamping force in a bolt plastic region, the method comprising:
acquiring a standard curve table, wherein the standard curve table comprises sound values of ultrasonic passing of a bolt under different stresses;
acquiring sound time values of ultrasonic waves passing through the bolt in different states; wherein the different states include at least a clamped state assembled to the vehicle, a free state disassembled from the vehicle and annealed;
and determining the residual clamping force of the bolt according to the sound values of the ultrasonic waves passing through the bolt in different states and the standard curve table.
2. The measurement method according to claim 1, wherein obtaining a standard curve table comprises:
measuring the sound time value of ultrasonic waves passing through the bolt in an unstressed state of the bolt;
applying gradually increased stress to the bolt to obtain the sound time value of the ultrasonic wave passing through the bolt under each stress;
and counting different stresses and sound values respectively corresponding to the different stresses to obtain the standard curve table.
3. The measuring method according to claim 1, wherein in the case of acquiring an acoustic value of ultrasonic waves passing through the bolt in the clamped state, comprising:
performing a road test on a vehicle in a case where it is determined that the bolt is fitted to the vehicle;
and acquiring a road test result of the vehicle, and acquiring a sound time value of the ultrasonic wave passing through the bolt in the clamping state under the condition that the road test result is normal.
4. A method of measuring according to claim 3, wherein the bolt is tightened to a yield condition when the bolt is fitted to a vehicle.
5. The measuring method according to claim 3, wherein, in the case of acquiring an acoustic value of an ultrasonic wave passing through the bolt in the clamped state, comprising:
starting a preset countdown at the moment when the road test is detected to be finished; before the preset countdown is finished, controlling the vehicle to be in a static state;
and acquiring the sound time value of the ultrasonic wave passing through the bolt in the clamping state when the preset countdown is finished.
6. The method of claim 5, wherein the predetermined countdown is not less than 24 hours.
7. The method of claim 1, wherein the annealing is performed at a temperature of 160 ℃ to 200 ℃ for a time of 2 hours to 4 hours.
8. The measuring method according to claim 1, wherein, in the case of acquiring an acoustic value of an ultrasonic wave passing through the bolt in the free state, comprising:
after the bolt is detected to be annealed, moving the bolt to room temperature and standing;
and acquiring the sound time value of the ultrasonic wave passing through the bolt in the free state when the temperature of the bolt is detected to be reduced to the preset temperature.
9. The method of claim 1, wherein determining the residual clamping force of the bolt based on the values of the acoustic time of the ultrasonic waves passing through the bolt in different states and the standard curve table comprises:
determining the time difference between the sound values of the ultrasonic waves passing through the bolt in different states;
determining two target times adjacent to the time difference from the standard curve table;
determining a residual clamping force of the bolt based on the respective stresses for the two target times.
10. An ultrasonic measurement system of residual clamping force in a bolt plastic region, the system comprising:
the bolt axial force ultrasonic detection module is used for acquiring the standard curve table, wherein the standard curve table comprises sound values of ultrasonic passing of the bolt under different stresses;
the bolt pretightening force ultrasonic detection module is used for acquiring the sound time values of the bolts when ultrasonic waves pass through different states; wherein the different states include at least the clamped state when assembled to a vehicle, the free state when disassembled from a vehicle and annealed;
and the determining module is used for determining the residual clamping force of the bolt according to the sound values of the ultrasonic waves passing through the bolt in different states and the standard curve table.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110876279.XA CN115683409A (en) | 2021-07-30 | 2021-07-30 | Ultrasonic measurement method and system for residual clamping force of bolt plastic area |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110876279.XA CN115683409A (en) | 2021-07-30 | 2021-07-30 | Ultrasonic measurement method and system for residual clamping force of bolt plastic area |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN115683409A true CN115683409A (en) | 2023-02-03 |
Family
ID=85060012
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110876279.XA Pending CN115683409A (en) | 2021-07-30 | 2021-07-30 | Ultrasonic measurement method and system for residual clamping force of bolt plastic area |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115683409A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116305665A (en) * | 2023-05-15 | 2023-06-23 | 广东工业大学 | Analysis method and related device for residual stress distribution of cross section of workpiece |
-
2021
- 2021-07-30 CN CN202110876279.XA patent/CN115683409A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116305665A (en) * | 2023-05-15 | 2023-06-23 | 广东工业大学 | Analysis method and related device for residual stress distribution of cross section of workpiece |
| CN116305665B (en) * | 2023-05-15 | 2023-08-11 | 广东工业大学 | Analysis method and related device for residual stress distribution of cross section of workpiece |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US7840362B2 (en) | Method and apparatus for assessing the residual life of a sensor unit | |
| CN103063528B (en) | Method for fast evaluating high temperate member residual service life on spot | |
| CN106482953B (en) | A kind of aeroengine pipeline vibration-testing apparatus and method | |
| CN101477111B (en) | Method for testing tire rubber complex stress condition mechanical performance and its special equipment | |
| CN108627401B (en) | Concrete early-age temperature stress test equipment and method based on torus method | |
| CN108318356B (en) | Method for testing fatigue life curve of finished product level of air conditioner piping | |
| Guo et al. | Tension testing of silicone rubber at high strain rates | |
| CN115683409A (en) | Ultrasonic measurement method and system for residual clamping force of bolt plastic area | |
| CN102507742A (en) | Method for evaluating bonding strength of mechanical composite tube | |
| CN110470738A (en) | Structural Damage Identification based on vibratory response difference than function | |
| Sekine et al. | Structural health monitoring of cracked aircraft panels repaired with bonded patches using fiber Bragg grating sensors | |
| CN103940577B (en) | A kind of appraisal procedure of wind tunnel test balance based on acceleration signal energy | |
| CN101187615A (en) | Method for evaluating fatigue performance of rubber-plastic viscoelastic component | |
| CN113567242B (en) | Method for detecting resistance of reinforced concrete or prestressed concrete beam | |
| CN107702990A (en) | A kind of sound emission extensometer and its test method | |
| CN111122189B (en) | Method for measuring uncertainty of test table position of gas equipment and method for measuring thermal efficiency | |
| CN109357827B (en) | Reciprocating equipment shafting vibration experiment and analysis method | |
| Huang et al. | Measurement of r-values of high strength steels using digital image correlation | |
| CN109187186B (en) | A kind of test method and system of polyethylene effective stress under ideal nondestructive state | |
| CN113626951A (en) | Method for evaluating stress state of variable-force spring hanger | |
| JP3669886B2 (en) | Method for analyzing creep characteristics of resin molded products | |
| KR20020035527A (en) | The Method and Device of the Reliability Test and Decision | |
| CN113777283A (en) | Method for directly measuring concrete stress of dam | |
| US20230266217A1 (en) | Fatigue limit testing method for specimens | |
| JP7396327B2 (en) | Steel pipe workability evaluation method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |