Method and device for determining tightening process parameters by torque angle method

Abstract

The invention provides a torque rotation angle method tightening process parameter determination method and device, and the method comprises the steps: obtaining a plurality of groups of test data, drawing a torque rotation angle curve according to each group of test data, and calculating the change rate of the slope of each torque rotation angle curve according to the test data including torque and rotation angle; calculating the fitting torque of each group of test data according to the change rate of the slope of each torque corner curve; and taking the average value of the fitting torque of the multiple groups of test data as the final fitting torque of the torque angle method. According to the method for determining the tightening process parameters of the torque angle method, the fitting torque of the torque angle method and the angle value in the angle control stage can be accurately calculated through multiple groups of test parameters and a calculation method.

Description

Technical Field

[0001] This invention relates to the field of threaded fastener assembly technology, and in particular to a method and apparatus for determining tightening process parameters using the torque-angle method. Background Technology

[0002] Bolted connections, as a detachable connection method, play a vital role in various types of equipment and have an extremely broad market prospect. With the increasing complexity of advanced equipment structures, the increasingly stringent performance requirements, and the continuous development of automated tightening and testing technologies, higher and newer demands are being placed on the precision of controlling the preload of threaded connections. This has led to the widespread application of the more advanced torque-angle tightening process. This advanced tightening process first tightens the threaded connection to the contact torque through torque control, and then tightens it to the required preload through angle control, effectively avoiding the influence of friction coefficient dispersion on the preload control precision. Therefore, the selection of the contact torque plays a crucial role in the control precision of the tightening process. However, currently, the selection of the contact torque often relies on empirical values, making it impossible to accurately obtain the magnitude of the contact torque, thus hindering the development of the torque-angle tightening process. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a method and device for determining the torque-angle method for tightening process parameters, thereby solving the problem that the current empirical method cannot accurately obtain the magnitude of the fitting torque.

[0004] To address the aforementioned technical problems, this invention provides a method for determining tightening process parameters using the torque-angle method, comprising: acquiring multiple sets of test data; plotting a torque-angle curve based on each set of test data, wherein the test data includes torque and angle; calculating the rate of change of the slope of each torque-angle curve; calculating the contact torque of each set of test data based on the rate of change of the slope of each torque-angle curve; and taking the average of the contact torques of multiple sets of test data as the final contact torque using the torque-angle method.

[0005] Optionally, calculating the fitting torque for each set of test data based on the rate of change of the slope of each torque angle curve includes: searching from the angle of each torque angle curve from small to large, determining whether the absolute value of the rate of change of the slope of the torque angle curve is less than a preset threshold; if so, taking the torque corresponding to the rate of change of the slope that is less than the preset threshold for the second time as the fitting torque for that set of test data.

[0006] Optionally, it also includes: taking the torque corresponding to the rate of change of the slope that is less than a preset threshold for the first time as the initial bonding torque of the set of test data.

[0007] Optionally, the method further includes: using the initial contact torque and the contact torque as the dividing point of the torque angle curve, dividing the torque angle curve into an initial tightening segment, a contact segment, and a stable segment, and calculating the slope of the stable segment; obtaining the preload corresponding to the contact torque of each set of test data, wherein the test data also includes the preload; calculating the angle value of each angle control stage based on the preload corresponding to each set of contact torque, the target value of the preload, and the slope of the stable segment; and calculating the final angle value based on the angle values ​​of multiple angle control stages.

[0008] Alternatively, the slope of the steady segment can be calculated using the following formula:

[0009]

[0010] Among them, K sta T is the slope of the stable section, and T is the tightening torque of the stable section. sta To match the torque, This refers to the turning angle of the stable segment.

[0011] Optionally, the angle value for each group of angle control stages can be calculated using the following formula:

[0012]

[0013] in, F represents the angle value during the angle control phase in the torque-angle method. m F is the target value of the preload. sta K is the preload force corresponding to the set of fitting torques. sta The slope of the stable segment is given.

[0014] Optionally, calculating the final angle value based on the angle values ​​of multiple angle control stages includes: taking the average of the angle values ​​of multiple angle control stages as the final angle value.

[0015] To address the aforementioned technical problems, this invention provides a torque-angle method for determining tightening process parameters, comprising: a test fixture, a bolt to be tested, a connected component, a nut, an electric tightening tool, a torque sensor, an ultrasonic force sensor, and a calculation module. The test fixture includes a first groove, and the bolt to be tested includes a bolt head and a bolt shank. The bolt head is fixed in the first groove, and the bolt shank passes through the connected component. The electric tightening tool is connected to the nut and is used to tighten the nut onto the bolt shank. The ultrasonic force sensor is connected to the bolt head and is used to collect the preload force on the bolt during tightening. The torque sensor is connected to the electric tightening tool and is used to collect the torque during tightening. The calculation module is communicatively connected to the electric tightening tool, the torque sensor, and the ultrasonic force sensor, respectively, and is used to receive the preload force sent by the ultrasonic force sensor, receive the torque sent by the torque sensor, receive the angle during tightening sent by the electric tightening tool, and execute the method described in any one of claims 1 to 7.

[0016] Optionally, the test fixture further includes a first through hole located below the first groove, the ultrasonic force sensor being fixed to the test fixture by a magnetic fixing bracket, and the ultrasonic force sensor being connected to the bolt head through the first through hole.

[0017] Optionally, the device further includes a friction replacement component, wherein the contact surface between the connected component and the nut includes a second groove, and the friction replacement component is located in the second groove.

[0018] Compared with the prior art, the present invention has the following advantages:

[0019] The torque-angle method for determining tightening process parameters of this invention can accurately calculate the contact torque and the angle value during the angle control stage through multiple sets of experimental parameters and calculation methods. The device for determining torque-angle method tightening process parameters of this invention includes an ultrasonic force sensor that contacts the bolt head, which can monitor the preload force on the bolt in real time. Furthermore, the ultrasonic force sensor does not require multiple disassembly and reassembly during testing, making it convenient and quick. The device for determining torque-angle method tightening process parameters of this invention also includes a friction replacement component, which can change the friction coefficient between the connected parts and the nut to simulate different connected parts. Attached Figure Description

[0020] The accompanying drawings are included to provide a further understanding of this application; they are incorporated into and constitute a part of this application. The drawings illustrate embodiments of this application and, together with this specification, serve to explain the principles of the invention. In the drawings:

[0021] Figure 1This is a schematic diagram of a torque-angle method for determining tightening process parameters according to an embodiment of the present invention.

[0022] Figure 2A yes Figure 1 Assembly drawing of some parts.

[0023] Figure 2B yes Figure 1 Assembly drawing of another part.

[0024] Figure 3 This is a flowchart of a method for determining tightening process parameters using the torque-angle method according to an embodiment of the present invention.

[0025] Figure 4 yes Figure 3 A flowchart of an embodiment of step S33.

[0026] Figure 5 yes Figure 3 A flowchart of the torque-angle method for determining tightening process parameters in an optimized embodiment.

[0027] Figure 6 This is a schematic diagram of the torque angle curve according to an embodiment of the present invention. Detailed Implementation

[0028] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are merely some examples or embodiments of this application. For those skilled in the art, these drawings can be applied to other similar scenarios without creative effort. Unless obvious from the context or otherwise specified, the same reference numerals in the drawings represent the same structures or operations.

[0029] As described in the background section, the torque-angle method first tightens the threaded connection to the contact torque using torque control, and then tightens it to the required preload using angle control. This effectively avoids the influence of friction coefficient dispersion on the accuracy of preload control. However, currently, the selection of the contact torque often relies on empirical values, making it impossible to accurately obtain the contact torque magnitude and the angle value during the angle control stage, thus hindering the development of the torque-angle method.

[0030] Figure 1This is a schematic diagram of a torque-angle method tightening process parameter determination device according to an embodiment of the present invention. The torque-angle method tightening process parameter determination device 100 includes a calculation module 1, a test fixture 2, an ultrasonic force sensor 3, a bolt to be tested 4, connected parts 5, 6, and 7, a nut 8, an electric tightening tool 9, and a torque sensor 10. In this embodiment, the connected parts are three-layered, including connected parts 5, 6, and 7. In other embodiments, the connected parts may have other numbers of layers; this application does not limit the number of layers in the connected parts. Figure 2A yes Figure 1 Assembly drawing of some parts. Figure 2B yes Figure 1 Assembly drawings for another part of the components. (For example...) Figure 2A As shown, the bolt 4 under test includes a bolt head 41 and a bolt shank 42. The bolt shank 42 passes through the connected parts 5, 6, and 7. An electric tightening tool (not shown) is connected to a nut 8 and is used to tighten the nut 8 onto the bolt shank 42. Figure 2B As shown, the test fixture 2 includes a first groove A1, in which the bolt head 41 is fixed. The test fixture 2 also includes a first through hole located below the first groove A1. An ultrasonic force sensor 3 is fixed to the test fixture 2 by a magnetic bracket and is connected to the bolt head 41 through the first through hole. The ultrasonic force sensor 3 is used to collect the preload force on the tested bolt 4 during the tightening process.

[0031] like Figure 1 As shown, torque sensor 10 is connected to electric tightening tool 9, and torque sensor 10 is used to collect torque during the tightening process. Calculation module 1 is communicatively connected to electric tightening tool 9, torque sensor 10, and ultrasonic force sensor 3. Calculation module 1 receives the preload force sent by ultrasonic force sensor 3, the torque sent by torque sensor 10, and the rotation angle during the tightening process sent by electric tightening tool 9. It combines the preload force, torque, and rotation angle to form test parameters, and determines the torque-rotation angle tightening process parameters based on the test parameters.

[0032] Optionally, the bolt head 41 is a D-shaped bolt head, and correspondingly, the first groove A1 is a D-shaped groove.

[0033] like Figure 2A As shown, optionally, the torque-angle method tightening process parameter determining device 100 further includes a friction replacement component 11, and the connected component 7 includes a second groove A2. The shape of the second groove A2 matches the friction replacement component 11. The friction replacement component 11 is located in the second groove A2. By replacing the friction replacement component 11, the coefficient of friction between the connected component 7 and the nut 8 can be changed.

[0034] Optionally, the torque-angle method tightening process parameter determination device 100 also includes a test platform 12, on which the test fixture 2 is fixed.

[0035] The torque-angle method tightening process parameter determination device of the present invention includes an ultrasonic force sensor that fits against the bolt head, which can monitor the preload force on the bolt in real time. Furthermore, the ultrasonic force sensor does not require multiple disassembly and reassembly during testing, making it convenient and quick. The torque-angle method tightening process parameter determination device of the present invention also includes a friction replacement component, which can change the friction coefficient between the connected parts and the nut to simulate different connected parts.

[0036] To facilitate understanding of the torque-angle method tightening process parameter determination device of this application, the test procedure of the torque-angle method tightening process parameter determination device is described below:

[0037] (1) Fix the test fixture 2 on the test platform 12 to ensure that the test fixture 2 remains stationary during the test.

[0038] (2) The bolt 4 to be tested is passed through the three connected parts 5, 6, 7 and the simulated replacement part 11, and the D-shaped head of the bolt is placed in the first groove and fixed on the test fixture 2; the ultrasonic preload sensor 3 is attached to the bolt head 41, and the ultrasonic preload sensor 3 is fixed on the test fixture 2 using a magnetic suction bracket.

[0039] (3) Apply grease to the first three turns of the thread of the bolt 4 to be tested, and install the nut 8 on the bolt 4.

[0040] (4) Select a suitable size socket connecting nut 8 with the electric tightening tool 9, and tighten the nut 8 to 30% of the maximum tightening torque of the bolt of this specification using the electric tightening tool 9, and then stop applying torque. Rotate the nut 8 one full turn using the electric tightening tool 9, and repeat this process once.

[0041] (5) Turn on the ultrasonic force sensor 3 and torque sensor 10 to start collecting data. Use the torque method for control. Use the electric tightening tool 9 to load the bolt to 70% of the maximum tightening torque of this specification. Record the output torque, rotation angle and preload data during the tightening process.

[0042] (6) Conduct 30 sets of repeated tests and measure the torque, rotation angle and preload data output during the tightening process in each of the 30 sets.

[0043] (7) The calculation module executes the torque-angle method to determine the tightening process parameters, and obtains the contact torque and the angle value of the angle control stage.

[0044] Figure 3 This is a flowchart of a method for determining tightening process parameters using the torque-angle method according to an embodiment of the present invention. Figure 3As shown, the torque-angle method for determining tightening process parameters 300 includes:

[0045] Step S31: Obtain multiple sets of test data, and plot a torque-angle curve based on each set of test data. The test data includes torque and angle.

[0046] Step S32: Calculate the rate of change of the slope of each torque angle curve.

[0047] Alternatively, the second derivative of each torque angle curve can be used as the rate of change of the slope of each torque angle curve by taking the second derivative.

[0048] Step S33: Calculate the fitting torque for each set of test data based on the rate of change of the slope of each torque angle curve.

[0049] Figure 4 yes Figure 3 A flowchart of an embodiment of step S33. (See attached flowchart.) Figure 4 As shown, step S33 includes:

[0050] Step S331: Search from the smallest to the largest angle of each torque angle curve, and determine whether the absolute value of the rate of change of the slope of the torque angle curve is less than a preset threshold. If yes, proceed to step S332; otherwise, continue the search.

[0051] Step S332: The torque corresponding to the rate of change of the slope that is less than the preset threshold for the first time is taken as the initial bonding torque of the test data.

[0052] Step S333: The torque corresponding to the rate of change of the slope that is less than the preset threshold for the second time is taken as the fitting torque of this set of test data.

[0053] Steps S331 to S333 can be understood as the torque corresponding to the first time the rate of change of the slope approaches 0, which is the initial contact torque T. co (Non-self-locking nut T) co =0), the torque corresponding to the second time it approaches 0 is the perfect fit torque T. sta Among them, the perfectly matched torque T sta This refers to the contact torque for each bolt and nut pair.

[0054] Step S34: The average value of the bonding torque of multiple sets of test data is taken as the final bonding torque of the torque angle method.

[0055] Taking 30 sets of test data as an example, the contact torque of the bolts and nuts in the 30 sets was calculated respectively, and the average value was taken as the contact torque of this batch of bolts under the torque-angle method.

[0056] Figure 5 yes Figure 3A flowchart illustrating the method for determining tightening process parameters using the torque-angle method in the optimized embodiment. (See flowchart for example.) Figure 5 As shown, the method 500 for determining tightening process parameters using the torque angle method also includes:

[0057] Step S35: Using the initial contact torque and the contact torque as the dividing points of the torque angle curve, the torque angle curve is divided into the initial tightening segment, the contact segment, and the stable segment, and the slope of the stable segment is calculated.

[0058] Figure 6 This is a schematic diagram of the torque-angle curve according to an embodiment of the present invention. Figure 6 As shown, the torque-angle curve is divided into an initial tightening segment S1, a contact segment S2, and a stable segment S3. The boundary between the initial segment S1 and the contact segment S2 is the initial contact torque, and the boundary between the contact segment S2 and the stable segment S3 is the contact torque. Optionally, the slope K of the stable segment S3 is calculated using the following formula. sta :

[0059]

[0060] Among them, T sta To match the torque, T is the tightening torque in the stable section. Let T be the angle of rotation in the stable segment, where T and It can be read from the test parameters.

[0061] Step S36: Obtain the preload corresponding to the fitting torque for each set of test data. The test data also includes the preload.

[0062] Step S37: Calculate the angle value of each angle control stage based on the preload, target preload value, and slope of the stable section corresponding to each set of contact torque.

[0063] Alternatively, the angle value in the angle stage of the torque-angle method can be calculated using the following formula:

[0064]

[0065] in, F represents the angle value during the angle control phase in the torque-angle method. m F is the target value of the preload. sta K is the preload force corresponding to the set of fitting torques. sta The slope of the stable segment is given.

[0066] Step S38: Calculate the final angle value based on the angle values ​​from multiple angle control stages.

[0067] Optionally, the average of the angle values ​​from multiple angle control stages is taken as the final angle value. Continuing with 30 sets of test data as an example, the angle values ​​for each of the 30 bolt angle control stages are calculated, and their average value is taken as the angle value for the angle control stage under the torque-angle method for this batch of bolts.

[0068] In some embodiments, the minimum and maximum angle values ​​are taken from the angle values ​​of multiple angle control stages, and the average of the minimum and maximum angle values ​​is taken as the final angle value.

[0069] The torque-angle method for determining tightening process parameters of the present invention can accurately calculate the magnitude of the contact torque and the angle value during the angle control stage by using multiple sets of experimental parameters and calculation methods.

[0070] The basic concepts have been described above. Obviously, for those skilled in the art, the above disclosure is merely illustrative and does not constitute a limitation of this application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements, and corrections to this application. Such modifications, improvements, and corrections are suggested in this application, and therefore remain within the spirit and scope of the exemplary embodiments of this application.

[0071] Furthermore, this application uses specific terms to describe embodiments of the application. For example, "an embodiment," "one embodiment," and / or "some embodiments" refer to a particular feature, structure, or characteristic related to at least one embodiment of the application. Therefore, it should be emphasized and noted that "an embodiment," "one embodiment," or "an alternative embodiment" mentioned twice or more in different locations in this specification do not necessarily refer to the same embodiment. In addition, certain features, structures, or characteristics in one or more embodiments of the application can be appropriately combined.

[0072] Some aspects of this application can be executed entirely by hardware, entirely by software (including firmware, resident software, microcode, etc.), or by a combination of hardware and software. The aforementioned hardware or software may be referred to as a "data block," "module," "engine," "unit," "component," or "system." The processor may be one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DAPDs), programmable logic devices (PLDs), field-programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, or combinations thereof. Furthermore, aspects of this application may manifest as computer products residing in one or more computer-readable media, including computer-readable program code. For example, computer-readable media may include, but are not limited to, magnetic storage devices (e.g., hard disks, floppy disks, magnetic tapes, etc.), optical discs (e.g., compressed CDs, digital multifunction DVDs, etc.), smart cards, and flash memory devices (e.g., cards, sticks, key drives, etc.).

[0073] Similarly, it should be noted that, in order to simplify the description of the present application and thus aid in the understanding of one or more embodiments of the invention, the foregoing description of the embodiments of the present application sometimes combines multiple features into a single embodiment, drawing, or description thereof. However, this disclosure method does not imply that the subject matter of the application requires more features than those mentioned in the claims. In fact, the embodiments contain fewer features than all the features of the single embodiments disclosed above.

[0074] As indicated in this application and claims, unless the context clearly indicates otherwise, the words "a," "an," "an," and / or "the" are not specifically singular and may include plural forms. Generally speaking, the terms "comprising" and "including" only indicate the inclusion of explicitly identified steps and elements, which do not constitute an exclusive list, and the method or apparatus may also include other steps or elements.

[0075] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of this application. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.

[0076] In the description of this application, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is usually based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this application and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this application; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0077] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0078] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, these terms have no special meaning and therefore should not be construed as limiting the scope of protection of this application. In addition, although the terminology used in this application is selected from commonly known and used terms, some terms mentioned in this application's specification may have been chosen by the applicant according to his or her judgment, and their detailed meanings are explained in the relevant sections of this description. Moreover, this application should be understood not only through the actual terms used, but also through the meaning implied by each term.

[0079] Flowcharts are used in this application to illustrate the operations performed by the system according to embodiments of this application. It should be understood that the preceding or following operations are not necessarily performed in exact order. Instead, various steps can be processed in reverse order or simultaneously. Furthermore, other operations may be added to these processes, or one or more steps may be removed from these processes.

[0080] Although this application has been described with reference to specific embodiments, those skilled in the art should recognize that the above embodiments are only used to illustrate this application, and various equivalent changes or substitutions can be made without departing from the spirit of this application. Therefore, any changes or modifications to the above embodiments within the essential spirit of this application will fall within the scope of the claims of this application.

Claims

1. A method for determining tightening process parameters using the torque-angle method, characterized in that, include: Acquire multiple sets of test data, and plot a torque-angle curve based on each set of test data, wherein each set of test data includes torque and angle; Calculate the rate of change of the slope of each torque angle curve; The fitting torque for each set of test data is calculated based on the rate of change of the slope of each torque angle curve; The average bonding torque of multiple sets of test data is taken as the final bonding torque of the torque angle method.

2. The method for determining tightening process parameters as described in claim 1, characterized in that, The contact torque for each set of test data is calculated based on the rate of change of the slope of each torque angle curve, including: Search from the smallest to the largest angle of each torque angle curve, and determine whether the absolute value of the rate of change of the slope of the torque angle curve is less than a preset threshold. If so, take the torque corresponding to the rate of change of the slope that is less than the preset threshold for the second time as the fitting torque of the test data.

3. The method for determining tightening process parameters as described in claim 1, characterized in that, Also includes: The torque corresponding to the rate of change of the slope that is less than the preset threshold for the first time is taken as the initial fitting torque of this set of test data.

4. The method for determining tightening process parameters as described in claim 3, characterized in that, Also includes: The initial contact torque and the contact torque are used as the dividing point of the torque angle curve. The torque angle curve is divided into an initial tightening segment, a contact segment, and a stable segment. The slope of the stable segment is calculated. Obtain the preload force corresponding to the fitting torque for each set of test data, and the test data also includes the preload force; The angle value of each angle control stage is calculated based on the preload corresponding to each set of contact torque, the target value of the preload, and the slope of the stable section. The final angle value is calculated based on the angle values ​​from multiple angle control stages.

5. The method for determining tightening process parameters as described in claim 3, characterized in that, The slope of the steady segment is calculated using the following formula: Among them, K sta T is the slope of the stable section, and T is the tightening torque of the stable section. sta To match the torque, This refers to the turning angle of the stable segment.

6. The method for determining tightening process parameters as described in claim 4, characterized in that, The angle value for each angle control phase is calculated using the following formula: in, F represents the angle value during the angle control phase in the torque-angle method. m F is the target value of the preload. sta K is the preload force corresponding to the set of fitting torques. sta The slope of the stable segment is given.

7. The method for determining tightening process parameters as described in claim 4, characterized in that, Calculating the final angle value based on the angle values ​​of multiple angle control stages includes: taking the average of the angle values ​​of multiple angle control stages as the final angle value.

8. A device for determining tightening process parameters using the torque-angle method, characterized in that, include: The test fixture includes a test bolt, a connected component, a nut, an electric tightening tool, a torque sensor, an ultrasonic force sensor, and a calculation module. The test fixture includes a first groove, and the test bolt includes a bolt head and a bolt shank. The bolt head is fixed in the first groove, the bolt shank passes through the connected component, and the electric tightening tool is connected to the nut. The electric tightening tool is used to tighten the nut onto the bolt shank. The ultrasonic force sensor is connected to the bolt head and is used to collect the preload force on the bolt being tested during the tightening process. The torque sensor is connected to the electric tightening tool and is used to collect the torque during the tightening process; The calculation module is communicatively connected to the electric tightening tool, the torque sensor, and the ultrasonic force sensor, respectively, and is used to receive the preload force sent by the ultrasonic force sensor, receive the torque sent by the torque sensor, receive the rotation angle during the tightening process sent by the electric tightening tool, and execute the method as described in any one of claims 1 to 7.

9. The tightening process parameter determining device as described in claim 8, characterized in that, The test fixture also includes a first through hole located below the first groove. The ultrasonic force sensor is fixed to the test fixture by a magnetic fixing bracket and is connected to the bolt head through the first through hole.

10. The tightening process parameter determining device as described in claim 8, characterized in that, Also includes: A friction replacement part, wherein the surface of the connected part that contacts the nut includes a second groove, and the friction replacement part is located in the second groove.

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