Bolt type selection method, device and equipment and storage medium

Abstract

The invention discloses a bolt type selection method and device, equipment and a storage medium, and relates to the technical field of machine manufacturing. A reference axial force is obtained according to the relevant part parameters and the driving torque, axial force attenuation analysis is conducted on the reference axial force, a target axial force is obtained, a pre-selection type is determined, and the maximum axial force and the minimum axial force of the pre-selection type are obtained based on the pre-selection type; when the minimum axial force is greater than the preset axial force of the rotation torque, obtaining a verification parameter according to the maximum axial force and the minimum axial force; when the verification parameters meet the preset parameter requirements, the pre-selected type is used as a target bolt type; according to the method, the due minimum axial force of the bolt is determined through the associated parameters of the bolt, so that the bolt is pre-selected, the bolt model selection meeting the requirement is obtained based on pre-selected bolt verification, the reliability of bolt design is effectively improved, the bolt type better meeting the standard is obtained, and the situation that an oil pump cannot work normally due to the fact that bolt type selection is not accurate enough is avoided.

Description

Technical Field

[0001] The present application relates to the field of mechanical manufacturing technology, and in particular to a bolt selection method, device, equipment and storage medium. Background Art

[0002] The common gasoline engine oil pump is driven by a chain or belt and the crankshaft, that is, by applying appropriate compression force to the oil pump sprocket fixing bolts, the oil pump drive sprocket and the oil pump drive shaft are tightened. When the engine is running, the static friction between the joint surfaces of the above parts is ensured to prevent relative rotation, and the oil pump is driven to operate and supply oil to the engine lubrication system. The oil pump sprocket fixing bolts must have sufficient strength and hardness to overcome the above-mentioned alternating output torque load, otherwise the sprocket is prone to loosening and the oil pump will not work, resulting in poor engine lubrication and wear of moving parts due to the inability of the oil pump to work properly. Therefore, the oil pump sprocket fixing bolts are key parts of the engine lubrication system.

[0003] However, for a long time, the design and development of the oil pump sprocket fixing bolts have not received enough attention. They have been developed and applied as universal standard parts. A forward development process based on the assembly boundary and external load of the engine has not been established to consider the tightening and transmission torque requirements of the oil pump and to select and verify the bolts. During the design process, the actual production deviation of the key parameters of the bolts cannot be considered, resulting in safety risks for the bolts. The design of some torsional vibration damper fixing bolts refers to the VDI-2230 standard, but this standard has high requirements on the designer's professional ability in mechanics, mathematics, etc., and design errors are prone to occur and are difficult to explore. The calculation process is relatively complicated, and the development efficiency is low, which seriously affects the development progress of parts.

[0004] The above contents are only used to assist in understanding the technical solution of the present application and do not constitute an admission that the above contents are prior art. Summary of the invention

[0005] The main purpose of the present application is to provide a bolt selection method, device, equipment and storage medium, aiming to solve the technical problem in the prior art that in the process of selecting fixing bolts for chain-driven oil pumps, the bolt type selection is not accurate enough, resulting in the oil pump not being able to work normally.

[0006] To achieve the above purpose, the present application proposes a bolt selection method, which includes: Get the associated part parameters and driving torque of the bolt; Obtain a reference axial force according to the associated part parameters and the driving torque, and perform axial force attenuation analysis on the reference axial force to obtain a target axial force; Obtain a preselected type according to the target axial force, and obtain a maximum axial force and a minimum axial force of the preselected type based on the preselected type; When the minimum anti-slip torque corresponding to the minimum axial force is greater than the rotational torque, obtaining a verification parameter according to the maximum axial force and the minimum axial force; When the verification parameters meet the preset parameter requirements, the pre-selected type is used as the target bolt type.

[0007] In one embodiment, the part parameters include the contact inner diameter and the contact outer diameter of each engagement surface with the bolt; the step of obtaining the reference axial force according to the associated part parameters and the driving torque, and performing axial force attenuation analysis on the reference axial force to obtain the target axial force includes: Obtaining an equivalent contact radius of each bonding surface according to the contact inner diameter and the contact outer diameter; Obtaining a reference axial force according to the driving torque and the equivalent contact radius of each of the combined surfaces; An axial force attenuation analysis is performed on the reference axial force to obtain a target axial force.

[0008] In one embodiment, obtaining the reference axial force according to the driving torque and the equivalent contact radius of each of the joint surfaces includes: The smallest equivalent contact radius among the equivalent contact radii of each bonding surface is used as a reference equivalent contact radius; A reference axial force is obtained according to the reference equivalent contact radius and the driving torque.

[0009] In one embodiment, obtaining a pre-selected type according to the target axial force, and obtaining a maximum axial force and a minimum axial force of the pre-selected type based on the pre-selected type, includes: Using the target axial force as a minimum threshold of the tightening force; Determining a yield strength range, a friction coefficient range, bolt specifications and dimensions based on the minimum tightening force threshold; A pre-selection is obtained based on the yield strength range, the friction coefficient range, and the bolt specification and size; Based on the pre-selection, the maximum axial force and the minimum axial force of the pre-selection are obtained.

[0010] In one embodiment, obtaining the maximum axial force and the minimum axial force of the pre-selected type based on the pre-selected type includes: Obtaining bolt parameters, and constructing a bolt preload model according to the bolt parameters; Based on the yield strength range, a minimum yield strength and a maximum yield strength are obtained, and based on the friction coefficient range, a maximum friction coefficient and a minimum friction coefficient are obtained; Obtaining a minimum axial force through the bolt preload model based on the minimum yield strength and the maximum friction coefficient; The maximum axial force is obtained through the bolt preload model based on the maximum yield strength and the minimum friction coefficient.

[0011] In one embodiment, the verification parameters include safety parameters, stress parameters, and thread strength parameters; When the minimum anti-slip torque corresponding to the minimum axial force is greater than the rotational torque, obtaining the verification parameter according to the maximum axial force and the minimum axial force includes: When the minimum axial force is greater than a preset axial force of the rotational torque, a safety parameter is obtained according to the minimum axial force and the reference axial force; Obtaining the areas of each contact surface according to the associated part parameters, and obtaining stress parameters according to the areas of each contact surface and the maximum axial force; Thread parameters are obtained, and thread strength parameters are obtained according to the thread parameters and the maximum axial force.

[0012] The internal thread shear equivalent cross-sectional area is obtained according to the associated part parameters, the internal thread allowable shear force is obtained according to the internal thread shear equivalent cross-sectional area, and the thread strength parameter is obtained according to the and the maximum axial forces.

[0013] In one embodiment, the acquiring of thread parameters, and obtaining thread strength parameters according to the thread parameters and the maximum axial force, includes: Obtaining thread parameters, and obtaining the internal thread shear equivalent cross-sectional area according to the thread parameters; The allowable shear force of the internal thread is obtained according to the equivalent shear cross-sectional area of ​​the internal thread, and the thread strength parameter is obtained according to the and the maximum axial forces.

[0014] In addition, to achieve the above purpose, the present application also proposes a bolt selection device, the bolt selection device comprising: A parameter acquisition module is used to obtain the associated part parameters and driving torque of the bolt; An axial force analysis module, used for obtaining a reference axial force according to the associated part parameters and the driving torque, performing an axial force attenuation analysis on the reference axial force, and obtaining a target axial force; The axial force analysis module is further used to obtain a pre-selected type according to the target axial force, and obtain a maximum axial force and a minimum axial force of the pre-selected type based on the pre-selected type; A selection and verification module, configured to obtain a verification parameter according to the maximum axial force and the minimum axial force when the minimum anti-slip torque corresponding to the minimum axial force is greater than the rotational torque; The selection and verification module is also used to use the pre-selection as the target bolt selection when the verification parameters meet the preset parameter requirements.

[0015] In addition, to achieve the above objectives, the present application also proposes a bolt selection device, which includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program is configured to implement the steps of the bolt selection method described above.

[0016] In addition, to achieve the above-mentioned purpose, the present application also proposes a storage medium, which is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, the steps of the bolt selection method described above are implemented.

[0017] In addition, to achieve the above-mentioned purpose, the present application also provides a computer program product, which includes a computer program, and when the computer program is executed by a processor, the steps of the bolt selection method described above are implemented.

[0018] One or more technical solutions proposed in this application have at least the following technical effects: The minimum axial force that the bolt should have is determined by the engine torque and the associated parameters of the bolt under various working conditions, and the bolt is pre-selected based on the minimum axial force. The bolt is checked based on the pre-selected type to obtain a bolt selection that meets the requirements, which effectively improves the reliability of the bolt design, thereby obtaining a bolt type that is more in line with the standard and avoiding the oil pump from not working properly due to inaccurate bolt type selection. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0020] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0021] Figure 1 A schematic diagram of a process flow provided for the first embodiment of the bolt selection method of the present application; Figure 2 A schematic diagram of the assembly of the fixing bolts of the driven wheel of the oil pump provided in the first embodiment of the bolt selection method of the present application; Figure 3 A schematic diagram of the assembly of the oil pump sprocket system provided in Embodiment 1 of the bolt selection method of the present application; Figure 4 A schematic diagram of a process for selecting bolts for fixing the sprocket of an oil pump provided in Embodiment 1 of the bolt selection method of the present application; Figure 5A schematic diagram of a process flow provided for Embodiment 2 of the bolt selection method of the present application; Figure 6 This is a schematic diagram of the module structure of the bolt selection device according to an embodiment of the present application; Figure 7 Schematic diagram of the equipment structure of the hardware operating environment involved in the bolt selection method in the embodiment of the present application. DETAILED DESCRIPTION

[0022] It should be understood that the specific embodiments described herein are only used to explain the technical solutions of the present application and are not used to limit the present application.

[0023] In order to better understand the technical solution of the present application, a detailed description will be given below in conjunction with the accompanying drawings and specific implementation methods.

[0024] The main solutions of the embodiments of this application are: The associated part parameters of the bolt are obtained, and the reference anti-slip torque is obtained according to the associated part parameters; the reference axial force is obtained according to the reference slip torque, and the axial force attenuation analysis is performed on the reference axial force to obtain the target axial force; the pre-selection is obtained according to the target axial force, and the maximum axial force and the minimum axial force of the pre-selected type are obtained based on the pre-selection; when the minimum axial force is greater than the preset axial force of the rotational torque, the verification parameters are obtained according to the maximum axial force and the minimum axial force; when the verification parameters meet the preset parameter requirements, the pre-selection is selected as the target bolt.

[0025] In this embodiment, for ease of description, the following description is made with the bolt selection device being the execution subject.

[0026] Since the common gasoline engine oil pump in the prior art is driven by a chain or belt and the crankshaft, that is, by applying appropriate compression force to the oil pump sprocket fixing bolts, the oil pump drive sprocket and the oil pump drive shaft are tightened. When the engine is running, the static friction between the joint surfaces of the above parts is ensured to ensure that there is no relative rotation, and the oil pump is driven to operate to supply oil to the engine lubrication system. The oil pump sprocket fixing bolts must have sufficient strength and hardness to overcome the above-mentioned alternating output torque load, otherwise the sprocket is prone to loosening and the oil pump does not work, resulting in poor engine lubrication due to the oil pump not being able to work properly, wear of moving parts and other faults. Therefore, the oil pump sprocket fixing bolts are key parts of the engine lubrication system.

[0027] However, for a long time, the design and development of the oil pump sprocket fixing bolts have not received enough attention. They have been developed and applied as universal standard parts. A forward development process based on the assembly boundary and external load of the engine has not been established to consider the tightening and transmission torque requirements of the oil pump and to select and verify the bolts. During the design process, the actual production deviation of the key parameters of the bolts cannot be considered, resulting in safety risks for the bolts. The design of some torsional vibration damper fixing bolts refers to the VDI-2230 standard, but this standard has high requirements on the designer's professional ability in mechanics, mathematics, etc., and design errors are prone to occur and are difficult to explore. The calculation process is relatively complicated, and the development efficiency is low, which seriously affects the development progress of parts.

[0028] The present application provides a solution, which determines the minimum axial force that the bolt should have by the engine torque and the associated parameters of the bolt under various working conditions, obtains a pre-selected bolt based on the minimum axial force, and performs bolt verification based on the pre-selected bolt to obtain a bolt selection that meets the requirements, thereby effectively improving the reliability of the bolt design, thereby obtaining a bolt type that meets the standards and avoiding the oil pump from not working properly due to inaccurate selection of the bolt type.

[0029] It can be seen from the above embodiments that the present application discloses a bolt selection method, device, equipment and storage medium, which relates to the field of mechanical manufacturing technology, and discloses: obtaining the associated part parameters of the bolt, and obtaining a reference anti-slip torque according to the associated part parameters; obtaining a reference axial force according to the reference slip torque, performing axial force attenuation analysis on the reference axial force, and obtaining a target axial force; obtaining a pre-selection according to the target axial force, and obtaining the maximum axial force and minimum axial force of the pre-selected type based on the pre-selection; when the minimum axial force is greater than the preset axial force of the rotational torque, obtaining a verification parameter according to the maximum axial force and the minimum axial force; when the verification parameter meets the preset parameter requirements, the pre-selection is used as the target bolt selection; the method determines the minimum axial force that the bolt should have by the engine torque and the associated parameters of the bolt under various working conditions, obtains the bolt pre-selection based on the minimum axial force, and performs bolt verification based on the pre-selection to obtain a bolt selection that meets the requirements, thereby effectively improving the reliability of the bolt design, thereby obtaining a bolt type that meets the standard more, and avoiding the inaccurate selection of the bolt type that causes the oil pump to fail to work properly.

[0030] It should be noted that the execution subject of this embodiment can be a computing service device with data processing, network communication and program running functions, such as a tablet computer, a personal computer, a mobile phone, etc., or an electronic device capable of realizing the above functions, a bolt selection device, etc. The following takes the bolt selection device as an example to illustrate this embodiment and the following embodiments.

[0031] Based on this, the embodiment of the present application provides a bolt selection method, referring to Figure 1 , Figure 1This is a flow chart of the first embodiment of the bolt selection method of the present application.

[0032] In this embodiment, the bolt selection method includes steps S10 to S40: Step S10, obtaining the associated part parameters and driving torque of the bolt.

[0033] It is understandable that the bolt-related part parameters may be the outer diameter and inner diameter of the mating surfaces of the parts of the oil pump sprocket fixing bolt connection system.

[0034] It is understandable that the driving torque may be the oil pump driving torque corresponding to the maximum oil pressure and maximum flow of the oil pump under different vehicle operating conditions.

[0035] It is understood that in a chain-driven oil pump system, the oil pump driving torque refers to the amount of torque transmitted to the oil pump to drive it to work. This torque is the energy obtained by the engine from the crankshaft through the chain and sprocket drive system, and is converted into the torque required for the oil pump to rotate so that the oil pump can overcome internal resistance, establish the necessary oil pressure, and pump oil to various lubrication parts of the engine.

[0036] Step S20, obtaining a reference axial force according to the associated part parameters and the driving torque, performing axial force attenuation analysis on the reference axial force, and obtaining a target axial force.

[0037] It should be noted that the reference axial force can be the axial force required for the fixing bolts of the preset torsional vibration damper under the limit state, and can also be understood as determining the contact area based on the parameters of the associated parts. If the minimum force that satisfies the driving torque based on the contact area is used as the reference axial force.

[0038] It is understandable that the target axial force may decay during the tightening process due to various reasons (such as preload loss, vibration, fatigue strength, etc.). The decay of the axial force will lead to a decrease in the tightening force, resulting in a decline in the bolt tightening ability and a series of other problems.

[0039] It should be noted that axial force attenuation can be a loss of preload - over time and as the engine runs, the preload in the bolted connection may gradually decay. This is due to a variety of factors, including creep of the bolt material, relaxation (especially at high temperatures), and reduced friction between the bolt and the connected parts. The attenuation of the preload will directly affect the bolt's ability to resist slippage and the stability of the connection, which may lead to loose fixation, leakage or structural failure.

[0040] It may also be due to vibration - the continuous vibration generated during engine operation will cause micro-motion wear at the bolt connection and accelerate the attenuation of the preload force, especially under high-frequency vibration conditions, this effect is more significant.

[0041] It could also be fatigue strength - bolts will fatigue under repeated loads, especially when subjected to alternating stress. The attenuation of axial force may cause the bolt to reach the fatigue limit prematurely, causing the bolt to break, which is a serious safety hazard.

[0042] It should be understood that shaft force attenuation may lead to reduced sealing reliability - the sealing of the oil pump depends on the tightness of the bolt connection. Shaft force attenuation may lead to reduced sealing performance, causing oil leakage, affecting the lubrication effect and operating efficiency of the engine. It should be noted that, considering the attenuation of axial force, designers will add a certain safety margin in the initial design to ensure that even when the preload force decreases, the bolts can still maintain sufficient tightening force to ensure the reliability and safety of the entire system; therefore, when designing, engineers need to compensate and control the attenuation of axial force by reasonably selecting bolt materials, specifications, preload force, and possibly taking additional anti-loosening measures (such as using anti-loosening washers, locking nuts, chemical adhesives, etc.) to ensure that the oil pump fixing bolts can maintain sufficient functionality and safety throughout their service life.

[0043] In a feasible implementation, step S20 may include steps A21 to A23: Step A21, obtaining the equivalent contact radius of each bonding surface according to the contact inner diameter and the contact outer diameter.

[0044] It should be noted that the bolt-related part parameters can be the outer diameter and inner diameter of the joint surface of each part of the oil pump sprocket fixing bolt connection system. For the assembly diagram of the oil pump driven wheel fixing bolt, please refer to Figure 2 In the figure, when the crankshaft 5 rotates, an appropriate clamping force is applied to the oil pump fixing bolt to ensure that under the limit state, the fixing bolt gasket 1-1, the oil pump driven wheel 2 and the oil pump body 4 do not slide relative to each other, and the contact outer diameter R of each joint surface o And inner diameter R i , R ei Represents the equivalent contact radius of the ith bonding surface. Figure 2 , the equivalent contact radius of each bonding surface can refer to the following formula:

[0045] Step A22, obtaining a reference axial force according to the driving torque and the equivalent contact radius of each joint surface.

[0046] It should be noted that the reference axial force is obtained according to the driving torque and the equivalent contact radius of each joint surface, including: taking the smallest equivalent contact radius among the equivalent contact radius of each joint surface as the reference equivalent contact radius; obtaining the reference axial force according to the reference equivalent contact radius and the driving torque. It can be understood that the bolt selection method described in this embodiment can be applied to the selection of chain-driven oil pump fixing bolts. For the assembly diagram of the oil pump sprocket system, please refer to Figure 3 In the figure, 1 is the fixing bolt of the driven wheel of the oil pump, 1-1 is the bolt gasket, 2 is the driven wheel of the oil pump, 3 is the driving wheel of the oil pump, 4 is the oil pump, 5 is the crankshaft, and 6 is the transmission chain.

[0047] It should be understood that based on Figure 3 It can be seen that the oil pump fixing bolt 1 is mainly used to fasten the oil pump driven wheel 2. The oil pump driven wheel 2 is connected to the oil pump driving wheel 3 on the crankshaft 3 through a chain. The rotation of the crankshaft during the power stroke of the engine drives the oil pump driven wheel to rotate, thereby driving the oil pump 4 to work. The static friction between the head of the oil pump fixing bolt and the upper surface of its gasket, the bolt gasket and the upper surface of the oil pump driven wheel, and the oil pump driven wheel and the oil pump body transmits the driving torque through the joint surface. By applying appropriate and uniform pre-tightening force to the oil pump fixing bolt, it is ensured that the joint surfaces will not rotate relative to each other.

[0048] It should be understood that the anti-slip torque can be the minimum torque value required to ensure that the bolt connection does not slip relative to each other when subjected to external loads or vibrations. Specifically in the case of the oil pump fixing bolts, this torque ensures that the bolts can tightly fix the oil pump to prevent it from loosening or falling off due to vibration or pressure changes during engine operation.

[0049] It should be noted that, reference Figure 2 and Figure 3 It can be seen that by comparing the reference anti-slip torques of various contact surfaces, a comparison result is obtained, and the minimum reference anti-slip torque is obtained according to the comparison result. The minimum reference anti-slip torque is used as the anti-slip torque. In the connection system, there are three joint surfaces, namely, the oil pump driven wheel fixing bolt gasket 1-1, the oil pump driven wheel 2 and the oil pump 4. There is an anti-slip torque between each joint surface. The joint surface with the minimum anti-slip torque is prone to relative slip, resulting in bolt loosening and transmission failure.

[0050] The calculation of the driving torque or the minimum torque that the bolt design must meet can refer to the following formula:

[0051] Among them, M i represents the driving torque, μ represents the contact friction force, Fi represents the reference axial force, and Rei represents the equivalent contact radius of each joint surface.

[0052] It is understandable that the anti-slip torque of each contact surface is related to the force of each contact surface, and the force of each contact surface is related to the equivalent contact radius of each contact surface.

[0053] It should be noted that if the anti-slip torque of the bolt is required to meet the demand of the driving torque, then the anti-slip torque must still be greater than or equal to the driving torque when the contact area is minimum. The minimum axial force can be determined based on the minimum contact area and the driving torque, and this axial force can be used as the reference axial force.

[0054] Then, the smallest equivalent contact radius among the equivalent contact radii of each bonding surface is taken as the reference equivalent contact radius, and the following formula can be referred to:

[0055] Among them, min() means taking the equivalent contact radius with the smallest equivalent contact radius.

[0056] It can be understood that, based on the above formula, when the minimum equivalent contact radius is calculated, M i The drive torque requirement is F i The value of F i Bolt selection can meet the selection requirements.

[0057] Step A23, performing axial force attenuation analysis on the reference axial force to obtain a target axial force.

[0058] It is understandable that the target axial force becomes the reference axial force after axial force attenuation, and the target axial force can generally be understood as the assembly force.

[0059] It should be understood that since the oil pump fixing bolt connection system has three mating surfaces, each mating surface has microscopic unevenness and roughness, which causes a large attenuation of the assembly axial force due to microscopic deformation of the bolts after pre-tightening.

[0060] It should be understood that when the engine runs for a long time, the friction coefficient of each mating surface decreases due to contact wear, which makes it easy for it to loosen. In addition, due to long-term mechanical and alternating hot and cold loads, the material of the connected parts creeps and thins, causing the axial force to attenuate.

[0061] It should be noted that the relationship between the axial force before and after the bolt axial force attenuation can refer to the following formula:

[0062] Among them, F v It represents the axial force before attenuation, that is, the target axial force, which can also be understood as the axial force corresponding to the bolt selection. Based on the target axial force, the axial force F after the axial force attenuation i(i.e., the reference axial force) can also meet the requirement of being greater than or equal to the driving torque, where K represents the safety factor of the oil pump fixing bolt, which is usually 2.

[0063] In this embodiment, when multiple parts in the connection system are subjected to lateral external loads at the same time, the part with the worst anti-slip ability in the connection system is inferred by calculating the equivalent radius of each joint surface, and this is used as the lower limit of the axial force that the torsional vibration damper fixing bolt needs to provide under the extreme operation of the engine. This idea clarifies the basis for the bolt axial force design and improves the reliability of the bolt design.

[0064] The above are only feasible implementations of step S20 provided in this embodiment, and this embodiment does not specifically limit the specific implementation of step S20.

[0065] Step S30, obtaining a pre-selected type according to the target axial force, and obtaining a maximum axial force and a minimum axial force of the pre-selected type based on the pre-selected type.

[0066] It is understandable that bolt selection includes selecting the material, specification, size, yield strength range, friction coefficient range, etc. of the bolt.

[0067] It should be understood that the bolt pre-selection can be to preliminarily determine the material, specification, size, yield strength range, friction coefficient range, etc. of the bolt according to the axial force requirement after axial force attenuation analysis of the target axial force. After determination, further work such as safety factor confirmation and strength verification is required to obtain the final bolt selection.

[0068] It is understandable that the minimum axial force and the maximum axial force may be obtained based on the bolt material determined by the bolt pre-selection.

[0069] In a feasible implementation, step S30 may include steps A31 to A34: Step A31: taking the target axial force as a minimum threshold of the tightening force.

[0070] It is understandable that the target axial force is generally taken as the minimum axial force, but due to various factors such as material and selection, the target axial force is taken as the minimum threshold of the tightening force.

[0071] It is understandable that the minimum tightening force threshold is the standard for determining the minimum axial force. To determine the pre-selection type, the minimum axial force corresponding to the bolt pre-selection type should be less than or equal to and close to the minimum tightening force threshold, the closer the better.

[0072] Step A32, determining the yield strength range, friction coefficient range, bolt specifications and dimensions based on the minimum tightening force threshold.

[0073] It is understandable that determining the yield strength range, friction coefficient range, bolt specification and size based on the minimum tightening force threshold is to make the minimum axial force calculated from the selected yield strength range, friction coefficient range, bolt specification and size greater than the minimum tightening force threshold.

[0074] It should be understood that the initial selection is based on the minimum axial force calculated based on various yield strength ranges, friction coefficient ranges, bolt specifications and sizes; for example, when the minimum axial force threshold is 10, some parameters (yield strength range, friction coefficient range, bolt specifications and sizes) calculate the minimum axial force to be 15 and the maximum axial force to be 50; some parameters calculate the minimum axial force to be 20 and the maximum axial force to be 40, then further selection is required based on the maximum and minimum axial forces.

[0075] Step A33, obtaining a pre-selection based on the yield strength range, the friction coefficient range, and the bolt specifications and dimensions.

[0076] It is understandable that once the yield strength range, the friction coefficient range, and the bolt specifications and dimensions are determined, the bolt selection and design can basically be determined.

[0077] Step A34, obtaining the maximum axial force and the minimum axial force of the pre-selected type based on the pre-selected type.

[0078] It should be noted that the pre-selected maximum axial force and minimum axial force obtained based on the pre-selection include: obtaining bolt parameters, and constructing a bolt preload model according to the bolt parameters; obtaining the minimum yield strength and the maximum yield strength based on the yield strength range, and obtaining the maximum friction coefficient and the minimum friction coefficient based on the friction coefficient range; obtaining the minimum axial force through the bolt preload model based on the minimum yield strength and the maximum friction coefficient; and obtaining the maximum axial force through the bolt preload model based on the maximum yield strength and the minimum friction coefficient.

[0079] Among them, it can be understood that the bolt parameters can be understood as the parameters involved in calculating the bolt preload, which can include the yield strength utilization factor, the bolt yield strength, the nominal stress cross-sectional area of ​​the external thread, the bolt thread pitch diameter, the stress cross-sectional area equivalent diameter, the thread flank angle and the thread friction coefficient. The calculation of the bolt preload can refer to the following formula:

[0080] Among them, v is the yield strength utilization factor. For bolts tightened in the elastic domain, the v value range is 70%-90%, and for bolts tightened in the plastic domain, the v value range is 100%-110%; Rp 0.2 is the bolt yield strength, As is the nominal stress cross-sectional area of ​​the external thread, d2 is the bolt thread pitch diameter, d0 is the nominal stress cross-sectional area equivalent diameter, α' is the thread flank angle, μs is the thread friction coefficient.

[0081] It should be noted that the definition of the bolt's preload is mainly related to its bolt specifications and dimensions, yield strength and friction coefficient, which are the key parameters for bolt selection. Bolt specifications and dimensions: The initial specifications and dimensions are limited by the layout boundaries of the center of the oil pump driven wheel and the wall thickness of the crankshaft end face. The maximum specifications of the bolts can be determined based on the above boundaries. Yield strength range: depends on the material batch and production process control dispersion, and the dispersion range is required to be controlled within 100MPa. Friction coefficient range; depends on the surface treatment and anti-rust oil type. The general friction coefficient range of oiling after phosphating is 0.08-0.14; the general friction coefficient range of oiling after blackening is: 0.10-0.16.

[0082] It is understandable that after determining the pre-selected bolt, the corresponding parameters can be selected from the material, specification, size, yield strength range, and friction coefficient range in the pre-selected bolt according to the calculation formula of the assembly preload force to calculate the minimum and maximum axial forces of the bolt.

[0083] Then, based on the above bolt preload model, it can be seen that the yield strength and preload are in direct proportion, and the thread friction coefficient and preload are in inverse proportion. The calculation of the minimum axial force can refer to the following formula:

[0084] It is understandable that the bolt has a minimum yield strength Rp 0.2 and a thread friction coefficient In the maximum state, the minimum assembly preload is generated. The size and tolerance of the bolts are guaranteed by the bolt production mold with high precision; when calculating, the influence of the dimensional tolerance dispersion on the preload is ignored.

[0085] It is understandable that based on the above bolt preload model, the yield strength and preload are in direct proportion, and the thread friction coefficient and preload are in inverse proportion. The calculation of the maximum axial force can refer to the following formula:

[0086] It is understandable that for plastic domain tightening design, under the maximum bolt assembly preload state, the bolt will undergo plastic deformation, and the increase in axial force caused by the cold work hardening of the bolt material must be considered. The cold work hardening coefficient m is usually taken as 1-1.05.

[0087] In this embodiment, during the calculation of the bolt assembly preload force during bolt design, the bolt preload force range is determined after fully considering the deviation of key parameters such as yield strength and friction coefficient of the bolt in mass production, and the design reliability is high.

[0088] The above are only feasible implementations of step S30 provided in this embodiment, and this embodiment does not specifically limit the specific implementation of step S30.

[0089] Step S40, when the minimum anti-slip torque corresponding to the minimum axial force is greater than the rotational torque, obtaining a verification parameter according to the maximum axial force and the minimum axial force.

[0090] It can be understood that the minimum axial force is the pre-selected minimum axial force. When the minimum anti-slip torque corresponding to the minimum axial force is greater than the rotational torque, it can be understood that the anti-slip torque brought by the axial force provided by the pre-selection of the bolt can support the driving torque brought by the vehicle when driving, and effectively avoid being connected and crushed, resulting in excessive attenuation of the bolt preload or even failure.

[0091] It should be noted that the verification parameters may include safety parameters, stress parameters and thread strength parameters.

[0092] Step S50, when the verification parameters meet the preset parameter requirements, the pre-selected type is used as the target bolt type.

[0093] It is understandable that the design of bolts has certain requirements in terms of engineering, mechanics, safety, etc., and each requirement can be reflected in whether the various parameters provided by the bolts meet the standards.

[0094] It should be understood that the verification parameters are obtained based on the maximum axial force and the minimum axial force corresponding to the bolt preselectivity, and the verification parameters are compared with various preset parameters. The preset parameters may include the standard values ​​corresponding to the various verification parameters.

[0095] It should be noted that if all verification parameters meet the requirements of the qualified values ​​in the preset parameters, it can be understood that the pre-selectivity of the bolt design meets the conditions for the use of the bolt; if the preset parameters are not met, the selection can be re-based on the minimum axial force until the requirements are met.

[0096] It is understandable that the requirement for each verification parameter may be greater than the corresponding standard value, or may be less than the corresponding standard value, as long as the corresponding requirement is met.

[0097] In the specific implementation, the selection process of the oil pump sprocket fixing bolt can refer to Figure 4, the maximum oil pressure and maximum flow rate of the oil pump are pre-entered in the figure, so as to obtain the oil pump driving torque, and the minimum slip torque is obtained based on the oil pump driving torque. The minimum axial force required for tightening the oil pump sprocket is determined based on the minimum slip torque and the pre-entered outer diameter, inner diameter of the mating surface of each part of the oil pump sprocket fixing bolt connection system and the equivalent contact radius of each mating surface. The assembly preload required by the bolt is calculated according to the minimum axial force based on the axial force attenuation factor, so as to preliminarily select the bolt specifications, yield strength range, friction coefficient range, etc. and determine the minimum assembly preload of the bolt, that is, the minimum axial force, and further determine the maximum axial force, and then further confirm the bolt safety factor, check the strength of the connected parts and check the thread strength. Finally, design freeze can be understood as the design is completed and the pre-selected type of the bolt is saved.

[0098] The present embodiment provides a bolt selection method, which determines the minimum axial force that the bolt should have by the engine torque and the associated parameters of the bolt under various working conditions, obtains a bolt pre-selection based on the minimum axial force, and performs bolt verification based on the pre-selection to obtain a bolt selection that meets the requirements, thereby effectively improving the reliability of the bolt design, thereby obtaining a bolt type that better meets the standards, and avoiding the oil pump from not working properly due to inaccurate selection of the bolt type.

[0099] Based on the first embodiment of the present application, in the second embodiment of the present application, the same or similar contents as those in the above-mentioned embodiment 1 can be referred to the above introduction, and will not be repeated in the following. Figure 5 , step S40, the bolt selection method further includes steps S41 to S44: Step S41, when the minimum axial force is greater than the preset axial force of the rotational torque, a safety parameter is obtained according to the minimum axial force and the reference axial force.

[0100] It should be noted that the calculation of safety parameters can refer to the following formula:

[0101] Among them, F Mmin Indicates the minimum axial force, F v represents the reference axial force, and K' represents the safety parameter.

[0102] It should be noted that the preset parameter corresponding to the safety parameter is the safety factor of the oil pump fixing bolt, which is usually 2. When K' is greater than or equal to the safety factor of the oil pump fixing bolt, it is considered that the safety parameter meets the preset parameter requirements.

[0103] It should be emphasized that K' can be larger than the safety factor of the oil pump fixing bolts but should be as close as possible, otherwise the design margin will be too large, resulting in material waste.

[0104] Step S42, obtaining each contact surface area according to the associated part parameters, and obtaining stress parameters according to each contact surface area and the maximum axial force.

[0105] It should be noted that the reference Figure 2 and Figure 3 There are multiple connected parts in the oil pump fixing bolt connection system, including the oil pump fixing bolt and gasket, the oil pump driven wheel and the oil pump body. The contact area of ​​each joint surface can be calculated by referring to the following formula:

[0106] Among them, A i Represents the contact area of ​​each bonding surface.

[0107] It is understandable that each joint surface is subjected to a large contact stress and is required not to exceed the allowable contact stress limit of the material.

[0108] It should be noted that the calculation of the contact stress of each joint surface can refer to the following formula:

[0109] Among them, F Mmax Indicates the bolt axial force, A i represents the contact area of ​​the bonding surface, σ i Represents the contact stress of each bonding surface.

[0110] It should be emphasized that the recommended material allowable contact stress limit for alloy steel bolt washers is 980MPa, and the oil pump sprocket is usually made of structural steel material, and the recommended allowable contact stress limit is 559MPa.

[0111] It is understandable that the stress requirements corresponding to the stress parameters will vary based on different bolt selection materials. When the contact stress on each joint surface is less than the contact stress limit of the material, the stress parameter is considered to meet the preset parameter requirements.

[0112] Step S43, obtaining thread parameters, and obtaining thread strength parameters according to the thread parameters and the maximum axial force.

[0113] It should be noted that thread parameters may include pitch, thread diameter (major diameter, minor diameter and pitch diameter), thread profile angle, etc.

[0114] It should be noted that the internal thread of the oil pump fixing bolt is set in the oil pump body. Usually, the shear strength of the internal bolt is lower than the tensile strength of the oil pump fixing bolt, and it is necessary to check whether the screwing length of the inner and outer bolts meets the strength requirements. Therefore, it is necessary to check the strength of the internal thread of the oil pump fixing bolt under the maximum assembly force state.

[0115] In a feasible implementation, step S43 may include steps A431-A432: Step A431, obtaining thread parameters, and obtaining the internal thread shear equivalent cross-sectional area according to the thread parameters.

[0116] It is understandable that the shear equivalent cross-sectional area is an important indicator for evaluating the shear strength of internal threads. The calculation of the shear equivalent cross-sectional area can refer to the following formula:

[0117] Where D2 is the major diameter of the thread, d is the minor diameter of the thread, and L e is the screwing length, P is the pitch, A s1 Represents the shear equivalent cross-sectional area.

[0118] Step A432, obtaining the allowable shear force of the internal thread according to the equivalent shear cross-sectional area of ​​the internal thread, and obtaining the thread strength parameter according to the and the maximum axial forces.

[0119] It should be noted that the allowable shear force of the internal thread can be obtained according to the equivalent shear cross-sectional area of ​​the internal thread by referring to the following formula:

[0120] Among them, F n It represents the allowable shear force of the internal thread. τ can be understood as the allowable shear stress of the material, which can usually be found in the mechanical properties table of the material.

[0121] Further, the thread strength parameter can be obtained according to the above and the above maximum axial force by referring to the following formula:

[0122] Among them, K2 represents the thread strength parameter, and the corresponding thread strength preset parameter requirement is generally set to 3. When the thread strength parameter is greater than or equal to 3, it can be considered that the thread strength parameter meets the preset parameter.

[0123] In this embodiment, the thread strength parameter is obtained by the thread parameter and the maximum axial force. The shear strength of the internal thread will be lower than the tensile strength of the external bolt. The thread strength is calculated to determine whether it meets the thread production requirements.

[0124] The above are only feasible implementations of step S43 provided in this embodiment, and this embodiment does not specifically limit the specific implementation of step S43.

[0125] The present embodiment provides a bolt selection method. When the minimum anti-slip torque corresponding to the minimum axial force is greater than the rotational torque, the verification parameters of the bolt pre-selection are calculated according to the maximum axial force and the minimum axial force of the bolt pre-selection. Based on the verification parameters, the bolt pre-selection is evaluated from multiple aspects such as safety, structural performance and bolt strength, so as to obtain a bolt selection that meets the requirements, thereby effectively improving the reliability of the bolt design.

[0126] It should be noted that the above examples are only used to understand the present application and do not constitute a limitation on the bolt selection method of the present application. More simple transformations based on this technical concept are all within the scope of protection of the present application.

[0127] This application also provides a bolt selection device, please refer to Figure 6 , the bolt selection device comprises: The parameter acquisition module 10 is used to acquire the associated part parameters and driving torque of the bolt; An axial force analysis module 20, configured to obtain a reference axial force according to the associated component parameters and the driving torque, and perform an axial force attenuation analysis on the reference axial force to obtain a target axial force; The axial force analysis module 20 is further used to obtain a pre-selection according to the target axial force, and obtain the maximum axial force and the minimum axial force of the pre-selection based on the pre-selection; A selection and verification module 30, configured to obtain a verification parameter according to the maximum axial force and the minimum axial force when the minimum anti-slip torque corresponding to the minimum axial force is greater than the rotational torque; The selection and verification module 30 is further configured to use the pre-selected type as the target bolt type when the verification parameters meet the preset parameter requirements.

[0128] The bolt selection device provided by the present application adopts the bolt selection method in the above embodiment, which can solve the technical problem in the prior art that the bolt type selection is not accurate enough during the selection of the fixing bolts of the chain-driven oil pump, resulting in the oil pump not being able to work properly. Compared with the prior art, the beneficial effects of the bolt selection device provided by the present application are the same as the beneficial effects of the bolt selection method provided by the above embodiment, and the other technical features of the bolt selection device are the same as the features disclosed in the above embodiment method, which will not be repeated here.

[0129] The present application provides a bolt selection device, which includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the bolt selection method in the above-mentioned embodiment one.

[0130] Reference below Figure 7, which shows a schematic diagram of the structure of a bolt selection device suitable for implementing the embodiment of the present application. The bolt selection device in the embodiment of the present application may include but is not limited to mobile terminals such as mobile phones, laptop computers, digital broadcast receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Descriptions), PMPs (Portable Media Players), vehicle-mounted terminals (such as vehicle-mounted navigation terminals), etc., and fixed terminals such as digital TVs, desktop computers, etc. Figure 7 The bolt selection device shown is merely an example and should not bring any limitation to the functions and scope of use of the embodiments of the present application.

[0131] like Figure 7 As shown, the bolt selection device may include a processing device 1001 (such as a central processing unit, a graphics processor, etc.), which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM: Read Only Memory) 1002 or a program loaded from a storage device 1003 to a random access memory (RAM: Random Access Memory) 1004. In RAM1004, various programs and data required for the operation of the bolt selection device are also stored. The processing device 1001, ROM1002 and RAM1004 are connected to each other through a bus 1005. An input / output (I / O) interface 1006 is also connected to the bus. Generally, the following systems can be connected to the I / O interface 1006: an input device 1007 including, for example, a touch screen, a touch pad, a keyboard, a mouse, an image sensor, a microphone, an accelerometer, a gyroscope, etc.; an output device 1008 including, for example, a liquid crystal display (LCD: Liquid Crystal Display), a speaker, a vibrator, etc.; a storage device 1003 including, for example, a magnetic tape, a hard disk, etc.; and a communication device 1009. The communication device 1009 can allow the bolt selection device to communicate with other devices wirelessly or wired to exchange data. Although the bolt selection device with various systems is shown in the figure, it should be understood that it is not required to implement or have all the systems shown. More or fewer systems can be implemented or have alternatively.

[0132] In particular, according to the embodiments disclosed in the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, the embodiments disclosed in the present application include a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through a communication device, or installed from a storage device 1003, or installed from a ROM 1002. When the computer program is executed by the processing device 1001, the above-mentioned functions defined in the method of the embodiment disclosed in the present application are executed.

[0133] The bolt selection device provided by the present application adopts the bolt selection method in the above embodiment, which can solve the technical problem in the prior art that the bolt type selection is not accurate enough during the selection of the fixing bolts of the chain-driven oil pump, resulting in the oil pump not being able to work normally. Compared with the prior art, the beneficial effects of the bolt selection device provided by the present application are the same as the beneficial effects of the bolt selection method provided by the above embodiment, and the other technical features of the bolt selection device are the same as the features disclosed in the method of the previous embodiment, which will not be repeated here.

[0134] It should be understood that the various parts disclosed in this application can be implemented by hardware, software, firmware or a combination thereof. In the description of the above embodiments, specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0135] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0136] The present application provides a computer-readable storage medium having computer-readable program instructions (ie, computer programs) stored thereon, and the computer-readable program instructions are used to execute the bolt selection method in the above-mentioned embodiment.

[0137] The computer-readable storage medium provided in the present application may be, for example, a USB flash drive, but is not limited to electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, systems or devices, or any combination of the above. More specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM: Random Access Memory), a read-only memory (ROM: Read Only Memory), an erasable programmable read-only memory (EPROM: Erasable Programmable Read Only Memory or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM: CD-Read Only Memory), an optical storage device, a magnetic storage device, or any suitable combination of the above. In this embodiment, the computer-readable storage medium may be any tangible medium containing or storing a program, which may be used by or in combination with an instruction execution system, system or device. The program code contained on the computer-readable storage medium may be transmitted using any appropriate medium, including but not limited to: wires, optical cables, RF (Radio Frequency: Radio Frequency), etc., or any suitable combination of the above.

[0138] The computer-readable storage medium may be included in the bolt selection device; or may exist independently without being assembled into the bolt selection device.

[0139] The above-mentioned computer-readable storage medium carries one or more programs. When the above-mentioned one or more programs are executed by the bolt selection device, the bolt selection device is enabled to: obtain the associated part parameters and driving torque of the bolt; obtain the reference axial force according to the associated part parameters and the driving torque, perform axial force attenuation analysis on the reference axial force, and obtain the target axial force; obtain a pre-selection according to the target axial force, and obtain the maximum axial force and minimum axial force of the pre-selected type based on the pre-selection; when the minimum axial force is greater than the preset axial force of the rotational torque, obtain verification parameters according to the maximum axial force and the minimum axial force; when the verification parameters meet the preset parameter requirements, use the pre-selection as the target bolt selection.

[0140] Computer program code for performing the operations of the present application may be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, as a separate software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0141] The flow chart and block diagram in the accompanying drawings illustrate the possible architecture, function and operation of the system, method and computer program product according to various embodiments of the present application. In this regard, each square box in the flow chart or block diagram can represent a module, a program segment or a part of a code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the square box can also occur in a sequence different from that marked in the accompanying drawings. For example, two square boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each square box in the block diagram and / or flow chart, and the combination of the square boxes in the block diagram and / or flow chart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0142] The modules involved in the embodiments described in this application may be implemented by software or hardware, wherein the name of the module does not constitute a limitation on the unit itself in some cases.

[0143] The readable storage medium provided by the present application is a computer-readable storage medium, which stores computer-readable program instructions (i.e., computer programs) for executing the above-mentioned bolt selection method, and can solve the technical problem in the prior art that the selection of bolt types is not accurate enough during the selection of chain-driven oil pump fixing bolts, resulting in the oil pump not being able to work properly. Compared with the prior art, the beneficial effects of the computer-readable storage medium provided by the present application are the same as the beneficial effects of the bolt selection method provided by the above-mentioned embodiment, and will not be repeated here.

[0144] The present application also provides a computer program product, including a computer program, which implements the steps of the bolt selection method as described above when executed by a processor.

[0145] The computer program product provided by the present application can solve the technical problem in the prior art that the selection of bolt types during the selection of bolts for chain-driven oil pump fixing bolts is not accurate enough, resulting in the oil pump not being able to work properly. Compared with the prior art, the beneficial effects of the computer program product provided by the present application are the same as the beneficial effects of the bolt selection method provided by the above embodiment, and will not be elaborated here.

[0146] The above descriptions are only some embodiments of the present application, and are not intended to limit the patent scope of the present application. All equivalent structural changes made using the contents of the present application specification and drawings under the technical concept of the present application, or direct / indirect applications in other related technical fields are included in the patent protection scope of the present application.

Claims

1. A bolt selection method, characterized in that: The bolt selection method includes: Get the associated part parameters and driving torque of the bolt; Obtain a reference axial force according to the associated part parameters and the driving torque, and perform axial force attenuation analysis on the reference axial force to obtain a target axial force; Obtain a preselected type according to the target axial force, and obtain a maximum axial force and a minimum axial force of the preselected type based on the preselected type; When the minimum anti-slip torque corresponding to the minimum axial force is greater than the rotational torque, obtaining a verification parameter according to the maximum axial force and the minimum axial force; When the verification parameters meet the preset parameter requirements, the pre-selected type is used as the target bolt type.

2. The bolt selection method according to claim 1, characterized in that: The part parameters include the contact inner diameter and contact outer diameter of each joint surface with the bolt; The step of obtaining a reference axial force according to the associated part parameters and the driving torque, and performing axial force attenuation analysis on the reference axial force to obtain a target axial force includes: Obtaining an equivalent contact radius of each bonding surface according to the contact inner diameter and the contact outer diameter; Obtaining a reference axial force according to the driving torque and the equivalent contact radius of each of the combined surfaces; An axial force attenuation analysis is performed on the reference axial force to obtain a target axial force.

3. The bolt selection method according to claim 2, characterized in that: The obtaining of the reference axial force according to the driving torque and the equivalent contact radius of each of the combined surfaces comprises: The smallest equivalent contact radius among the equivalent contact radii of each bonding surface is used as a reference equivalent contact radius; A reference axial force is obtained according to the reference equivalent contact radius and the driving torque.

4. The bolt selection method according to claim 1, characterized in that: The step of obtaining a pre-selected type according to the target axial force, and obtaining a maximum axial force and a minimum axial force of the pre-selected type based on the pre-selected type, comprises: Using the target axial force as a minimum threshold of the tightening force; Determining a yield strength range, a friction coefficient range, bolt specifications and dimensions based on the minimum tightening force threshold; A pre-selection is obtained based on the yield strength range, the friction coefficient range, and the bolt specification and size; Based on the pre-selection, the maximum axial force and the minimum axial force of the pre-selection are obtained.

5. The bolt selection method according to claim 4, characterized in that: The obtaining of the maximum axial force and the minimum axial force of the pre-selected type based on the pre-selected type includes: Obtaining bolt parameters, and constructing a bolt preload model according to the bolt parameters; Based on the yield strength range, a minimum yield strength and a maximum yield strength are obtained, and based on the friction coefficient range, a maximum friction coefficient and a minimum friction coefficient are obtained; Obtaining a minimum axial force through the bolt preload model based on the minimum yield strength and the maximum friction coefficient; The maximum axial force is obtained through the bolt preload model based on the maximum yield strength and the minimum friction coefficient.

6. The bolt selection method according to claim 1, characterized in that: The verification parameters include safety parameters, stress parameters and thread strength parameters; When the minimum anti-slip torque corresponding to the minimum axial force is greater than the rotational torque, obtaining the verification parameter according to the maximum axial force and the minimum axial force includes: When the minimum axial force is greater than a preset axial force of the rotational torque, a safety parameter is obtained according to the minimum axial force and the reference axial force; Obtaining the areas of each contact surface according to the associated part parameters, and obtaining stress parameters according to the areas of each contact surface and the maximum axial force; Thread parameters are obtained, and thread strength parameters are obtained according to the thread parameters and the maximum axial force.

7. The bolt selection method according to claim 6, characterized in that: The obtaining of thread parameters, and obtaining thread strength parameters according to the thread parameters and the maximum axial force, includes: Obtaining thread parameters, and obtaining the internal thread shear equivalent cross-sectional area according to the thread parameters; The allowable shear force of the internal thread is obtained according to the equivalent shear cross-sectional area of ​​the internal thread, and the thread strength parameter is obtained according to the and the maximum axial forces.

8. A bolt selection device, characterized in that: The bolt selection device comprises: A parameter acquisition module is used to obtain the associated part parameters and driving torque of the bolt; An axial force analysis module, used for obtaining a reference axial force according to the associated part parameters and the driving torque, performing an axial force attenuation analysis on the reference axial force, and obtaining a target axial force; The axial force analysis module is further used to obtain a pre-selected type according to the target axial force, and obtain a maximum axial force and a minimum axial force of the pre-selected type based on the pre-selected type; A selection and verification module, configured to obtain a verification parameter according to the maximum axial force and the minimum axial force when the minimum anti-slip torque corresponding to the minimum axial force is greater than the rotational torque; The selection and verification module is also used to use the pre-selection as the target bolt selection when the verification parameters meet the preset parameter requirements.

9. A bolt selection device, characterized in that: The device comprises: a memory, a processor, and a bolt selection program stored in the memory and executable on the processor, wherein the bolt selection program is configured to implement the bolt selection method according to any one of claims 1 to 7.

10. A storage medium, characterized in that: The storage medium stores a bolt selection program, and when the bolt selection program is executed by the processor, the bolt selection method according to any one of claims 1 to 7 is implemented.

Images