Assembly for simulating screw joint surface and joint surface friction coefficient detection device

Abstract

The utility model provides an assembly for simulating a screw joint surface and a joint surface friction coefficient detection device, relates to the field of friction coefficient detection, and adopts the technical scheme that a simulation block assembly is arranged at one end of a mounting seat and comprises a simulation block I and a simulation block II, and a sliding block is arranged between the simulation block I and the simulation block II; the sliding block is used for bearing sliding force, two side surfaces of the sliding block are respectively contacted with the simulation block I and the simulation block II, and the material, the surface treatment process and the roughness of the sliding block are the same as those of a part at the joint surface to be tested; the materials, the surface treatment process and the roughness of the simulation block I and the simulation block II are the same as those of the other part at the joint surface to be detected; and a bolt pre-tightening force applying assembly is arranged at the other end of the mounting seat. The friction coefficient can be accurately determined in the bolt tightening process optimization and design development process, the friction coefficient obtaining accuracy is improved, and the situation that bolt model selection cannot meet the actual working condition requirement is avoided.

Description

Technical Field

[0001] The utility model relates to the field of friction coefficient detection, in particular to a component simulating a screw joint surface and a joint surface friction coefficient detection device. Background Art

[0002] Bolted connections, as a common connection method, offer high strength and stability, ensuring that connected components remain stable and reliable under various loads. Furthermore, bolted connections are simple to operate, requiring only basic torque tools. Bolted connections are not permanent components and can be reused, reducing operating costs and improving resource utilization. Bolted connections offer significant technical advantages in engineering structures. As technology advances, assembly processes become increasingly complex, and the reliability requirements for achieving the highest quality standards are increasing. This necessitates adapting the design of optimized tightening and assembly systems to actual working conditions.

[0003] During the optimization and design development of the bolt tightening process, the main process is: simulation design → torque verification calculation → on-site experiment → process batch verification → process decentralization. During the entire forward development process, including multiple stages such as axial force simulation analysis, it is necessary to determine the friction coefficient of the joint surface between the components clamped by the bolt. To ensure the versatility and reliability of the design, most companies adopt the friction coefficient used in industry practices.

[0004] However, there is a difference between the friction coefficient determined by querying the friction coefficient used in industry practices and the friction coefficient of actual parts, which will lead to inaccurate calculation results. The final result in process development is that the selection of bolts in the theoretical design stage does not match the actual parts in subsequent production, which poses quality risks to the product. Utility Model Content

[0005] In order to solve the technical problem in the above-mentioned prior art that the friction coefficient of the joint surface cannot be accurately determined during the optimization and design development of the bolt tightening process, the utility model provides a component that simulates the threaded joint surface and a joint surface friction coefficient detection device, which can accurately determine the friction coefficient during the optimization and design development of the bolt tightening process, improve the accuracy of friction coefficient acquisition, and avoid the bolt selection not meeting the actual working conditions.

[0006] In the first aspect, in order to solve the above-mentioned technical problems, the utility model provides a component for simulating a threaded joint surface, including a mounting seat, a mounting cavity is provided at one end of the mounting seat, a simulation block component is provided in the mounting cavity, the simulation block component includes simulation block 1 and simulation block 2, a sliding block is provided between simulation block 1 and simulation block 2, the sliding block is used to bear the sliding force, the two side surfaces of the sliding block are in contact with simulation block 1 and simulation block 2 respectively, the sliding block extends out of the mounting cavity, the material, surface treatment process and roughness of the sliding block are the same as those of a component at the joint surface to be measured, the material, surface treatment process and roughness of simulation block 1 and simulation block 2 are the same as those of another component at the joint surface to be measured, a bolt pre-tightening force applying component is provided at the other end of the mounting seat, the bolt pre-tightening force applying component is used to provide the bolt pre-tightening force at the joint surface to be measured, the bolt pre-tightening force applying component includes a force rod, the length direction of the force rod is perpendicular to the sliding force direction, and the force rod can abut against the surface of simulation block 1.

[0007] The utility model simulates the two parts at the joint surface by setting a simulation block assembly, and applies the pre-tightening force after the bolt is tightened through the bolt pre-tightening force applying assembly, so as to simulate the actual working conditions of the joint surface, and then accurately calculate the friction coefficient according to the test results, thereby improving the accuracy of obtaining the friction coefficient and avoiding the bolt selection failing to meet the needs of the actual working conditions.

[0008] Furthermore, the upper end of the sliding block extends out of the mounting cavity, and two limit blocks are relatively provided on the upper surface of the mounting seat and located at the edge of the mounting cavity. The limit blocks can abut against the simulation block one or the simulation block two.

[0009] The utility model can prevent the first simulation block and the second simulation block from moving by setting the limit block, thereby avoiding the accurate calculation of the friction coefficient of the joint surface.

[0010] Furthermore, the mounting seat includes an upper mounting plate and a lower mounting plate, a mounting block is screwed between the upper mounting plate and the lower mounting plate, the mounting cavity is provided in the mounting block, the upper mounting plate is provided with a corresponding mounting hole 1, the limit block is provided at the edge of the mounting hole 1, and the sliding block extends from the mounting hole 1.

[0011] The utility model provides a mounting base as a split detachable structure, which makes it easy to transport and install the mounting base on a corresponding test device.

[0012] Furthermore, the bolt preload force applying assembly includes a hydraulic cylinder, which is arranged on the lower mounting plate.

[0013] The utility model applies pressure to simulate the pre-tightening force through the hydraulic cylinder, which can maintain the stability of the pressure during the test and further improve the accuracy of obtaining the friction coefficient.

[0014] Furthermore, a pressure sensor is connected between the piston rod of the hydraulic cylinder and the force applying rod, and the pressure sensor is electrically connected to the display.

[0015] The utility model can visually monitor the size of the pressure applied by the hydraulic cylinder through the pressure sensor and the display, which is convenient for adjustment and control.

[0016] Furthermore, baffles are respectively provided on the lower mounting plate and on both sides of the pressure sensor.

[0017] The utility model can prevent the pressure sensor from deflecting during the movement by arranging the baffle.

[0018] In the second aspect, the utility model also provides a device for detecting the friction coefficient of the joint surface of a bolt tightening, including the above-mentioned component of the simulated threaded joint surface, and also including a universal testing machine body, the universal testing machine body including a support platform and a force-applying member, a clamping seat is provided on the support platform, and the lower mounting plate is detachably connected to the clamping seat.

[0019] The utility model uses the universal testing machine body in the prior art to carry out relevant tests, which is convenient for determining the critical slip force, can save the design and manufacture of the corresponding test device, shorten the manufacturing cycle of the joint surface friction coefficient detection device, and reduce the manufacturing cost.

[0020] Furthermore, an avoidance groove is provided on one side of the upper end of the sliding block.

[0021] The utility model is convenient for the universal testing machine body to clamp the sliding block and exert an upward sliding force by arranging the avoidance groove.

[0022] Furthermore, a positioning column is provided at the lower portion of the mounting seat where one end of the simulation block assembly is mounted, and a positioning hole is provided on the positioning column along its radial direction.

[0023] The utility model is convenient for installing and clamping components of the simulated screw connection surface by arranging the positioning columns.

[0024] Furthermore, a leveling foot is provided at the lower portion of one end of the mounting seat on which the bolt preload force applying assembly is mounted, and a spirit level is provided on the mounting seat.

[0025] The utility model can ensure that the test is carried out in a horizontal state when the mounting seat is provided with the leveling feet, ensure that the sliding force applied by the universal testing machine body is the friction force received by the sliding block, and improve the accuracy of the test.

[0026] It can be seen from the above technical solutions that the present invention has the following advantages:

[0027] The utility model provides a component for simulating a screw-connected joint surface and a joint surface friction coefficient detection device. By arranging a simulation block component to simulate two parts at the joint surface, and applying a pre-tightening force after the bolts are tightened by a bolt pre-tightening force applying component, the actual working condition of the joint surface can be simulated, and then the friction coefficient can be accurately calculated based on the test results, thereby improving the accuracy of obtaining the friction coefficient and avoiding the situation where the bolt selection cannot meet the actual working condition requirements; by arranging a limit block, the simulation block one and the simulation block two can be prevented from moving, thereby avoiding the accurate calculation of the joint surface friction coefficient; by arranging the mounting seat into a split detachable structure, it is convenient to transport and install the mounting seat to a corresponding test device or test bench; by applying pressure simulating the pre-tightening force by a hydraulic cylinder, the stability of the pressure during the test can be maintained, thereby further improving the accuracy of obtaining the friction coefficient; by using a pressure sensor and a display, the size of the pressure applied by the hydraulic cylinder can be intuitively monitored, thereby facilitating adjustment and control; by arranging a baffle, the pressure sensor can be prevented from shifting during movement; by using a universal testing machine body in the prior art to carry out relevant tests, the critical slip force can be determined, the design and manufacture of the corresponding test device can be omitted, the manufacturing cycle of the joint surface friction coefficient detection device can be shortened, and the manufacturing cost can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solution of the present invention, the following is a brief introduction to the drawings required for the description. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0029] Figure 1 This is a structural diagram of a specific implementation method of the present invention.

[0030] Figure 2 This is a structural diagram of a specific embodiment of the present invention after removing the upper mounting plate.

[0031] Figure 3 This is a schematic diagram of the assembly structure of the simulation block assembly, the force application rod and the limit block in the first specific implementation mode of the present invention.

[0032] Figure 4 This is a structural diagram of a second specific implementation method of the present utility model.

[0033] Figure 5 This is a force-displacement curve diagram obtained in the second specific implementation method of the present invention.

[0034] In the figure, 1. Bolt preload force application assembly; 101. Hydraulic cylinder; 2. Mounting seat; 201. Lower mounting plate; 202. Mounting block; 203. Upper mounting plate; 3. Simulation block assembly; 301. Sliding block; 302. Simulation block 2; 303. Simulation block 1; 4. Positioning column; 5. Baffle; 6. Pressure sensor; 7. Leveling foot; 8. Limit block; 9. Force rod; 10. Force member; 11. Support platform; 12. Clamping seat. DETAILED DESCRIPTION

[0035] In order to make the purpose, features, and advantages of the present invention more obvious and easy to understand, the technical solutions of the present invention will be clearly and completely described below in conjunction with the drawings in the specific embodiments. Obviously, the embodiments described below are only part of the embodiments of the present invention, not all of them. Based on the embodiments in this patent, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this patent. Specific implementation method 1

[0037] like Figure 1 and Figure 2 As shown, this specific embodiment provides a component for simulating a screw joint surface, including a mounting seat 2, a simulation block component 3 and a bolt preload force applying component 1. One end of the mounting seat 2 is provided with a mounting cavity, and a simulation block component 3 is provided in the mounting cavity. The simulation block component 3 includes a simulation block 1 303 and a simulation block 2 302. A sliding block 301 is provided between the simulation block 1 303 and the simulation block 2 302. The sliding block 301 is used to withstand the sliding force. The two side surfaces of the sliding block 301 are in contact with the simulation block 1 303 and the simulation block 2 302 respectively. The sliding block 301 extends out of the mounting cavity. The material, surface treatment process and roughness of the sliding block 301 are the same as those of a component at the joint surface to be measured, the material, surface treatment process and roughness of the simulation block 1 303 and the simulation block 2 302 are the same as those of another component at the joint surface to be measured, and a bolt preload applying assembly 1 is provided at the other end of the mounting seat 2. The bolt preload applying assembly 1 is used to provide a bolt preload at the joint surface to be measured, and the bolt preload applying assembly 1 includes a force applying rod 9. The length direction of the force applying rod 9 is perpendicular to the sliding force direction, and the force applying rod 9 can abut against the surface of the simulation block 1 303.

[0038] This specific embodiment simulates the two parts at the joint surface by setting a simulation block component 3, and applies the preload force after the bolt is tightened through the bolt preload force applying component 1, so as to simulate the actual stress condition of the joint surface. During the test, a sliding force is applied to the sliding block 301 until the sliding block 301 moves to obtain the critical sliding force. The friction coefficient is accurately obtained by calculating the relevant data of the test according to the formula, thereby improving the accuracy of the friction coefficient acquisition and avoiding the bolt selection failing to meet the actual working conditions.

[0039] like Figure 1 and Figure 3 As shown, in order to avoid the movement of simulation block 1 303 and simulation block 2 302, which affects the determination of the critical slip force, in this specific embodiment, the upper end of the sliding block 301 extends out of the mounting cavity to facilitate force application, and two limit blocks 8 are relatively arranged on the upper surface of the mounting seat 2 and located at the edge of the mounting cavity. The limit blocks 8 are connected to the mounting seat 2 by bolts. The limit blocks 8 can abut against simulation block 1 303 or simulation block 2 302. In this specific embodiment, the limit blocks 8 are L-shaped.

[0040] like Figure 1 As shown, since the tooling needs to be installed on other equipment to apply sliding force for testing, the mounting seat 2 includes an upper mounting plate 203 and a lower mounting plate 201, and a mounting block 202 is screwed between the upper mounting plate 203 and the lower mounting plate 201, and a mounting cavity is provided in the mounting block 202, and the upper mounting plate 203 is provided with a corresponding mounting hole 1, and the limit block 8 is provided at the edge of the mounting hole 1, and the sliding block 301 extends from the mounting hole 1; after such arrangement, the upper mounting plate 203 and the lower mounting plate 201 are detachably connected through the mounting block 202, which is convenient for the tooling to be installed on other equipment that applies sliding force.

[0041] In the actual working conditions of the joint surface, the preload force of the bolt does not change. In order to ensure that a stable preload force is provided during the test, in this specific embodiment, the bolt preload force application assembly 1 includes a hydraulic cylinder 101 and a connecting plate. The hydraulic cylinder 101 is arranged on the lower mounting plate 201 through the connecting plate and bolts. A accommodating cavity is provided at the corresponding position of the upper mounting plate 203 to accommodate the cylinder body part of the hydraulic cylinder 101; in order to realize intuitive observation of the working pressure of the hydraulic cylinder 101, in this specific embodiment, a pressure sensor 6 is connected between the piston rod of the hydraulic cylinder 101 and the force rod 9, and the pressure sensor 6 is electrically connected to the display; at the same time, baffles 5 are respectively provided on the lower mounting plate 201 and on both sides of the pressure sensor 6. Specific implementation method 2

[0043] like Figure 4 and Figure 5 As shown, this specific embodiment provides a device for detecting the friction coefficient of a joint surface, including the component of the simulated screw joint surface of the specific embodiment one, and also includes a universal testing machine body, the universal testing machine body includes a support platform 11 and a force-applying member 10, a clamping seat 12 is provided on the support platform 11, and the lower mounting plate 201 is detachably connected to the clamping seat 12, and the pressure block of the universal testing machine body can clamp the sliding block 301 and pull it upward.

[0044] This specific embodiment utilizes a universal testing machine body in the prior art to conduct relevant tests and provide a sliding force. The force-displacement curve of the sliding block 301 can be obtained by utilizing the inherent function of the universal testing machine body. The curve facilitates the determination of the critical sliding force, thereby improving the accuracy of the critical sliding force determination. At the same time, it can eliminate the need for the design and manufacture of corresponding test equipment, shorten the manufacturing cycle of the present joint surface friction coefficient detection device, and reduce manufacturing costs.

[0045] In order to adapt to the universal testing machine body and facilitate force application and clamping, in this specific embodiment, an avoidance groove is provided on one side of the upper end of the sliding block 301, and a positioning column 4 is provided at the lower part of the mounting seat 2 on which one end of the simulation block assembly 3 is mounted. The positioning column 4 is provided with a positioning hole along its radial direction, and the positioning pin on the positioning seat can be inserted into the positioning hole.

[0046] In order to ensure that the critical sliding force is equal to the friction force applied to the sliding block 301 when it is in a balanced state, it is necessary to ensure that the sliding block 301 is installed in a vertical state during the test, so that no component forces in other directions are generated. In this specific embodiment, the mounting seat 2 is equipped with a bolt preload force application assembly 1, and a leveling foot 7 is provided at the lower part of one end. A spirit level is provided on the mounting seat 2, and the spirit level adopts a bubble level.

[0047] In this specific embodiment, the universal testing machine body is a mature product that can be purchased on the market, and its structure will not be described in detail in this article.

[0048] The working process of the friction coefficient detection device for the joint surface of bolt tightening is as follows:

[0049] First, install the lower mounting plate 201 on the supporting platform 11, adjust the leveling feet 7, observe the spirit level until it is level, install the hydraulic cylinder 101, the mounting block 202 and the upper mounting plate 203 in sequence, place the simulation block assembly 3, and install the limit block 8; the hydraulic cylinder 101 applies the set working pressure, and the universal testing machine body clamps the sliding block 301 and applies an upward pulling force, which is gradually increased until the sliding block 301 slides, and the force-displacement curve of the sliding block 301 is obtained. From the force-displacement curve, find the point with the largest tensile stress, and look to the left for the point where the slope changes significantly. The force corresponding to this point is the critical sliding force, which is substituted into the formula to calculate the friction coefficient of this group. To improve accuracy and avoid the influence of the processing technology and material of the sliding block 301, simulation block 1 303 and simulation block 2 302 on the friction coefficient, this specific embodiment provides multiple groups of simulation block assemblies 3, disassemble and assemble multiple groups of simulation block assemblies 3, repeat the above steps of obtaining the critical sliding force, and calculate the average value X of the friction coefficient of multiple groups. And the standard deviation σ, we get the upper limit deviation = X + 3σ, the lower limit deviation = X - 3σ, and the friction coefficient value range of the bonding surface is X ± 3σ.

[0050] The formula is as follows:

[0051] ,

[0052] Where μ is the friction coefficient of the joint surface, is the critical sliding force borne by the sliding block, is the force applied by the bolt pre-tightening force applying assembly, n is the number of contact surfaces, and in this specific embodiment, n is 2.

[0053] From the above specific embodiments, it can be seen that the present invention has the following beneficial effects:

[0054] 1. By setting up the simulation block assembly 3 to simulate the two parts at the joint surface, and using the bolt preload application assembly 1 to apply the preload force after the bolts are tightened, the actual working conditions of the joint surface can be simulated. Then, based on the test results, the friction coefficient can be accurately calculated, improving the accuracy of the friction coefficient acquisition and preventing the bolt selection from failing to meet the actual working conditions.

[0055] 2. By providing the limit block 8, the simulation block 1 302 and the simulation block 2 303 can be prevented from moving, thereby more accurately simulating the actual working conditions of the joint surface and avoiding affecting the accurate calculation of the friction coefficient of the joint surface;

[0056] 3. Applying pressure to simulate the preload force through the hydraulic cylinder 101 can maintain the stability of the pressure during the test and further improve the accuracy of the friction coefficient.

[0057] 4. The pressure sensor 6 and the display can intuitively monitor the pressure applied by the hydraulic cylinder 101, making it easier to adjust and control;

[0058] 5. By configuring the mounting base 2 as a split, detachable structure, it is easy to transport and install the mounting base 2 to the corresponding test device or test bench;

[0059] 6. The baffle 5 can prevent the pressure sensor 6 from shifting during movement;

[0060] 7. By using the universal testing machine in the prior art to conduct relevant tests, it is convenient to determine the critical slip force, which can save the design and manufacture of the corresponding test device, shorten the manufacturing cycle of the joint surface friction coefficient detection device, and reduce the manufacturing cost.

[0061] The above description of the disclosed embodiments will enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A component simulating a screw joint surface, comprising a mounting seat (2), characterized in that: One end of the mounting seat (2) is provided with a mounting cavity, and a simulation block assembly (3) is provided in the mounting cavity. The simulation block assembly (3) includes a simulation block 1 (303) and a simulation block 2 (302). A sliding block (301) is provided between the simulation block 1 (303) and the simulation block 2 (302). The sliding block (301) is used to withstand a sliding force. Two side surfaces of the sliding block (301) are in contact with the simulation block 1 (303) and the simulation block 2 (302) respectively. The material, surface treatment process and roughness of the sliding block (301) are consistent with those of the joint surface to be measured. The material, surface treatment process and roughness of the simulation block one (303) and the simulation block two (302) are the same as those of another component at the joint surface to be measured, and a bolt preload force applying assembly (1) is provided at the other end of the mounting seat (2). The bolt preload force applying assembly (1) is used to provide a bolt preload force at the joint surface to be measured, and the bolt preload force applying assembly (1) includes a force applying rod (9), the length direction of the force applying rod (9) is perpendicular to the sliding force direction, and the force applying rod (9) can abut against the surface of the simulation block one (303).

2. The component simulating a screw joint according to claim 1, wherein: The upper end of the sliding block (301) extends out of the mounting cavity, and two limiting blocks (8) are arranged on the upper surface of the mounting seat (2) and are located at the edge of the mounting cavity. The limiting blocks (8) can abut against the simulation block 1 (303) or the simulation block 2 (302).

3. The component simulating a screw joint according to claim 2, wherein: The mounting seat (2) comprises an upper mounting plate (203) and a lower mounting plate (201), a mounting block (202) being screwed between the upper mounting plate (203) and the lower mounting plate (201), the mounting cavity being provided in the mounting block (202), the upper mounting plate (203) being provided with a corresponding mounting hole 1, the limiting block (8) being provided at the edge of the mounting hole 1, and the sliding block (301) extending from the mounting hole 1.

4. The component simulating a screw joint according to claim 3, wherein: The bolt pre-tightening force applying assembly (1) comprises a hydraulic cylinder (101), and the hydraulic cylinder (101) is arranged on the lower mounting plate (201).

5. The component simulating a screw joint according to claim 4, wherein: A pressure sensor (6) is connected between the piston rod of the hydraulic cylinder (101) and the force application rod (9), and the pressure sensor (6) is electrically connected to a display.

6. The component simulating a screw joint according to claim 5, wherein: Baffles (5) are respectively provided on the lower mounting plate (201) and located on both sides of the pressure sensor (6).

7. A device for detecting friction coefficient of a joint surface, characterized in that: The invention comprises a component for simulating a screw joint surface as claimed in claim 6, and also comprises a universal testing machine body, wherein the universal testing machine body comprises a supporting platform (11) and a force applying member (10), a clamping seat (12) is provided on the supporting platform (11), and the lower mounting plate (201) is detachably connected to the clamping seat (12).

8. The device for detecting the friction coefficient of a joint surface according to claim 7, wherein: An avoidance groove is provided on one side of the upper end of the sliding block (301).

9. The device for detecting the friction coefficient of a joint surface according to claim 8, wherein: A positioning column (4) is provided at the lower portion of one end of the mounting seat (2) on which the simulation block assembly (3) is mounted, and a positioning hole is provided on the positioning column (4) along its radial direction.

10. The device for detecting the friction coefficient of a joint surface according to claim 9, wherein: A leveling foot (7) is provided at the lower portion of one end of the mounting seat (2) on which the bolt pre-tightening force applying assembly (1) is mounted, and a spirit level is provided on the mounting seat (2).

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