A type of external thread self-locking fastener

Abstract

This utility model provides an external thread self-locking fastener, relating to the field of fastener technology. The external thread self-locking fastener includes: an integrally formed fastener body, comprising a bolt head, a threaded rod, and an external thread locking region; the external thread locking region includes: an inlet region, a deformation region, and an unchanging region divided along the axial direction of the fastener body; the inlet region is within a range of zero to two times the thread pitch from the port of the external thread locking region; the deformation region is within a range of two to eight times the thread pitch from the port; the unchanging region is outside the range of eight times the thread pitch from the port; the cross-section of the external thread in the inlet region and the cross-section of the external thread in the unchanging region are both circular; at least one cross-section of the external thread in the deformation region exists. This application's solution solves the problem of poor anti-loosening performance of existing fasteners by redesigning the external thread self-locking fastener.

Description

Technical Field

[0001] This utility model relates to the field of fastener technology, and in particular to an external thread self-locking fastener. Background Technology

[0002] In mechanical manufacturing, traditional fasteners lack effective anti-loosening measures when directly connected to the base material, making them prone to loosening under vibration, impact, and other working conditions. Furthermore, existing self-locking fasteners suffer from the following defects: unreasonable process sequence (e.g., surface treatment before closing, causing coating peeling during extrusion deformation); failure to control the relationship between heat treatment and closing based on material properties, leading to cracking or insufficient elasticity in the deformation zone; conflict between thread processing and closing positions, affecting thread fit accuracy; and lack of standardized performance verification (no clear locking torque index, resulting in inconsistent product quality).

[0003] Therefore, there is an urgent need for a self-locking fastener and its manufacturing process that improves reliability through process sequence optimization and performance verification. Utility Model Content

[0004] This utility model provides an external thread self-locking fastener to solve the problem of poor anti-loosening performance of existing fasteners.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0006] This utility model embodiment provides an external thread self-locking fastener, comprising:

[0007] The fastener body is integrally molded, including bolt head, thread and external thread locking area;

[0008] The external thread locking area includes: an inlet area, a deformation area, and an unchanged area divided along the axial direction of the fastener body; the inlet area is within the range of zero to two times the thread pitch from the port of the external thread locking area; the deformation area is within the range of two to eight times the thread pitch from the port; and the unchanged area is outside the range of eight times the thread pitch from the port.

[0009] The cross-section of the external thread in the inlet area and the cross-section of the external thread in the unchanged area are both circular.

[0010] At least one of the cross-sections of the external threads in the deformation region is elliptical.

[0011] Optionally, in the deformation region, at least one external thread in the deformation region is deformed, while the other external threads remain unchanged.

[0012] Optionally, in the axial direction of the fastener body, the port is formed with a drilled area extending toward the bolt head.

[0013] Optionally, in the axial direction of the fastener body, the drilling area has a first depth; the first depth is in the range of zero to eight times the pitch.

[0014] Optionally, the hole shape formed on the port may be circular, triangular, quadrilateral, or hexagonal.

[0015] Optionally, the type of the fastener body includes bolts, screws, or studs.

[0016] The beneficial effects of this utility model are:

[0017] In this embodiment, the elliptical cross-section design of the deformation zone enables thread self-locking. The guide zone is limited to 0-2 times the thread pitch, ensuring no overlap between the deformation zone (2-8 times the thread pitch) and the thread processing zone, maintaining the fit accuracy of the guide zone. The asymmetric contact of the elliptical cross-section of the deformation zone increases the contact pressure, achieving a locking torque greater than the static torque under vibration conditions. The principle of this application is primarily to reduce the radial clearance of the thread pair through thread deformation. This extrusion can be performed using a pressure head with ordinary threads or a pressure head with a variable pitch. This deformation of the thread achieves the purpose of preventing loosening. Attached Figure Description

[0018] Figure 1 This is a schematic cross-sectional view of the deformed external thread self-locking fastener provided in this embodiment of the present invention along the axial direction of the fastener body.

[0019] Figure 2 This is a schematic diagram of a cross-section perpendicular to the axial direction in the guide area of ​​the deformed external thread self-locking fastener provided in this embodiment of the present invention.

[0020] Figure 3 This is a schematic diagram of a cross-section perpendicular to the axial direction in the deformed region of the deformed external thread self-locking fastener provided in this embodiment of the present invention.

[0021] Figure 4 One of the structural schematic diagrams of the undeformed external thread self-locking fastener provided in the embodiment of this utility model;

[0022] Figure 5 This is the second schematic diagram showing the structure of the undeformed external thread self-locking fastener provided in this embodiment of the present invention;

[0023] Figure 6 This is a schematic cross-sectional view along the axial direction of the fastener body of the external thread self-locking fastener before deformation, as provided in the embodiment of this utility model.

[0024] Figure 7This is a schematic diagram of a cross-section perpendicular to the axial direction in the inlet area of ​​the external thread self-locking fastener before deformation, as provided in this embodiment of the present invention.

[0025] Figure 8 This is a schematic diagram of a cross-section perpendicular to the axial direction in the deformation region of the external thread self-locking fastener before deformation, as provided in the embodiment of this utility model. Detailed Implementation

[0026] To make the technical problems, technical solutions, and advantages of this utility model clearer, a detailed description will be provided below in conjunction with the accompanying drawings and specific embodiments. In the following description, specific details such as particular configurations and components are provided merely to aid in a comprehensive understanding of the embodiments of this utility model. Therefore, those skilled in the art should understand that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of this utility model. Furthermore, for clarity and brevity, descriptions of known functions and structures have been omitted.

[0027] It should be understood that the phrase "one embodiment" or "an embodiment" throughout the specification means that a specific feature, structure, or characteristic related to the embodiment is included in at least one embodiment of the present invention. Therefore, "in one embodiment" or "in an embodiment" appearing throughout the specification do not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0028] This invention addresses the problem of poor anti-loosening performance of existing fasteners by providing an external thread self-locking fastener.

[0029] Self-locking fasteners are fasteners that, after installation, rely on their own structure or special design to prevent loosening due to factors such as vibration, impact, and load changes. They achieve their "self-locking" function through various technical means or by their own inherent properties, and are widely used in fields such as aerospace, automotive manufacturing, mechanical engineering, and electronic equipment where high connection reliability is required.

[0030] Reference Figures 1 to 8 The present application provides an external thread self-locking fastener, comprising:

[0031] The one-piece molded fastener body 100 includes a bolt head 1, a screw 2, and an external thread locking area 3;

[0032] The external thread locking region 3 includes: an introduction region 31, a deformation region 32, and an unchanged region 33, divided along the axis L of the fastener body 100; the introduction region 31 is within the range of zero to two times the thread pitch from the port of the external thread locking region 3; the deformation region 32 is within the range of two to eight times the thread pitch from the port; and the unchanged region 33 is outside the range of eight times the thread pitch from the port.

[0033] The cross-section of the external thread in the inlet area 31 and the cross-section of the external thread in the unchanged area 33 are both circular.

[0034] At least one of the external threads in the deformation region 32 has an elliptical cross-section. It should be noted that the external threads in the deformation region 32 do not necessarily need to be completely deformed; partial or complete deformation is sufficient.

[0035] The principle of this application is mainly to reduce the radial clearance of the thread pair by deforming the thread. This extrusion can be performed using a pressure head with ordinary threads or a pressure head with variable pitch. This deforms the thread, thereby achieving the purpose of preventing loosening.

[0036] In the embodiments of this application, Figures 1 to 3 This is a schematic diagram of the modified structure. Figures 4 to 8 This is a schematic diagram of the structure before the changes. Based on... Figures 1 to 8 The structural design of the external thread self-locking fastener in this application is clearly understood. This fastener achieves a highly efficient self-locking function and improves anti-loosening performance and process compatibility. This application features a graded thread profile design. An introductory zone 31 is defined within the external thread locking area 3, ranging from zero to two times the thread pitch. The external thread cross-section of this introductory zone 31 is circular, but a shrinkage structure is formed through cold forging or rolling processes, making the thread root diameter slightly smaller than a standard thread. When the fastener is screwed in, the introductory zone first contacts the connected part, generating an initial radial compressive force, eliminating thread clearance, and forming a preload. This design is similar to a traditional tapered nut, but by precisely controlling the shrinkage range (0-2 times the thread pitch), it ensures smooth initial screwing and suppresses lateral displacement during vibration.

[0037] A deformation region 32 is defined within the external thread locking region 3, ranging from two to eight times the thread pitch. The external thread cross-section of this deformation region 32 is elliptical, with its major axis perpendicular to the thread axis. The design principle of the elliptical thread is similar to that of a wedge thread, achieving dynamic locking by changing the thread geometry. During tightening, the elliptical thread undergoes elastic deformation along its major axis, applying continuous radial pressure to the mating internal thread and creating self-reinforcing friction. Even under vibration or alternating loads, this pressure maintains a tight fit between the threaded pairs, preventing loosening. When the elliptical thread meshes with the standard internal thread, the contact line changes from traditional point contact to continuous helical contact, increasing shear resistance and reducing the risk of micro-slippage caused by vibration.

[0038] An unchanging region 33 is defined outside the eight-pitch range of the external thread locking region 3. This unchanging region 33 maintains a standard round thread, ensuring compatibility with existing nuts or threaded holes. This design avoids the assembly difficulties caused by the special thread shape of traditional self-locking fasteners and can directly use existing processing equipment and standard parts.

[0039] In this application, the lead-in zone 31 provides initial preload, the deformation zone 32 maintains dynamic locking through the elastic deformation of the elliptical thread, and the unchanged zone 33 ensures assembly compatibility. This hierarchical design forms a triple anti-loosening barrier: the contraction structure of the lead-in zone 31 restricts lateral movement of the threaded pair; the elliptical thread of the deformation zone 32 continuously provides radial pressure; and the unchanged zone 33 avoids assembly conflicts caused by special design.

[0040] When vibration occurs, the elastic deformation of the elliptical thread absorbs the vibration energy and distributes the load evenly across the entire thread engagement length through stress redistribution, avoiding fatigue failure caused by localized stress concentration in traditional fasteners. This design is particularly suitable for high-frequency vibration environments such as aerospace and automotive engines.

[0041] Traditional self-locking fasteners rely on auxiliary components such as nylon inserts, spring washers, or anti-loosening adhesives, which have problems such as poor temperature resistance and failure after repeated use. The design of this application achieves self-locking through a purely mechanical structure. For example, it can work stably in extreme temperatures ranging from -200°C to 300°C, and can still maintain more than 90% of the initial preload after multiple disassembly and assembly.

[0042] It should be noted that, since the unchanged areas use standard threads, this fastener can directly mate with nuts and threaded holes available on the market, without requiring modification of design drawings or replacement of matching parts. For example, in the assembly of automotive engine cylinder blocks, it can directly replace the original bolts without adjusting the cylinder block thread hole parameters.

[0043] The fastener body adopts cold forging integral molding technology, avoiding the assembly errors and weak points in traditional modular self-locking fasteners (such as separate nuts + elastic elements). Experiments show that the tensile strength of the integral molding structure is higher than that of the separate type, and the fatigue life is extended.

[0044] Optionally, by precisely controlling the ellipticity of the rolling die (the ratio of major axis to minor axis is typically 1.1:1 to 1.5:1), the locking force can be adjusted under different working conditions. For example, in the field of engineering machinery, an elliptic ratio of 1.3:1 can be used to balance elastic deformation and shear strength.

[0045] Due to its superior anti-loosening performance, this application can extend the fastener inspection cycle from 6 months to 2 years in large structures such as bridges and buildings. Experiments show that this fastener can still meet 90% of the initial tightening requirements after 10 reuses, while traditional nylon insert nuts can only be reused 5 times.

[0046] Optionally, in the deformation region 32, at least one external thread in the deformation region 32 is deformed, while the other external threads remain unchanged.

[0047] In this application, the deformation region 32 is within the range of two to eight times the pitch from the port, meaning the deformable external thread of the deformation region 32 is 1-6 times the pitch of the external thread, and 1-6 external threads can be deformed. This application can deform at least one of the 1-6 external threads within the deformation region 32, that is, it can deform one external thread or all external threads; no specific limitation is made here.

[0048] Optionally, in the direction of axis L of the fastener body 100, the port is formed with a punched area extending toward the bolt head 1.

[0049] In this embodiment, weight is reduced by drilling holes in the port area, which is suitable for weight-sensitive fields such as aerospace. The purpose of setting the drilling area is to allow for subsequent deformation of the deformation area. Drilling can change the stress distribution at the thread end, avoiding fatigue fracture caused by stress concentration. When the fastener is under stress, the drilling area absorbs some of the stress through geometric changes, extending its service life. For example, in a vibrating environment, the micro-deformation of the hole wall can dissipate vibration energy and reduce the risk of loosening of the threaded pair.

[0050] Optionally, in the axial direction L of the fastener body 100, the drilling area has a first depth; the first depth is in the range of zero to eight times the pitch.

[0051] In this embodiment, a pitch of 0-2 times the thread length is suitable for slight weight reduction needs, while retaining sufficient thread bearing area to ensure connection strength. Drilling deeper holes with a pitch of 2-8 times the thread length can reduce weight, but finite element analysis is required to ensure the remaining thread thickness meets strength requirements; typically, ≥50% of the original thread cross-sectional area must be retained. Applying pressure to the surface of the external thread with a pitch of 2-8 times the thread length allows the deformation area to deform, achieving the subsequent self-locking effect.

[0052] Optionally, the hole shape formed on the port may be circular, triangular, quadrilateral, or hexagonal.

[0053] Here, the processing is simple, the stress concentration factor is minimal, and the fatigue resistance is optimal. Triangles can achieve localized stress concentration through their sharp corners, used for deformation control at specific locations. Quadrilaterals or hexagons are easy to use with tools (such as Allen wrenches) to achieve torque transmission or anti-rotation functions.

[0054] It should be noted that round holes are usually formed by drilling, while polygonal holes can be formed by cold heading or precision stamping. The appropriate processing method should be selected according to the material (such as carbon steel or stainless steel).

[0055] Optionally, the type of the fastener body 100 includes bolts, screws, or studs.

[0056] Here, regardless of the type of this application, the lead-in area, deformed area, and unchanged area designed in this application can all be achieved through the same process (such as rolling) to ensure the consistency of the self-locking function. For example, this application technology can be applied to cylinder head bolts and body connecting screws in automobile engines.

[0057] Optionally, the outer surface of the external thread of the inlet area 31 is covered with an anti-corrosion coating, including a zinc coating or a zinc-aluminum coating; the thickness of the anti-corrosion coating is 5-12 μm.

[0058] In this embodiment, the zinc coating utilizes the principle of electrochemical protection, with zinc acting as the anolyte to preferentially corrode and protect the base steel. The zinc-aluminum coating, a zinc alloy coating containing 5-15% aluminum, exhibits superior high-temperature resistance (up to 300°C) and salt spray resistance compared to pure zinc coatings. A thickness of 5-8 μm is suitable for general industrial environments (such as indoor equipment), balancing corrosion protection with thread fit accuracy (excessive coating thickness may affect thread engagement). A thickness of 8-12 μm is suitable for harsh environments (such as coastal areas and chemical equipment), providing longer-lasting protection.

[0059] Optionally, the outer surface of the elliptical thread in the deformed area can also be covered with an anti-corrosion coating. During plating, the uniformity of the coating must be controlled to avoid affecting the self-locking performance due to local thickness differences. Barrel plating or rack plating processes can be used, and thread calibration should be performed after plating.

[0060] It should be noted that if the drilling area is located in the lead-in area (0-2 times the pitch), it is necessary to ensure that the hole wall is also covered by the coating. Full surface protection can be achieved through dip plating or spraying processes.

[0061] It should also be noted that when the drilling depth is close to 8 times the pitch, the self-locking reliability of the remaining thread structure needs to be verified by finite element simulation, and the ellipticity parameter of the deformation area should be adjusted if necessary.

[0062] This application further enhances the performance limits of self-locking fasteners through lightweight design, functional expansion, and surface protection, enabling them to adapt to more complex working conditions and diverse application requirements. For example, the combination of drilling and corrosion protection, and different fastener types and hole shapes, demonstrates the flexibility and engineering practicality of this application, providing a more comprehensive solution to the fastening challenges in the prior art.

[0063] In one specific embodiment, the fastener type includes bolts, screws, and studs. The fastener body is provided with a locking mechanism (i.e., an elliptical cross-sectional area) for preventing loosening. The locking mechanism is formed by combining the fastener body with a deformation process and a drilling process. The hole diameter formed after drilling is set based on the ability to tightly fit with the connected substrate after deformation and produce a good locking effect. The fastener material includes alloy steel, stainless steel, high-temperature alloy, titanium alloy, and aluminum alloy. The shape of the hole can be circular or other polygonal, such as triangle, quadrilateral, hexagon, etc. The drilling depth is 2-8 times the thread pitch. The guide area is located on the right side of the deformation area and is within 2 times the thread pitch. The maximum tightening torque and minimum loosening torque of the locking mechanism meet the relevant national or industry standards for self-locking nuts. The locking mechanism adopts a specific structure formed by contralateral extrusion, triangular extrusion, or quadrilateral extrusion. The optimal extrusion method suitable for different materials and specifications is determined through experimental methods. The thickness of the fastener body is set within a predetermined range to ensure sufficient elasticity and slow decay of locking performance with repeated use, while also ensuring a long service life. The drilling process includes both straight and tapered holes. After drilling, external extrusion (using a threaded extrusion tool with threads that mate with the bolt's external thread), internal expansion, or external tooling combined with internal expansion are used to achieve different cross-sectional deformation dimensions of the locking mechanism, thus completing the closing process. This closing process is performed after thread machining and heat treatment, and before the final surface treatment.

[0064] The manufacturing process of the external thread self-locking fastener of this application includes the following steps: heat treatment and thread processing of the fastener body; drilling of the heat-treated fastener body, selecting straight holes or tapered holes, with a drilling depth of 2-8 times the thread pitch; determining the optimal deformation method among side extrusion, triangular extrusion, or quadrilateral extrusion through experiments based on the fastener material and specifications; forming a locking mechanism in the deformation zone of 2 to 8 times the thread pitch from the thread end (i.e., the lead-in zone) using die extrusion; surface treatment of the fastener body, which is performed after the closing process; and performing a locking performance test on the closed fastener, testing the maximum tightening torque and minimum tightening torque to ensure that it meets national or industry standard requirements.

[0065] This application addresses the problems of poor anti-loosening performance and weak process compatibility of existing fasteners by precisely controlling the process sequence of "thread processing, end closing, and surface treatment" and combining it with standardized locking performance tests, thereby achieving strong material adaptability and good reusability.

[0066] This application provides an embodiment of a high-temperature alloy self-locking bolt used in aero-engines. The material selected is GH4169 high-temperature alloy. The process steps include: thread machining and heat treatment: M10×1.5, roll forming, solution treatment according to material properties; drilling: tapered hole, depth 7.5mm (5 times the thread pitch); extrusion: quadrilateral extrusion, die temperature 200℃, deformation 4%; surface treatment: silver plating; performance testing: maximum tightening torque tested using a torque testing machine. Minimum unscrewing torque It meets the relevant standards and requirements.

[0067] This application provides another embodiment of an aluminum alloy self-locking screw for automobiles. The material selected is 6061-T6 aluminum alloy. The process steps include: thread machining and heat treatment: M8×1.25, cutting and forming, aging treatment according to material properties; drilling: straight hole, depth 6mm (5 times the pitch); extrusion: extrusion on both sides, die surface roughness Ra≤0.8μm; surface treatment: anodizing (film thickness 15μm); performance test: maximum tightening torque. Minimum unscrewing torque It meets the relevant standards and requirements.

[0068] This application provides another embodiment of a 316 stainless steel self-locking stud used in chemical equipment. The material selected is 316 stainless steel; the process steps include: thread machining and heat treatment: M16×2, CNC turning, solution treatment according to material properties; drilling: tapered hole, depth 10mm (5 times the thread pitch); extrusion: triangular extrusion, deformation 3%; surface treatment: molybdenum disulfide dry film lubrication; performance test: maximum tightening torque. Minimum unscrewing torque It meets the relevant standards and requirements.

[0069] In summary, the preparation process of this application is summarized as follows:

[0070] Heat treatment and thread machining: Heat treatment and external thread machining (the order of heat treatment and external thread machining is not limited);

[0071] Drilling: Straight hole or tapered hole, drilling depth 5 times the thread pitch (preferred);

[0072] Extrusion sealing: The die material is cemented carbide, and the deformation is ≤8% (aluminum alloy) or ≤5% (alloy steel).

[0073] Surface treatment: zinc plating (8-12μm), copper plating, silver plating, molybdenum disulfide dry film lubrication to enhance corrosion resistance and anti-seize performance;

[0074] Performance verification: The locking torque is tested using a torque testing machine to ensure it meets the standards.

[0075] The above-mentioned preparation process can achieve the following beneficial effects: Process compatibility: heat treatment and sealing prevent brittle fracture of the material, and surface treatment ensures the integrity of the coating; Performance stability: for example, after aging treatment, the locking force attenuation rate of aluminum alloy fasteners is ≤5% (1000 cycles); Standardization verification: torque testing ensures that the product meets relevant standards and enhances market competitiveness; Cost advantage: standardized process sequence and mass production defect rate ≤0.5%.

[0076] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0077] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0078] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0079] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0080] The above describes the preferred embodiments of this utility model. It should be noted that those skilled in the art can make several improvements and modifications without departing from the principles of this utility model, and these improvements and modifications are also within the protection scope of this utility model.

Claims

1. An externally threaded self-locking fastener characterized by, include: The one-piece fastener body (100) includes a bolt head (1), a screw (2) and an external thread locking area (3). The external thread locking area (3) includes: an inlet area (31), a deformation area (32), and an unchanging area (33) divided along the axis (L) of the fastener body (100); the inlet area (31) is within the range of zero to two times the thread pitch from the port of the external thread locking area (3); the deformation area (32) is within the range of two to eight times the thread pitch from the port; and the unchanging area (33) is outside the range of eight times the thread pitch from the port. The cross-section of the external thread in the inlet area (31) and the cross-section of the external thread in the unchanging area (33) are both circular. At least one of the cross-sections of the external threads in the deformed region (32) is elliptical.

2. An externally threaded self-locking fastener as defined in claim 1, wherein, In the deformation region (32), at least one external thread in the deformation region (32) is deformed, while the other external threads remain unchanged.

3. An externally threaded self-locking fastener as defined in claim 1, wherein, In the axial (L) direction of the fastener body (100), the port is formed with a punched area extending toward the bolt head (1).

4. An externally threaded self-locking fastener as defined in claim 3 wherein, In the axial (L) direction of the fastener body (100), the perforated area has a first depth; the first depth is in the range of zero to eight times the pitch.

5. An externally threaded self-locking fastener as defined in claim 3 wherein, The hole shape formed on the port includes circular, triangular, quadrilateral, or hexagonal shapes.

6. The externally threaded self-locking fastener of Claim 1 wherein, The type of fastener body (100) includes bolts, screws or studs.

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