Bolt stretching tool

Abstract

The utility model discloses a bolt stretching tool which comprises a body connected with a bolt, the body is provided with a threaded hole connected with the bolt in a matched mode, a positioning part is arranged below the body and arranged outside the bolt in a sleeving mode, a driving part is arranged above the body, and a connecting assembly is arranged between the driving part and the body. The driving part drives the connecting assembly to drive the body to move in the vertical direction so that the bolt connected with the body can be stretched in the vertical direction. According to the scheme, the body is positioned and supported through the positioning part, the bolt is sleeved with the positioning part, the body is connected with the bolt and gradually moves to abut against the positioning part, the driving part vertically moves the body through the connecting assembly, the body abuts against the positioning part while being connected with the bolt, and the bolt is stretched under the counter-acting force. The driving part, the body and the positioning part are arranged from top to bottom, the structure is compact, the installation requirement space is small, the device can adapt to bolt stretching operation in multiple scenes, the application range is wide, and installation is convenient.

Description

Technical Field

[0001] This application belongs to the field of engine auxiliary tooling, specifically relating to a bolt tensioning tooling. Background Technology

[0002] In the design and assembly of large-bore engines, due to the large tightening torque of engine components, conventional wrenches cannot directly apply the pre-tightening force or torque by rotating and engaging the nut. Instead, the operation of first stretching the bolt to the specified deformation and then using the nut to tighten it is often used to achieve the preset tightening pressure on each connection surface.

[0003] By directly stretching the bolt, axial deformation and axial force are first generated, and then the deformation is locked using a nut or other methods to achieve the fastening of the connector. When the bolt is pressurized, the tensile force it experiences exceeds the relaxation and shear forces, thereby fixing the connector together. This method is suitable for situations where large measurable forces and dynamic loads are applied to the connector.

[0004] The bolt stretching process requires specialized bolt stretching equipment. Existing technologies use hydraulic equipment and appropriate tooling and methods to stretch the bolt to a certain length, ensuring the bolt reaches its preset axial force before tightening with a nut. However, using hydraulic stretching for pre-tightening tooling requires a hydraulic pump, resulting in a large overall size, making it inconvenient to operate in confined spaces, limiting the tooling's applicability, and reducing its efficiency in bolt stretching. Utility Model Content

[0005] This application provides a bolt stretching fixture that can adapt to bolt stretching work in different scenarios.

[0006] The technical solution adopted in this application is as follows:

[0007] A bolt stretching fixture includes a body connected to a bolt, the body having a threaded hole that mates with the bolt, a positioning part located below the body and fitted onto the outside of the bolt, a driving part located above the body, and a connecting assembly between the driving part and the body, wherein the driving part drives the connecting assembly to move the body vertically so that the bolt connected to the body is stretched vertically.

[0008] This application also includes the following additional technical features:

[0009] The driving unit includes a driving gear and a driven gear that is connected to the driving gear in a transmission manner. The connecting assembly includes a driven bolt that is connected to the body. A fastener is provided between the driven gear and the driven bolt. The driven gear drives the fastener to tighten the driven bolt.

[0010] The main body has a mounting hole, the driven bolt is located in the mounting hole, one end of the fastener is fixed to the connecting shaft of the driven gear, and the other end of the connecting shaft is aligned and engaged with the top of the driven bolt. The driven bolt is an internal hexagon bolt, and the connecting shaft is an internal hexagon shaft adapted to the internal hexagon bolt.

[0011] The drive unit also includes a fixed support frame, and both the drive gear and the driven gear are located on the fixed support frame, with the axis of the drive gear coinciding with the axis of the fixed support frame.

[0012] The fixed support frame is provided with a connecting hole that aligns with the driven bolt, and the connecting shaft passes through the connecting hole and is aligned with the top of the driven bolt.

[0013] Multiple driven gears are provided along the circumference of the driving gear, and each driven gear meshes with the driving gear for transmission.

[0014] The bolt is provided with a nut on the outside, and the positioning part includes a pad that is sleeved on the outside of the nut. The pad has a through hole for the bolt and the nut to pass through, and the side wall of the pad has an operating hole for the nut to be exposed.

[0015] The operating holes are provided in multiple ways.

[0016] The pad has the same diameter as the body.

[0017] Due to the adoption of the above technical solution, the beneficial effects achieved by this application are as follows:

[0018] (1) The solution of this application uses a positioning part to position and support the body. First, the positioning part is sleeved on the outside of the bolt. The body and the bolt are connected and gradually moved to abut against the positioning part. The drive part moves the body vertically through the connecting component. At the same time, the body and the bolt are connected and abut against the positioning part. The bolt is stretched by the reaction force. The drive part, the body and the positioning part are arranged from top to bottom. The drive part is directly set in the tooling itself to drive the body. The overall structure is compact and does not require external hydraulic equipment for driving. The installation space requirement is small. It can adapt to bolt stretching operations in multiple scenarios. It has a wide range of applications and is easy to install and carry.

[0019] (2) The drive unit of this application includes a drive gear and a driven gear. By setting a driven bolt, the pressure on the body is applied by the gear rotation driving the fastener to tighten the driven bolt. There is no need to connect to hydraulic equipment, the required assembly space is small, the installation is convenient, and it is beneficial to improve the bolt tensioning efficiency.

[0020] (3) In this application, a connecting shaft is set to drive the driven bolt to rotate. The driving gear drives the driven gear meshing with it to rotate. The connecting shaft connected to the driven gear rotates with the driven gear, thereby driving the driven bolt that is engaged with it to rotate and tighten. Under the pressure of the driven bolt, the positioning part presses against the mounting bottom surface. The body drives the bolt to move upward through the reaction force, so that the bolt generates axial deformation and axial force to achieve the predetermined deformation.

[0021] (4) The positioning part is equipped with a pad, and the pad has an operating hole so that the nut on the outside of the bolt is exposed. The nut usually has a tapered hole for disassembly. When the bolt is stretched, the nut is locked by inserting through the operating hole to achieve pre-tightening of the bolt. Attached Figure Description

[0022] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0023] Figure 1 This is a schematic diagram of the structure of the stretching tool in one embodiment of the present invention;

[0024] Figure 2 This is a cross-sectional view of the stretching fixture in one embodiment of the present invention;

[0025] Figure 3 This is a top view of the stretching fixture in one embodiment of the present invention;

[0026] Figure 4 This is a side view of the stretching fixture in one embodiment of the present invention;

[0027] Figure 5 This is an assembly diagram of the stretching fixture in one embodiment of the present invention.

[0028] Explanation of reference numerals in the attached figures:

[0029] 1- Bolt, 11- Nut;

[0030] 2-Body, 21-Mounting holes;

[0031] 3-Drive unit, 31-Drive gear, 32-Driven gear, 33-Driven bolt, 34-Connecting shaft;

[0032] 4-Positioning part, 41-Padded block, 42-Through hole, 43-Operating hole;

[0033] 5-Fixed support frame. Detailed Implementation

[0034] To more clearly illustrate the overall concept of this application, a detailed explanation is provided below with reference to the accompanying drawings.

[0035] Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application may also be implemented in other ways different from those described herein. Therefore, the scope of protection of this application is not limited to the specific embodiments disclosed below. It should be noted that, unless otherwise specified, the embodiments of this application and the features thereof can be combined with each other.

[0036] Furthermore, it should be understood in the description of this application that the terms "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application 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, and therefore should not be construed as a limitation of this application.

[0037] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," 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 communication connection; 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 application according to the specific circumstances.

[0038] In this application, unless otherwise expressly specified and limited, the "above" or "below" of the second feature can mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. In the description of this specification, references to terms such as "an embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described can be combined in any suitable manner in one or more embodiments or examples.

[0039] This application provides a bolt tensioning fixture, such as... Figures 1 to 5As shown, the device includes a body 2 connected to a bolt 1. The body 2 has a threaded hole that engages with the bolt 1. A positioning part 4 is provided below the body 2 and is sleeved on the outside of the bolt 1. A driving part 3 is provided above the body 2. A connecting assembly is provided between the driving part 3 and the body 2. The driving part 3 drives the connecting assembly to move the body 2 vertically so that the bolt 1 connected to the body 2 is stretched vertically.

[0040] This application's solution uses a positioning part 4 to position and support the body 2. The positioning part 4 is first fitted onto the outside of the bolt 1. The body 2, connected to the bolt 1, gradually moves until it abuts against the positioning part 4. The drive part 3 moves the body 2 vertically via a connecting assembly. Simultaneously, the body 2 abuts against the positioning part 4 while connecting to the bolt 1. As the drive part 3 applies downward pressure to the connecting assembly, the body 2 experiences a reaction force that causes the bolt 1 to move upward, achieving tension. The drive part 3, body 2, and positioning part 4 are arranged from top to bottom. The drive part 3 is directly installed within the tooling itself, resulting in a compact overall structure. It eliminates the need for external hydraulic equipment, requires minimal installation space, and can adapt to bolt 1 tensioning operations in various scenarios, offering wide applicability and convenient installation.

[0041] In one embodiment, such as Figure 2 As shown, the drive unit 3 includes a drive gear 31 and a driven gear 32 that is connected to the drive gear 31 in a transmission manner. The connecting assembly includes a driven bolt 33 that is connected to the body 2. A fastener is provided between the driven gear 32 and the driven bolt 33. The driven gear 32 drives the fastener to tighten the driven bolt 33.

[0042] This application sets the drive unit 3 to include a drive gear 31 and a driven gear 32, and applies pressure to the body 2 by means of a driven bolt 33, which is driven by the rotation of the gear to tighten the driven bolt 33. This eliminates the need for hydraulic equipment, requires less assembly space, is easy to install, and helps improve the tensioning efficiency of the bolt 1.

[0043] It should be noted that, in application, the device of this application can drive the drive gear 31 to rotate by means of a torque multiplier.

[0044] Furthermore, the body 2 is provided with a mounting hole 21, the driven bolt 33 is located in the mounting hole 21, one end of the fastener is fixed to the connecting shaft 34 of the driven gear 32, and the other end of the connecting shaft 34 is aligned and engaged with the top of the driven bolt 33.

[0045] In this application, a connecting shaft 34 drives the driven bolt 33 to rotate. The driving gear 31 drives the driven gear 32 meshing with it to rotate. The connecting shaft 34 connected to the driven gear 32 rotates with the driven gear 32, thereby driving the driven bolt 33, which is engaged with it, to rotate and tighten. Under the pressure of the driven bolt 33, the positioning part 4 presses against the mounting bottom surface. The body 2 drives the bolt 1 to move upward through the reaction force, so that the bolt 1 generates axial deformation and axial force to achieve the predetermined deformation.

[0046] It should be noted that the mounting hole 21 is provided with a thread that mates with the driven bolt 33. The mounting hole 21 extends from top to bottom through the body 2. When the driven bolt 33 is tightened, its bottom abuts against the top surface of the positioning part 4.

[0047] Preferably, the driven bolt 33 is a hex socket head cap screw 1, and the connecting shaft 34 is a hex socket head cap shaft adapted to the hex socket head cap screw 1. It can be understood that the hex socket head cap shaft in this embodiment is similar to an hex socket wrench. After engaging with the hex socket on the top of the driven bolt 33, it tightens the bolt 1 as it rotates.

[0048] In one embodiment, such as Figures 1 to 5 As shown, the drive unit 3 also includes a fixed support frame 5, and both the drive gear 31 and the driven gear 32 are located on the fixed support frame 5, and the axis of the drive gear 31 coincides with the axis of the fixed support frame 5.

[0049] By setting a fixed support frame 5 to support and install the drive gear 31 and the driven gear 32, a drive disk is formed, and the drive part 3 is formed as a whole, so as to avoid the drive gear 31 tilting when a force is applied to the drive gear 31.

[0050] Furthermore, the fixed support frame 5 is provided with a connecting hole (not shown in the figure) that aligns with the driven bolt 33. The connecting shaft 34 passes through the connecting hole and is aligned with the top of the driven bolt 33. It can be understood that the connecting hole is used for limiting the assembly of the driven gear, and it corresponds one-to-one with the mounting hole 21 provided on the body 2, so that the connecting shaft 34 connecting the driven gear 32 corresponds one-to-one with the driven bolt 33.

[0051] Preferably, multiple driven gears 32 are provided around the drive gear 31, and each driven gear 32 meshes with the drive gear 31 for transmission.

[0052] In one specific implementation, six driven gears 32 are evenly spaced around the drive gear 31 and mesh with it. At the same time, six fasteners and driven bolts 33 are aligned. The drive gear 31 forms a drive disk with the fixed support frame 5 as the fixed core. Its rotation drives the six driven gears 32 at the same time. The driven bolts 33 are rotated at the same time by the fasteners installed at the driven bolts 33, so as to maintain the force balance of each driven bolt 33.

[0053] In one embodiment, a nut 11 is provided on the outside of the bolt 1, and the positioning part 4 includes a pad 41 sleeved on the outside of the nut 11. The pad 41 is provided with a through hole 42 for the bolt 1 and the nut 11 to pass through, and the side wall of the pad 41 is provided with an operating hole 43 for the nut 11 to be exposed.

[0054] The positioning part 4 is provided with a pad 41, and the pad 41 has an operating hole 43, so that the nut 11 on the outside of the bolt 1 is exposed. The side of the nut 11 usually has a tapered hole for disassembly. When the bolt 1 is stretched, the nut 11 is locked by inserting through the operating hole 43, thereby achieving pre-tightening of the bolt 1.

[0055] Preferably, multiple operating holes 43 are provided. These multiple operating holes 43 are evenly spaced around the sidewall of the pad 41, allowing the nut 11 to be tightened or loosened directly through the operating holes 43 at different angles, thus improving work efficiency.

[0056] In one embodiment, the pad 41 has the same diameter as the body 2. This helps ensure the accuracy of the body 2's position during installation and operation, thereby ensuring accurate force direction on the body 2 and bolt 1, and accurate tensile deformation of bolt 1.

[0057] It is understandable that before stretching bolt 1, its stretching value needs to be preset. The present application also includes a method for calculating the stretching value of bolt 1. The stretching value of bolt 1 is calculated by the formula: δ=F2*C / (M*σ), where: δ is the stretching value of bolt 1, F is the torque of driven bolt 33, C is the stretching length of bolt 1, M is the cross-sectional area of ​​bolt 1, and σ is the yield strength of bolt 1 material.

[0058] When using the device of this application, the tension of bolt 1 is calculated using the above formula. First, the pad 41 of the positioning part 4 is placed in the operating position. During this process, bolt 1 and nut 11 pass through the through hole 42, and the bottom of pad 41 abuts against the operating surface. The tapered hole on the outside of nut 11 is exposed at the operating hole 43. Then, the body 2 is threadedly connected to bolt 1, so that the bottom surface of the body 2 abuts against the top surface of pad 41. During this process, driven bolt 33 can be placed in the mounting hole 21 in advance. The fastener and driven bolt 33 are aligned. Drive gear 31 and driven gear 32 are pre-installed on the fixed support frame 5. The torque multiplier is used. The drive gear 31 is driven to rotate, which in turn drives the driven gear 32 to rotate, thereby causing the fastener to tighten the driven bolt 33. The driven bolt 33 is threadedly connected to the body 2. During the tightening process, the driven bolt 33 moves down to the top surface of the abutment pad 41, and the tightening force is continued to be applied to the driven bolt 33, so that the body 2 connected to it is subjected to a reaction force, which drives the bolt 1 connected to the body 2 to move up, thereby stretching the bolt 1. Then, the nut 11 can be directly adjusted through the gap at the operating hole 43 to complete the pre-tightening of the stretched bolt 1.

[0059] For any parts not mentioned in this application, existing technologies may be used or referenced.

[0060] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

[0061] The above description is merely an embodiment of this application and is not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A bolt tensioning fixture, characterized in that, The device includes a body (2) connected to a bolt (1), the body (2) having a threaded hole that engages with the bolt (1), a positioning part (4) located below the body (2) and fitted around the bolt (1), a driving part (3) located above the body (2), a connecting assembly between the driving part (3) and the body (2), and the driving part (3) driving the connecting assembly to move the body (2) vertically so that the bolt (1) connected to the body (2) is stretched vertically.

2. The bolt tensioning fixture according to claim 1, characterized in that, The drive unit (3) includes a drive gear (31) and a driven gear (32) that is connected to the drive gear (31). The connection assembly includes a driven bolt (33) that is connected to the body (2). A fastener is provided between the driven gear (32) and the driven bolt (33). The driven gear (32) drives the fastener to tighten the driven bolt (33).

3. The bolt tensioning fixture according to claim 2, characterized in that, The body (2) is provided with a mounting hole (21), the driven bolt (33) is located in the mounting hole (21), one end of the fastener is fixed to the connecting shaft (34) of the driven gear (32), and the other end of the connecting shaft (34) is aligned and engaged with the top of the driven bolt (33).

4. The bolt tensioning fixture according to claim 3, characterized in that, The driven bolt (33) is an internal hex bolt (1), and the connecting shaft (34) is an internal hex bolt shaft adapted to the internal hex bolt (1).

5. The bolt tensioning fixture according to claim 3, characterized in that, The drive unit (3) also includes a fixed support frame (5), the drive gear (31) and the driven gear (32) are both located on the fixed support frame (5), and the axis of the drive gear (31) coincides with the axis of the fixed support frame (5).

6. The bolt tensioning fixture according to claim 5, characterized in that, The fixed support frame (5) is provided with a connecting hole that aligns with the driven bolt (33), and the connecting shaft (34) passes through the connecting hole and is aligned with the top of the driven bolt (33).

7. The bolt tensioning fixture according to claim 2, characterized in that, Multiple driven gears (32) are provided along the circumference of the driving gear (31), and each driven gear (32) meshes with the driving gear (31) for transmission.

8. The bolt tensioning fixture according to claim 1, characterized in that, The bolt (1) is provided with a nut (11) on the outside. The positioning part (4) includes a pad (41) sleeved on the outside of the nut (11). The pad (41) is provided with a through hole (42) through which the bolt (1) and the nut (11) pass. The side wall of the pad (41) is provided with an operating hole (43) for the nut (11) to be exposed.

9. The bolt tensioning fixture according to claim 8, characterized in that, The operation hole (43) is provided in multiple places.

10. The bolt tensioning fixture according to claim 8, characterized in that, The pad (41) has the same diameter as the body (2).

Images