Bolt fastening tool and method

Abstract

The invention relates to the technical field of bolt fastening, in particular to a bolt fastening tool and method.The bolt fastening tool comprises a framework unit, a bolt unit horizontally moving along the framework unit, a nut unit, an alignment unit and a tensioning unit; the alignment unit is arranged between the bolt unit and the nut unit. The tool has the beneficial effects that firstly, the tool can flexibly linearly move and circumferentially rotate through the cooperation of the three-petal-shaped overall structure and the opening and closing function of the hydraulic cylinder, and the tool can adapt to different working environments and position requirements; secondly, the locking piece ensures the stability of the bolt in the connecting process, and the connecting precision and reliability are improved; and finally, through cooperative work of the tensioner and the claw mechanism, the pre-tightening force of the bolt is ensured, correct fixing of the flange is also ensured, and therefore the efficiency and safety of the whole fastening process are improved.

Description

Technical Field

[0001] The invention relates to the technical field of bolt fastening, in particular to a bolt fastening tool and a method. Background Art

[0002] In the field of power transmission, especially in live working environments with voltage levels of 35KV and below, the tightening of bolts and nuts is crucial. Traditional bolt tightening methods have many technical challenges in high-voltage operations, such as large alignment errors, high risk of connection failure, low operating efficiency, and safety hazards. These challenges not only affect the success rate of the operation, but may also cause equipment damage and personal safety accidents. Summary of the invention

[0003] In view of the above problems or problems existing in the prior art, the present invention is proposed.

[0004] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0005] In a first aspect, the present invention provides the following technical solutions: a bolt tightening tool, comprising a skeleton unit, a bolt unit horizontally movable along the skeleton unit, a nut unit, an alignment unit, and a tensioning unit;

[0006] The aligning unit is disposed between the bolt unit and the nut unit.

[0007] As a preferred solution of the bolt tightening tool of the present invention, the skeleton unit includes a pipeline and a linear guide rail arranged parallel to the pipeline.

[0008] As a preferred solution of the bolt fastening tool of the present invention, the bolt unit includes a first ring gear guide rail connected to the linear guide rail, a first ring gear rotating circumferentially along the first ring gear guide rail, and a bolt assembly driven to rotate by the first ring gear.

[0009] As a preferred solution of the bolt tightening tool of the present invention, the nut unit includes a second ring gear guide rail connected to the linear guide rail, a second ring gear rotating circumferentially along the second ring gear guide rail, and a nut assembly driven to rotate by the second ring gear.

[0010] As a preferred solution of the bolt fastening tool of the present invention, the overall structure of the bolt assembly and the nut assembly is a three-petal structure.

[0011] As a preferred solution of the bolt fastening tool of the present invention, the bolt assembly includes a bolt first-petal fixing plate connected to the first ring gear, two first hydraulic cylinders connected to the bolt first-petal fixing plate at one end, a bolt second-petal rotating plate and a bolt third-petal rotating plate connected to the output ends of the two first hydraulic cylinders, and a bolt locking member arranged on the bolt first-petal fixing plate, the bolt second-petal rotating plate and the bolt third-petal rotating plate, wherein the bolt first-petal fixing plate, the bolt second-petal rotating plate and the bolt third-petal rotating plate are closed to form an opening, and the cross-sectional size of the opening is adapted to the cross-sectional size of the pipeline;

[0012] One end of the second-petal rotating plate of the bolt and one end of the third-petal rotating plate of the bolt are respectively rotatably connected to the first-petal fixing plate of the bolt.

[0013] As a preferred solution of the bolt fastening tool of the present invention, the nut assembly includes a nut first-petal fixing plate connected to a second ring gear, two second hydraulic cylinders connected to the nut first-petal fixing plate at one end, a nut second-petal rotating plate and a nut third-petal rotating plate connected to the output ends of the two second hydraulic cylinders, and a nut sleeve arranged on the nut first-petal fixing plate, the nut second-petal rotating plate and the nut third-petal rotating plate, wherein the nut first-petal fixing plate, the nut second-petal rotating plate and the nut third-petal rotating plate are closed to form an opening, and the cross-sectional size of the opening is adapted to the cross-sectional size of the pipeline;

[0014] One end of the second-lobe rotating plate of the nut and one end of the third-lobe rotating plate of the nut are respectively rotatably connected to the first-lobe fixing plate of the nut.

[0015] As a preferred solution of the bolt tightening tool of the present invention, wherein: the alignment unit comprises a claw mechanism that moves horizontally along a linear guide rail, and a flange that is sleeved on the pipeline;

[0016] The claw mechanism is used to fix the flange.

[0017] As a preferred solution of the bolt tightening tool of the present invention, it further comprises a control panel for controlling the first hydraulic cylinder and the second hydraulic cylinder.

[0018] In a second aspect, the present invention provides the following technical solutions: a bolt tightening method, comprising defining a coordinate system using a Denavit-Hartenberg method (DH method), and calculating a position error and an angular error between a bolt tip and a nut sleeve end;

[0019] Alignment is performed by adjusting the position and angle of the parts in the bolt unit and the nut unit;

[0020] Use the tensioning unit to stretch the bolt.

[0021] The beneficial effects of the present invention are as follows: on the one hand, the three-petal overall structure cooperates with the opening and closing function of the hydraulic cylinder, so that the tool can flexibly perform linear movement and circumferential rotation to adapt to different working environments and position requirements; secondly, the locking piece ensures the stability of the bolt during the connection process, and improves the accuracy and reliability of the connection; finally, the coordinated work of the tensioner and the claw mechanism not only ensures the preload force of the bolt, but also ensures the correct fixation of the flange, thereby improving the efficiency and safety of the entire tightening process; on the other hand, by adopting the coordinate system defined by the Denavit-Hartenberg method (DH method), the position error and angular error between the bolt tip and the nut sleeve end are accurately calculated, thereby achieving a significant improvement in the alignment accuracy of the bolt and the nut. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. 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 creative work. Among them:

[0023] Figure 1 The overall structure of the bolt tightening tool is shown in Figure 1. Figure 1 .

[0024] Figure 2 The overall structure of the bolt tightening tool is shown in Figure 1. Figure 2 .

[0025] Figure 3 This is a schematic diagram of the bolt unit in the closed state.

[0026] Figure 4 Open the status diagram for the bolt element.

[0027] Figure 5 This is a schematic diagram of the nut unit in the closed state.

[0028] Figure 6 Open the status diagram for the nut unit.

[0029] Figure 7 The figure is a flowchart of the bolt tightening method.

[0030] Figure 8 Create a schematic diagram for the coordinate system. DETAILED DESCRIPTION

[0031] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0032] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0033] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0034] Example 1

[0035] Reference Figure 1 , which is the first embodiment of the present invention, provides a bolt fastening tool, which includes a skeleton unit 100, a bolt unit 200 horizontally moving along the skeleton unit 100, a nut unit 300, an alignment unit 400 and a tensioning unit 500, wherein the bolt unit 200 is provided with a plurality of bolt parts, the nut unit 300 is provided with a plurality of nut parts, and the tensioning unit 500 is provided with a tensioner;

[0036] The aligning unit 400 is disposed between the bolt unit 200 and the nut unit 300 .

[0037] It should be noted that the bolt unit 200 and the nut unit 300 move horizontally along the skeleton unit 100, and the bolt unit 200 passes the bolt through the alignment unit 400 to dock with the nut on the nut unit 300, and the bolt is stretched by the tensioning unit 500 to ensure sufficient pre-tightening force.

[0038] Furthermore, the skeleton unit 100 includes a pipe 101 and a linear guide rail 102 arranged parallel to the pipe 101 .

[0039] It should be noted that the bolt unit 200 , the nut unit 300 , the alignment unit 400 and the tensioning unit 500 are respectively sleeved on the pipe 101 , and move linearly along the linear guide rail 102 .

[0040] When in use, the bolt unit 200 with the bolt and the nut unit 300 with the nut move horizontally along the linear guide rail 102. Furthermore, after the bolt passes through the alignment unit 400 and is connected with the nut, the bolt is stretched by the tensioning unit 500 to ensure sufficient pre-tightening force.

[0041] In summary, the beneficial effect of a bolt tightening tool of the present invention is that by providing a movable bolt unit 200, a nut unit 300 and an alignment unit 400, the docking efficiency of the bolt and the nut can be improved, and further, through the cooperation of the alignment unit 400 and the tensioning unit 500, the pre-tightening force of the bolt can be ensured, thereby improving the efficiency and safety of the entire tightening process.

[0042] Example 2

[0043] Reference Figure 2 to Figure 6 , which is a second embodiment of the present invention, provides a bolt fastening tool, which includes a skeleton unit 100, a bolt unit 200 horizontally moving along the skeleton unit 100, a nut unit 300, an alignment unit 400 and a tensioning unit 500, wherein the bolt unit 200 is provided with a plurality of bolt parts, the nut unit 300 is provided with a plurality of nut parts, and the tensioning unit 500 is provided with a tensioner;

[0044] The aligning unit 400 is disposed between the bolt unit 200 and the nut unit 300 .

[0045] It should be noted that the bolt unit 200 and the nut unit 300 move horizontally along the skeleton unit 100, and the bolt unit 200 passes the bolt through the alignment unit 400 to dock with the nut on the nut unit 300, and the bolt is stretched by the tensioning unit 500 to ensure sufficient pre-tightening force.

[0046] Furthermore, the skeleton unit 100 includes a pipe 101 and a linear guide rail 102 arranged parallel to the pipe 101 .

[0047] Furthermore, the bolt unit 200 includes a first ring gear 202 guide rail 201 connected to the linear guide rail 102, a first ring gear 202 rotating circumferentially along the first ring gear 202 guide rail 201, and a bolt assembly 203 driven to rotate by the first ring gear 202, wherein the bolt assembly 203 is provided with bolts.

[0048] It should be noted that the first ring gear 202 guide rail 201 moves linearly along the linear guide rail 102, driving the first ring gear 202 and the bolt assembly 203 to move linearly along the linear guide rail 102. Furthermore, the first ring gear 202 can rotate circumferentially along the first ring gear 202 guide rail 201, further driving the bolt assembly 203 to rotate circumferentially.

[0049] Furthermore, the nut unit 300 includes a second ring gear 302 guide rail 301 connected to the linear guide rail 102, a second ring gear 302 rotating circumferentially along the second ring gear 302 guide rail 301, and a nut assembly 303 driven to rotate by the second ring gear 302, wherein a nut is provided on the nut assembly 303.

[0050] It should be noted that the second ring gear 302 guide rail 301 moves linearly along the linear guide rail 102, driving the second ring gear 302 and the nut assembly 303 to move linearly along the linear guide rail 102. Furthermore, the second ring gear 302 can rotate circumferentially along the second ring gear 302 guide rail 301, further driving the nut assembly 303 to rotate circumferentially.

[0051] Furthermore, the overall structure of the bolt assembly 203 and the nut assembly 303 is a three-petal structure.

[0052] Preferably, the three-petal structure allows the tool to flexibly perform linear movement and circumferential rotation to adapt to different working environments and position requirements.

[0053] Further, the bolt assembly 203 includes a bolt first-flap fixing plate 203a connected to the first ring gear 202, two first hydraulic cylinders 203b connected to the bolt first-flap fixing plate 203a at one end, a bolt second-flap rotating plate 203c and a bolt third-flap rotating plate 203d connected to the output ends of the two first hydraulic cylinders 203b, and a bolt locking member 203e arranged on the bolt first-flap fixing plate 203a, the bolt second-flap rotating plate 203c and the bolt third-flap rotating plate 203d, wherein the bolt first-flap fixing plate 203a, the bolt second-flap rotating plate 203c and the bolt third-flap rotating plate 203d are closed to form an opening, and the cross-sectional size of the opening is adapted to the cross-sectional size of the pipeline 101;

[0054] It should be noted that the locking member includes a bolt fixing sleeve and a spring-loaded claw or pin to fix the bolt, and also includes a driving member (not shown in the accompanying drawings). When the bolt is correctly guided to the position, these claws or pins will automatically extend and clamp the bolt to ensure that it remains stable during the connection process. Once the bolt and nut are successfully connected, the driving member (such as a hydraulic cylinder or an electric motor) will act on the bolt locking member 203e to retract the claws or pin, thereby releasing the bolt and allowing it to move freely.

[0055] Preferably, the locking piece can ensure the stability of the bolt during the connection process, thereby improving the accuracy and reliability of the connection.

[0056] One end of the second-petal rotating plate 203c of the bolt and one end of the third-petal rotating plate 203d of the bolt are respectively rotationally connected to the first-petal fixing plate 203a of the bolt, wherein the end of the second-petal rotating plate 203c of the bolt rotationally connected to the first-petal fixing plate 203a of the bolt is the same end as the end of the second-petal rotating plate 203c of the bolt connected to the first hydraulic cylinder 203b; the end of the third-petal rotating plate 203d of the bolt rotationally connected to the first-petal fixing plate 203a of the bolt is the same end as the end of the third-petal rotating plate 203d of the bolt connected to the first hydraulic cylinder 203b.

[0057] It should be noted that the two first hydraulic cylinders 203b are respectively used to drive the bolt second petal rotating plate 203c and the bolt third petal rotating plate 203d to open or close.

[0058] Further, the nut assembly 303 includes a nut first-lobe fixing plate 303a connected to the second ring gear 302, two second hydraulic cylinders 303b connected to the nut first-lobe fixing plate 303a at one end, a nut second-lobe rotating plate 303c and a nut third-lobe rotating plate 303d connected to the output ends of the two second hydraulic cylinders 303b, and a nut sleeve 303e arranged on the nut first-lobe fixing plate 303a, the nut second-lobe rotating plate 303c and the nut third-lobe rotating plate 303d, wherein the nut first-lobe fixing plate 303a, the nut second-lobe rotating plate 303c and the nut third-lobe rotating plate 303d are closed to form an opening, the cross-sectional size of the opening is adapted to the cross-sectional size of the pipeline 101, and a nut is arranged in the nut sleeve 303e;

[0059] One end of the nut second lobe rotating plate 303c and the nut third lobe rotating plate 303d are respectively rotatably connected to the nut first lobe fixing plate 303a, wherein the end of the nut second lobe rotating plate 303c rotatably connected to the nut first lobe fixing plate 303a is the same end as the end of the nut second lobe rotating plate 303c connected to the second hydraulic cylinder 303b; the end of the nut third lobe rotating plate 303d rotatably connected to the nut first lobe fixing plate 303a is the same end as the end of the nut third lobe rotating plate 303d connected to the second hydraulic cylinder 303b.

[0060] It should be noted that the two second hydraulic cylinders 303b are respectively used to drive the nut second petal rotating plate 303c and the nut third petal rotating plate 303d to open or close.

[0061] Preferably, the position and angle adjustability of the nut enhances the adaptability of the tool to nuts of different specifications.

[0062] Furthermore, the alignment unit 400 includes a claw mechanism 401 that moves horizontally along the linear guide rail 102 , and a flange 402 that is sleeved on the pipe 101 ;

[0063] The claw mechanism 401 is used to fix the flange 402 .

[0064] It should be noted that the flange 402 is used as a connecting piece to fix the bolts and nuts in the correct position. During the tightening process, the flange 402 ensures that the bolts and nuts are aligned and maintain the correct relative position. Further, the claw mechanism 401 is used to accurately position the flange 402 during the tightening process to ensure that the flange 402 does not move or deviate during the tightening process.

[0065] Preferably, the flange 402 is fixed by the claw mechanism 401, which enhances the stability of the entire connection, especially in a dynamic or load-changing environment.

[0066] Furthermore, it also includes a control panel 600 for controlling the first hydraulic cylinder 203b and the second hydraulic cylinder 303b.

[0067] When in use, the bolt unit 200 and the nut unit 300 can respectively move linearly along the linear guide rail 102. Furthermore, the first ring gear 202 rotates circumferentially along the first ring gear 202 guide rail 201, thereby synchronously driving the bolt assembly 203 to achieve circumferential rotation, and the second ring gear 302 rotates circumferentially along the second ring gear 302 guide rail 301, thereby driving the nut assembly 303 to achieve circumferential rotation, so that the bolt and nut can be accurately positioned and aligned. Furthermore, when the bolt is correctly guided to the position, the claw or pin will automatically extend and clamp the bolt to ensure that it remains stable during the connection process. Once the bolt and nut are successfully connected, the drive member will act on the bolt locking member 203e to retract the claw or pin, thereby releasing the bolt and allowing it to move freely. Furthermore, after the bolt enters the nut, the tensioner in the tensioning unit 500 stretches the bolt to ensure that there is sufficient pre-tightening force, and the claw mechanism 401 fixes the flange 402 in the correct position.

[0068] In summary, the beneficial effects of a bolt tightening tool of the present invention are as follows: first, through the three-petal overall structure and the opening and closing function of the hydraulic cylinder, the tool can flexibly perform linear movement and circumferential rotation to adapt to different working environments and position requirements; secondly, the locking piece ensures the stability of the bolt during the connection process, and improves the accuracy and reliability of the connection; finally, the coordinated work of the tensioner and the claw mechanism 401 not only ensures the pre-tightening force of the bolt, but also ensures the correct fixation of the flange 402, thereby improving the efficiency and safety of the entire tightening process.

[0069] Example 3

[0070] Reference Figure 7-Figure 8 , which is a third embodiment of the present invention, provides a bolt fastening method, which includes:

[0071] S1. Use the Denavit-Hartenberg method (DH method) to define the coordinate system and calculate the position error and angle error between the bolt tip and the nut sleeve end;

[0072] It should be noted that the Denavit-Hartenberg method (DH method) is used to define the coordinate system, which uses α i ,θ i ,a i ,di Four elements are used to describe the relative position between two adjacent coordinate systems.

[0073] Reference Figure 8 , the initial coordinate system is O0-X0Y0Z0, the bolt unit coordinate system is O i -X i Y i Z i (i=1~5), the nut unit coordinate system is O i' -X i' Y i' Z i' (i=1~5).

[0074] Twist angle α i It's Z i-1 Axis and Z i Axis around X i The angle between the axes; the joint angle θ i Yes X i-1 Axis and X i Axis around Z i Angle between axes; length a i It's Z i-1 Axis and Z i Axis along X i Distance of the axis; offset d i is the origin of the i-1 coordinate system along Z i-1 Axis to X i The distance between the axes. According to the DH method, the general transformation formula is as follows:

[0075]

[0076] The transformation matrix of the bolt tip (far away from the bolt unit) relative to the initial coordinate system O0-X0Y0Z0 is:

[0077]

[0078] The transformation matrix of the bolt cap (in the bolt unit) relative to the initial coordinate system O0-X0Y0Z0 is:

[0079]

[0080] The transformation matrix of the nut sleeve end (away from the nut unit) relative to the initial coordinate system O0-X0Y0Z0 is:

[0081]

[0082] The transformation matrix of the bottom of the nut sleeve (in the nut unit) relative to the initial coordinate system O0-X0Y0Z0 is:

[0083]

[0084] From equations (2)-(5), we can see that the coordinates of the bolt and nut sleeve in the initial coordinate system O0-X0Y0Z0 can be expressed as α i ,θ i ,a i ,d i (i=1~5,1′~5′). In the initial coordinate system O0-X0Y0Z0, the coordinates of the bolt cap are (P x4 ,P y4 ,P z4 ); the bolt tip coordinate is (P x5 ,P y5 ,P z5 ), the bottom coordinate of the nut sleeve is (P x4' ,P y4' ,P z4' ); the coordinates of the nut and the end of the nut sleeve (P x5' ,P y5' ,P z5' ). Since the nut is located at the end of the nut sleeve and is coaxial with the nut sleeve, the position error between the bolt tip and the nut can be approximated as the position error between the bolt tip and the end of the nut sleeve, and the angular error between the bolt and the nut can be approximated as the angular error between the bolt and the nut sleeve.

[0085] In the O0-X0Y0Z0 coordinate system, the position error between the bolt tip and the nut sleeve end can be expressed as:

[0086] P j =P j (α i ,θ i ,a i ,d i )=|P j5 -P j5' |, (6)

[0087] Where: i = 1, 2, 3, 4, 5, 1', 2', 3', 4', 5 and j = x, y, z.

[0088] Taking the total differential on both sides of equation (6) and adding them together we get:

[0089]

[0090] Using Δα in formula (7) i ,Δθ i ,Δa i ,Δd i Instead of the differential dα i ,dθ i ,da i ,dd i, then the error between the tip of each axial bolt and the end of the nut sleeve can be rewritten as:

[0091]

[0092] In the initial coordinate system O0-X0Y0Z0, the total position error between the bolt tip and the nut sleeve end is:

[0093]

[0094] In actual operation, if there is an error in the Z-axis direction, it can be compensated by adjusting the position of the bolt unit and the nut unit on the Z-axis to ensure that the bolt and nut can be correctly aligned and connected to compensate for the error in the Z-axis direction. Therefore, the position error of the XOY plane is:

[0095]

[0096] The vector of the bolt in the O0-X0Y0Z0 coordinate system is:

[0097]

[0098] In the O0-X0Y0Z0 coordinate system, the vector of the nut sleeve is:

[0099]

[0100] Angle error between bolt and nut sleeve θ NB for:

[0101]

[0102] S2. Align by adjusting the positions and angles of the parts in the bolt unit and the nut unit;

[0103] S3. Use the tensioning unit to stretch the bolt.

[0104] In summary, the beneficial effect of a bolt fastening method of the present invention is that the position error and angle error between the bolt tip and the nut sleeve end are accurately calculated by using the coordinate system defined by the Denavit-Hartenberg method (DH method), thereby significantly improving the alignment accuracy of the bolt and the nut. This method not only improves the reliability and accuracy of the automated connection tool in a complex environment, but also reduces the connection failure caused by manufacturing errors by optimizing the manufacturing tolerance, thereby enhancing the fault tolerance of the tool.

[0105] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A bolt tightening tool, characterized in that: include, A skeleton unit (100), a bolt unit (200) that moves horizontally along the skeleton unit (100), a nut unit (300), an alignment unit (400), and a tensioning unit (500); The alignment unit (400) is disposed between the bolt unit (200) and the nut unit (300).

2. The bolt tightening tool according to claim 1, characterized in that: The skeleton unit (100) comprises a pipeline (101) and a linear guide rail (102) arranged parallel to the pipeline (101).

3. The bolt tightening tool according to claim 2, characterized in that: The bolt unit (200) comprises a first ring gear (202) guide rail (201) connected to the linear guide rail (102), a first ring gear (202) rotating circumferentially along the first ring gear (202) guide rail (201), and a bolt assembly (203) driven to rotate by the first ring gear (202).

4. The bolt tightening tool according to claim 3, characterized in that: The nut unit (300) comprises a second ring gear (302) guide rail (301) connected to the linear guide rail (102), a second ring gear (302) rotating circumferentially along the second ring gear (302) guide rail (301), and a nut assembly (303) driven to rotate by the second ring gear (302).

5. The bolt tightening tool according to claim 4, characterized in that: The overall structure of the bolt assembly (203) and the nut assembly (303) is a three-petal structure.

6. The bolt tightening tool according to claim 5, characterized in that: The bolt assembly (203) comprises a bolt first-flap fixing plate (203a) connected to the first ring gear (202), two first hydraulic cylinders (203b) connected at one end to the bolt first-flap fixing plate (203a), a bolt second-flap rotating plate (203c) and a bolt third-flap rotating plate (203d) connected to the output ends of the two first hydraulic cylinders (203b), and a bolt locking member (203e) arranged on the bolt first-flap fixing plate (203a), the bolt second-flap rotating plate (203c) and the bolt third-flap rotating plate (203d), wherein the bolt first-flap fixing plate (203a), the bolt second-flap rotating plate (203c) and the bolt third-flap rotating plate (203d) are closed to form an opening, and the cross-sectional size of the opening matches the cross-sectional size of the pipeline (101); One end of the second-petal rotating plate (203c) of the bolt and one end of the third-petal rotating plate (203d) of the bolt are respectively rotatably connected to the first-petal fixing plate (203a) of the bolt.

7. The bolt tightening tool according to claim 6, characterized in that: The nut assembly (303) comprises a nut first-lobe fixing plate (303a) connected to the second ring gear (302), two second hydraulic cylinders (303b) connected at one end to the nut first-lobe fixing plate (303a), a nut second-lobe rotating plate (303c) and a nut third-lobe rotating plate (303d) connected to the output ends of the two second hydraulic cylinders (303b), and a nut sleeve (303e) arranged on the nut first-lobe fixing plate (303a), the nut second-lobe rotating plate (303c) and the nut third-lobe rotating plate (303d), wherein the nut first-lobe fixing plate (303a), the nut second-lobe rotating plate (303c) and the nut third-lobe rotating plate (303d) are closed to form an opening, and the cross-sectional size of the opening matches the cross-sectional size of the pipeline (101); One end of the nut second-lobe rotating plate (303c) and one end of the nut third-lobe rotating plate (303d) are respectively rotatably connected to the nut first-lobe fixing plate (303a).

8. The bolt tightening tool according to claim 7, characterized in that: The alignment unit (400) comprises a claw mechanism (401) that moves horizontally along the linear guide rail (102), and a flange (402) that is sleeved on the pipe (101); The claw mechanism (401) is used to fix the flange (402).

9. The bolt tightening tool according to claim 8, characterized in that: It also includes a control panel (600) for controlling the first hydraulic cylinder (203b) and the second hydraulic cylinder (303b).

10. A bolt tightening method, applied to the bolt tightening tool according to any one of claims 1 to 8, characterized in that: The Denavit-Hartenberg method (DH method) is used to define the coordinate system and calculate the position error and angle error between the bolt tip and the nut sleeve end; Aligning by adjusting the positions and angles of parts in the bolt unit (200) and the nut unit (300); The bolt is stretched using the tensioning unit (500).

Images