Tensioning type anchor rod pre-tightening device

Abstract

The utility model discloses a tensioning type anchor rod pre-tightening device which comprises a tensioning support used for abutting against an anchor rod base plate, an outer sleeve used for locking an anchor rod, an inner sleeve used for tensioning the anchor rod, a gearbox, a driving mechanism and a rotating connector used for being connected with a grouting pipeline. The tensioning support is installed at one end of the gearbox, the outer sleeve and the inner sleeve are rotationally connected with the gearbox, and the rotary connector communicates with the end, away from the tensioning support, of the inner sleeve. The driving mechanism comprises a first motor used for driving the outer sleeve to rotate, a second motor used for driving the inner sleeve to rotate, a tensioning oil cylinder used for driving the inner sleeve to tension the anchor rod in the axial direction of the inner sleeve, a first reset spring arranged on the outer sleeve in a sleeving mode, and a second reset spring arranged on the inner sleeve in a sleeving mode. The anchor rod pre-tightening device can provide high pre-tightening force and guarantee the pre-tightening effect, integrates anchor rod pushing, anchor rod tensioning, anchor rod locking and grouting, and has the advantages of being high in automation degree and high in working efficiency.

Description

Technical Field

[0001] The utility model relates to the technical field of prestressed anchor rod tensioning equipment, in particular to a tensioning anchor rod pre-tightening device. Background Art

[0002] In a large number of tunnel construction, the application of anchor rods can play a role in strengthening rock and soil through suspension, extrusion, and the formation of composite beams (arches). Unlike traditional support structures that passively resist external forces, anchor support can change the stress state of the surrounding rock mass and reduce the movement of the surrounding rock toward the open surface, thereby playing a braking and protective role to a certain extent. It also shows that its support effect is significant and the support cost is economical.

[0003] Among them, prestressed anchor rods apply prestress so that the surrounding rock is tightly locked together under the bidirectional action of the inner anchor section and the return member, and at the same time generate an outward support force on the surrounding rock, limiting the sinking and convergence deformation of the surrounding rock, so as to maintain the stability of the rock and soil. Compared with ordinary anchor rods, prestressed anchor rods can actively apply pressure to the surrounding rock, will not overly rely on the strength of the surrounding rock itself, and can effectively control the deformation of the surrounding rock. Compared with steel arch support, prestressed anchor rods have the advantages of being light, economical, and effective, and can make full use of the tensile strength of steel. Generally speaking, applying prestress (pretightening force) is the main means for anchor rods to play an active support role on the surrounding rock. The greater the prestress (pretightening force), the more conducive it is to play the active support role of the anchor rod.

[0004] With the increase in the intensity of mineral resource mining and the large-scale construction of underground projects, the support conditions of underground projects such as lanes, tunnels, and tunnels have become increasingly harsh, which puts forward higher requirements for the support effect of prestressed anchor rods. Existing prestressed anchor rod tensioning devices, such as the Chinese patent CN218322734U, use electric telescopic rods to drive the tensioning of anchor rods, which can save a certain amount of manpower. However, the device can only tension the anchor rods that are already on the surrounding rock, and cannot push the anchor rods in; secondly, the device does not have a prestressed anchor rod locking process, and the prestress is poorly maintained; thirdly, after the anchor rod tensioning is completed, the prestressed anchor rod tensioning device needs to be removed and the grouting pipeline needs to be connected separately, which has low work efficiency. Utility Model Content

[0005] The utility model provides a tensioning anchor rod pre-tightening device to solve the technical problems of the existing prestressed anchor rod tensioning device having single function, low working efficiency and poor prestress maintenance.

[0006] According to one aspect of the utility model, a tensioning anchor pre-tensioning device is provided, comprising a tensioning support for abutting an anchor pad, an outer sleeve for locking the anchor, an inner sleeve for tensioning the anchor, a gear box, a driving mechanism and a rotary joint for connecting a grouting pipe, the tensioning support, the outer sleeve and the inner sleeve are coaxially arranged, the tensioning support is installed on one end of the gear box, the outer sleeve and the inner sleeve are respectively rotatably connected to the gear box, the rotary joint is connected to an end of the inner sleeve away from the tensioning support, the driving mechanism comprises a first motor for driving the outer sleeve to rotate, a second motor for driving the inner sleeve to rotate, a tensioning cylinder for driving the inner sleeve to tension the anchor along its axial direction, a first return spring sleeved on the outer sleeve and a second return spring sleeved on the inner sleeve.

[0007] Furthermore, the gear box is provided with a first connecting sleeve for driving the outer sleeve to rotate, a first large gear arranged on the first connecting sleeve and driven by the first motor, a first bearing for supporting the first connecting sleeve, a second connecting sleeve for driving the inner sleeve to rotate, a second large gear arranged on the second connecting sleeve and driven by the second motor, and a second bearing for supporting the second connecting sleeve.

[0008] Furthermore, the first return spring is arranged between the outer sleeve and the first connecting sleeve, and the second return spring is arranged between the inner sleeve and the second connecting sleeve.

[0009] Furthermore, a card interface is arranged at one end of the outer sleeve away from the gear box, and a locking nut threadedly connected to the anchor rod is arranged in the card interface.

[0010] Furthermore, the outer periphery of the card interface is provided with a bell mouth for guiding the insertion of the locking nut.

[0011] Furthermore, a threaded opening for screwing an anchor rod is arranged at the first end of the inner sleeve, and an end nut adapted to the tensioning cylinder is arranged at the second end.

[0012] Furthermore, the tension support includes an abutment ring for abutting against an anchor plate, a connecting ring for connecting the gear box, and a support rod for connecting the abutment ring and the connecting ring.

[0013] Furthermore, the plurality of support rods are evenly arranged along the circumferential direction of the abutment ring.

[0014] Furthermore, a support ring is arranged between the abutment ring and the connection ring, and the support ring is sleeved on the support rod.

[0015] Furthermore, a plurality of the support rings are arranged at intervals.

[0016] The utility model has the following beneficial effects:

[0017] The tensioning anchor pre-tightening device of the utility model has an end close to the anchor as the front end and an end away from the anchor as the rear end. The tensioning support abuts against the anchor pad, and the anchor pad is supported and fixed on the inner wall of the tunnel to ensure that the tensioning cylinder tensions the anchor through the inner sleeve to apply pre-tensioning stress; the inner sleeve is connected to the tail end of the anchor by a thread, and the anchor is pushed forward by rotation, and the inner sleeve is supported by the tensioning cylinder to achieve tensioning of the anchor by the inner sleeve; the second motor drives the inner sleeve to rotate to achieve connection, advancement and separation of the anchor from the anchor; the first return spring can apply a forward elastic force to the outer sleeve, and the second return spring can apply a forward elastic force to the inner sleeve, to ensure smooth advancement of the anchor and reset the inner sleeve and the outer sleeve after the tensioning anchor is tensioned; after the anchor is pushed, the tensioning cylinder is pulled upward by the tensioning cylinder The inner sleeve is supported to realize the tensioning of the anchor rod by the inner sleeve; after the anchor rod reaches the preset preload force requirement, the first motor drives the outer sleeve to rotate, locks and fixes the anchor rod; the rotary joint connects the inner sleeve with the grouting pipe, and when the inner sleeve rotates, the grouting pipe does not rotate accordingly; after the anchor rod is tensioned and locked, grouting can be carried out through the grouting pipe; it drives the outer sleeve and the inner sleeve to rotate respectively through the driving mechanism, and drives the inner sleeve to tension the anchor rod through the tensioning cylinder. After the tensioning is completed, the inner sleeve remains stationary, and the anchor rod is locked by the outer sleeve, which can provide high preload force and ensure the preload effect. It integrates the advancement of anchor rods, tensioning anchor rods, locking anchor rods and grouting, can be carried on a trolley for construction, can well meet the current requirements of prestressed anchor support in tunnels, and has the advantages of high degree of automation and high work efficiency.

[0018] In addition to the above-described purposes, features and advantages, the present invention has other purposes, features and advantages. The present invention will be further described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The drawings constituting a part of this application are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention. In the drawings:

[0020] Figure 1 It is a structural schematic diagram of a tensioned anchor rod pre-tightening device of a preferred embodiment of the utility model;

[0021] Figure 2 It is a structural schematic diagram of a tension support of a preferred embodiment of the utility model;

[0022] Figure 3 It is a structural schematic diagram of an outer sleeve of a preferred embodiment of the utility model;

[0023] Figure 4This is a structural schematic diagram of the bell mouth of a preferred embodiment of the utility model;

[0024] Figure 5 It is a structural schematic diagram of a locking nut according to a preferred embodiment of the utility model.

[0025] Legend:

[0026] 100. Anchor rod; 101. Anchor rod pad; 1. Tensioning support; 11. Abutment ring; 12. Connecting ring; 13. Support rod; 14. Support ring; 2. Outer sleeve; 21. Card interface; 22. Locking nut; 23. Bell mouth; 3. Inner sleeve; 31. Threaded mouth; 32. End nut; 4. Gear box; 41. First connecting sleeve; 42. First large gear; 43. First bearing; 44. Second connecting sleeve; 45. Second large gear; 46. Second bearing; 5. Driving mechanism; 51. First motor; 52. Second motor; 53. Tensioning cylinder; 54. First return spring; 55. Second return spring; 6. Rotary joint. DETAILED DESCRIPTION

[0027] The embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. However, the present invention can be implemented in a variety of different ways as defined and covered below.

[0028] Please also read Figures 1 to 5 The tension anchor pre-tightening device of this embodiment includes a tensioning support 1 for abutting against an anchor pad 101, an outer sleeve 2 for locking the anchor 100, an inner sleeve 3 for tensioning the anchor 100, a gear box 4, a driving mechanism 5 and a rotary joint 6 for connecting a grouting pipe. The tensioning support 1, the outer sleeve 2 and the inner sleeve 3 are coaxially arranged, the tensioning support 1 is installed on one end of the gear box 4, the outer sleeve 2 and the inner sleeve 3 are respectively rotatably connected to the gear box 4, the rotary joint 6 is connected to the end of the inner sleeve 3 away from the tensioning support 1, the driving mechanism 5 includes a first motor 51 for driving the outer sleeve 2 to rotate, a second motor 52 for driving the inner sleeve 3 to rotate, a tensioning cylinder 53 for driving the inner sleeve 3 to tension the anchor 100 along its axial direction, a first return spring 54 sleeved on the outer sleeve 2 and a second return spring 55 sleeved on the inner sleeve 3.

[0029] The tensioning anchor pre-tightening device of this embodiment has the end close to the anchor 100 as the front end and the end away from the anchor 100 as the rear end. The tensioning support 1 abuts against the anchor pad 101, and the anchor pad 101 is supported and fixed on the inner wall of the tunnel, ensuring that the tensioning cylinder 53 tensions the anchor 100 through the inner sleeve 3 to apply pre-tensioning stress; the inner sleeve 3 is connected to the rear end of the anchor 100 by threading, and the anchor 100 is pushed forward by rotation, and the inner sleeve is supported by the tensioning cylinder 53. 3, realize the tensioning of the anchor rod 100 by the inner sleeve 3; the second motor 52 drives the inner sleeve 3 to rotate, so as to realize the connection, advancement and separation of the anchor rod 100; the first return spring 54 can apply a forward elastic force to the outer sleeve 2, and the second return spring 55 can apply a forward elastic force to the inner sleeve 3, so as to ensure the smooth advancement of the anchor rod 100 and reset the inner sleeve 3 and the outer sleeve 2 after the tensioning action of the anchor rod 100; the tensioning cylinder 53 is pushed when the anchor rod 100 is advanced. After the action is completed, the tensioning cylinder 53 is used to support the inner sleeve 3 to achieve the tensioning of the anchor rod 100 by the inner sleeve 3; after the anchor rod 100 reaches the preset preload force requirement, the first motor 51 drives the outer sleeve 2 to rotate, locks and fixes the anchor rod 100; the rotary joint 6 connects the inner sleeve 3 with the grouting pipe, and when the inner sleeve 3 rotates, the grouting pipe does not rotate accordingly; after the anchor rod 100 is tensioned and locked, grouting can be carried out through the grouting pipe; it drives the outer sleeve 2 and the inner sleeve 3 to rotate respectively through the driving mechanism 5, and drives the inner sleeve 3 to tension the anchor rod 100 through the tensioning cylinder 53. After the tensioning is completed, the inner sleeve 3 remains stationary, and the anchor rod 100 is locked by the outer sleeve 2, which can provide high preload force and ensure the preload effect. It integrates the propulsion anchor rod, tensioning anchor rod, locking anchor rod and grouting, can be carried on a trolley for operation and construction, can well meet the current requirements of prestressed anchor support in tunnels, and has the advantages of high degree of automation and high work efficiency.

[0030] In this embodiment, the gear box 4 is provided with a first connecting sleeve 41 for driving the outer sleeve 2 to rotate, a first large gear 42 arranged on the first connecting sleeve 41 and driven by a first motor 51, a first bearing 43 for supporting the first connecting sleeve 41, a second connecting sleeve 44 for driving the inner sleeve 3 to rotate, a second large gear 45 arranged on the second connecting sleeve 44 and driven by a second motor 52, and a second bearing 46 for supporting the second connecting sleeve 44; the gear box 4 is provided with an outer sleeve driving cavity and an inner sleeve driving cavity, and both ends of the first connecting sleeve 41 in the outer sleeve driving cavity are rotatably connected to the gear box 4 through the first bearing 43, and the first connecting sleeve 41 is connected to the outer sleeve 2 through a spline, so that the first connecting sleeve 41 is both It can drive the outer sleeve 2 to rotate and provide space for the axial movement of the outer sleeve 2. The output shaft of the first motor 51 is meshed with the first large gear 42 through a small gear, thereby driving the outer sleeve 2 to rotate; the two ends of the second connecting sleeve 44 in the inner sleeve driving cavity are rotatably connected to the gear box 4 through the second bearing 46, and the second connecting sleeve 44 and the inner sleeve 3 are connected by a spline, so that the second connecting sleeve 44 can not only drive the inner sleeve 3 to rotate, but also provide space for the axial movement of the inner sleeve 3. The output shaft of the second motor 52 is meshed with the second large gear 45 through a small gear, thereby driving the inner sleeve 3 to rotate; the gear box 4 has a reasonable structure and can provide a closed transmission environment to prevent external dust from entering, thereby ensuring the normal operation of the tensioned anchor pretensioning device.

[0031] In this embodiment, the first return spring 54 is arranged between the outer sleeve 2 and the first connecting sleeve 41, and the second return spring 55 is arranged between the inner sleeve 3 and the second connecting sleeve 44. On the one hand, it can provide a closed working environment for the first return spring 54 and the second return spring 55; on the other hand, it can radially limit the first return spring 54 and the second return spring 55 to avoid spring deflection and deformation, thereby improving the service life of the spring.

[0032] In this embodiment, a card interface 21 is arranged at one end of the outer sleeve 2 away from the gear box 4, and a locking nut 22 connected to the anchor rod by threading is arranged inside the card interface 21. The first return spring 54 applies a forward thrust to the outer sleeve 2, so that the card interface 21 abuts against the locking nut 22, and the position of the locking nut 22 is adjusted to be inserted into the card interface 21. The card interface 21 fits the outer contour surface of the locking nut 22, and the first motor 51 drives the outer sleeve 2 to rotate counterclockwise, so that the locking nut 22 cooperates with the anchor rod pad 101 to lock the anchor rod 10. Optionally, the card interface 21 is a hexagon, and correspondingly, the end of the locking nut 22 inserted into the card interface 21 is also a hexagon, which has a simple structure and is easy to process; it can be understood that the card interface 21 can also be other polygonal structures or circular hole structures with keyways, and the shape of the insertion end of the locking nut 22 is adjusted accordingly to prevent the card interface 21 and the locking nut 22 from rotating relative to each other.

[0033] In this embodiment, a bell mouth 23 for guiding the locking nut 22 to be inserted is arranged on the periphery of the card interface 21 to assist the locking nut 22 in being inserted into the card interface 21 , thereby reducing the difficulty of assembly and improving the efficiency of assembly.

[0034] In this embodiment, the first end of the inner sleeve 3 is provided with a threaded opening 31 for screwing the anchor rod, and the second end is provided with an end nut 32 adapted to the tensioning cylinder 53. When the anchor rod 100 needs to be connected, the second motor 52 drives the inner sleeve 3 to rotate counterclockwise, and the threaded opening 31 of the inner sleeve 3 is screwed with the anchor rod 100; the tensioning cylinder 53 is pushed out, abuts against the end nut 32 of the inner sleeve 3, and drives the inner sleeve 3 to move backward, so that the inner sleeve 3 is tensioned on the anchor rod 100, and the tensioning cylinder 53 is pushed out, abuts against the end nut 32 of the inner sleeve 3, and drives the inner sleeve 3 to move backward, so that the inner sleeve 3 is tensioned on the anchor rod 100, and the tensioning cylinder 53 is pushed out. Preset preload force requirement; when the tensioning anchor preload device is withdrawn, the second motor 52 drives the inner sleeve 3 to rotate clockwise, and the inner sleeve 3 moves backward, continuing to compress the second reset spring 55, and the threaded mouth 31 of the inner sleeve 3 is disengaged from the anchor 100, and the end nut 32 is disengaged from the tensioning cylinder 53, and the tensioning anchor preload device retreats as a whole, and the tensioning cylinder 53 is retracted. The anchor push preload is completed, and the inner sleeve 3 is reset under the action of the second reset spring 55, and all return to the initial state.

[0035] In this embodiment, the tensioning support 1 includes an abutment ring 11 for abutting the anchor pad 101, a connecting ring 12 for connecting the gear box 4, and a support rod 13 for connecting the abutment ring 11 and the connecting ring 12. The tensioning support 1 is installed on the gear box 4 through the connecting ring 12. It has a simple structure, a firm connection, and can provide stable support.

[0036] In this embodiment, a plurality of support rods 13 are evenly arranged along the circumferential direction of the abutment ring 11 to ensure uniform force and avoid deformation of the support rods 13 .

[0037] In this embodiment, a support ring 14 is arranged between the abutment ring 11 and the connection ring 12 . The support ring 14 is sleeved on the support rod 13 , which can prevent the support rod 13 from bending and deforming, and increase the strength of the tension support 1 .

[0038] In this embodiment, two support rings 14 are arranged at intervals, which can further enhance the strength of the tension support 1. It is understandable that the number of support rings 14 can be increased according to usage requirements, and the number of support rings 14 can also be three, four or more.

[0039] The working process of the tension anchor pre-tightening device of the utility model is as follows:

[0040] Before working, the locking nut 22 is screwed onto the anchor rod 100;

[0041] During the connection process, the rod body of the anchor rod 100 contacts the front end face of the inner sleeve 3, the distance between the rear end face of the locking nut 22 and the rear end face of the anchor rod 100 is 35 mm, and the distance between the front end face of the outer sleeve 2 and the first thread of the front end of the inner sleeve 3 is 43 mm; therefore, when the rod body of the anchor rod 100 contacts the front end face of the inner sleeve 3, if the card interface 21 of the outer sleeve 2 is aligned with the hexagonal profile of the locking nut 22, the locking nut 22 can be smoothly inserted into the card interface 21, and the first reset spring 54 is not compressed; if the card interface 21 is not aligned with the hexagonal profile of the locking nut 22, the first reset spring 54 is compressed, and the locking nut 22 or the outer sleeve 2 needs to be rotated so that the locking nut 22 is inserted into the card interface 21;

[0042] During the advancement process, the second motor 52 drives the inner sleeve 3 to rotate counterclockwise, so that the threaded opening 31 of the inner sleeve 3 is screwed with the rod body of the anchor rod 100. After the inner sleeve 3 is connected with the rod body of the anchor rod 100, it continues to rotate counterclockwise. At this time, the tension anchor pre-tightening device is pushed forward as a whole to realize the advancement of the anchor rod 100. After the anchor rod 100 is pushed into place, the tension support 1 maintains a certain force to support the anchor rod pad 101 to make it close to the rock surface. The outer sleeve 2 does not rotate during the entire advancement process;

[0043] During the tensioning process, when the tensioning support 1 supports the anchor plate 101, the tensioning cylinder 53 is pushed out, and the inner sleeve 3 is tensioned on the anchor 100 by supporting the end nut 32 at the rear end of the inner sleeve 3 until the preset preload force requirement is reached; at this time, the anchor 100 rod body and the locking nut 22 move backward together, the first return spring 54 is compressed, and the compression length of the second return spring 55 is the tensioning length of the anchor 100;

[0044] During the locking process, the inner sleeve 3 is fixed, and the first motor 51 drives the outer sleeve 2 to rotate counterclockwise, the inner contour surface of the card interface 21 cooperates with the outer contour surface of the locking nut 22, and drives the locking nut 22 to rotate under the push of the first return spring 54, until the locking nut 22 abuts against the anchor plate 101, thereby locking the anchor 100, and the grouting pipe injects grout into the anchor 100 through the rotary joint 6 and the inner sleeve 3;

[0045] During the exit process, after the grouting is completed, the second motor 52 drives the inner sleeve 3 to rotate clockwise, and the inner sleeve 3 is disengaged from the anchor rod 100. At this time, the inner sleeve 3 moves backward and continues to compress the second return spring 55, and the end nut 32 at the tail end of the inner sleeve 3 is disengaged from the tensioning cylinder 53; the tensioning anchor rod pre-tightening device retreats as a whole, the tensioning cylinder 53 is retracted, the outer sleeve 2 is reset under the action of the first return spring 54, and the inner sleeve 3 is reset under the action of the second return spring 55, returning to the initial state.

[0046] The above description is only the preferred embodiment of the utility model, and is not intended to limit the utility model. For those skilled in the art, the utility model can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A tension anchor pre-tightening device, characterized in that: The invention comprises a tensioning support (1) for contacting an anchor rod pad, an outer sleeve (2) for locking the anchor rod, an inner sleeve (3) for tensioning the anchor rod, a gear box (4), a driving mechanism (5) and a rotary joint (6) for connecting a grouting pipe. The tension support (1), the outer sleeve (2) and the inner sleeve (3) are coaxially arranged, the tension support (1) is mounted on one end of the gear box (4), the outer sleeve (2) and the inner sleeve (3) are rotatably connected to the gear box (4) respectively, and the rotary joint (6) is connected to one end of the inner sleeve (3) away from the tension support (1). The driving mechanism (5) comprises a first motor (51) for driving the outer sleeve (2) to rotate, a second motor (52) for driving the inner sleeve (3) to rotate, a tensioning cylinder (53) for driving the inner sleeve (3) to tension the anchor rod along its axial direction, a first return spring (54) sleeved on the outer sleeve (2), and a second return spring (55) sleeved on the inner sleeve (3).

2. The tension anchor pre-tightening device according to claim 1, characterized in that: The gear box (4) is provided with a first connecting sleeve (41) for driving the outer sleeve (2) to rotate, a first large gear (42) arranged on the first connecting sleeve (41) and driven by the first motor (51), a first bearing (43) for supporting the first connecting sleeve (41), a second connecting sleeve (44) for driving the inner sleeve (3) to rotate, a second large gear (45) arranged on the second connecting sleeve (44) and driven by the second motor (52), and a second bearing (46) for supporting the second connecting sleeve (44).

3. The tension anchor pre-tightening device according to claim 2, characterized in that: The first return spring (54) is arranged between the outer sleeve (2) and the first connecting sleeve (41), and the second return spring (55) is arranged between the inner sleeve (3) and the second connecting sleeve (44).

4. The tension anchor pre-tightening device according to claim 1, characterized in that: A clamping interface (21) is arranged at one end of the outer sleeve (2) away from the gear box (4), and a locking nut (22) threadedly connected to the anchor rod is arranged inside the clamping interface (21).

5. The tension anchor pre-tightening device according to claim 4, characterized in that: The outer periphery of the card interface (21) is provided with a bell mouth (23) for guiding the insertion of the locking nut (22).

6. The tension anchor pre-tightening device according to claim 1, characterized in that: The first end of the inner sleeve (3) is provided with a threaded opening (31) for threaded connection with an anchor rod, and the second end is provided with an end nut (32) adapted to the tensioning cylinder (53).

7. The tension anchor pre-tightening device according to claim 1, characterized in that: The tension support (1) comprises an abutment ring (11) for abutting against an anchor plate, a connection ring (12) for connecting the gear box (4), and a support rod (13) for connecting the abutment ring (11) and the connection ring (12).

8. The tension anchor pre-tightening device according to claim 7, characterized in that: The plurality of support rods (13) are evenly arranged along the circumferential direction of the abutment ring (11).

9. The tension anchor pre-tightening device according to claim 8, characterized in that: A support ring (14) is arranged between the abutment ring (11) and the connection ring (12), and the support ring (14) is sleeved on the support rod (13).

10. The tension anchor pre-tightening device according to claim 9, characterized in that: A plurality of the support rings (14) are arranged at intervals.

Images