Anchor cable with high pre-tightening force

Abstract

The utility model discloses a high-pretightening-force anchor cable, and belongs to the technical field of anchoring equipment. The structure comprises an anchor cable main body (1), an anchorage device (3) and a top plate (8), and further comprises a pre-tightening piece (4), external threads are arranged on the outer side of the anchorage device (3), the anchor cable main body (1) is sleeved with the pre-tightening piece (4), the pre-tightening piece (4) is located between the top plate (8) and the anchorage device (3), and internal threads are arranged on the pre-tightening piece (4), so that the anchorage device (3) is in threaded connection with the pre-tightening piece (4). According to the structure, the clamping piece (2) is extruded by the anchorage device (3) by screwing the pre-tightening piece (4), and an external force is applied to the anchor cable main body (1) again to supplement the loss of the pre-tightening force, so that the purpose of high pre-tightening force of the anchor cable is achieved. The problems that a large amount of anchor cable prestress is lost due to elastic extension of an existing anchor cable in the tensioning process and the compression amount of a lock in the anchor cable locking process, a supporting structure is displaced, and an anchoring structure is unstable are solved.

Description

Technical Field

[0001] The utility model discloses a high pre-tightening force anchor cable, belonging to the technical field of anchoring equipment. Background Art

[0002] At present, the anchor cables used in coal mines generally adopt the self-locking anchors of the OVM series. The force-adding device generally adopts a through-hole jack, and a high-pressure oil pump is used to apply tension to the anchor cables. The reaction device is composed of a tool anchor and its clips. However, due to the elastic elongation of the anchor cable during tensioning and the compression of the lock when the anchor cable is locked, a large amount of prestress of the anchor cable is lost, which will result in a large displacement of the supporting structure, and the prestressed anchor cable is not really played. In serious cases, the tunnel will be in a dangerous state, and even a roof fall accident will occur, threatening personal safety. Utility Model Content

[0003] The technical problem to be solved by the utility model is that the elastic elongation of the existing anchor cable when being tensioned and the compression of the lock when the anchor cable is locked cause a large loss of prestress of the anchor cable, resulting in displacement of the supporting structure and instability of the anchoring structure.

[0004] The technical solution adopted by the utility model to solve its technical problems is: a high preload anchor cable, including an anchor cable body, an anchor and a top plate, and also a preload piece, the outer side of the anchor is provided with an external thread, the preload piece is sleeved on the anchor cable body and is located between the top plate and the anchor, and the preload piece is provided with an internal thread, so that the anchor and the preload piece are threadedly connected.

[0005] Wherein, in the above structure, at least one set of planes is symmetrically arranged on the outer side wall of the preload member.

[0006] Furthermore, the pre-tightening member in the above structure is a hexagonal nut.

[0007] Wherein, the above structure also includes a rolling friction gasket, which is sleeved on the anchor cable body and located between the top plate and the preload member.

[0008] Wherein, the above structure also includes a tray, which is sleeved on the anchor cable body and located between the preload member and the top plate, and the concave side of the tray is in contact with the top plate.

[0009] Furthermore, the above structure also includes a self-aligning ball pad, which is penetrated on the anchor cable body, and the arc surface of the self-aligning ball pad is in contact with the side of the tray away from the top plate, and the other side is in contact with the preloaded part.

[0010] Furthermore, in the above structure, the diameter of the through hole in the middle of the rolling friction gasket is larger than the outer diameter of the threaded section of the anchor.

[0011] Furthermore, in the above structure, the diameter of the through hole in the middle of the rolling friction gasket is 1.1 to 1.5 times the outer diameter of the threaded section of the anchor.

[0012] The beneficial effects of the utility model are as follows: the structure is provided with threads on the outer peripheral surface of the anchor cable, and is equipped with preload parts and rolling friction pads. When the hexagonal anchor nut is twisted, the friction between it and the self-aligning ball pad is reduced by the rolling friction pad, which greatly reduces the difficulty of twisting the preload part. In addition, the structure is tensioned by the conventional process by pulling out the anchor cable in the test. When the anchor cable generates a certain preload force, the hexagonal anchor nut is twisted toward the tensioning instrument with a torque wrench. At this time, the anchor squeezes the clip, and an external force is applied to the anchor cable again to supplement the loss of preload force, thereby achieving the purpose of high preload force of the anchor cable. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the initial structure of the utility model;

[0014] Figure 2 It is a schematic diagram of the structure of the utility model after the pre-tightening member is twisted.

[0015] The markings in the figure are: 1. Anchor cable body; 2. Clip; 3. Anchor; 4. Preload; 5. Rolling friction pad; 6. Self-aligning ball pad; 7. Tray; 8. Top plate. DETAILED DESCRIPTION

[0016] The utility model is further described below in conjunction with the accompanying drawings.

[0017] like Figure 1 and Figure 2 As shown, the high preload anchor cable of the utility model includes an anchor cable body 1, an anchor 3 and a top plate 8, and also includes a preload piece 4. The anchor 3 is provided with an external thread on the outside, and the preload piece 4 is sleeved on the anchor cable body 1 and is located between the top plate 8 and the anchor 3. The preload piece 4 is provided with an internal thread, so that the anchor 3 is threadedly connected to the preload piece 4. Those skilled in the art can understand that, in the present structure, an external thread is arranged on the outer side of the anchor 3, and an adaptable internal thread is arranged on the inner wall of the preload member 4, so that the preload member 4 is threadedly connected to the anchor 3. This structural setting is used to perform a pulling test to tension the anchor cable according to a conventional process. When a certain preload force is generated in the anchor cable body, the preload member 4 is twisted toward the tensioner with a torque wrench. Since the existing anchor cable body 1 is connected to the anchor 3 through the clip 2, the anchor 3 squeezes the clip 2 at this time, and an external force is applied to the anchor cable body 1 again to supplement the loss of the preload force, thereby achieving the purpose of high preload force of the anchor cable, and the preload force can reach 2 to 3 times that of the existing anchor cable, which is about 40 to 60 tons.

[0018] Preferably, in the above structure, at least one set of planes is symmetrically arranged on the outer wall of the preload member 4. Those skilled in the art will appreciate that, in order to facilitate the twisting of the preload member 4, the present structure preferably has at least one set of planes symmetrically arranged on the outer wall of the preload member 4, and the symmetrical planes are arranged in parallel, so that the torque wrench and the preload member 4 are easily fixed by a set of planes.

[0019] Preferably, the pre-tightening member 4 in the above structure is a hexagonal nut. Those skilled in the art will appreciate that, in this structure, the pre-tightening member 4 is preferably a hexagonal nut to reduce costs and facilitate twisting.

[0020] Preferably, the above structure further includes a rolling friction pad 5, which is sleeved on the anchor cable body 1 and located between the top plate 8 and the preload member 4. Those skilled in the art can understand that, in order to reduce the torsional friction between the preload member 4 and the top plate 8, the device preferably has the rolling friction pad 5 sleeved on the anchor cable body 1 and located between the top plate 8 and the preload member 4, so that the preload member 4 is actually in contact with the top plate 8 through the rolling friction pad 5, thereby reducing the friction coefficient and facilitating the torsional preload of the preload member 4.

[0021] Preferably, the above structure also includes a tray 7, which is sleeved on the anchor body 1 and located between the preload 4 and the top plate 8, and the concave side of the tray 7 is in contact with the top plate 8. It can be understood by those skilled in the art that in order to increase the force-bearing area of ​​the preload 4 and the top plate 8 and ensure the stability of the anchoring structure. The device is preferably provided with a tray 7, specifically, the tray 7 is sleeved on the anchor body 1 and located between the preload 4 and the top plate 8, and the concave side of the tray 7 is in contact with the top plate 8, so that the threaded preload force of the preload 4 acts directly.

[0022] Preferably, the above structure also includes a self-aligning ball pad 6, which is inserted into the anchor cable body 1, and the arc surface of the self-aligning ball pad 6 is in contact and connected with the side of the tray 7 away from the top plate 8, and the other side is in contact and connected with the preload member 4. It can be understood by those skilled in the art that in order to ensure that the axial deviation of the anchor cable body meets the requirements, the self-aligning ball pad 6 of the present structure is preferably inserted into the anchor cable body 1, and the arc surface of the self-aligning ball pad 6 is kept in contact and connected with the side of the tray 7 away from the top plate 8, and the other side is in contact and connected with the preload member 4.

[0023] Preferably, the diameter of the through hole in the middle of the rolling friction pad 5 in the above structure is larger than the outer diameter of the threaded section of the anchor 3. Those skilled in the art can understand that in this structure, the diameter of the through hole in the middle of the rolling friction pad 5 is preferably larger than the outer diameter of the threaded section of the anchor 3, which can actually allow the inner end of the anchor 3 to penetrate into the rolling friction pad 5, so that the rolling friction pad 5 and the preload member 4 are coaxially arranged.

[0024] Preferably, the diameter of the through hole in the middle of the rolling friction pad 5 in the above structure is 1.1 to 1.5 times the outer diameter of the threaded section of the anchor 3. Those skilled in the art can understand that, in this structure, it is further preferred that the diameter of the through hole in the middle of the rolling friction pad 5 is 1.1 to 1.5 times the outer diameter of the threaded section of the anchor 3.

Claims

1. A high preload anchor cable, comprising an anchor cable body (1), an anchor (3) and a top plate (8), characterized in that: It also includes a pre-tightening member (4), the outer side of the anchor (3) is provided with an external thread, the pre-tightening member (4) is sleeved on the anchor cable body (1), and is located between the top plate (8) and the anchor (3), and the pre-tightening member (4) is provided with an internal thread, so that the anchor (3) and the pre-tightening member (4) are threadedly connected.

2. The high preload anchor cable according to claim 1, characterized in that: At least one group of planes is symmetrically arranged on the outer side wall of the pre-tightening member (4).

3. The high preload anchor cable according to claim 2, characterized in that: The pre-tightening member (4) is a hexagonal nut.

4. The high preload anchor cable according to claim 1, characterized in that: It also comprises a rolling friction pad (5), which is sleeved on the anchor cable body (1) and located between the top plate (8) and the pre-tightening member (4).

5. The high preload anchor cable according to claim 1, characterized in that: It also comprises a tray (7), which is sleeved on the anchor cable body (1) and located between the pre-tightening member (4) and the top plate (8), and the concave side of the tray (7) is in contact with the top plate (8).

6. The high preload anchor cable according to claim 5, characterized in that: It also includes a self-aligning ball pad (6), which is inserted into the anchor cable body (1), and the arc surface of the self-aligning ball pad (6) is in contact with the side of the tray (7) away from the top plate (8), and the other side is in contact with the preload member (4).

7. The high preload anchor cable according to claim 4, characterized in that: The diameter of the through hole in the middle of the rolling friction pad (5) is larger than the outer diameter of the threaded section of the anchor (3).

8. The high preload anchor cable according to claim 7, characterized in that: The diameter of the through hole in the middle of the rolling friction pad (5) is 1.1 to 1.5 times the outer diameter of the threaded section of the anchor (3).

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