A mine spherical step anchor

Abstract

The present specification discloses a kind of mining spherical step anchor device, which is the equipment for anchoring prestressed anchor cable, suitable for Ф21.8mm 1860MPa grade roadway support steel strand, compact structure, anchoring is reliable.The anchor device is mainly composed of anchor ring and three pieces of bevel type working clamping piece, the anchor ring has spherical end face, cooperates with tray with spherical groove, outer side is equipped with arc stepped skirt, the inner side of working clamping piece has inner tooth, and anchoring is realized by the positive pressure extrusion of anchor ring inner taper hole and clamping piece outer taper.Its static load anchoring efficiency coefficient is greater than or equal to 95%, the total elongation of assembly part is greater than or equal to 2.0%, anchor mouth friction loss is less than 6%, can withstand 2 million times of cyclic load, when installing, use mining anchor cable tensioning machine, tensioning force is 50%-60% of steel strand breaking force or according to the provisions, must not be reused and mixed with other manufacturers' products.

Description

Technical Field

[0001] This utility model provides a spherical stepped anchor, and particularly relates to a spherical stepped anchor for mining. Background Technology

[0002] Mining anchor cables are key equipment used in mine roadway support engineering to anchor prestressed anchor cables. Their main function is to effectively transfer the prestress on the steel strand to the rock strata or coal seam. By applying and maintaining the preload on the anchor cable, the surrounding rock of the roadway is reinforced, preventing deformation and collapse of the surrounding rock, ensuring construction safety and roadway stability during mining operations. They are an indispensable and important component for maintaining structural stability in mine roadway engineering.

[0003] Existing mining anchor cables typically consist of an anchor ring and a wedge. The anchor ring usually adopts a straight cylindrical or simple conical structure, while the wedge is a common segmented design. The steel strand is clamped by the cooperation between the wedge and the conical hole inside the anchor ring. However, this type of traditional structure has many shortcomings: the end face of the anchor ring is mostly flat, and the cooperation with the tray is simple, which easily leads to stress concentration, affecting the force transmission efficiency and structural durability; there is no dedicated stepped structure on the outside of the anchor ring, making it difficult to adapt to efficient continuous tensioning equipment. The tensioning process requires multiple assembly and disassembly, which is cumbersome and labor-intensive for workers. At the same time, there is a lack of dedicated anchor removal support points, making anchor removal difficult; the clamping structure of the wedge is simple in design, and the distribution of internal teeth and the fit of the taper are not reasonable enough, resulting in uneven clamping force on the steel strand, which easily leads to anchorage shrinkage and affects anchorage reliability; some anchors have poor versatility, and there are large differences in the structure of products from different manufacturers, but there is no clear prohibition against mixing them. Mixing them can easily lead to anchorage failure. In addition, the overall performance in terms of static load anchorage efficiency, fatigue load performance and anchorage friction loss control is poor, making it difficult to meet the high-strength and high-reliability support requirements in complex mining environments. Utility Model Content

[0004] In order to solve the above problems, this application provides a spherical stepped anchor for mining, which solves the problems of unreliable anchoring, stress concentration, complicated tensioning, easy mixing of different types, and large friction loss of existing mining anchors, thereby improving support safety and operation efficiency.

[0005] To solve the above-mentioned technical problems, this utility model provides the following technical solution: a mining spherical stepped anchor, including an anchor ring and three oblique working clamps;

[0006] The anchor ring has a through inner conical hole. The three oblique working clips are spliced ​​together and fit into the inner conical hole of the anchor ring. The inner sides of the three working clips form a channel that fits the steel strand.

[0007] One end of the anchor ring is provided with a spherical end face, which is used to mate with a tray with a spherical groove; the outer side of the anchor ring is provided with an arc-shaped stepped skirt, which extends along the axial direction of the anchor ring and provides a support point for anchor retraction.

[0008] The inner side of the working clamp is provided with internal teeth, which are used to contact the steel strand. Through the positive pressure squeeze of the inner cone hole of the anchor ring and the outer cone of the working clamp, the internal teeth bite the steel strand to prevent it from retracting, thereby achieving anchoring.

[0009] Preferably, both ends of the oblique-cut working clamp are oblique structures, the obliques of the three working clamps are adapted to each other, and after splicing, they form a complete conical structure, and the internal teeth are evenly distributed along the inner axial direction of the working clamp.

[0010] Preferably, it also includes a rubber ring, which is sleeved on the outside of the three oblique working clamp pieces and located between the inner conical hole of the anchor ring and the working clamp pieces, for the purpose of assisting in fixing the working clamp pieces.

[0011] Preferably, the stepped corners of the stepped skirt are rounded, and there are no stress concentration points at the rounded transitions, so as to increase the stress-bearing area of ​​the anchor ring.

[0012] Preferably, the outer taper of the working clamp is adapted to the taper of the inner conical hole of the anchor ring, and the small end of the outer taper of the working clamp faces inward and the large end faces outward, which is consistent with the setting direction of the small end facing inward and the large end facing outward of the inner conical hole of the anchor ring.

[0013] Preferably, it further includes an anchor plate, which is located on one side of the spherical end face of the anchor ring, and the spherical end face of the anchor ring abuts against the anchor plate. The anchor plate is used to support the anchor ring and transfer prestress to the rock strata or coal seam.

[0014] One or more technical solutions provided in the embodiments of this application have at least the following technical effects or advantages compared with the prior art:

[0015] This device utilizes an anchor ring made of high-quality alloy steel and three oblique-cut working clamps. The inner conical hole of the anchor ring mates with the outer conical hole of the working clamps, and the evenly distributed internal teeth on the inner side of the working clamps utilize positive pressure to increase the friction coefficient, ensuring reliable and non-retractable anchoring of the steel strand, thus solving the problem of unreliable anchoring. The spherical end face of the anchor ring mates with a tray with a spherical groove, and the stepped skirt with an arc on the outer side eliminates stress concentration points and increases the stress-bearing area through a rounded transition, solving the problem of stress concentration. The stepped skirt is adapted to... Specialized continuous climbing jacks enable multiple tensioning operations with a single lift, reducing labor intensity and solving the problem of cumbersome tensioning; it is clearly stipulated that anchors from other manufacturers must not be used interchangeably to avoid affecting the anchoring effect due to structural differences, thus solving the problem of easy misuse; its anchor friction loss is less than 6%, static load anchoring efficiency coefficient is ≥95%, the total elongation of the stressed length of the assembly is ≥2.0%, it can withstand 2 million cycles of load, and the cross-sectional area of ​​fatigue failure of the steel strand in the clamping area is not greater than 5% of the total area, comprehensively improving performance to solve related problems.

[0016] Other advantages, objectives and features of this invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination or study, or may be taught from the practice of this invention. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the installation structure of a mining spherical stepped anchorage according to the present invention;

[0018] Figure 2 This is a schematic diagram illustrating the working principle of a mining spherical stepped anchorage according to this utility model.

[0019] Figure 3 This is a cross-sectional view of the anchor ring of a mining spherical stepped anchor of the present invention;

[0020] Figure 4 This is a schematic diagram of the installation of the anchor ring and clamping plate of a mining spherical stepped anchor of this utility model.

[0021] As shown in the figure:

[0022] 1. Anchor ring; 2. Angled working clamp; 3. Steel strand; 4. Rubber ring; 5. Stepped skirt; 6. Anchor plate; 7. Anchor mesh; 8. Tensioning equipment. Detailed Implementation

[0023] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0024] It should be noted that the terms "vertical," "horizontal," "up," "down," "left," "right," and similar expressions used in this article are for illustrative purposes only and do not represent the only possible implementation.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains; the terminology used herein in the description of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention; the term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0026] like Figure 1 and Figure 2 As shown, the core anchoring component of a mining spherical stepped anchor includes an anchor ring 1 and three oblique working wedges 2. The anchor ring 1 has a through inner conical hole. Both ends of the three oblique working wedges 2 are oblique structures and the obliques are mutually compatible. After splicing, they form a complete conical structure and fit into the inner conical hole of the anchor ring 1. The inner side of the wedges forms a channel that fits the steel strand 3. The inner side of the working wedges 2 has internal teeth that are evenly distributed along the axial direction. Through the positive pressure of the inner conical hole of the anchor ring 1 and the outer cone of the working wedges 2, the internal teeth bite the steel strand 3 to prevent it from retracting and achieve anchoring. One end of the anchor ring 1 has a spherical end face for cooperating with a tray with a spherical groove. The outer side of the anchor ring 1 has an arc-shaped stepped skirt 5. The stepped skirt 5 extends along the axial direction of the anchor ring 1 and provides a support point for anchor retraction. At the same time, the outer cone of the working wedges 2 matches the cone of the inner conical hole of the anchor ring 1. The small ends of both face inward and the large ends face outward.

[0027] In this embodiment, the rubber ring 4 is fitted on the outside of the three oblique working clamps 2 and is located between the inner conical hole of the anchor ring 1 and the working clamps 2. It is used to help fix the working clamps 2 and ensure that they maintain a stable splicing state in the inner conical hole of the anchor ring 1. The anchor plate 6 is located on one side of the spherical end face of the anchor ring 1 and abuts against the spherical end face of the anchor ring 1. It is used to support the anchor ring 1 and transfer the prestress to the rock strata or coal seam. The stepped skirt 5 on the outside of the anchor ring 1 adopts a rounded transition at the stepped corner. There is no stress concentration point at the rounded transition to increase the stress-bearing area of ​​the anchor ring 1. From the perspective of implementation, the components work synergistically through precise structural adaptation. The tapered fit and internal tooth design of the anchor ring 1 and the working clamp 2 ensure reliable anchoring of the steel strand 3 and prevent retraction. The fit between the spherical end face and the tray, as well as the stepped skirt 5 with its rounded transition, effectively disperse stress and improve the structure's load-bearing capacity and durability. The stepped skirt 5 provides a stable support point for anchor removal, facilitating operation. The rubber ring 4 enhances the integrity of the working clamp 2, ensuring stability during the anchoring process. The anchor plate 6 effectively transfers prestress. From an innovative perspective, this structural combination solves the problems of unreliable anchoring, stress concentration, and difficulty in anchor removal associated with traditional anchors. Through the complementary functions of each component, it significantly improves the performance and operational efficiency of the anchor, meeting the high strength and high reliability requirements of mine support.

[0028] like Figure 3 and Figure 4 As shown, the mining spherical stepped anchor also includes a rubber ring 4 and an anchor plate 6. The rubber ring 4 is sleeved on the outside of the three oblique working clips 2 and is located between the inner conical hole of the anchor ring 1 and the working clips 2, and is used to assist in fixing the working clips 2. The anchor plate 6 is located on one side of the spherical end face of the anchor ring 1 and abuts against the spherical end face of the anchor ring 1, and is used to support the anchor ring 1 and transfer prestress to the rock strata or coal seam. At the same time, the stepped skirt 5 on the outside of the anchor ring 1 adopts a rounded transition at the stepped corner. There is no stress concentration point at the rounded transition to increase the stress area of ​​the anchor ring 1.

[0029] In this implementation scheme, the spherical end face of the anchor ring 1 mates with the tray with a spherical groove, achieving multi-angle adaptation through spherical contact. This ensures stable fit even on uneven rock or coal seam surfaces, preventing excessive local stress. The three oblique working clamps 2 have their oblique openings mutually adapted to form a complete conical structure. Their inner teeth are evenly distributed axially, applying uniform clamping force when in contact with the steel strand 3, thus improving anchoring stability. The taper of the inner conical hole of the anchor ring 1 precisely matches the taper of the outer cone of the working clamp 2. During tensioning, the positive pressure continuously enhances the biting force of the inner teeth on the steel strand 3, preventing the steel strand 3 from retracting. From an implementation perspective, the rubber ring 4 provides elastic constraint when the working clamp 2 is under stress, preventing displacement due to uneven stress and ensuring consistent anchoring performance. The rounded transition design of the stepped skirt 5 not only eliminates stress concentration but also provides a structural basis for cooperation with a dedicated climbing jack, facilitating continuous tensioning operations and reducing manual labor intensity. From an innovative perspective, the synergistic effect of each structure specifically addresses the problems of poor fit, uneven clamping force, and stress concentration in traditional anchors under complex working conditions. The auxiliary fixing function of the rubber ring 4 enhances the overall structural stability of the anchor. The cooperation between the anchor plate 6 and the spherical end face improves the prestress transfer efficiency. The design of the stepped skirt 5 balances structural strength and ease of operation, making the anchor more adaptable to the high-intensity and high-frequency use requirements in mining support.

[0030] In the actual use of this device, existing drilling equipment (such as pneumatic rock drills or hydraulic drilling rigs) is also required to drill installation holes suitable for steel strands in rock strata or coal seams; hole cleaning tools (such as high-pressure air guns or hole cleaning brushes) are used to clean rock cuttings and debris from the borehole to ensure the smooth insertion of the steel strands; steel strand cutting tools (such as abrasive wheel cutters) are used to cut steel strands to the appropriate length according to support requirements; and tension monitoring instruments (such as pressure sensors or force gauges) are used in conjunction with mining anchor cable tensioning equipment for precise control. Tensioning force is required. In addition, to prevent the anchorage from rusting in the humid mine environment, anti-rust treatment materials (such as anti-rust oil or zinc coating) are used to treat the surface of the anchor ring and the beveled working wedge. The high-quality alloy steel used for the anchor ring and the beveled working wedge can be 40CrNiMoA (a high-strength alloy structural steel with good hardenability and mechanical properties), and the rubber ring can be made of nitrile rubber (oil-resistant, wear-resistant and adaptable to temperature changes in the mine) to ensure the stability and service life of each component under complex working conditions.

[0031] Specifically, in actual construction, a mining hydraulic drilling rig or pneumatic rock drill must first be used to drill an installation hole in the rock or coal seam according to the designed hole depth and diameter. After drilling, the rock powder and debris inside the hole are cleaned with a high-pressure air gun. Then, 1860MPa grade steel strands with a diameter of Ф21.8mm are cut according to the hole depth, and a guide cap is fitted onto one end of the steel strand. The steel strand is then threaded through the hole from one end to the other end using a threading machine to a suitable length. Next, an anchor mesh is laid on the surface of the coal and rock layer at the hole opening. The anchor plate is placed tightly against the anchor mesh and aligned with the center of the hole. The anchor ring is then fitted onto the exposed end of the steel strand, with the spherical end face of the anchor ring facing the anchor plate. Then, three oblique working clips are evenly distributed along the steel strand and pushed into the inner conical hole of the anchor ring, ensuring that the inner teeth of the clips are in contact with the steel strand. Finally, the pressure bar of the mining anchor tensioning machine 8 is aligned with the stepped skirt of the anchor ring, and the operation is performed. Tensioning device 8 deflects the pressure bar and squeezes the side of the anchor ring to achieve connection. The pump station is started to drive the middle cylinder of the tensioning machine to extend, causing the tool clamps inside the anchor ring of the tensioning machine to loosen the steel strand and apply tension load. When the tension force reaches 50%-60% of the breaking force of the steel strand, the load is kept stable. At this time, the working clamps bite the steel strand under the action of the conical hole inside the anchor ring. The retraction force of the steel strand causes the clamps to hug itself again, thereby preventing the steel strand from retracting. Then, the pressure bar is operated to release the fixation of the anchor ring and remove the tensioning device 8. Finally, the excessively long exposed part of the steel strand is cut off with a cutting machine. Anti-rust paint is applied to the outside of the anchor ring and the exposed steel strand, and the anchor is sealed with quick-setting cement to complete the entire anchoring operation. The anchor ring and the oblique working clamps are made of 40CrNiMoA alloy structural steel through forging and heat treatment. The rubber ring is made of nitrile rubber to adapt to the humid environment of the mine.

[0032] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be determined by the claims.

Claims

1. A spherical stepped anchor for mining, characterized in that: Includes anchor ring (1) and three angled working clamps (2); The anchor ring (1) has a through inner conical hole. The three oblique working clips (2) are spliced ​​together and adapted to the inner conical hole of the anchor ring (1). The inner side of the three working clips (2) forms a channel adapted to the steel strand (3). One end of the anchor ring (1) is provided with a spherical end face, which is used to cooperate with a tray with a spherical groove; the outer side of the anchor ring (1) is provided with an arc-shaped stepped skirt (5), which extends along the axial direction of the anchor ring (1) and provides a support point for anchor retraction; The inner side of the working clamp (2) is provided with internal teeth, which are used to contact the steel strand (3). Through the positive pressure of the inner cone hole of the anchor ring (1) and the outer cone of the working clamp (2), the internal teeth bite the steel strand (3) to prevent it from retracting, thereby achieving anchoring.

2. The mining spherical stepped anchorage according to claim 1, characterized in that: Both ends of the oblique-cut working clamp (2) are oblique structures. The obliques of the three working clamps (2) are adapted to each other and are spliced ​​together to form a complete conical structure. The internal teeth are evenly distributed along the inner axial direction of the working clamp (2).

3. The mining spherical stepped anchorage according to claim 1, characterized in that: It also includes a rubber ring (4), which is sleeved on the outside of the three oblique working clips (2) and located between the inner conical hole of the anchor ring (1) and the working clip (2) to assist in fixing the working clip (2).

4. The mining spherical stepped anchorage according to claim 1, characterized in that: The stepped corner of the stepped skirt (5) is rounded, and there is no stress concentration point at the rounded transition, so as to increase the stress area of ​​the anchor ring (1).

5. The mining spherical stepped anchorage according to claim 1, characterized in that: The outer cone of the working clip (2) is adapted to the cone of the inner cone hole of the anchor ring (1). The small end of the outer cone of the working clip (2) faces inward and the large end faces outward, which is consistent with the setting direction of the small end of the inner cone hole of the anchor ring (1) facing inward and the large end facing outward.

6. The mining spherical stepped anchorage according to claim 1, characterized in that: It also includes an anchor plate (6), which is located on one side of the spherical end face of the anchor ring (1), and the spherical end face of the anchor ring (1) abuts against the anchor plate (6). The anchor plate (6) is used to support the anchor ring (1) and transmit prestress to the rock strata or coal seam.

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