A method for single-sided operation of cross-anchor cables in coal pillars during goaf excavation.

Abstract

This invention discloses a single-sided, through-and-through anchor cable for coal pillars in goaf-side excavation roadways. It includes an anchor cable body, a steel plate, and a hinged assembly at one end of the anchor cable body; the hinged assembly has an umbrella-shaped structure. During installation, the anchor cable is pushed towards the goaf side, and then pulled towards the face roadway until the high-manganese carbon steel spring breaks and the hinged assembly is tightly pressed against the coal pillar surface. This invention achieves bidirectional reinforcement of a reserved coal pillar on one side of the goaf-side excavation roadway, solving the problem of reinforcement work not being possible on the goaf side, and greatly improving the bearing capacity and stability of the roadway support coal pillar, thus possessing broad practical value.

Description

Technical Field

[0001] This invention relates to a reinforcing anchor cable, specifically a single-sided through-and-through anchor cable for coal pillars in goaf tunneling. Background Technology

[0002] Goaf-side excavation technology refers to excavating roadways entirely along the edge of the goaf or leaving only a very narrow coal pillar. This involves arranging the roadway in a low-stress field on one side of a small coal pillar, facilitating roadway protection and reducing deformation. The key to this technology is controlling the width of the coal pillar. The important purpose of leaving a small coal pillar is to isolate the roadway from the goaf, preventing water and harmful gases from entering the roadway. However, the small coal pillar plays a decisive role in the maintenance of the roadway.

[0003] With the gradual maturation of goaf-side excavation technology, the study of the width and stability of small coal pillars has become an increasingly important issue. Since goaf-side excavation relies on small coal pillars to support the roadway roof, it is necessary to strengthen the support for these pillars. The existing through-bolt technology involves pre-burying bolts in the previous working face, and then pulling them out during the excavation of the next working face to achieve through-bolt operation. However, due to the low precision in the width of the small coal pillars, the through-bolts cannot function properly. Furthermore, by the time the next working face begins production, the goaf area of ​​the previous working face is no longer suitable for bolt installation. Considering that the goaf side of the small coal pillar in goaf-side excavation is already closed, construction can only proceed from the new working face side. The existing through-bolts cannot achieve through-bolt reinforcement of the small coal pillar under the condition of construction on one side and closure on the other; therefore, no suitable through-bolts are available.

[0004] Existing technologies cannot achieve bidirectional reinforcement by constructing from only one side. Summary of the Invention

[0005] To address the aforementioned problems, this invention aims to provide a single-sided operation through-anchor cable for coal pillars in goaf excavation, which can achieve bidirectional reinforcement of small coal pillars in goaf excavation. It can be completed by constructing only on one side of the small coal pillar, thus solving the problem of sealing the goaf (i.e., the other side of the small coal pillar) when bidirectionally reinforcing small coal pillars.

[0006] This invention provides a single-sided operation through-and-through anchor cable for coal pillars in goaf excavation; it includes an anchor cable body and a steel plate, with a hinge assembly at one end of the anchor cable body and an anchor cable body lock and an anchor cable body tray at the other end; the hinge assembly has an umbrella-shaped structure.

[0007] The hinge assembly includes a hinge and a sleeve. The sleeve is welded and fixed on a steel plate. The hinge is located on the outside of the sleeve with the sleeve as the center. The hinge consists of four rods that can be opened and closed. One end of the hinge is fixed to the pivot of the sleeve, and the other end is connected to the anchor cable body through a spring. One side of the spring is welded to the hinge, and the other side is welded to the steel ring set on the anchor cable.

[0008] The anchor cable is placed in the small coal pillar hole. Under the tension of the spring, the hinge is tightly attached to the anchor cable body. Pulling the anchor cable body to one side of the working face causes the spring to break. The hinge is at 90° with the anchor cable body. After opening, bidirectional anchoring is achieved. With pre-tightening force, bidirectional fastening can be achieved.

[0009] The tension of the spring is less than the preload, and it breaks and opens before reaching the preload.

[0010] The steel plate serves to limit the opening angle of the hinge, acting as a limiter; after the hinge is opened, it provides anchoring to the goaf side; the sleeve connects to the hinge via a rotating shaft.

[0011] During installation, push the anchor cable towards the goaf side until it reaches the goaf side, then pull the anchor cable towards the working face roadway until the high manganese carbon steel spring breaks and the hinge assembly can be pressed tightly against the coal pillar surface.

[0012] The aforementioned hinge is hinged to the sleeve fixed on the anchor cable.

[0013] The anchor cable body and the sleeve are connected by an external threaded rod; the end of the anchor cable body located in the goaf is connected to the sleeve of the hinge assembly through the external threaded rod.

[0014] The aforementioned high-manganese carbon steel springs are welded and fixed to the steel ring and hinge on the anchor cable body, respectively.

[0015] The aforementioned connector is welded and fixed to the steel plate.

[0016] The beneficial effects of this invention are:

[0017] (1) In this invention, the high manganese carbon steel spring is broken by applying pre-tightening force, the hinge assembly is unfolded and tightly attached to the coal pillar by the steel plate limit, thus realizing bidirectional reinforcement of the reserved coal pillar on one side of the goaf tunnel;

[0018] (2) After the small coal pillar is reinforced by the two-way reinforcement of the present invention, its bearing capacity will be greatly improved, which greatly enhances the bearing capacity and stability of the small coal pillar. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of the present invention, showing the single-sided operation of the coal pillar in the goaf excavation with the through anchor cable in the open state.

[0020] Figure 2 This is a schematic diagram of the structure of the present invention, showing the single-sided operation of the coal pillar along the goaf in the closed state of the through anchor cable;

[0021] Figure 3 This is a schematic diagram illustrating the application of the device of the present invention after it passes through the coal pillar and opens the anchor.

[0022] Figure 4 This is a schematic diagram illustrating the application of the device of the present invention when it does not pass through a coal pillar;

[0023] Figure 5 This is a schematic diagram illustrating the application of the present invention. Figure 1 (Left view)

[0024] Figure 6 This is a schematic diagram illustrating the application of the present invention. Figure 2 (Left view)

[0025] In the diagram, 1 is the anchor cable body, 2 is the anchor cable body lock, 3 is the anchor cable body tray, 4 is the steel ring, 5 is the spring, 6 is the external threaded rod, 7 is the hinge, 8 is the socket, 9 is the steel plate, and 10 is the small coal pillar. Detailed Implementation

[0026] To better understand the present invention, the embodiments of the present invention will be explained in detail below with reference to the accompanying drawings.

[0027] like Figures 1-6 As shown, a single-sided operation through-anchor cable for coal pillars in a goaf tunnel includes an anchor cable body 1 and a steel plate 9. One end of the anchor cable body 1 is provided with a hinge assembly, and the other end is provided with an anchor cable body lock 2 and an anchor cable body tray 3; the hinge assembly has an umbrella-shaped structure.

[0028] The hinge assembly includes a hinge 7 and a sleeve 8. The sleeve 8 is welded and fixed on the steel plate 9. The hinge 7 is arranged on the outside of the sleeve 8 with the sleeve as the center. The hinge 7 consists of four hinge rods evenly arranged in a circumferential direction. One end of the hinge 7 is fixed to the pivot of the sleeve 8, and the other end is connected to the anchor cable body 7 through a spring 5. The spring 5 controls the hinge rods to realize the opening and closing operation.

[0029] Furthermore, the spring 5 is a high-manganese carbon steel spring, with one side of the spring welded to the hinge and the other side welded to the steel ring 4 fixedly installed on the anchor cable body.

[0030] The tension of the spring is less than the preload, and it breaks and opens before reaching the preload. Under the tension of the spring, the hinge is tightly attached to the anchor cable body and pulls the anchor cable body to one side of the working face, causing the spring to break. The hinge is at 90° with the anchor cable body. After opening, bidirectional anchoring is achieved, and bidirectional fastening is achieved after the preload is applied.

[0031] The steel plate is located on the far right of the through-anchor cable device, which can limit the opening angle of the hinge; after the hinge is opened to 90°, it has an anchoring effect on the goaf side.

[0032] The anchor cable body 1 and the sleeve 8 are connected by an external threaded rod 6; the end of the anchor cable body 1 located in the goaf is connected to the sleeve 8 of the aforementioned hinge assembly through the external threaded rod 6.

[0033] The construction process of this invention is as follows:

[0034] like Figure 3 and Figure 4As shown, a hole is drilled into the small coal pillar 10 from one side of the working face roadway; the sleeve 8 is connected and fixed by the external threaded rod 6, and the steel plate 9 is welded and fixed at the end of the external threaded rod 6 by welding. The width of the steel plate 9 is smaller than the diameter of the hole; the high manganese carbon steel spring 5 is welded and fixed to the steel ring 4 and the hinge 7 by welding; the steel ring 4 is fixed to the anchor cable body 1 by extrusion (the steel ring 4 is an extrusion sleeve, and the extrusion force makes the steel ring plastically deformed and tightly engaged with the anchor cable).

[0035] On the working face side, the high-manganese carbon steel spring 5 of the single-sided operating through-anchor cable is compressed and inserted into the borehole, so that the hinge 7 is located in the borehole on the goaf side. The high-manganese carbon steel spring 5 is released from its compressed state and rebounds, pulling the anchor cable body 1 towards the working face side until the high-manganese carbon steel spring 5 breaks, and the hinge 7 opens (as shown). Figure 1 (As shown) The steel plate 9 is tightly attached to the hinge 7 until the steel plate 9 is tightly attached to the small coal pillar 10. Anchor cable lock 2 and anchor cable tray 3 are set on the working face side; Lock: Reinforces the small coal pillar; Tray: Transmits the thrust generated by the locking torque of the lock to the small coal pillar to generate the initial anchoring force.

[0036] In the single-sided operation of the through-hole anchor cable construction proposed in this invention, if the drilling position and the rockfall position do not conflict, the cable can be installed directly. If the drilling position and the rockfall position conflict, a grooving drill bit is used to drill a hole in the rockfall area of ​​the goaf before installation. "No conflict in rockfall position" means that in a near-horizontal coal seam, the rockfall will not affect the drilling position, and the two will not overlap. Conflicts generally occur in inclined coal seams, where the rockfall and drilling positions may overlap. In this case, a grooving drill bit is needed to enlarge the hole on the goaf side (i.e., the other side of the coal pillar).

[0037] The single-sided operation through-cable proposed in this invention can achieve bidirectional reinforcement of small coal pillars. Construction can be completed only on the working face side of the small coal pillar, solving the problem of goaf closure during bidirectional reinforcement of coal pillars. It also greatly improves the bearing capacity and stability of the coal pillars in the roadway protection, and has broad practical value.

Claims

1. A single-sided operation of a through-anchor cable for coal pillars in a goaf-running roadway, characterized in that: It includes an anchor cable body and a steel plate. One end of the anchor cable body is equipped with a hinge assembly, and the other end is equipped with an anchor cable body lock and an anchor cable body tray. The hinge assembly has an umbrella-shaped structure. The hinge assembly includes a hinge member and a sleeve member. The sleeve member is welded and fixed to a steel plate. The hinge member is positioned around the sleeve member and is located on its outer side. The hinge member consists of four hinge rods evenly arranged in a circumferential direction. One end of the hinge member is fixed to the pivot of the sleeve member, and the other end is connected to the anchor cable body through a spring. The spring controls the hinge rods to achieve the opening and closing operation. The tension of the spring is less than the preload, and it breaks before reaching the preload. Under the tension of the spring, the hinge member is tightly attached to the anchor cable body. Pulling the anchor cable body towards the working surface causes the spring to break. The hinge member is at a 90° angle to the anchor cable body. After opening, bidirectional anchoring is achieved, and bidirectional fastening is achieved after the preload is applied. The steel plate is located on the far right of the through-anchor cable device, which can limit the opening angle of the hinge; after the hinge is opened to 90°, it has an anchoring effect on the goaf side.

2. The single-sided operation of the through-anchor cable for coal pillars in roadway excavation according to claim 1, characterized in that: The spring is a high-manganese carbon steel spring, with one side welded to the hinge and the other side welded to a steel ring fixed on the anchor cable body.

3. The single-sided operation of the through-anchor cable for coal pillars in roadway excavation according to claim 1, characterized in that: The anchor cable body is located at one end in the goaf and is connected to the sleeve of the aforementioned hinge assembly via an externally threaded rod.

4. The single-sided operation of the through-anchor cable for coal pillars in roadway excavation according to claim 1, characterized in that: The anchor cable body and the sleeve connection are provided with an external threaded rod.

5. A method for using the single-sided operation of the through-anchor cable in a coal pillar during goaf excavation as described in any one of claims 1 to 4, characterized in that... Includes the following steps: (1) Drill holes in the small coal pillar from one side of the working face roadway; connect and fix the sleeve through the external thread rod, and weld the steel plate to the end of the external thread rod by welding. The width of the steel plate is smaller than the diameter of the hole; weld the high manganese carbon steel spring to the steel ring and the hinge respectively by welding; fix the steel ring to the anchor cable body by extrusion. (2) On the working face side, compress the high manganese carbon steel spring of the single-sided operation through anchor cable and put it into the borehole so that the hinge is located in the borehole on the goaf side. The high manganese carbon steel spring is released from the compressed state and rebounds. Pull the anchor cable body towards the working face side until the high manganese carbon steel spring breaks. The hinge opens and is close to the steel plate until the hinge and the steel plate are close to the small coal pillar. Set the anchor cable body lock and anchor cable body tray on the working face side.

6. The method of using the single-sided operation of the coal pillar through the goaf excavation as described in claim 5, characterized in that: During installation, push the anchor cable towards the goaf side until it reaches the goaf side, then pull the anchor cable towards the working face roadway until the high manganese carbon steel spring breaks and the hinge assembly can be pressed tightly against the coal pillar surface.

7. The method of using the single-sided operation of the coal pillar through the goaf excavation as described in claim 5, characterized in that: During the single-sided operation of the through-anchor cable construction, if the drilling position does not conflict with the rockfall position, it can be installed directly. If the drilling position conflicts with the rockfall position, a grooving drill bit is used to drill a hole in the rockfall area of ​​the goaf before installation.

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