Anchor rod auxiliary device for coal mine tunnel

Abstract

The invention relates to the technical field of anchor rod grouting, and discloses an anchor rod auxiliary device for a coal mine roadway, the anchor rod auxiliary device comprises an anchor rod, and further comprises a plugging assembly arranged on the anchor rod, the plugging assembly comprises a carrying ring coaxially arranged on the anchor rod, and a plurality of drainage holes are formed in the carrying ring in the circumferential direction of the carrying ring; the axial section of the drainage hole is in a horn shape, the size of a hole opening, close to the grouting direction, of the drainage hole is smaller than that of a hole opening, away from the grouting direction, of the drainage hole, the drainage hole is matched with an anchor rod for exhausting in the working state, a flexible ring is fixedly connected to an inner ring of the carrying ring, and a plurality of metal wires are installed in the flexible ring at equal intervals. And the flexible ring is radially contracted based on the rotary motion of the anchor rod, so that the anchor rod is gradually locked. Through the arrangement of the plugging assembly and the cooperation assembly, when the grouting hole is subjected to liquid returning, through the curved surface guiding of the synchronous ring and the trumpet-shaped characteristic of the drainage hole, the blocking probability of an exhaust passage is reduced when the anchor rod exhausts, and it is ensured that the exhaust process is continuous and smooth.

Description

Technical Field

[0001] This invention relates to the field of anchor bolt grouting technology, specifically to an anchor bolt auxiliary device for coal mine roadways. Background Technology

[0002] In the coal mine production environment, grouting anchors are inserted into the borehole after drilling is completed. Grout is injected into the borehole through its hollow cavity to seal and reinforce the borehole wall. The core of its support effectiveness lies in the fullness and density of the grout in the borehole.

[0003] Retractable grouting, as a commonly used process, requires the anchor bolt to rotate slightly and retract a certain distance along the borehole axis during the grouting process to improve the uniformity and fullness of the grouting. However, this process has significant problems in practical applications. For short to medium distance grouting, it is difficult to maintain a stable grouting pressure during the rotation and retraction of the anchor bolt, which makes it difficult for the grout to effectively penetrate into the surrounding rock fissures and weakens the strengthening effect on the surrounding rock.

[0004] The lack of proper sealing treatment leads to pressure fluctuations and discontinuous slurry flow. Unexploded gas is easily left at the top of the borehole, forming gas chambers. After the slurry solidifies, defects such as incomplete filling and discontinuity occur. These problems directly reduce the effective anchoring length of the anchor bolts and decrease the reliability of the anchoring, thereby affecting the overall stability of the support system and posing a potential threat to the long-term safety of the roadway. Summary of the Invention

[0005] The purpose of this invention is to provide an anchor bolt auxiliary device for coal mine roadways to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a rock bolt auxiliary device for coal mine roadways, comprising a rock bolt, and further comprising:

[0007] A sealing assembly is mounted on an anchor bolt. The sealing assembly includes a carrier ring coaxially mounted on the anchor bolt. The carrier ring has several drainage holes circumferentially arranged inside it. The axial cross-section of the drainage holes is funnel-shaped, and the size of the holes near the grouting direction is smaller than that away from the grouting direction. In the working state, it works with the anchor bolt to release air. A flexible ring is fixedly connected to the inner ring of the carrier ring. Several metal wires are installed at equal intervals inside the flexible ring. The rotational movement of the anchor bolt causes the flexible ring to contract radially, gradually locking the anchor bolt. A rubber ring is fixedly connected to the outer edge of the carrier ring.

[0008] A coordinating component is installed on the anchor bolt. The coordinating component includes a synchronization ring fixedly connected to the anchor bolt. The surface of the synchronization ring facing the slurry is curved. An annular airbag is fixedly connected to the synchronization ring near the small opening of the discharge hole. An annular plate is fixedly connected to the surface of the annular airbag. The maximum outer diameter of the annular airbag is smaller than the maximum outer diameter of the synchronization ring.

[0009] It also includes a measuring element, which includes a pressure-sensing tube. One end of the pressure-sensing tube passes through the rubber ring and is fixedly connected to it, and the opening at this end communicates with the grouting area. The other end of the pressure-sensing tube is connected to a pressure sensor via a thread for real-time detection of grouting pressure.

[0010] The pressure-inducing tube extends through the end opening of the rubber ring to a position adapted to the grouting operation surface.

[0011] In the initial state, there is a gap between the annular airbag and the surface of the flexible ring. In the working state, the annular airbag deforms and comes into contact with the surface of the flexible ring.

[0012] There is a gap between the surface of the annular plate and the surface of the carrier ring. In the working state, the annular plate abuts against the carrier ring, so that the annular airbag deforms toward its radial outward.

[0013] The rubber ring is coaxially arranged with the anchor rod, and the outer circumferential surface of the rubber ring is always in contact with the inner wall of the grouting hole.

[0014] Compared with the prior art, the beneficial effects of the present invention are:

[0015] By setting up sealing and coordinating components, when backflow occurs in the grouting hole, the synchronous ring curved surface guide and the funnel-shaped characteristics of the discharge hole reduce the probability of blockage in the venting passage during anchor bolt venting, ensuring the continuous smooth flow of the venting process.

[0016] Furthermore, as the anchor bolt rotates and retracts, the interaction between the metal wire and the bolt body causes radial contraction, achieving gradual locking of the anchor bolt. This ensures that the anchor bolt is effectively fixed even at a very small rotation angle, reducing disturbance to the surrounding rock. At the same time, as the anchor bolt retracts, the flexible rings form an orderly ring-shaped stack within a limited space, gradually filling the grouting channel. When the grout level rises to the set height and the anchor bolt retracts to its maximum design stroke, the stacked flexible rings will seal the drainage hole, forming the main sealing surface.

[0017] Furthermore, by using pressurized annular airbags, flexible filling and channel sealing are achieved, eliminating the risk of grout leakage and backflow, and ensuring that a full and dense grout body is formed inside the borehole. Attached Figure Description

[0018] Figure 1This is a diagram of the device of the present invention in its initial state before grouting.

[0019] Figure 2 This is a schematic diagram of the cross-sectional structure of the anchor bolt portion of the present invention;

[0020] Figure 3 This is a schematic diagram of the axial cross-section of the anchor bolt of the present invention. Figure 1 ;

[0021] Figure 4 This is a schematic diagram of the axial cross-section of the anchor bolt of the present invention. Figure 2 .

[0022] In the diagram: 100, anchor bolt; 110, carrier ring; 111, drainage hole; 112, flexible ring; 113, metal wire; 114, rubber ring; 1141, pressure tapping pipe; 1142, pressure sensor; 120, synchronization ring; 121, annular airbag; 122, annular plate. Detailed Implementation

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

[0024] To achieve the above objectives, the present invention discloses the following technical solution: a rock bolt auxiliary device for coal mine roadways, comprising a rock bolt 100, and further comprising:

[0025] A sealing assembly is installed on the anchor bolt 100. The sealing assembly includes a carrier ring 110 coaxially installed on the anchor bolt 100. The carrier ring 110 has several drainage holes 111 opened around its circumference. The axial cross section of the drainage holes 111 is funnel-shaped, and the size of the hole near the grouting direction is smaller than the size of the hole away from the grouting direction. In the working state, it cooperates with the anchor bolt 100 to vent air. A flexible ring 112 is fixedly connected to the inner ring of the carrier ring 110. Several metal wires 113 are installed at equal intervals inside the flexible ring 112. The rotational movement of the anchor bolt 100 causes the flexible ring 112 to contract radially, which gradually locks the anchor bolt 100. A rubber ring 114 is fixedly connected to the edge of the outer surface of the carrier ring 110.

[0026] The coordinating component is installed on the anchor bolt 100. The coordinating component includes a synchronization ring 120 fixedly connected to the anchor bolt 100. The surface of the synchronization ring 120 facing the slurry is curved. An annular airbag 121 is fixedly connected to the synchronization ring 120 near the small opening of the discharge hole 111. An annular plate 122 is fixedly connected to the surface of the annular airbag 121. The maximum outer diameter of the annular airbag 121 is smaller than the maximum outer diameter of the synchronization ring 120.

[0027] The working principle and beneficial effects of this embodiment are as follows:

[0028] First, see 2- Figure 4 When the anchor bolt 100 is inserted into the drilled grouting hole, the initial state is as follows: Figure 1 As shown, the anchor bolt 100 is then operated to introduce grout into its interior for grouting.

[0029] Secondly, during grouting, the rubber ring 114 confines the anchor bolt 100 inside the hole, effectively sealing the grouting environment. When the grout carries gravel and air towards the outside of the hole for venting, the gravel may move towards the discharge hole 111 along with the grout. As the gravel moves towards the discharge hole 111, it will first come into contact with the curved surface of the synchronization ring 120, i.e. the grout-facing surface. The gravel will be guided and dispersed in a conical manner, reducing the risk of clogging the small port of the discharge hole 111. At the same time, the air after grouting rises with the grout level and is gradually discharged outward from the discharge hole 111.

[0030] At the same time, as the anchor bolt 100 rotates at a small angle and is pulled into the grouting hole, the flexible ring 112 between the carrier ring 110 and the synchronization ring 120 begins to stack on each other. The small-amplitude rotation of the anchor bolt 100 causes multiple metal wires 113 to move closer to the axis of the anchor bolt 100. As the synchronization ring 120 gradually approaches the carrier ring 110, the flexible ring 112 folds into a ring shape, gradually narrowing the exhaust channel. Until the anchor bolt 100 completely stops rotating and retracts, the flexible ring 112 contacts the curved annular plate 122. The annular plate 122 and the synchronization ring 120 will press the annular airbag 121 tightly, so that the annular airbag 121 fills the gap of the folded flexible ring 112, and the vent hole 111 is blocked, and exhaust stops.

[0031] During use, the curved surface of the synchronization ring 120 acts as a "guide plate," using the kinetic energy of the grout to guide the gravel to the periphery, reducing the risk of blockage in the discharge hole 111. Simultaneously, the funnel-shaped structure of the discharge hole 111, with a small opening at the end facing the grout flow, prevents large pieces of gravel from entering the channel. If debris smaller than the inlet enters, the gradually expanding chamber provides buffering and diffusion space for the debris, further reducing the possibility of blockage in the discharge hole 111. During the initial rotation and retraction of the anchor bolt 100, the flexible ring 112 folds and the channel gradually narrows, allowing air to escape in an orderly manner, while simultaneously increasing the grout flow resistance. Towards the end of the anchor bolt 100's rotation, it becomes a sealed pressure-maintaining system, with the annular plate 122 and synchronization ring 120 providing rigid compression. The annular airbag 121 fills irregular gaps, compensating for deformation gaps. The metal wire 113, gradually moving towards the axis of the anchor bolt 100, also gradually locks off vibrations during the grouting process.

[0032] In a further embodiment, a measuring element is also included, which includes a pressure-sensing tube 1141. One end of the pressure-sensing tube 1141 passes through and is fixedly connected to a rubber ring 114, and the opening at this end communicates with the grouting area. The other end of the pressure-sensing tube 1141 is connected to a pressure sensor 1142 via a thread for real-time detection of grouting pressure.

[0033] The end opening of the pressure inlet tube 1141, which passes through the rubber ring 114, extends to a position that is compatible with the grouting operation surface.

[0034] In the initial state, there is a gap between the annular airbag 121 and the surface of the flexible ring 112. In the working state, the annular airbag 121 deforms and comes into contact with the surface of the flexible ring 112.

[0035] There is a gap between the surface of the annular plate 122 and the surface of the carrier ring 110. In the working state, the annular plate 122 abuts against the carrier ring 110, so that the annular airbag 121 deforms toward its radial outward.

[0036] The rubber ring 114 is coaxially arranged with the anchor rod 100, and the outer circumferential surface of the rubber ring 114 is always in contact with the inner wall of the grouting hole.

[0037] First refer to 1- Figure 4 During the grouting process of the anchor bolt 100, the pressure pipe 1141 guides the grouting pressure status to the pressure sensor 1142 in real time, so that personnel can observe the internal state of the grouting hole in a timely manner. After the anchor bolt 100 is grouted, while waiting for the grout inside the hole to solidify, the pressure sensor 1142 is removed. When the next grouting process is executed, the pressure sensor 1142 is installed on the pressure pipe 1141 and the grouting operation is repeated.

[0038] During use, continuous operation is required. If a pressure sensor 1142 is needed for each grouting, the cost will increase. Through the "one device for multiple uses" design, one pressure sensor 1142 can be used repeatedly for multiple anchor bolt positions, achieving the goal of reducing costs and increasing efficiency.

[0039] The contents not described in detail in this description are existing technologies known to those skilled in the art. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A bolt auxiliary device for coal mine roadways, comprising a bolt (100), characterized in that, Also includes: A sealing assembly is installed on the anchor rod (100). The sealing assembly includes a carrier ring (110) coaxially installed on the anchor rod (100). The carrier ring (110) has several drainage holes (111) opened in its circumference. The axial cross section of the drainage holes (111) is trumpet-shaped, and the size of the hole near the grouting direction is smaller than the size of the hole away from the grouting direction. In the working state, it cooperates with the anchor rod (100) to vent air. A flexible ring (112) is fixedly connected to the inner ring of the carrier ring (110). Several metal wires (113) are installed at equal intervals inside the flexible ring (112). Based on the rotational movement of the anchor rod (100), the flexible ring (112) generates radial contraction, which gradually locks the anchor rod (100). A rubber ring (114) is fixedly connected to the outer edge of the carrier ring (110). A coordinating component is provided on the anchor bolt (100). The coordinating component includes a synchronization ring (120) fixedly connected to the anchor bolt (100). The surface of the synchronization ring (120) facing the slurry is curved. An annular airbag (121) is fixedly connected to the synchronization ring (120) near the small opening of the discharge hole (111). An annular plate (122) is fixedly connected to the surface of the annular airbag (121). The maximum outer diameter of the annular airbag (121) is smaller than the maximum outer diameter of the synchronization ring (120).

2. The anchor bolt auxiliary device for coal mine roadways according to claim 1, characterized in that: It also includes a measuring element, which includes a pressure-sensing tube (1141). One end of the pressure-sensing tube (1141) passes through the rubber ring (114) and is fixedly connected to it, and the opening at this end is connected to the grouting area. The other end of the pressure-sensing tube (1141) is connected to a pressure sensor (1142) by a thread for real-time detection of grouting pressure.

3. The anchor bolt auxiliary device for coal mine roadways according to claim 2, characterized in that: The pressure inlet tube (1141) extends through the end opening of the rubber ring (114) to a position adapted to the grouting operation surface.

4. The anchor bolt auxiliary device for coal mine roadways according to claim 3, characterized in that: In the initial state, there is a gap between the annular airbag (121) and the surface of the flexible ring (112). In the working state, the annular airbag (121) deforms and comes into contact with the surface of the flexible ring (112).

5. The anchor bolt auxiliary device for coal mine roadways according to claim 4, characterized in that: There is a gap between the surface of the annular plate (122) and the surface of the carrier ring (110). In the working state, the annular plate (122) abuts against the carrier ring (110) so that the annular airbag (121) deforms toward its radial outward.

6. The anchor bolt auxiliary device for coal mine roadways according to claim 5, characterized in that: The rubber ring (114) is coaxially arranged with the anchor rod (100), and the outer circumferential surface of the rubber ring (114) is always in contact with the inner wall of the grouting hole.

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