Stirring and pre-tightening integrated left-hand thread glass fiber reinforced plastic anchor rod and mounting method

Abstract

The stirring and pre-tightening integrated left-hand thread glass fiber reinforced plastic anchor rod comprises a rod body, and an external thread of the rod body is machined into a left-hand thread; the anchor rod further comprises a supporting plate piece, and the inner diameter of the supporting plate piece is larger than the outer diameter of the rod body. The tail end of the nut piece is provided with a hexagonal tail matched with the stirrer of the drilling machine, and the hexagonal tail is provided with a through hole; the torsion bar is matched with the through hole; the torsion bar is assembled into the through hole, the supporting plate piece and the nut piece are sequentially installed from the tail end of the rod body till the torsion bar abuts against the tail end of the rod body, the drill stirrer is connected with the hexagonal tail in a clamped mode to rotationally push the rod body into an anchor rod hole, and the drill stirrer drives the nut piece to rotationally push after the torsion bar is abraded and broken. And the rod body is pre-tightened until the head end of the nut part extrudes the supporting plate part. The device is matched with a common drilling machine, stirring and pre-tightening of the glass fiber reinforced plastic anchor rod can be integrally installed, and the procedure is simplified.

Description

Technical Field

[0001] The invention belongs to the technical field of anchor rod support, and in particular relates to a left-handed fiberglass anchor rod with stirring and pre-tightening function and an installation method thereof. Background Art

[0002] FRP anchor rods have the characteristics of light material, high tensile strength, low shear strength, and can be cut and broken. They are suitable for supporting the side of surrounding rock tunnels and mine shafts in simple stress environments, and are widely used in coal mine roadway support.

[0003] At present, most of the FRP anchor rods are used for the side coal wall support of the coal mining face cutting and mining, and a small part is used for the side coal wall support of the solid coal tunnel working face in a simple stress environment. Taking advantage of the cuttable characteristics of FRP anchor rods, the coal mining machine directly cuts the FRP anchor rods during the mining of the working face, eliminating the process of workers pulling metal anchor rods at the end of the working face, reducing labor intensity and improving mining efficiency. At the same time, the coal mining machine does not produce sparks when cutting FRP anchor rods, reducing the risk of fire and explosion underground, and making the working face coal mining environment safer. After the FRP anchor rods are cut and mixed into the coal blocks, they are not easy to get stuck in the scraper or scratch the transport belt, and are more friendly to coal mining and transportation equipment.

[0004] It is now required that the tunnel support of non-coal mines be aligned with that of coal mines to ensure the safety of mine support. The overall stress environment of non-coal mines is simpler than that of coal mines, and the surrounding rock strength is significantly higher than that of coal mine tunnels. Based on the characteristics of FRP anchor rods and their application experience in coal mines, FRP anchor rods are introduced into special tunnels or chambers in non-coal mines for mining tunnel support.

[0005] Most non-coal mines mainly use pipe-seam metal anchor support. Metal anchors have high shear strength. When metal anchors are mixed into ore bodies that need to be crushed, pulverized, and sorted for crushing, it is easy to damage the equipment. The equipment maintenance time is long, which restricts production efficiency. The metal material also has a certain impact on the ore sorting.

[0006] Some copper and iron mines have chambers in the ore body, the f value of the ore body can reach 10-15, the surrounding rock of the tunnel chamber is stable, the stress environment is simple, and the service time of the chamber is short, generally less than 1 year, which is suitable for FRP anchor support. After the chamber is supported by FRP anchors, the ore is dropped by blasting. After the FRP anchors are blasted, they are transported with the ore body into crushers and other equipment for crushing and pulverization. Due to the characteristics of FRP anchors that can be cut and crushed, the damage to crushers and other equipment can be greatly reduced, the equipment maintenance time can be greatly shortened, and production efficiency can be improved.

[0007] However, in actual applications, it was found that when the FRP anchor rods suitable for supporting the side of coal mine tunnels were used for supporting the roof of non-coal mine tunnels, the FRP anchor rods did not match the YT28 drilling rigs commonly used in non-coal mines, and the right-handed threads of conventional FRP anchor rods did not match the counterclockwise rotation of the YT28 drilling rigs. In addition, the mixing of the anchoring agent for FRP anchor rods and the pre-tightening of FRP anchor rods in coal mine construction were divided into two processes, which was complicated and not conducive to the construction of the roof of the tunnel. Problems with conventional FRP anchor rods:

[0008] 1) Fiberglass anchor rods are not compatible with common drilling rigs:

[0009] Conventional FRP anchors have full-length right-hand threads, but the YT28 drill rigs commonly used in non-coal mines have a non-adjustable counterclockwise reversal mode. The right-hand thread does not match the counterclockwise reversal drill rig, making it impossible to construct and install conventional FRP anchors.

[0010] 2) The two processes of anchoring agent mixing and FRP anchor bolt pre-tightening are independent and complicated, which is not conducive to rapid construction and installation:

[0011] After the anchor hole is drilled, put the anchoring agent in the hole. First, use a threaded agitator to screw it on the tail of the FRP anchor. The agitator is connected to the anchor drilling rig. Start the anchor drilling rig, tighten the agitator on the FRP anchor, rotate and push the FRP anchor to stir the anchoring agent. After the specified stirring time, stop the drilling rig, wait for the anchoring agent to solidify, then remove the agitator to complete the anchoring of the FRP anchor.

[0012] After completing the anchoring of the FRP anchor rod, install ordinary plastic nuts and plastic support plates in sequence at the tail of the FRP anchor rod, and then tighten the nuts manually with a wrench or with a drill to complete the pre-tightening of the FRP anchor rod.

[0013] The above two processes are independent and more complicated than the integrated construction of ordinary threaded steel anchor bolts and pre-tightening, which is not conducive to workers' operation and affects the support efficiency. After the fiberglass anchor bolts are anchored, the agitator is disassembled. Since non-coal mines mostly use YT28 drilling rigs for construction, the YT28 drilling rigs cannot be reversed to directly disassemble the agitator from the tunnel roof, and workers need to manually disassemble the agitator, which is inconvenient to operate and also poses safety risks in high-altitude operations.

[0014] 3) The tunnel surface is uneven, the support plate is not close to the rock surface, and the FRP anchor rod is susceptible to shear force, which affects the performance of the FRP anchor rod:

[0015] Non-coal mine tunnels are mostly excavated by blasting, and the cross-section of the tunnels is often uneven. Conventional fiberglass anchor rods are equipped with ordinary plastic nuts and plastic support plates that do not fit the rock surface of the tunnel. The fiberglass anchor rods are not perpendicular to the rock surface, and the rod body is easily damaged by shear force. The bearing capacity of the rod body is limited, which is not conducive to controlling the surrounding rock of the tunnel. Summary of the invention

[0016] The present invention aims at solving the problems in the prior art and proposes the following technical solutions:

[0017] A left-handed fiberglass anchor bolt with stirring and pre-tightening, comprising a rod body, wherein the outer thread of the rod body is processed into a left-handed thread; the anchor bolt further comprises:

[0018] A support plate member, wherein the inner diameter of the support plate member is larger than the outer diameter of the rod body;

[0019] A nut, the tail end of which is provided with a hexagonal tail adapted to the drilling rig agitator, and the hexagonal tail is provided with a through hole;

[0020] A torsion bar, wherein the torsion bar is adapted to the through hole;

[0021] The torsion bar is assembled into the through hole, and the support plate and the nut are successively installed from the tail end of the rod body until the torsion bar is against the tail end of the rod body. The drilling rig agitator engages the hexagonal tail to rotate and push the rod body into the anchor hole. After the torsion bar is worn and broken, the drilling rig agitator drives the nut to rotate and advance until the head end of the nut squeezes the support plate to achieve pre-tightening of the rod body.

[0022] As a preferred embodiment of the above technical solution, the support plate member includes a support plate body, and a protrusion is coaxially arranged on one side of the support plate body close to the nut member, and the protrusion is directly opposite to the nut head at the head end of the nut member.

[0023] As a preferred embodiment of the above technical solution, a concave groove is provided on one side of the protrusion close to the hexagonal tail, and the nut head is in the shape of a mushroom head.

[0024] As a preferred embodiment of the above technical solution, a limited step is provided between the nut head and the hexagonal tail.

[0025] As a preferred embodiment of the above technical solution, the torsion bar is made of a plastic material with a torque resistance of 50 to 80 N·m.

[0026] An installation method is applied to the above-mentioned left-handed threaded fiberglass anchor rod with stirring and pre-tightening, and the installation method comprises the following steps:

[0027] S1. Pre-drilling: construct anchor holes with corresponding hole diameters and hole depths according to the size specifications of the rod body;

[0028] S2. Pre-installation: install the torsion bar into the through hole, put the support plate on the rear end of the rod body, and then install the head section of the nut piece toward the support plate at the rear end of the rod body until the torsion bar rests against the rear end of the rod body, thus completing the assembly of the FRP anchor rod;

[0029] S3, installation stage: the anchor drilling rig is equipped with a stirrer that matches the hexagonal tail, the anchoring agent is put into the anchor hole, the front end of the assembled fiberglass anchor is put into the anchor hole, the hexagonal tail is placed in the stirrer, the anchor drilling rig is started, the nut and the rod body are rotated synchronously as a whole and pushed into the bottom of the anchor hole while stirring the anchoring agent at the same time;

[0030] S4, pre-tightening stage: the torsion bar is worn and broken, the rotation of the drilling rig drives the nut to rotate and push forward, against the support plate, and then the rotation of the drilling rig is stopped. After waiting for the anchor agent to solidify, the drilling rig is disassembled to complete the installation of a left-handed threaded fiberglass anchor rod with mixing and pre-tightening.

[0031] The beneficial effects of the present invention are:

[0032] 1. The fiberglass anchor rod body of the present invention has a full-length left-hand thread, which matches the counterclockwise rotation of the drilling rig commonly used in non-coal mines and has better adaptability;

[0033] 2. The rod body of the present invention is provided with a mounting support plate and a nut member, and a torsion bar is installed on the through hole. The torsion bar is against the tail end of the rod body. When the rod body stirs the anchoring agent b in the anchor hole a, the torsion bar limits the rotation of the nut member, so that the rod body and the nut member rotate synchronously as a whole to achieve the purpose of stirring the anchoring agent b. As the rotation time of the drilling rig increases, the torsion bar will wear and break due to the torque resistance. After the torsion bar is broken, the drilling rig continues to rotate to drive the nut member to rotate forward and push against the support plate member to achieve the effect of pre-tightening the rod body, so that the rod body can achieve stirring and pre-tightening integration, simplifying the process;

[0034] 3. The rod body of the present invention is pre-tightened by the support plate and the nut member extruding each other. The nut head is pressed against the concave groove to make the rod body, the support plate and the rock surface contact vertically as much as possible, thereby optimizing the force of the FRP anchor rod and facilitating the performance of the FRP anchor rod. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 The figure shows a structural diagram of the parts of a left-handed fiberglass anchor with stirring and pre-tightening in one embodiment;

[0036] Figure 2 The diagram shows a structural diagram of a support plate member and a nut member in a left-handed fiberglass anchor rod with stirring and pre-tightening in one embodiment;

[0037] Figure 3 The diagram shows a structural schematic diagram of a left-handed fiberglass anchor rod with stirring and pre-tightening integrated in the embodiment when it initially enters the anchor rod hole;

[0038] Figure 4 The figure shows a structural schematic diagram of a left-handed threaded FRP anchor rod in the pre-tightening stage with stirring and pre-tightening in an embodiment;

[0039] Figure 5Shown is a schematic structural diagram of a left-handed threaded fiberglass anchor rod with stirring and pre-tightening integrated in an embodiment after installation.

[0040] In the figure: a, anchor hole; b, anchor; 10, rod body; 20, support plate member; 21, support plate body; 22, protrusion; 23, concave groove; 30, nut member; 31, nut head; 32, limiting step; 33, hexagonal tail; 34, through hole; 40, torsion bar. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solution and advantages of the embodiments of the present invention more clear, the technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments.

[0042] Example

[0043] like Figure 1 As shown, a left-handed threaded FRP anchor rod with stirring and pre-tightening integrated therein comprises a rod body 10, the outer thread of the rod body 10 being processed as a left-handed thread; the rod body of the FRP anchor rod of the present invention is a full-length left-handed thread, which matches the counterclockwise reversal of the drilling rigs commonly used in non-coal mines and has better adaptability.

[0044] like Figure 2 As shown, the anchor rod also includes:

[0045] A support plate 20, wherein the inner diameter of the support plate 20 is greater than the outer diameter of the rod body 10;

[0046] A nut 30, the tail end of which is provided with a hexagonal tail 33 adapted to the drilling rig agitator, and a through hole 34 is provided on the hexagonal tail 33;

[0047] The torsion bar 40 is matched with the through hole 34 ; the torsion bar 40 is made of plastic material with a torque resistance of 50 to 80 N·m.

[0048] like Figure 3-Figure 5 As shown, a support plate member 20 and a nut member 30 are installed on the rod body 10 of the present invention, and a torsion bar 40 is installed on the through hole 34. The torsion bar 40 is against the rear end of the rod body 10. When the rod body 10 stirs the anchor b in the anchor hole a, the existence of the torsion bar 40 limits the rotation of the nut member 30, so that the rod body 10 and the nut member 30 rotate synchronously as a whole to achieve the purpose of stirring the anchor b. As the rotation time of the drilling rig increases, the torsion bar 40 resists the torque and will wear and break the torsion bar 40. After the torsion bar 40 is broken, the drilling rig continues to rotate to drive the nut member 30 to rotate forward and push against the support plate member 20 to achieve the effect of pre-tightening the rod body 10, so that the rod body 10 can achieve integrated stirring and pre-tightening, thereby simplifying the process.

[0049] like Figure 2 , Figure 5As shown, the support plate member 20 includes a support plate body 21, and a protrusion 22 is coaxially arranged on one side of the support plate body 21 close to the nut member 30, and the protrusion 22 is directly opposite to the nut head 31 at the head end of the nut member 30; a concave groove 23 is arranged on one side of the protrusion 22 close to the hexagonal tail 33, and the nut head 31 is in the shape of a mushroom head.

[0050] The rod body 10 of the present invention is pre-tightened by the support plate 20 and the nut 30 squeezing each other, and the nut head 31 is pressed against the concave groove 23 to make the rod body 10, the support plate 20 and the rock surface contact vertically as much as possible, thereby optimizing the force of the FRP anchor rod and facilitating the performance of the FRP anchor rod.

[0051] A limiting step 32 is provided between the nut head 31 and the hexagonal tail 33. By providing the limiting step 32, the nut head 31 can be better engaged with the drilling rig agitator, and the stability of the engagement transmission between the hexagonal tail 33 and the agitator is further improved.

[0052] An installation method is applied to the above-mentioned left-handed threaded fiberglass anchor rod with stirring and pre-tightening, and the installation method comprises the following steps:

[0053] S1, pre-drilling: construct anchor holes with corresponding hole diameters and hole depths according to the size specifications of the rod body 10;

[0054] S2, pre-installation: install the torsion bar 40 into the through hole 34, put the support plate 20 on the rear end of the rod body 10, and then install the head section of the nut 30 toward the support plate 20 at the rear end of the rod body until the torsion bar 40 is against the rear end of the rod body 10, and the assembly of the fiberglass anchor is completed;

[0055] S3, installation stage: the anchor drilling machine is equipped with a stirrer that matches the hexagonal tail 33, the anchoring agent is put into the anchor hole, the front end of the assembled fiberglass anchor is put into the anchor hole, the hexagonal tail 33 is placed in the stirrer, the anchor drilling machine is started, the nut 30 and the rod body 10 are rotated synchronously as a whole and pushed into the bottom of the anchor hole while stirring the anchoring agent;

[0056] S4, pre-tightening stage: the torsion bar 40 is worn and broken, the rotation of the drilling rig drives the nut part 30 to rotate and advance, against the support plate part 20, and then the rotation of the drilling rig is stopped, and the drilling rig is disassembled after waiting for the anchoring agent to solidify, completing the installation of a left-handed threaded fiberglass anchor rod with stirring and pre-tightening.

[0057] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them.

Claims

1. A left-handed fiberglass anchor bolt with stirring and pre-tightening function, comprising a rod body (10), characterized in that: The external thread of the rod body (10) is processed into a left-hand thread; the anchor rod further comprises: A support plate member (20), wherein the inner diameter of the support plate member (20) is greater than the outer diameter of the rod body (10); A nut member (30), wherein the tail end of the nut member (30) is provided with a hexagonal tail (33) adapted to the drilling rig agitator, and the hexagonal tail (33) is provided with a through hole (34); A torsion bar (40), wherein the torsion bar (40) is adapted to the through hole (34); The torsion bar (40) is assembled into the through hole (34), and the support plate (20) and the nut (30) are successively installed from the rear end of the rod body (10) until the torsion bar (40) is against the rear end of the rod body (10), and the drilling rig agitator is engaged with the hexagonal tail (33) to rotate and push the rod body (10) into the anchor hole. After the torsion bar (40) is worn and broken, the drilling rig agitator drives the nut (30) to rotate and push until the head end of the nut (30) squeezes the support plate (20) to achieve pre-tightening of the rod body (10).

2. The stirring and pre-tightening integrated left-handed threaded FRP anchor rod according to claim 1, characterized in that: The support plate member (20) comprises a support plate body (21), and a protrusion (22) is coaxially arranged on one side of the support plate body (21) close to the nut member (30), and the protrusion (22) is directly opposite to the nut head (31) at the head end of the nut member (30).

3. The stirring and pre-tightening integrated left-handed threaded FRP anchor rod according to claim 2, characterized in that: A concave groove (23) is provided on one side of the protruding portion (22) close to the hexagonal tail (33), and the nut head (31) is in the shape of a mushroom head.

4. The stirring and pre-tightening integrated left-handed threaded FRP anchor rod according to claim 1, characterized in that: A limiting step (32) is provided between the nut head (31) and the hexagonal tail (33).

5. The stirring and pre-tightening integrated left-handed threaded FRP anchor bolt according to claim 1, characterized in that: The torsion bar (40) is made of plastic material with a resistance torque of 50 to 80 N·m.

6. An installation method, characterized in that: The installation method is applied to a left-handed threaded FRP anchor rod with stirring and pre-tightening as described in any one of claims 1 to 5, and the installation method comprises the following steps: S1, pre-drilling: constructing anchor holes with corresponding hole diameters and hole depths according to the size specifications of the rod body (10); S2, pre-installation: install the torsion bar (40) into the through hole (34), put the support plate (20) through the rear end of the rod body (10), and then install the head section of the nut member (30) toward the support plate (20) at the rear end of the rod body until the torsion bar (40) abuts against the rear end of the rod body (10), thereby completing the assembly of the fiberglass anchor rod; S3, installation stage: the anchor drilling machine is equipped with a stirrer that matches the hexagonal tail (33), the anchoring agent is put into the anchor hole, the front end of the assembled fiberglass anchor is put into the anchor hole, the hexagonal tail (33) is placed in the stirrer, the anchor drilling machine is started, the nut (30) and the rod body (10) are rotated synchronously as a whole and pushed into the bottom of the anchor hole while stirring the anchoring agent; S4, pre-tightening stage: the torsion bar (40) is worn and broken, the rotation of the drilling rig drives the nut member (30) to rotate and push against the support plate member (20), and then the rotation of the drilling rig is stopped, and the drilling rig is disassembled after waiting for the anchoring agent to solidify, completing the installation of a left-handed threaded fiberglass anchor rod with stirring and pre-tightening.

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