Anchoring chuck for coal mine anchor cable test

Abstract

The utility model discloses a kind of split type anchoring chuck for coal mine anchor cable test, belong to the technical field of mine support testing equipment. Including two half-round chuck A and half-round chuck B of matched arrangement, two split;In chuck bottom, the protruding mounting card station for butting with testing machine is provided, the outer periphery of mounting card station is less than the outer periphery of chuck;In the center of anchoring chuck, the anchor cable mounting hole that passes through anchoring chuck is provided;Four fixed bolt holes are evenly distributed on the chuck outside the periphery of mounting card station. Modular split design is adopted, after test is completed, only need to loosen fixed bolt, chuck can be quickly disassembled, anchor cable sample after damage is directly taken out from testing machine in integrity, completely avoid the security risk brought by traditional method needs to be carried out on-site cutting in the narrow space of testing machine. Greatly simplify test procedure, reduce the labor intensity of operator, significantly improve test efficiency and safety.

Description

Technical Field

[0001] This utility model relates to the technical field of mine support testing equipment, specifically an anchoring chuck for coal mine anchor cable testing, which is particularly suitable for anchor cable static load performance testing, and especially suitable for high-frequency, large-volume anchor cable testing scenarios. Background Technology

[0002] In the field of coal mine geological disaster prevention and control, anchor cables, as key support components, must undergo rigorous testing to verify their mechanical properties. Anchor chucks, as important components of the testing equipment, currently have the following technical defects: Existing anchor chucks are integral structures. After the test, the broken anchor cable typically only breaks one wire to release the stress and complete the test, leaving the remaining wires loose and unbroken. Each wire must be cut with a handheld cutting machine to remove the damaged anchor cable from the anchor chucks at both ends of the testing machine. This requires cutting operations within the confined space of the testing machine after the test, posing a serious safety hazard; the cutting process generates sparks and metal debris, polluting the testing environment; a single sample removal takes more than 15 minutes, resulting in low efficiency; repeated cutting operations accelerate equipment wear and increase maintenance costs. Utility Model Content

[0003] To address the problems existing in the prior art, this utility model provides an anchoring chuck for coal mine anchor cable testing. Using this anchoring chuck, operation is safe, efficient, and convenient for coal mine anchor cable testing.

[0004] The technical solution of this utility model is: an anchoring chuck for coal mine anchor cable testing, comprising: two paired semi-circular chucks A and B, which are separate. A semi-circular hole penetrating the chuck is provided at the center of the contact surface of each of the two semi-circular chucks. In use, the two semi-circular chucks combine to form an annular chuck structure, forming an anchor cable mounting hole penetrating the chuck at its center. A protruding mounting platform for docking with a testing machine is provided at the bottom of the chuck. The outer circumference of the mounting platform is smaller than that of the chuck and fits tightly with the testing machine's slot. Four bolt holes for installation are evenly distributed on the chuck outside the periphery of the mounting platform.

[0005] Preferably, the mounting plate and the semi-circular chuck are an integral structure.

[0006] Preferably, the anchor cable mounting hole at the center of the anchor chuck is matched with the anchor cable.

[0007] Preferably, the four fixing bolt holes are symmetrically distributed at 90° and have a diameter of Φ20±0.1mm.

[0008] Preferably, the chuck is made of 40Cr alloy structural steel that has undergone quenching and tempering heat treatment, and its hardness is HRC42-45; the surface has a dense oxide film of 3-5μm formed by bluing and anti-rust treatment.

[0009] Preferably, the thickness of the chuck is 60±0.5mm.

[0010] Preferably, the mounting plate protrusion height is 9mm, and the fitting clearance with the testing machine slot is ≤0.1mm.

[0011] Preferably, each semi-circular chuck is fixed by two sets of M20 high-strength bolts and fixing bolt holes, with a bolt preload torque of 280-320 N·m.

[0012] The innovation of this invention lies in its modular, split design of the chuck, breaking through the structural limitations of traditional integral chucks. After the test, the chuck can be quickly disassembled simply by loosening the fixing bolts, allowing the damaged anchor cable sample to be completely removed from the testing machine. This completely avoids the safety hazards associated with on-site cutting within the confined space of the testing machine, a method that requires traditional methods. This design significantly simplifies the testing process, reducing the time for a single test by approximately 80%, while also reducing the workload of operators and significantly improving testing efficiency and safety. Furthermore, this invention features a compact and reasonable structure, convenient installation, and a secure clamping mechanism that is not prone to slippage, making it suitable for testing anchor cables of different specifications. Actual on-site testing in the laboratory has verified that this anchoring chuck operates stably and reliably, is easy to operate and maintain, and has high potential for widespread application.

[0013] The beneficial effects of this utility model are: 1. Significantly improved safety: After the test, the sample can be directly removed by simply disassembling the two semi-circular chucks on both sides, completely avoiding the safety hazards of cutting operations in the confined space of the testing machine, such as sparks and equipment interference, which are required by traditional methods. This reduces the risk of related accidents by 100% and greatly protects the safety of the test personnel.

[0014] 2. Breakthrough improvement in work efficiency: Traditional methods require about 15 minutes for on-site cutting and cleaning, while this solution can complete sample disassembly in just 3 minutes, reducing the single operation time by 80% and improving the overall test efficiency by more than 50%, which is especially suitable for high-frequency, large-volume anchor cable testing scenarios.

[0015] 3. Optimized ease of operation: The modular split structure allows for quick assembly and disassembly by simply tightening or loosening bolts, avoiding the physical exertion required for traditional cutting operations, reducing labor intensity, and minimizing reliance on auxiliary equipment.

[0016] 4. Reliable and durable structure: The chuck is made of 40Cr alloy steel, which is quenched and bluing, and has both high strength and corrosion resistance. The optimized design of the inner wall contact surface ensures that the anchor cable is firmly clamped and there is no risk of slippage. The service life is more than twice that of traditional chucks.

[0017] 5. Reduced overall costs: Eliminating the need for cutting equipment wear and tear and subsequent waste disposal, long-term use can reduce equipment maintenance costs and manpower input, resulting in significant economic benefits.

[0018] 6. Wide adaptability: Field tests have verified that this design is suitable for testing needs of anchor cables of different specifications. It is flexible in installation and highly compatible, and has high promotional value. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 yes Figure 1 Cross-sectional view of the chuck: Figure 3 This is an exploded view of the anchor chuck.

[0020] In the diagram: 1. Semi-circular chuck A; 2. Semi-circular chuck B; 3. Anchor cable mounting hole; 4. Mounting platform; 5. Bolt hole. Detailed Implementation

[0021] To enable those skilled in the art to more clearly understand the technical solution of this utility model, the present utility model will be further described clearly and completely below in conjunction with the disclosed drawings and embodiments. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit this disclosure or its application or use. Based on the embodiments in this disclosure, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this disclosure.

[0022] Example 1 like Figures 1-3 As shown, the anchoring chuck for coal mine anchor cable testing in this embodiment is a split-type structure. The split-type chuck comprises a pair of semi-circular chucks A1 and B2, which are separate units but are combined to form a complete annular chuck structure during use. A raised mounting platform 4 for docking with the testing machine is provided at the center of the chuck surface. The mounting platform and the semi-circular chuck are integrally formed. The outer circumference of the mounting platform 4 is smaller than the outer circumference of the chuck and fits tightly with the slot of the testing machine. An anchor cable mounting hole 3 penetrating the anchoring chuck is provided at the center of the anchoring chuck. Four fixing bolt holes 5 are evenly distributed on the chuck outside the periphery of the mounting platform 4.

[0023] like Figure 2 As shown, the bottom surface of the anchor chuck is provided with a mounting plate 4, which is 9mm high and has an H7 / g6 transition fit with the testing machine's slot. The contact surface of the testing machine is hardened to HRC45.

[0024] In this embodiment, the four fixing bolt holes are symmetrically distributed at 90°, and the hole diameter is Φ20±0.1mm. The chuck is made entirely of 40Cr alloy steel, which undergoes quenching and tempering heat treatment to achieve a hardness of HRC42-45. The surface is treated with bluing for rust prevention, forming a dense oxide film of 3-5μm with a standard thickness of 60±0.5mm. The two semi-circular chucks, A1 and B2, are precision-machined. When combined, the inner bore of the 40Cr alloy steel semi-circular chucks A1 and B2 forms an anchor cable mounting hole 3 with a diameter of Φ25±0.05mm, suitable for anchor cables with diameters of Φ15.2-21.6mm. The surfaces of the chucks are precision ground to a surface roughness of Ra1.6 to ensure a tight fit between the mating surfaces.

[0025] The mounting plate at the bottom of the chuck has a clearance of ≤0.1mm with the testing machine's slot, ensuring installation accuracy. An anchor cable mounting hole 3 runs through the center of the chuck, with a diameter suitable for anchor cables of Φ15.2-21.6mm, meeting the testing requirements of different specifications. A high-strength fixing system consists of four sets of Φ20±0.1mm fixing bolt holes symmetrically distributed at 90°, using M20 high-strength bolts to secure the chuck together, with a preload torque of 280-320 N·m, ensuring reliable connection. A laser-etched specification marking area on the outer circumference of the chuck includes key parameters such as material, hardness, and rated load.

[0026] The specific usage instructions are as follows: (1) Installation stage: Push the two half chucks into the slots of the testing machine to ensure that the mounting plate 4 is fully in place. Install the high-strength bolts and tighten them to 300 N·m according to the torque gradient. The chucks on both sides of the testing machine are installed to form an integral chuck. Then, pass the anchor cable to be tested through the anchor cable installation center hole 3 of the left and right chucks of the testing machine. The exposed ends of the anchor cables on both sides are ≥200 mm. Finally, install the anchors as required, and the test can be started according to the requirements of MT / T942-2005 "Mining Anchor Cables".

[0027] (2) Post-test processing: After removing the bolts on the right side of the testing machine, remove the right side chuck, and then remove the left side (hydraulic cylinder side) half of the chuck. The broken anchor cable can then be easily removed by sliding it from the right side of the testing machine. Check the wear of the chuck's inner hole. After a cumulative use of 200 tests, it needs to be re-grinded.

[0028] The laser marking area is engraved using a 20W fiber laser and includes information on material, hardness, and rated load.

[0029] The above embodiments fully cover all the technical features of the claims and provide achievable process parameters and operating specifications.

[0030] Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of this disclosure, and are not intended to limit them. Although the preferred embodiments have provided a detailed description of the technical solutions, those skilled in the art should understand that modifications can still be made to the specific implementation methods of this disclosure or equivalent substitutions can be made to some technical features, all of which should be covered within the scope of the technical solutions claimed in this disclosure.

Claims

1. An anchoring chuck for testing coal mine anchor cables, characterized in that, It includes: Two semi-circular chucks A (1) and B (2) are paired and set up separately. Each semi-circular chuck has a semi-circular hole that penetrates the chuck at the center of the contact surface of the two semi-circular chucks. When in use, the two semi-circular chucks are combined to form an annular chuck structure. An anchor cable installation hole (3) that penetrates the anchor chuck is formed at the center of the anchor chuck. A raised mounting plate (4) for docking with the testing machine is provided at the bottom of the chuck. The outer circumference of the mounting plate (4) is smaller than the outer circumference of the chuck and fits tightly with the chuck groove of the testing machine. Four bolt holes (5) for installation are evenly distributed on the chuck outside the periphery of the mounting plate (4).

2. The anchoring chuck for coal mine anchor cable testing according to claim 1, characterized in that: The mounting plate (4) and the semi-circular chuck are an integral structure.

3. The anchoring chuck for coal mine anchor cable testing according to claim 1, characterized in that: The anchor cable mounting hole (3) at the center of the anchor chuck is fitted with the anchor cable.

4. The anchoring chuck for coal mine anchor cable testing according to claim 1, characterized in that... The four bolt holes (5) used for installation are symmetrically distributed at 90°.

5. The anchoring chuck for coal mine anchor cable testing according to claim 1, characterized in that: The chuck is made of 40Cr alloy structural steel that has undergone quenching and tempering heat treatment, with a hardness of HRC42-45; the surface has a dense oxide film of 3-5μm formed by bluing and anti-rust treatment.

6. The anchoring chuck for coal mine anchor cable testing according to claim 1, characterized in that: The thickness of the chuck is 60±0.5mm.

7. The anchoring chuck for coal mine anchor cable testing according to claim 1, characterized in that: The protrusion height of the mounting plate (4) is 9mm, and the fitting clearance with the testing machine slot is ≤0.1mm.

8. The anchoring chuck for coal mine anchor cable testing according to claim 1, characterized in that: Each semi-circular chuck is fixed by two sets of M20 high-strength bolts and fixing bolt holes (5), with a bolt preload torque of 280-320 N·m.

9. The anchoring chuck for coal mine anchor cable testing according to claim 1, characterized in that: The outer circumference of the chuck is also marked with a specification marking area containing information on material, hardness, and rated load.

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