Quantitative characterization method for size stability of synthetic fiber mesh

Abstract

The invention provides a quantitative characterization method for the size stability of a synthetic fiber mesh. Based on the influence of material characteristics, structural design, external force and external environment conditions on the size of a synthetic fiber mesh, the size of the synthetic fiber mesh is obviously changed after the mesh is dynamically fatigued. The synthetic fiber mesh is subjected to a dynamic fatigue test in a stretching mode, and the ratio of the displacement difference between the fatigue cycle for a certain number of times and the displacement difference when the pre-tension is reached for the first time to the effective length of a clamp is used as a method for evaluating the size stability of the synthetic fiber mesh. The method can quantitatively characterize the size stability of the synthetic fiber mesh, and the smaller the ratio is, the better the size stability of the synthetic fiber mesh is.

Description

Technical Field

[0001] This invention belongs to the field of fiber mesh characterization technology, and relates to the characterization of synthetic fiber mesh, specifically to a quantitative characterization method for the dimensional stability of synthetic fiber mesh. Background Technology

[0002] The dimensional stability of synthetic fiber netting directly affects the performance and catch yield of fisheries, and is mainly influenced by material properties, structural design, external forces, and environmental conditions. Regarding materials, the elastic modulus and creep properties of synthetic fibers directly affect the dimensional stability of the netting. For example, high-density polyethylene netting may undergo 0.5% to 2% plastic deformation under long-term load. In terms of structural design, knotted netting is prone to wear due to the protruding knots, resulting in poor mesh dimensional stability; knotless netting (such as warp-knitted and twisted netting) is more dimensionally stable and has higher wear resistance due to the absence of knots. Regarding external forces, in trawls, the mesh size is determined by the length of the mesh feet. If the knots slip or the netting wears, the mesh feet may shorten, leading to a smaller mesh size and thus affecting the dimensional stability of the netting.

[0003] In addition, factors such as wire diameter, mesh shape, and assembly process also affect the dimensional stability of the mesh: wire diameter, wear or stretching of the wire can change the diameter, affecting mesh stability and thus causing changes in the overall size of the mesh; mesh shape, different shapes such as square and hexagonal meshes deform to different degrees after being stressed, which may cause local or overall changes in the size of the mesh; during assembly, uneven tension during sewing or knotting can cause the mesh to deform due to uneven load distribution, affecting the size of the mesh.

[0004] In actual use, the size of synthetic fiber mesh will change significantly due to external forces, so there is an urgent need for corresponding characterization methods to measure the size change of synthetic fiber mesh. However, there is currently no way to quantitatively characterize the size change of synthetic fiber mesh to assess its stability. Summary of the Invention

[0005] This invention addresses the aforementioned problems by providing a quantitative characterization method for the dimensional stability of synthetic fiber meshes. The core technical principle is as follows: Since the dimensions of synthetic fiber meshes are influenced by material properties, structural design, external forces, and environmental conditions, their dimensions change significantly after dynamic fatigue. By conducting dynamic fatigue tests on the synthetic fiber meshes in tensile mode, the ratio of the displacement difference after a certain number of fatigue cycles to the effective length of the clamping device at the first point of pre-tension is used to evaluate the dimensional stability of the synthetic fiber meshes. This method can quantitatively characterize the dimensional stability of synthetic fiber meshes; the smaller the ratio, the better the dimensional stability of the synthetic fiber mesh.

[0006] Based on this, the present invention provides a quantitative characterization method for the dimensional stability of synthetic fiber mesh. The synthetic fiber mesh to be tested is cut into samples of a certain size and subjected to dynamic fatigue test in tensile mode. The ratio of the displacement difference after a certain number of fatigue cycles to the effective length of the clamp when the pre-tension is first reached is used as the standard for evaluating the dimensional stability of the synthetic fiber mesh. The smaller the ratio, the better the dimensional stability of the mesh.

[0007] Preferably, the sample preparation method is as follows: referring to the national standard GB / T 4925-2008 Test Method for Strength and Elongation at Break of Synthetic Fiber Net for Fishing, the synthetic fiber net is cut into samples with a width of 4.5 mesh and a length of about 30 cm (ensuring that the effective length between the clamps is 20 cm).

[0008] Preferably, the quantitative characterization method of the present invention is suitable for characterizing the dimensional stability of synthetic fiber meshes made of various materials, such as polyethylene meshes, polyamide multifilament meshes, polyamide monofilament meshes, and ultra-high molecular weight polyethylene meshes. In a preferred embodiment of the present invention, quantitative characterization of meshes of different materials, sizes, and processes has been successfully performed.

[0009] Preferably, the instrument used for dynamic fatigue testing is a fatigue testing machine.

[0010] Furthermore, the test process adopted sinusoidal waveform load control, the test load (maximum load) was 10%~80% of the corresponding mesh breaking strength, the minimum load / maximum load (stress ratio) was 0.1, and the loading frequency was 1~10 Hz.

[0011] Preferably, the method for determining the pretension of the mesh sample is as follows: referring to the provisions of GB / T 6965-2004, the pretension value of each mesh or warp (dimension) is equal to the self-weight of 250m of mesh length.

[0012] Preferably, the number of dynamic fatigue tests is 1,000 to 100,000.

[0013] The beneficial protections and effects of this invention are as follows:

[0014] This invention evaluates the dimensional stability of synthetic fiber mesh by subjecting it to dynamic fatigue testing in tensile mode. The ratio of the displacement difference after a certain number of fatigue cycles to the effective length of the clamping device when the pretension is first applied is used as the dimensional stability of the synthetic fiber mesh. This method can be implemented using a single fatigue testing machine, requiring conventional equipment and employing a simple measurement method, which facilitates large-scale application and characterizes the quality stability of different batches of mesh. Attached Figure Description

[0015] Figure 1 The results show the quantitative characterization process of the dimensional stability of the UHMWPE mesh in Example 1.

[0016] Figure 2 The results show the quantitative characterization process of the dimensional stability of the UHMWPE mesh in Example 2.

[0017] Figure 3 The results show the quantitative characterization process of the dimensional stability of the UHMWPE mesh in Example 3.

[0018] Figure 4 The results show the quantitative characterization process of the dimensional stability of the polyethylene knotted mesh in Example 4.

[0019] Figure 5 The results show the quantitative characterization process of the dimensional stability of the PA knotted mesh in Example 5.

[0020] Figure 6 The results show the quantitative characterization process of the dimensional stability of the PA knotted mesh in Example 6.

[0021] Figure 7 The results show the quantitative characterization process of the dimensional stability of the PA knotted mesh in Example 7. Detailed Implementation

[0022] The implementation of the present invention will be described in detail below with reference to the embodiments of the present invention. The following embodiments are implemented under the premise of the technical solution of the present invention, and detailed implementation methods and specific operation processes are given. However, the protection scope of the present invention is not limited to the following embodiments.

[0023] Unless otherwise specified, all materials and reagents used in the following examples are commercially available.

[0024] Example 1

[0025] UHMWPE mesh with specifications of 1600D / 7 strands - 50 mm, manufactured by Huizhou Yichen Wire Mesh Technology Co., Ltd., was selected. Following the national standard GB / T 4925-2008 "Test Method for Strength and Elongation at Break of Synthetic Fiber Fishing Nets", the synthetic fiber mesh was cut into samples with a width of 4.5 mesh and a length of approximately 30 cm (effective length between clamps was 20 cm). The longitudinal breaking strength of the mesh was tested to be 6440.8 N. The test process used sinusoidal waveform load control, with the test load (maximum load) being 10% of the corresponding mesh breaking strength, the minimum load / maximum load (stress ratio) being 0.1, the loading frequency being 1 Hz, and the number of dynamic fatigue tests being 10000. Figure 1 The ratio of the displacement difference after 10,000 fatigue cycles to the first time the pretension was reached to the effective length of the clamp is used as a characterization method for the dimensional stability of synthetic fiber mesh. The ratio is d=(39.849-36.430) / 200=0.017.

[0026] Example 2

[0027] UHMWPE mesh with specifications of 1600D / 7 strands - 50 mm, manufactured by Huizhou Yichen Wire Mesh Technology Co., Ltd., was selected. Following the national standard GB / T 4925-2008 "Test Method for Strength and Elongation at Break of Synthetic Fiber Fishing Nets", the synthetic fiber mesh was cut into samples with a width of 4.5 mesh and a length of approximately 30 cm (effective length between clamps was 20 cm). The longitudinal breaking strength of the mesh was tested to be 6440.8 N. The test process used sinusoidal waveform load control, with the test load (maximum load) being 25% of the corresponding mesh breaking strength, the minimum load / maximum load (stress ratio) being 0.1, the loading frequency being 1 Hz, and the number of dynamic fatigue tests being 10000. Figure 2 The ratio of the displacement difference after 10,000 fatigue cycles to the first time the pretension was reached to the effective length of the clamp is used as a characterization method for the dimensional stability of synthetic fiber mesh. The ratio is d = (35.945 - 26.337) / 200 = 0.048.

[0028] Example 3

[0029] UHMWPE mesh with specifications of 1600D / 8 strands - 50 mm, manufactured by Huizhou Yichen Wire Mesh Technology Co., Ltd., was selected. Following the national standard GB / T 4925-2008 "Test Method for Strength and Elongation at Break of Synthetic Fiber Fishing Nets", the synthetic fiber mesh was cut into samples with a width of 4.5 mesh and a length of approximately 30 cm (effective length between clamps was 20 cm). The longitudinal breaking strength of the mesh was tested to be 7330 N. The test process used sinusoidal waveform load control, with the test load (maximum load) being 10% of the corresponding mesh breaking strength, the minimum load / maximum load (stress ratio) being 0.1, the loading frequency being 1 Hz, and the number of dynamic fatigue tests being 10000. Figure 3 The ratio of the displacement difference after 10,000 fatigue cycles to the first time the pretension was reached to the effective length of the clamp is used as a characterization method for the dimensional stability of synthetic fiber mesh. The ratio is d = (33.172 - 30.407) / 200 = 0.014.

[0030] Example 4

[0031] Polyethylene knotted mesh with a wire diameter of 3.5 mm, manufactured by Weihai Hongwei New Material Co., Ltd., was selected. Following the national standard GB / T 4925-2008 "Test Method for Strength and Elongation at Break of Synthetic Fiber Fishing Nets", the synthetic fiber mesh was cut into samples with a width of 4.5 mesh and a length of approximately 30 cm (effective length between clamps: 20 cm). The longitudinal tensile strength of the mesh was tested to be 14607 N. The test process used sinusoidal waveform load control, with the test load (maximum load) being 15% of the corresponding mesh tensile strength, the minimum load / maximum load (stress ratio) being 0.1, the loading frequency being 1 Hz, and the number of dynamic fatigue tests being 10000. Figure 4 The ratio of the displacement difference after 10,000 fatigue cycles to the first time the pretension was reached to the effective length of the clamp is used as a characterization method for the dimensional stability of synthetic fiber mesh. The ratio is d = (42.62 - 21.03) / 200 = 0.108.

[0032] Example 5

[0033] PA knotted netting with specifications of 210D*192-90 mm and a mesh thickness of 3.5 mm, manufactured by Shandong Haoyuntong Netting Technology Co., Ltd., was selected. Following the national standard GB / T 4925-2008 "Test Method for Strength and Elongation at Break of Synthetic Fiber Fishing Nets", the synthetic fiber netting was cut into samples with a width of 4.5 mesh and a length of approximately 30 cm (effective length between clamps: 20 cm). The longitudinal breaking strength of the netting was tested to be 9796 N. The test process used sinusoidal waveform load control, with the test load (maximum load) being 20% ​​of the corresponding netting breaking strength, the minimum load / maximum load (stress ratio) being 0.1, the loading frequency being 1 Hz, and the number of dynamic fatigue tests being 5000. Figure 5 The ratio of the displacement difference after 5000 fatigue cycles to the first time the pretension was reached to the effective length of the clamp is used as a characterization method for the dimensional stability of synthetic fiber mesh. The ratio is d = (14.905 - 11.98) / 200 = 0.015.

[0034] Example 6

[0035] PA knotted netting with specifications of 210D*192-90 mm and a mesh thickness of 3.5 mm, manufactured by Shandong Haoyuntong Netting Technology Co., Ltd., was selected. Following the national standard GB / T 4925-2008 "Test Method for Strength and Elongation at Break of Synthetic Fiber Fishing Nets", the synthetic fiber netting was cut into samples with a width of 4.5 mesh and a length of approximately 30 cm (effective length between clamps was 20 cm). The longitudinal breaking strength of the netting was tested to be 9796 N. The test process used sinusoidal waveform load control, with the test load (maximum load) being 40% of the corresponding netting breaking strength, the minimum load / maximum load (stress ratio) being 0.1, the loading frequency being 1 Hz, and the number of dynamic fatigue tests being 5000. Figure 6 The ratio of the displacement difference after 5000 fatigue cycles to the first time the pretension was reached to the effective length of the clamp is used as a characterization method for the dimensional stability of synthetic fiber mesh. The ratio is d = (13.386 + 16.33) / 200 = 0.148.

[0036] Example 7

[0037] PA knotted netting with specifications of 210D*192-90 mm and a mesh thickness of 3.5 mm, manufactured by Shandong Haoyuntong Netting Technology Co., Ltd., was selected. Following the national standard GB / T 4925-2008 "Test Method for Strength and Elongation at Break of Synthetic Fiber Fishing Nets", the synthetic fiber netting was cut into samples with a width of 4.5 mesh and a length of approximately 30 cm (effective length between clamps was 20 cm). The longitudinal breaking strength of the netting was tested to be 9796 N. The test process used sinusoidal waveform load control, with the test load (maximum load) being 50% of the corresponding netting breaking strength, the minimum load / maximum load (stress ratio) being 0.1, the loading frequency being 1 Hz, and the number of dynamic fatigue tests being 1000. Figure 7 The ratio of the displacement difference after 1000 fatigue cycles to the first time the pretension was reached to the effective length of the clamp is used as a characterization method for the dimensional stability of synthetic fiber mesh. The ratio is d = (11.901 + 18.619) / 200 = 0.153.

[0038] By comparing the above implementation examples, we found that the dimensional stability of synthetic fiber mesh is closely related to the material, knot type, stress conditions, and fatigue cycles. Therefore, the technical method involved in this invention can quantitatively characterize the dimensional stability of synthetic fiber mesh.

[0039] The undescribed parts of this invention are the same as or implemented using existing technology. The applicant declares that this invention is illustrated through the above embodiments, but the invention is not limited to the above detailed methods, i.e., it does not mean that the invention must rely on the above detailed methods to be implemented. Those skilled in the art should understand that any improvements to this invention, equivalent substitutions of raw materials for the product of this invention, additions of auxiliary components, and selection of specific methods all fall within the protection and disclosure scope of this invention.

Claims

1. A quantitative characterization method for the dimensional stability of synthetic fiber mesh, characterized in that, The synthetic fiber mesh to be tested was cut into samples of a certain size and subjected to dynamic fatigue testing in tensile mode. The ratio of the displacement difference after a certain number of fatigue cycles to the effective length of the clamp is used as the standard for evaluating the dimensional stability of synthetic fiber mesh.

2. The quantitative characterization method for the dimensional stability of synthetic fiber mesh according to claim 1, characterized in that: in, The sample is prepared as follows: the synthetic fiber mesh is cut into 4.5 mesh widths, ensuring that the effective length between the clamps is 20 cm.

3. The quantitative characterization method for the dimensional stability of synthetic fiber mesh according to claim 1, characterized in that: in, The synthetic fiber mesh is selected from polyethylene mesh, polyamide multifilament mesh, polyamide monofilament mesh or ultra-high molecular weight polyethylene mesh.

4. The quantitative characterization method for the dimensional stability of synthetic fiber mesh according to claim 1, characterized in that: in, The dynamic fatigue test was conducted using a fatigue testing machine.

5. The quantitative characterization method for the dimensional stability of synthetic fiber mesh according to claim 4, characterized in that: in, The test process adopted sinusoidal waveform load control. The maximum load was 10% to 80% of the corresponding mesh breaking strength, the ratio of minimum load to maximum load was 0.1, and the loading frequency was 1 to 10 Hz.

6. The quantitative characterization method for the dimensional stability of synthetic fiber mesh according to claim 1, characterized in that: in, The method for determining the pretension of the mesh sample is as follows: referring to the provisions of GB / T 6965-2004, the pretension value of each eyelet, warp or weft thread is equal to the self-weight of 250m of mesh length.

7. The quantitative characterization method for the dimensional stability of synthetic fiber mesh according to claim 1, characterized in that: in, The number of dynamic fatigue tests is 1,000 to 100,000.

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