Small, lightweight pneumatic fenders

Abstract

By resolving the issue of air leakage during vulcanization and achieving weight reduction, the requirements for naval vessels are met. [Solution] The present invention relates to a small, lightweight pneumatic fender produced by a vulcanization process that involves adjusting the distance between the vulcanization mold and the fender.

Description

Technical Field

[0001] The present invention relates to a small and lightweight pneumatic fender for application to ships that require mobility, speed, and agility.

Background Art

[0002] The pneumatic fender was devised to overcome the limitations of general rubber fenders. It is a structure in the form of an airbag filled with air inside, with excellent shock absorption, no need for special internal materials, and being economically superior. Such a pneumatic fender is installed on the side of a quay or dock related to a ship. When the ship approaches or moors at the dock, the impact between the dock and the ship is buffered by the air pressure of the pneumatic fender, preventing damage to the dock and the ship.

[0003] On the other hand, as disclosed in Patent Document 1, the pneumatic fender cannot be made with a casting form for the skin at once, but is made by pasting a plurality of pieces. Therefore, the materials of the skin overlap, resulting in increased thickness, excessive weight, and relatively high process costs. When applied to naval ships, the weight becomes excessively heavy, making it difficult to meet the levels required by naval ships for conditions such as mobility, speed, and strategic agility. When lightweighting, there is a problem of air leakage occurring during the vulcanization process due to the reduced thickness of the inner and outer rubber.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The objective of the present invention is to solve the above-mentioned problems, and to provide a small, lightweight pneumatic fender that can meet the requirements of naval vessels by solving the problem of air leakage during vulcanization caused by the thinning of the inner and outer rubber surfaces for weight reduction through the vulcanization process by adjusting the gap between the vulcanization mold and the fender. [Means for solving the problem]

[0006] To achieve the above objective, a small, lightweight pneumatic fender according to one embodiment of the present invention is manufactured by a vulcanization process that involves adjusting the distance between the vulcanization mold and the fender.

[0007] Here, the above interval is the interval before vulcanization and may be 30% to 80% of the fender thickness.

[0008] Furthermore, the size of the fender may be in the range of 500 mm to 800 mm in diameter and 1,000 mm to 1,200 mm in length.

[0009] On the other hand, the fender includes an air-filled section into which air is filled, an inner rubber layer provided to enclose the air-filled section, a reinforcing layer provided on one surface of the inner rubber layer, and an outer rubber layer formed on one surface of the reinforcing layer, and the total thickness of the inner rubber layer and the outer rubber layer may be 7 mm or less. [Effects of the Invention]

[0010] According to one embodiment of the present invention, a small, lightweight pneumatic fender can be made lighter by solving the problem of air leakage during vulcanization through a vulcanization process that involves adjusting the distance between the vulcanization mold and the fender, thereby meeting the requirements of naval vessels.

[0011] Furthermore, small, lightweight pneumatic fenders can reduce not only thickness and weight by optimizing the overlap of the inner and outer rubber layers, but also costs. [Brief explanation of the drawing]

[0012] [Figure 1] This photograph shows the spacing between the vulcanization mold and the fender during the vulcanization process. [Figure 2] This is a schematic diagram showing the spacing between the vulcanization mold and the fender during the vulcanization process. [Figure 3] This is a cross-sectional view showing a small, lightweight pneumatic fender according to the present invention. [Figure 4] This is a schematic diagram showing a cross-section of A in one embodiment of Figure 3. [Figure 5] This is a manufacturing process diagram illustrating the manufacturing method of the small, lightweight pneumatic fender according to Example 1 and Example 2. [Figure 6] This is a photograph showing the weight of Example 1. [Figure 7] This is a photograph showing the results from Experimental Example 1. [Figure 8] This is a photograph showing the results from Experimental Example 1. [Modes for carrying out the invention]

[0013] The embodiments of the present invention will be described in detail below. However, the present invention is not limited to the embodiments disclosed below and can be realized in a variety of different forms, and these embodiments are provided merely to further fully explain the contents of the present invention to a person of ordinary skill, so as to make the disclosure of the present invention complete.

[0014] In this specification, when one element is referred to as being located "above" or "below" another element, this includes all meanings, including that the aforementioned element is located directly "above" or directly "below" the other element, or that additional elements may be interposed between these elements. In this specification, the terms "upper" and "lower" are relative concepts set from the observer's perspective, and if the observer's perspective changes, "upper" may mean "lower" or "lower" may mean "upper".

[0015] In multiple drawings, the same reference numerals denote substantially identical elements to each other. Also, terms such as "comprising" or "having" are intended to specify the presence of the described features, numbers, steps, operations, components, parts, or combinations thereof, and should not be construed as precluding the presence or addition of one or more different features, numbers, steps, operations, components, parts, or combinations thereof.

[0016] In describing embodiments of the present invention, the terms are terms defined in consideration of the functions in the embodiments of the present invention, which may vary depending on the intention or convention of the user, operator, etc. Therefore, the definition should be determined based on the content throughout the present invention.

[0017] Conventionally, due to the thickness of the rubber on the inner and outer surfaces being reduced to lighten the fender, air leakage frequently occurred during the vulcanization process. In the present invention, by adjusting the gap G between the vulcanization mold 1 and the fender 100, the problem of frequent air leakage in the vulcanization process has been solved.

[0018] Hereinafter, the small and lightweight pneumatic fender of the present invention will be described in detail with reference to the drawings.

[0019] The size of the small and lightweight pneumatic fender 100 according to the present invention satisfies the range where the diameter D is from 500 mm to 800 mm and the length L is from 1,000 mm to 1,200 mm, and it may be manufactured by a vulcanization process by adjusting the gap G between the vulcanization mold 1 and the fender 100. Here, the gap G may be different before and after vulcanization. FIGS. 1 and 2 show the gap G before vulcanization when inflation has not occurred. In this embodiment, the thickness of the fender 100 is designed to be 11 mm or less, and the gap G before vulcanization may be from 30% to 80% of the thickness of the fender 100. In this case, the inflation rate during vulcanization can be adjusted to 1% to 2% or less. When the gap G before vulcanization is adjusted to the above-mentioned range, it is possible to prevent the inflation rate during vulcanization from exceeding 2% and becoming large, and the problem of air leakage can be solved.

[0020] On the one hand, the distance G between the vulcanization mold 1 and the fender 100 can be adjusted by changing the diameter of the molding die. When the diameter of the molding die increases, the distance G between the vulcanization mold 1 and the fender 100 can become smaller. In this embodiment, the diameter of the molding die was enlarged and applied compared to the prior art, and the expansion rate during vulcanization was adjusted to 2% or less.

[0021] Referring to FIGS. 3 and 4, the small lightweight pneumatic fender 100 may include an air filling portion 110, an inner rubber layer 120, a reinforcing layer 130, and an outer rubber layer 140.

[0022] The air filling portion 110 is a region filled with air, and it is desirable to maintain the internal pressure within the range of 50 kPa to 80 kPa so that it can buffer the impact between the quay and the ship when the ship approaches or moors at the quay. By providing the air filling portion 110, the impact absorption ability is excellent compared to conventional fenders, and internal materials may not be required and it can be economical.

[0023] The inner rubber layer 120 is provided to wrap the air filling portion 110 and may be made of a material having elasticity together with the outer rubber layer 140 described later. The inner rubber layer 120 and the outer rubber layer 140 may be made of the same material, but may be made of different materials depending on the applied products or as necessary. For example, one or more selected from polyethylene (PE), polypropylene (PP), rubber (Natural Rubber, NR), butadiene rubber (Butadiene Rubber, BR), styrene butadiene rubber (Stylrene Butadiene Rubber, SBR), acrylonitrile butadiene rubber (Acrylonitrile Butadiene Rubber, NBR), fluoro rubber, silicone rubber (Silicone Rubber, VMQ), chloroprene rubber (Chloroprene Rubber, CR), ethylene propylene diene rubber (Ethylene Propylene Diene Rubber, EPDM), and butyl rubber (Isobutylene Isoprene Rubber, IIR) may be used.

[0024] In this embodiment, the thickness of the inner rubber layer 120, which is relatively less susceptible to impact from external pressure, may be 0.5 to 1 times the thickness of the outer rubber layer 140, and the color of the inner rubber layer 120 is not particularly limited, but may be black, for example.

[0025] On the other hand, the combined thickness of the inner rubber layer 120 and the outer rubber layer 140 may be 7 mm or less. As described above, optimizing the overlap of the inner rubber layer 120 and the outer rubber layer 140 can reduce not only weight and thickness but also costs. Furthermore, it can meet the maneuverability, speed, and agility requirements of naval vessels.

[0026] The reinforcing layer 130 is provided on one surface of the inner rubber layer 120 and may be formed as at least one or more layers. For example, if it is formed as multiple layers, each layer may be made of the same material. For example, nylon fiber can be used as the material for the reinforcing layer 130 to reduce weight while maintaining high durability. In this embodiment, nylon fiber may refer to a polyamide-based synthetic polymer compound.

[0027] The outer rubber layer 140 is provided on one side of the reinforcing layer 130 and, being located on the outermost surface, is designed to easily absorb external impacts while being preferably thicker than the inner rubber layer 120 to reduce the risk of breakage. For example, the thickness of the outer rubber layer 140 may be one to two times the thickness of the inner rubber layer 120. If the thickness is outside the above range, it may be easily damaged by external impacts, and if damage occurs, the entire small, lightweight pneumatic fender 100 will need to be replaced, which is not only costly but may also make it difficult to achieve the weight reduction that is the main objective of this embodiment.

[0028] On the other hand, the outer rubber layer 140 may be gray so that it can be applied to vessels whose primary purpose is to conduct combat. As described above, the usable materials may include ethylene propylene diene rubber (EPDM), carbon black, processing oil, and gray pigment. The carbon black included here is present in trace amounts and does not affect the properties of the outer rubber layer 140, and also prevents contamination of the hull during docking. When composed of the components mentioned above, it has excellent oxidation resistance, ozone resistance, and corrosion resistance, so that the small, lightweight pneumatic fender 100 can be prevented from deteriorating when exposed to the seawater surface or damaged by natural factors such as salt, and can maintain its original color without significant change.

[0029] The present invention will be described in more detail below with reference to examples. These examples are solely for the purpose of illustrating the present invention in more detail, and it will be obvious to those who are ordinarily skilled in the art that the scope of the present invention is not limited thereto.

[0030] <Examples 1 and 2: Manufacturing of small, lightweight pneumatic fenders> As shown in Figure 5, the gap between the mandrels, which are the molding dies, was set so that the expansion rate during vulcanization was adjusted to a range of 1% to 2% or less. Then, the inner rubber layer, reinforcing layer, and outer rubber layer were molded and separated from the mandrels. The inner rubber layer and reinforcing layer were then laminated and set so that the molded parts separated from the mandrels overlapped each other, and joint molding was performed. After inserting air to the extent that it maintained its shape, the outer rubber layer was molded to produce the fender. After inserting the fender into the vulcanization die and assembling it, air was filled into the inside of the fender through an air valve, and vulcanization was carried out to produce a small, lightweight, pneumatic fender with the weight shown in Figure 6.

[0031] JPEG2026099742000002.jpg54170

[0032] <Comparative Examples 1 and 2: Manufacturing of small, lightweight pneumatic fenders> A small, lightweight pneumatic fender was manufactured using the same method as in Examples 1 and 2, except that the gap between the mandrels, which are the molding dies, was set so that the expansion rate during vulcanization was adjusted to a range of 3% or more.

[0033] JPEG2026099742000003.jpg54170

[0034] (Experimental Example 1: Performance Test) The small, lightweight pneumatic fenders according to Example 1 and Example 2 were subjected to performance tests for air leakage and hydrostatic pressure using the method of the international standard ISO 17357-1:2014. The results are shown in Figures 7 and 8, and Tables 3 and 4.

[0035] Referring to Figure 7, in both Examples 1 and 2, it was confirmed that the morphology was good after air filling. Furthermore, as disclosed in Table 3, it was confirmed that the changes in diameter and length were within the acceptable range under the condition of an internal pressure of 80 kPa after air filling, and no air leakage was detected after observation for 30 minutes.

[0036] Referring to Table 4, in Examples 1 and 2, a hydrostatic pressure test was performed at a pressure of 250 kPa for 10 minutes, and it was confirmed that the change in length was within 10%, which is within the acceptable error range.

[0037] On the other hand, in the case of Comparative Example 1 and Comparative Example 2, as illustrated in Figure 8, air leakage occurred during the vulcanization process after air filling, making it impossible to proceed with further experiments.

[0038] JPEG2026099742000004.jpg92170

[0039] JPEG2026099742000005.jpg121170

[0040] As explained above, the specific description of the present invention has been given by examples with reference to the attached drawings. However, since the above-described examples merely illustrate desirable examples of the present invention, the present invention should not be understood as being limited to the above examples, and the scope of the present invention should be understood as the claims and equivalents described later. For example, the drawings are schematic representations mainly of each component to aid understanding, and the thickness, length, number, etc. of each component shown may differ from the actual dimensions due to the convenience of drawing creation. Furthermore, the material, shape, dimensions, etc. of each component shown in the above embodiments are just examples and are not particularly limiting, and various modifications are possible as long as they do not substantially exceed the effects of the present invention. [Explanation of symbols]

[0041] 1 Vulcanization mold 100 Small, lightweight pneumatic fenders, fenders 110 Air filling section 120 Inner rubber layer 130 Reinforcement layer 140 Outer rubber layer

Claims

1. Manufactured by a vulcanization process involving adjustment of the gap between the vulcanization mold and the fender. Lightweight pneumatic fender.

2. The aforementioned interval is the interval before vulcanization and is 30% to 80% of the thickness of the fender. The lightweight pneumatic fender according to claim 1.

3. The aforementioned fender material is, An air filling section where air is filled, An inner rubber layer is provided so as to enclose the air-filled section, A reinforcing layer is provided on one surface of the inner rubber layer, An outer rubber layer formed on one surface of the reinforcing layer, Includes, The sum of the thicknesses of the inner rubber layer and the outer rubber layer is 7 mm or less. The lightweight pneumatic fender according to claim 1.

4. The internal pressure of the air-filled section is between 50 kPa and 80 kPa. The lightweight pneumatic fender according to claim 3.

5. The thickness of the inner rubber layer is 0.5 to 1 times the thickness of the outer rubber layer. The lightweight pneumatic fender according to claim 3.

6. The reinforcing layer comprises at least one layer, The aforementioned at least one layer is made of the same material. The lightweight pneumatic fender according to claim 3.

7. The aforementioned material is nylon fiber. The lightweight pneumatic fender according to claim 6.

8. The size of the fender is such that the diameter is between 500 mm and 800 mm and the length is between 1,000 mm and 1,200 mm. The lightweight pneumatic fender according to claim 1.

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