EVA material introduction
EVA, the full name of which is ethylene-vinyl acetate copolymer, is a general-purpose polymer resin with good flexibility, elasticity, impact resistance and waterproofness. The vinyl acetate polar groups contained in its molecular chain make it have excellent bonding properties, and by changing the content of vinyl acetate, the performance of the material can be adjusted to meet the needs of different application scenarios.
Test method for waterproof performance of EVA fishing gear bag
Hydrostatic pressure test method
Principle: Place the EVA fishing gear bag sample in a hydrostatic pressure tester, and apply a hydrostatic pressure that gradually increases at a certain rate to one side of the sample until water droplets seep out of the other side. Record the water pressure value at this time, which is the hydrostatic pressure resistance value of the sample, usually in millimeters of water column (mmH₂O). Generally speaking, the higher the hydrostatic pressure resistance value, the better the waterproof performance of the EVA fishing gear bag.
Operation steps: First, prepare the test equipment, ensure that the hydrostatic pressure tester used works normally, and calibrate to the standard state. Prepare distilled or deionized water and ensure that its temperature is controlled within the specified range, such as 21±2℃. Then take at least 3 representative test samples along the diagonal direction of the width of the EVA fishing tackle bag, and the size of each sample is at least 200×200mm. Clamp the sample on the tester to ensure that the sample is in contact with the water surface and that water does not penetrate the sample before the test. Then apply a continuously increasing water pressure to the sample at a certain rising rate, such as 6.0±0.3kpa/min (60±3cmH₂O/min), and observe the water seepage phenomenon. Record the hydrostatic pressure value when the third water droplet just appears on the sample, and ignore the water droplet within 3mm of the edge of the adjacent clamp. If the penetrating water droplet appears at the edge of the clamping position and the hydrostatic pressure value is lower than the lowest value of the hydrostatic pressure of other samples of the same type, then eliminate this data and add additional samples for separate testing. Finally, express the hydrostatic pressure value and its average value of each sample in kPa (cmH₂O), retaining one decimal place.
Dynamic water pressure test method
Principle: Apply a water pressure P that increases at a constant rate on one side of the sample until the other side is penetrated by water and a certain number of water droplets appear. The applied water pressure P is the waterproof performance index of the sample. This method is more suitable for coated fabrics or fabrics with tight structures. It can more realistically simulate the situation of constantly changing water pressure in actual use, so as to more accurately evaluate the waterproof performance of EVA fishing gear bags under dynamic conditions.
Operation steps: Prepare a dynamic water pressure tester and distilled or deionized water that meet the requirements. Cut a sample of suitable size from the EVA fishing gear bag, generally round or square, to ensure that the sample is not damaged or wrinkled. Install the sample on the clamping device of the tester to ensure that the sample is flat and well sealed to prevent water from leaking from the edge of the sample. Start the tester, gradually increase the water pressure according to the set water pressure rise rate, and observe the water seepage on the other side of the sample. Record the water pressure value when the water droplets appear. Usually, the water pressure when the third droplet appears is used as the test result. Repeat the test several times and take the average value to evaluate the waterproof performance of the EVA fishing gear bag.
Spray test method
Principle: By continuously spraying or dripping water on the EVA fishing gear bag sample, observe the water stain characteristics on the surface of the sample after a certain period of time, and compare it with standard samples of various wetness degrees to evaluate its waterproofness. This method mainly evaluates the water repellency of the surface in situations such as rainfall and splashing that may be encountered during the use of the product.
Operation steps: First prepare the spray test device, including the nozzle, water tank, water pump, pressure regulating device, etc., to ensure that the spray of the nozzle is uniform and meets the spray intensity and angle required by the standard. Then take an appropriate amount of representative samples from the fishing gear bag and fix them on the specified test bench to ensure that the samples are flat, wrinkle-free and firmly fixed. Turn on the spray device and spray the sample according to the set spray time, water volume and angle. The general spray time is about 25-30 seconds. After the spraying is finished, the sample is compared with the standard rating chart. The waterproof performance of the EVA fishing bag is rated according to the water stains, water droplet distribution and wetting degree on the sample surface. The grades are usually divided into 5 levels, with 5 being the best and 1 being the worst.
Immersion test method
Principle: The EVA fishing bag sample is completely immersed in water. After a certain period of time, observe whether water has penetrated into the sample. If there is no water mark inside the sample, it indicates that it has good waterproof performance; otherwise, the waterproof performance is poor. This method is relatively simple to operate and can intuitively judge the waterproof effect of the EVA fishing bag, but it cannot accurately quantify its waterproof degree.
Operation steps: Choose a suitable container, ensure that its size can fully accommodate the EVA fishing bag sample, and the water level in the container is high enough to completely immerse the sample. Add a certain amount of distilled water or deionized water to the container and record the initial volume or liquid level of the water. Carefully place the EVA fishing bag sample in the container, making sure that the sample is completely submerged in water, and avoid the sample from being too tightly in contact with the container wall or bottom to affect water penetration. To prevent the sample from floating up, you can use an appropriate weight to press it underwater. Then place the container under specified environmental conditions, such as a specific temperature and humidity, and let it stand for a period of time, usually 24 hours or longer, depending on the specific test standard. After the standing time is over, take out the sample and observe whether there are signs of water infiltration inside it, such as whether there are water droplets, whether it is damp, etc., and record the observation results.
Underwater pressure test method
Principle: Place the EVA fishing bag underwater and apply a certain gas pressure or liquid pressure to it to form a pressure difference between the inside and outside, and observe whether the sample seeps water under the action of the pressure difference. This method can simulate the external water pressure that the fishing bag is subjected to underwater in actual use, and at the same time, by controlling the pressure size and action time, more accurately evaluate its waterproof performance, especially for fishing bag products that need to withstand higher water pressure.
Operation steps: Prepare underwater pressurization test equipment, including pressure vessel, pressurization equipment, pressure sensor, data acquisition system, etc. Ensure that the pressure vessel can provide sufficient water depth to simulate the water pressure in actual use, and the pressure sensor and data acquisition system in the container can accurately measure and record pressure changes. Place the EVA fishing gear bag sample in the pressure vessel, ensure that the sample is completely submerged in water, and leave enough space between the sample and the inner wall of the container to avoid affecting the uniform distribution of pressure. Apply a set pressure to the inside of the pressure vessel through the pressurization equipment and maintain it for a certain period of time, while observing whether there are bubbles escaping or other signs of water seepage on the surface of the sample. If the sample seeps water, record the pressure value and time point at this time; if the sample does not seep water within the specified pressure and time range, it is considered to meet the waterproof requirements. After the test, slowly release the pressure and take out the sample for further inspection and recording.
Factors affecting the waterproof performance of EVA fishing gear bag
Material quality: High-quality EVA material has a tighter molecular structure and more uniform material, and its waterproof performance is relatively good. If there are impurities, pores or incomplete molecular chains in the material, its waterproof performance will be reduced.
Production process: The production process, such as foaming process, molding process, etc., has an important impact on the waterproof performance of EVA fishing tackle bags. For example, uneven foaming may cause gaps inside the material, thus affecting the waterproof effect.
Sealing design: The sealing design of the zipper, interface and other parts of the fishing tackle bag is crucial. If these parts are not sealed well, water will penetrate from the gaps. Even if the EVA material itself has good waterproof performance, the waterproof performance of the entire fishing tackle bag will be greatly reduced.
Use environment: In harsh environments, such as long-term immersion in water, external force extrusion, contact with chemicals, etc., the waterproof performance of the EVA fishing tackle bag may be affected. Therefore, in actual use, the appropriate fishing tackle bag should be selected according to the specific environmental conditions, and attention should be paid to the correct use and maintenance methods to extend its service life and maintain good waterproof performance.
Waterproof performance test standards and certification
AATCC 127 standard: AATCC 127 is a waterproof and breathable product test standard developed by the American Textile Chemists and the Color Fastness Association. It is widely used in waterproof clothing, tents, rain gear and outdoor equipment. The test principle is to subject one side of the sample to the effect of hydrostatic pressure increasing at a certain rate until water droplets seep out from three places on the surface of the sample, and measure the water pressure value at this time. If the EVA fishing gear bag meets this standard, it means that it has good waterproof performance when facing a certain water pressure, and can meet the basic waterproof needs in daily fishing and other activities.
ISO 811 standard: ISO 811 is a standard for the determination of textile hydrostatic pressure resistance issued by the International Organization for Standardization. It is applicable to a variety of waterproof materials, including outdoor clothing, military equipment and functional home textiles. Its test method is similar to AATCC 127, but the test conditions and requirements may be slightly different, such as the requirements for water temperature and water pressure rise rate. The waterproof performance of EVA fishing gear bags certified by this standard is highly recognized in the international market, which is conducive to the export and promotion of products.
GB/T 4744 standard: GB/T 4744 is a Chinese national standard, which is mainly aimed at the waterproof fabric testing needs of the Chinese market, covering waterproof clothing, outdoor tents, car interiors and other fields. This standard is slightly different from ISO 811 in specific processes and test conditions, but is generally consistent with it. EVA fishing gear bags that meet the GB/T 4744 standard indicate that their waterproof performance meets the requirements of relevant domestic standards and can adapt to the use environment and quality supervision requirements of the domestic market.
Summary
The waterproof performance of EVA fishing gear bags is one of its key indicators, which is directly related to the practicality and reliability of the product. Through in-depth research on EVA materials and the use of appropriate waterproof performance test methods, such as hydrostatic pressure test, dynamic water pressure test, spray test, immersion test and underwater pressure test, its waterproof performance can be comprehensively and accurately evaluated. At the same time, understanding the factors that affect waterproof performance, such as material quality, production process, sealing design and use environment, and complying with relevant testing standards and certification requirements are of great significance to improving the waterproof performance and market competitiveness of EVA fishing bags. In actual production and use, various factors should be considered comprehensively, and appropriate testing methods and standards should be selected to ensure that EVA fishing bags can maintain good waterproof effects in various complex environments and meet the needs of fishing enthusiasts.
Post time: Jun-11-2025