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Brief introduction of the basic performance of O-ring (1)

Update:2019-12-20
Summary:
O-ring is a synthetic rubber seal made by copolymerizing butadiene and acrylonitrile. It is a synthetic rubber with good oil resistance (especially nitrile rubber alkane oil) and good aging resistance. There are five types of acrylonitrile content (%) in the nitrile rubber: 42-46, 36-41, 31-35, 25-30, and 18-24. The more acrylonitrile content, the better the oil resistance, but the cold resistance decreases accordingly. It can be used for a long time in air at 120 ° C or in oil at 150 ° C. In addition, it also has good water resistance, air tightness and excellent adhesion properties. The hardness of the silicone O-ring is mainly related to the amount of filler and the crosslinking density of the rubber. If it is simply reinforced with white carbon, under the same conditions of use, the relationship between hardness and service life will first rise and then decrease, and become parabolic. The use hardness of silicone rubber is 40-60 degrees. The lower the hardness, the incomplete reinforcement, the poor the comprehensive performance, the higher the hardness, the larger the amount of silica added, the damage to the structure of the silicone rubber itself, and the poor overall performance. Crosslinking density generally has a small effect on hardness. Most of the silicone rubbers generally used are vulcanized. Compared with fully vulcanized silicone rubbers, the hardness is definitely smaller, and the service life is much smaller than that of fully vulcanized silicone rubber. The abrasion resistance of silicone rubber products is generally reflected in the ability of the surface of silicone products to be easily damaged. Good silicone products generally rarely rub off the surface of the product due to external factors, and do not affect the appearance, text, and color of the performance. Qualified silicone pacifiers must be non-toxic, odorless and transparent, using 100% food-grade (imported) silicone materials; very soft and extremely flexible, nipples can be extended to 5mm in length, so that the baby's tongue can be as if it is sucking breast milk O-shaped sealing ring mouth uses ultra-soft silicone, which is twice as thick as a normal pacifier, so the baby will not break during the sucking process, and it will not be damaged when it is resistant to long-term biting. Generally qualified silicone Most of them are produced by automatic machinery. The production process is fully automatic without human intervention to ensure the most safe and environmentally friendly design and touch. It makes the baby feel like sucking breast milk during the sucking process. Silicone products have production molds, why should we open sample molds? First of all, sometimes when the size and structure of the silicone products sent by customers are not very accurate or completely determined, we usually use sample molds for development, which will facilitate the modification of the size and structure of the silicone products later. In addition, sometimes when the customer requires mold opening but there is no drawing file, then we can only perform proofing (sample opening), use the sample to measure the product structure and size data, and use the data measured by the sample data to re-draw, and Opening the mold, but the data obtained through data measurement may generally have errors. Only by opening the mold with the sample can the reduction of the number of modifications of the production mold be guaranteed. Silicone O-ring has excellent heat resistance, cold resistance, ozone resistance, atmospheric aging resistance, and good insulation properties, but the tensile strength is worse than ordinary rubber and does not have oil resistance. Suitable for household appliances such as electric water heaters, irons, microwave ovens, etc. It is also suitable for a variety of supplies that come into contact with the human body, such as kettles, water dispensers, etc. Not recommended for most concentrated solvents, oils, concentrated acids and sodium hydroxide. The general temperature range is -55 ~ 250 ℃. The biggest feature is that it has both oil resistance and heat resistance. Zh An O-ring is a rubber ring with a circular cross-section. Because its cross-section is an O-shape, it is called an O-ring. One of the most widely used hydraulic and pneumatic transmission systems. O-rings are generally circular rubber seals with a circular cross section. Under static conditions, O-rings prevent leakage of liquid and gaseous media. Under dynamic conditions, O-rings can also be used as dynamic sealing elements for axial reciprocating motion and low-speed rotary motion. According to different conditions, different materials can be selected to suit them. But the service life is much shorter than fully cured. It is widely used in the production of various oil-resistant rubber products, a variety of oil-resistant gaskets, gaskets, sleeves, flexible packaging, soft hoses, printing and dyeing rubber rollers, cable adhesive materials, etc., and has become essential in the automotive, aviation, petroleum, copying and other industries Elastic material.