An important factor in rubber O-rings is the use of temperature. High temperature will accelerate the aging of plastic materials. The larger the operating temperature, the larger the permanent deformation of O-ring contraction. When the permanent deformation exceeds 40%, the O-ring loses its sealing, resulting in leakage. Due to shrinkage deformation, the initial stress value formed in the O-ring rubber information will gradually land and dissipate with the aerodynamic flow and temperature landing of the O-ring.
Because of the dramatic drop in temperature, the original contraction of the O-ring operating below zero may be reduced or completely dissipated. O Generally use sealing rings, try to choose a large section of the O-ring. The volume of O-ring squeezed into the void should be less than its maximum value on the same premise. Silicone sealing ring is a good moisture-proof agent, adsorbent and catalyst carrier, made of perforated material, can absorb a variety of substances. The absorption of silica gel is generally physical adsorption and can be reused. In partial alkali metal silicate (such as sodium silicate) solution to add acid, acidification, and then pour a certain amount of electrolyte mixed, made of silicate abnormal glue; Or in the concentrated sodium silicate solution to add acid or ammonium salt, will also bring silicate glue. Under the condition of -50~-60℃, the plastic material which is not resistant to low temperature will completely lose the initial stress. Even low temperature resistant plastic materials, the initial stress will not exceed 20℃ initial stress 25%. Because the original torsion of the O-ring depends on the expansion coefficient. Therefore, when selecting the original compaction amount, it is necessary to ensure that there is still sufficient sealing capacity after the stress landing caused by temperature landing in the process of stress landing. When working below zero, special attention should be paid to the repair index and deformation index of plastic materials.
Generally speaking, in the design, the O-ring should try to keep the right working temperature, or choose high and low temperature O-ring materials, in order to improve the service life. Silicone products with silicone as the main raw material are called silicone products. Silica gel is a porous porous structure of varying sizes, made from silicic acid abnormal glue. It is a good moisture-proof agent with an open porous structure that can absorb a variety of substances, adsorbents and catalyst carriers.
FOREVER SEALS can provide various types of seals.
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