A method for detecting the failure of a rubber sealing ring

Abstract

The invention provides a failure detection method for rubber seal rings. The method comprises steps as follows: residual compression permanent deformation rates of multiple rubber seal rings are calculated by stress loading and aging tests; surface crosslinking density and surface oxygen relative atom content of each rubber seal ring after the aging tests are measured, a regression analysis prediction equation of the residual compression permanent deformation rates of the rubber seal rings is established, a thin sheet is cut out from the surface of each rubber seal ring after storage for a period of time T with ammunition, surface crosslinking density X1 and surface oxygen relative atom content X2 of the thin sheet are measured, data obtained through measurement is substituted into the regression analysis prediction equation, the residual compression permanent deformation rate of each rubber seal ring after storage for a period of time T with ammunition is solved, and a detection result is obtained through combination with a designed failure critical value. With adoption of the detection method, the rubber seal rings are not required to be dismounted from an ammunition product, sothat nondestructive detection of the rubber seal rings which are stored with the ammunition for a long time is realized, besides, the detection result is accurate and reliable, and the operating process is simple and fast.

Description

Technical field [0001] The invention relates to a rubber sealing ring stored with ammunition for a long time, in particular to a failure detection method of the rubber sealing ring. Background technique [0002] Commonly used rubber seals include silicone rubber seals, fluorine rubber seals, natural rubber seals and nitrile rubber seals. These rubber seals have good sealing performance and are widely used in various ammunition storage structures. Due to the weaknesses in the molecular structure of rubber itself, during long-term storage with ammunition, rubber seals are extremely susceptible to mechanical stress, oxygen in the medium and the air, temperature, and humidity. Macroscopically, the rubber sealing ring produces cumulative permanent deformation, which causes its compression ratio to decrease, causing leakage and loss of sealing performance. It is a key material and weak link that affects the storage life of ammunition products. Therefore, it is extremely necessary to r...

AI Technical Summary

Problems solved by technology

[0004] The Arrhenius model extrapolation method has the advantage of being fast, but because the apparent activation energy in the Arrhenius model has certain assumptions, that is, the 3-4 test temperatures used in the accelerated aging test and the extrapolation The activation energy under the condition of storage temperature remains unchanged, that is, the activation energy is a constant independent of temperature, but this is different from the actual situation. First, when the difference between the test temperature and the storage temperature is large, the accelerated aging mechanism It may be inconsistent with the actual storage aging mechanism, and the apparent activation energy will change during the accelerated aging process. Second, a large number of literatures have reported the non-Arrhenius behavior of rubber sealing rings in the aging degradation process, that is, in the aging degradation process. The apparent activation energy changes during the process, so these conditions will lead to inaccurate storage life at room temperature obtained by high-temperature accelerated aging extrapolation

In addition, using 3-4 temperature point aging tests also requires a lot of time, material resources, and manpower

Although the measurement of the compression set by removing the rubber sealing ring has the characteristics of high accuracy, because the ammunition is a "long-term storage, one-time use" product, it is easy to cause waste of ammunition, the cost of disassembly is too high, and the actual operability is extremely low.

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