乙丙橡胶密封圈在压缩状态下的使用寿命预测

摘要

采用热空气加速老化,研究乙丙橡胶密封圈(简称EPR,下同)的压缩永久变形率随老化时间的变化.将老化前后样品的红外光谱分析,发现EPR的老化主要是热氧引起的分子断裂造成的;利用阿累尼乌斯方程和线性回归估计分析,预测乙丙橡胶密封圈在受压状态下的使用寿命.以压缩永久变形率作为评价项目,建立乙丙橡胶环境温度下使用寿命预测方程,推测出在95%的置信水平下,乙丙橡胶密封圈的压缩密封寿命为14.8年.%Accelerated aging by hot air was used to study the change of compression set with the aging time of the EPR. The infrared spectra of samples before and after aging were analyzed. It was found that the aging of EPR was mainly caused by the thermal oxygen induced molecular rupture and cross-linking. Using the Arrhenius equa-tion and regression analysis,the service life of EPR seals under pressure is predicted. Taking the compression set as the test item,the prediction equation of service life of ethylene-propylene rubber seals at ambient temperature was established. It was presumed that the service life of ethylene-propylene rubber seals was 14.8 years at 95% of con-fidence level.