基于圆弧模型的氟橡胶密封圈加速老化试验数据处理方法

Data Processing Method Based on Arc Model for Accelerated Degradation Testing of Fluorine Rubber Seal Ring

目的快速评估氟橡胶密封圈的贮存寿命,解决评估过程中经验常数难以确定的问题。方法利用圆弧模型分析高温加速试验过程中φ17.5 mm×2.4 mm规格氟橡胶O形密封圈压缩永久变形随加速老化时间的性能,确定氟橡胶密封圈性能的参数初始值,对性能测试数据进行变换,利用最小二乘法,对圆弧半径和老化时间进行二项式数据拟合,得到某加速温度下圆弧半径与老化时间的数学关系式,进而计算任意老化时间的速度常数,并基于Arrhenius模型进行数据拟合,外推基准贮存温度条件下该型氟橡胶密封圈的贮存寿命。利用5个应力条件下高温加速老化试验的性能退化数据,验证本文提出的数据处理方法。结果通过对试验数据的处理,利用圆弧模型能够评估给出该型氟橡胶密封圈寿命结论为32.2 a,贮存寿命结论与设计要求25 a更为接近。结论基于圆弧模型能够进行有规律退化数据的分析处理,避免了传统数据处理方法中经验常数多次逼近求解过程,具有较高的工程应用价值。

The work aims to evaluate the storage life of fluorine rubber seal rings and solve the problems that is difficult to be determined in evaluation.An arc model was used to analyze the performance of the compression permanent deformation of the fluorine rubber O-ring with φ17.5mm×2.4mm in the process of high temperature accelerated test with accelerated aging time,determine the initial value of the performance parameters of the fluorine rubber seal ring,and transform the performance test data.The binomial data of arc radius and aging time were fitted by the least square method,and the mathematical relation between arc radius and aging time at a certain acceleration temperature was obtained.Then,the velocity constant of any aging time was calculated,and the storage life of the fluorine rubber seal ring under the standard storage temperature was extrapolated based on the Arrhenius model.A high temperature accelerated aging test was designed under 5 stress conditions to obtain performance degradation data and verify the data processing method proposed in this paper.Through the processing of the test data,the longest life of the fluorine rubber seal ring was 32.2 years based on the arc model,and the storage life is closer to the design requirement of 25 years.In conclusion,based on the arc model,regularly degraded data can be analyzed and processed.It avoids the process of solving the empirical multiple approximations in traditional data processing,and has high engineering application value.