GIS设备用三元乙丙橡胶密封材料老化前后力学性能变化研究

Study on Mechanical Property Variation of EPDM Sealing Materials for GIS Equipment Before and After Aging

GIS设备用三元乙丙(EPDM)橡胶密封材料长期使用会出现老化现象,严重的还会使密封失效进而造成严重的事故。因此文中采用热氧老化的方法同时研究了密封圈与密封条两种不同形态的EPDM橡胶样品于老化前后的力学性能变化,为EPDM在GIS设备中长期应用提供指导。结果表明,邵氏硬度会随着老化时间的增加而逐渐变大,拉伸强度会先增大后减小,而断裂伸长率则会一直减小。将密封圈和密封条的性能作对比,发现密封圈和密封条的性能变化趋势相同,但在变化过程中,密封条的邵氏硬度、拉伸强度和断裂伸长率均大于密封圈。

The long-term use of EPDM rubber sealing material for GIS equipment will occur aging phenomenon and will,in case of serious condition,lead to the sealing out of function as well as cause serious accident.Therefore,the thermal oxygen aging method is used in this paper to study the mechanical property variation of such two forms of EPDM rubber samples as sealing ring and sealing strip before and after aging,so to provide guidance for the long-term application of EPDM in GIS equipment.The results show that the Shore hardness will gradually increase with the increase of aging time,the tensile strength will increase firstly and then decrease,but the breakage elongation will always decrease.It is found by comparing the performance of the sealing ring and the sealing strip that the performance variation of the sealing ring and the sealing strip has the same trend,but in the process of the variation,the Shore hardness,tensile strength and breakage elongation of the sealing strip are greater than those of the sealing ring.