C₅F₁₀O is a promising eco-friendly substitute for insulating gas SF₆ in gas insulated switchgear. Existing research has verified the application feasibility of C₅F₁₀O in terms of dielectric strength, but the compatibility of C₅F₁₀O with the sealing material ethylene-propylene-diene monomer (EPDM) still remains to be tested.In this paper, a 28-day thermal accelerated aging experiment was carried out to study the deterioration behavior of C₅F₁₀O/N₂ and EPDM under long-term coexistence conditions. The compressive modulus of EPDM and the composition changes of C₅F₁₀O/N2 mixture were then determined to evaluate their compatibility with each other.
The results showed that C₅F₁₀O was significantly decomposed after contacting with EPDM, and the decomposition products mainly included CO, CO₂, C₃F₆, C₃F₇H and C₅F₁₀O, among which C₃F₆ and C₃F₇H had the highest concentration. Moreover, in C₅F₁₀O/N₂ environment, the compressive modulus of EPDM also decreased significantly compared to that in pure N₂ environment.
Therefore, EPDM has poor compatibility with C₅F₁₀O. In the application of C₅F₁₀O as an insulation medium, special attention should be paid to the air tightness of the gas chamber, and the maintenance cycle of the sealing material of the equipment should be shortened accordingly.


 

SF6 alternative gas,C5F10O/CO2 mixed gas,compatibility