Study on Medium Resistance of F275 O-Ring Seal Coated with PTFE Film

F275 fluororubber O-ring seal coated with polytetrafluoroethylene (PTFE) film was prepared and the effects of different media on its performance. The coated PTFE film O-ring seal was first prepared according to the aviation industry standards. Then, medium resistance ex-periments in the high temperature aviation kerosene, aviation lubricating oil and the acid-alkali was carrired out. Lastly, the mass, size, Shore hardness and tensile property of the samples were tested. The tensile fracture of rubber sealing ring was observed by SEM. The results showed that although the influence of medium on it is aviation kerosene, aviation lubricant, acidity and alkalinity, the influence on its performance is very small. The maximum reduction of hardness is 5%. The experiment proves that the F275 fluororubber O-ring seal coated with PTFE film has excellent medium resistance. The research results can provide a basis for material selection of rubber seals.