Effect of Automotive Gas Oil Composition on Elastomer Behaviour

Significant differences have been observed in the behaviour of elastomeric seals exposed to various automotive diesel fuels. This behaviour is governed not only by the chemistry of the elastomer but also by the aromatic content of the fuel and is typical of elastomer/fluid interactions occurring under diffusion control.

Although no significant differences were observed in the response of nitrile elastomers exposed to peroxides, the use of antioxidant additives in “low” aromatic diesel fuel needs to be considered.

The normal seal housing design criterion is such that seal integrity should not be compromised by the use of “low” aromatic fuels in normal operating circumstances. Some three years' experience in the Swedish market supports this view.