Lubricity Properties of High Temperature Jet Fuel

The effects of fuel additives and naturally occurring fuel components and impurities on the lubricity of JP-5 were determined. The ball-on-cylinder machine was used as a lubricity tester. Naturally occurring hydrocarbon compounds had very little effect on the lubricity of JP-5. Corrosion inhibitors, organic acids and nitrogen containing compounds were found to improve lubricity while sulfur compounds, non-acid oxygen containing compounds and anti-oxidants had little or no effect on lubricity. The compounds that were effective lubricity improvers did so by keeping dissolved oxygen from reaching the metal surface of the ball-on-cylinder machine and reacting there.