Fuel lubricity

Problems associated with inadequate fuel lubricity were identified in the aeronautical industry in the 1960s, following a succession of in‐flight engine failures. The influence of fuel composition upon fuel lubricity was established, as was the effect of various lubricity additives. Problems associated with inadequate fuel lubricity were also subsequently identified in light‐duty diesel engines when low‐sulphur fuel was introduced. Again, the use of additives or modifications to the refining process overcame the problem at the time, but the continuing trend towards higher injection pressures may require further improvements in current fuel lubricity. The manufacture and use of biodiesel is described, together with the attendant benefits, including use as a lubricity additive in conventional diesel fuel, also disadvantages. The imminent introduction of direct‐injection gasoline passenger car engines has now focused attention on the lubricity of gasoline, which is again likely to become a key issue. Two standardised test procedures for the measurement of fuel lubricities are described.