The use of Anton Paar's MCR Tribometer MCR 302 to characterise fuel lubricity is detailed in a newly-published application note.
Fuels pose a special case as lubricants. Due to their low viscosity, they are poor film formers. Thus, wear protection and friction modulation is strongly dependent on the surface-active components and other additives in the fuels.
The wear-protection and friction-modulating properties of fuels can be evaluated by using a high-frequency reciprocating rig test (HFRR; DIN EN ISO 12156-1). A fuel is said to have good lubricity if the diameter of the wear-tracks area is smaller than a critical value; for diesel, the critical HFRR value is 460 μm (DIN EN 590).
