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The Munson Roller on Cylinder Lubricity Evaluator (M-ROCLE) developed at the University of Saskatchewan was used for this survey. Dimensionless Lubricity Numbers (LN), based on wear scar areas and friction coefficients, were employed to evaluate the test fuels and additives. The Canadian seasonal winter and summer, low sulfur diesel fuels were generally found deficient in lubricity (LN<1) on the Munson ROCLE bench test. The locally marketed summer fuels were found to average lower in lubricity than the winter fuels. A number of popular commercial diesel fuel additives were tested and the majority were found to improve the unadditized reference winter diesel fuel lubricity. The most cost effective lubricity additive surveyed was a bio-based product. The overall Lubricity Number coefficient of variation of the individual M-ROCLE data of approximately 5.3% indicated high test precision.

The precision Munson Roller on Cylinder Lubricity Evaluator (M–ROCLE) was used to tribologically evaluate biodiesel additized winter fuel in the laboratory. Eleven biodiesel esters and oil derivatives were prepared, and blended at a 1vol% concentration with a low sulfur, unadditized reference winter diesel fuel. These vegetable–based additives were compared using wear scar areas, coefficients of friction and dimensionless Lubricity Numbers. All of the 1vol% biodiesel blends raised the Lubricity Number of the reference fuel from 0.813 to above the pass/fail value of 1.0. The top 2 lubricity enhancing additives, canola methyl ester and a canola oil derivative, were explored further with tests at treat rates below 1vol% and both were found to be effective at a 0.1vol% concentration. The overall Lubricity Number coefficient of variation of the Munson ROCLE test data was 5.4%, indicating reliable discrimination between fuel samples.

This bench test for lubricity of diesel fuels employs a crossed-axis roller on cylinder geometry. The roller on cylinder lubricity evaluator (ROCLE) yields a dimensionless lubricity number (LN) based on the ratio of wear area stress to Hertzian contact stress, all divided by the stable coefficient of friction. Fuels yielding LN's greater than 1.0 are judged satisfactory. A range of lubricity numbers from 0.5 for kerosene to 1.7 for canola vegetable oil provides good tribological discrimination between various fluids. The addition of 2% canola methyl ester to low sulfur No.1 diesel produces equivalent lubricity to No.2 high sulfur diesel fuel.