HELSINKI, FINLAND – Several working groups reported progress in developing test methods for specific purposes during the European Lubricating Grease Institutes annual meeting here last week.
Joe Kaperick of Afton Chemical, chair of the Working Group on Particle Evaluation, reported that the group is evaluating the Hegman Gauge for pinpointing in grease the number and size of particles, which can contaminate lubricants and potentially cause damage. The device, which is commonly used in the paint industry, could help evaluate greases for suitability in a variety of applications that may be sensitive to various levels of particle contamination. The main limitation for its use in particle evaluation is that the gauge cannot measure the hardness of particles. The working group, which is a joint effort between ELGI and its U.S.-based sister organization the National Lubricating Grease Institute, is identifying laboratories to participate in a round robin test.
The Test Methods Working Group, chaired by Olav Hoeger of Shell Global Solutions, reported that the International Organization for Standardizations Working Group for the Development of Test Methods for Greases (ISO TC 28/WG 19) is progressing with new test methods for oil separation (ISO/WD 22285) and dropping point (ISO/WD 22286). Testing equipment maker Falex is developing a standardized tackiness test, and naphthenics manufacturer Nynas suggested a solution for avoiding toxicity concerns when measuring the aniline point of a grease. Instead, turbidity can be measured and converted in order to determine solubility.
The Biobased Greases Working Group, also a joint effort between ELGI and NLGI, has selected two tests as best for evaluating oxidation stability of such lubricants. These are the Rapid Small Scale Oxidation Test and the Pressure Differential Scanning Calorimetry test, reported chair George Dodos of Eldons S.A. The RSSOT procedure recommended by the group is a modification of ASTM D7545 specially adapted for grease testing. The test is a candidate for a new ASTM standard based on studies carried out by the working group. The recommended PDSC test modifies ASTM D5483 by recommending lower temperature or pressure parameters. The modifications are necessary because standard test methods for evaluating properties of mineral oil based greases do not always provide the most accurate results for biobased products. The group will next turn its attention to measuring low-temperature performance in biobased greases.
The Railway Lubricants Working Group continues its quest for a set of standard tests to approve products that manage friction at the wheel-to-rail interface. The goal is to develop a European standard with regional variations for top-of-rail material. Samples of greases with known performance, both good and bad, have been collected for analysis, reported Constantin Madius of Axel Americas, who is acting chair of the group. Work will also begin to revise the EN 16028:2012 standard for these lubricants.
Once again, mineral oil saturated hydrocarbons and mineral oil aromatic hydrocarbons surfaced as the hot topic for the Food Grade Lubricants Joint Working Group. Concerns about the possible toxicity of these chemicals in products used in food processing has sprung up among consumers in the European Union, and to a lesser degree in the United States, reported working group chair Andreas Adam of Fragol. However, new information has been shared between Concawe, an environmental subgroup of the European Petroleum Refiners Association, and the BfR, Germanys Federal Institute for Risk Assessment, that should result in better acceptance and understanding of MOSH and MOAH found in food, Adam said. Lubricants seem no longer to be on the defensive with this recent knowledge, and greater acceptance should be expected, he later told Lube Report. The working group resolved to draft a position paper on the topic as a tool for educating lawmakers and consumers.