The use of vegetable oils as fuels and as lubricants has been known for many years. The current environmental awareness has provided a new impetus for developing the so called “green” products by various industries. Most have selected vegetable oils that are more naturally [oxidatively] stable and are suitable for use in industrial applications. Rapeseed, in particular, has been investigated by many European and American companies for development of industrial lubricants.
The purpose of this study, however, has been to investigate the potential utilization of soybean oils as an industrial hydraulic fluid. The results have shown that soybean oils, like other vegetable oils, present good lubricating and wear protection performances. Lack of desired oxidative stability and the subsequent polymerization of the used oil, however, appear to be the main concerns. Three approaches have been selected to address this concern. One is the use of genetically modified soybeans with fatty acid compositions that are more oxidatively stable. The second is the chemical modification of the soybean oils using methyl esters and partially hydrogenated oils. A final approach is the use of various additives and property enhancers to improve performance of the soybean oils in hydraulic systems. While additional tests are being conducted, it is expected that one or more of the three approaches identified will help the development of a soybean based industrial hydraulic oil.
To test performance of the soybean oil in other industrial applications, various soybean oils were tested in a quenchalyzer to study potential use as a quench medium for heat treatment. Preliminary results showed soybean oils to have a better cooling rate than paraffin oils. Actual use in production heat treat environment is underway to study the oils' performances in high temperature applications.