This is the process of thickening a base oil to turn it into a lubricating grease by means of a reaction between metal hydroxides (Li, Ca, Al, Ba) and acids (preferably fatty acids).
These oils are produced using synthesising techniques. They have particularly good viscosity-temperature properties, are stable at low and high temperatures and are resistant to aging. Excellent separating properties. Outstanding lubricant for plastics and elastomers. Names such as polydimethylsiloxane or polyphenylmethylsiloxane describe the special structure of the molecular groups.
This is a method that is used to measure the corrosion protection properties of lubricants for rolling-bearings. This is achieved by adding water to the grease, which is then tested for corrosion over a defined period using self-aligning ball bearings run at a fixed speed and held at rest for specific periods of time, as defined in DIN 51802. If there is no visible corrosion of the test rings then the degree of corrosion is rated 0. The maximum rating is 5, which indicates very heavy corrosion.
A liquid that can dissolve other materials without chemically altering them.
This occurs when the lubricant does not provide a sufficient separating effect, because the start-up friction is higher than the kinetic friction.
Positive interaction of several components, whereby the cumulative effect of individual characteristics is multiplicative rather than additive.
Oils produced by means of chemical processes, as opposed to those extracted from the natural environment (mineral oils, animal and vegetable oils). Certain advantageous properties can be achieved, such as low tendency to carbonise, lower pour point, good resistance to chemicals and, often, excellent viscosity-temperature properties. Lubricants of this type make use of, amongst other substances, synthetic hydrocarbons, ester, polyglycols, fluorinated oils and silicone oils.