Not even close to true. For instance, see:
http://www.mobilindustrial.com/IND/E...bilith_shc.pdf
"Mobilith SHC greases combine the unique features of synthesized hydrocarbon-based
fluids with those of an advanced lithium-complex thickener, which contribute to excellent
adhesion, structural stability, and resistance to water."
SHC in Mobil's designation is Synthetic HydroCarbon. It is not "filtered on a molecular level", it is synthesized atom by atom to create the desired molecules.
From Wikipedia's entry on grease:
"in the context of lubrication, grease typically applies to a material consisting of a soap emulsified with mineral or vegetable oil. The characteristic feature of greases is that they possess a high initial viscosity, which upon the application of shear, drops to give the effect of an oil-lubricated bearing of approximately the same viscosity as the base oil used in the grease. This change in viscosity is called thixotropy. Grease is sometimes used to describe lubricating materials that are simply soft solids or high viscosity liquids, but these materials do not exhibit the shear-thinning (thixotropic) properties characteristic of the classical grease. For example, petroleum jellies such as Vaseline are not generally classified as greases."
Grease is not a "solution", it is an emulsion. The thickener (e.g. lithium complex soap) is intended to release a little bit of oil under shear, and re-absorb the oil at rest. Kind of like a sponge releasing and reabsorbing water. It's that free oil film that provides the lubrication. A 'pure' lubricant that does not have that property would be too thick to lubricate properly. That slow release of oil is also why grease needs to be replaced after some time - eventually there won't be enough oil left in it to lubricate properly. It's also why anti-seize is preferable for something that's intended to stay assembled for a long time but still come apart.
Sorry, getting technical here, but this
is the tech forum!
Bill
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