Grease identification

[jsethen]

I am not sure if this is even the right place to ask, but...
Can someone help identify which of these are petroleum based? Or can that even be answered with the information provided?

-Aluminum Complex

-Barium

-Calcium

-Calcium 12 hydroxy

-calcium complex

-clay

-Lithium

-Lithium 12-hydroxy

-Lithium Complex

-polyurea

I am trying to get a general compatibility with a grease we are using and the supplier will only say it is compatible with petroleum based products.

Thanks.

 

[electricpete]

I'm no expert but my take is:

Everything you have listed is a thickener. Any of these thickeners are often combined with a base oil to form petroleum based grease.

I struggle a little bit to think of what is not a petroleum based grease. Maybe that refers to synthetic base oils? Any of the above can also be combined with synth base oils.

I would be skeptical of far-reaching claims of grease compability.

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[rmw]

These thickeners that Pete refers to are sometimes referred to as 'soaps'. They are basically used as a carrier for the base oil so that it stays on the lubricated surfaces rather than flowing to the bottom as it does in an oil sump type lubrication system.

Different soaps have different purposes. The lithium soap greases are generally bearing greases, while calcium soaps are for chassis type greases, to the best of my memory.

In a bearing lube, you want a grease to 'flow' into and out of a bearing or gearset, while not 'flowing' away when it becomes hot. In a chassis lube, you want the grease to stay where it is and not flow, as well as not being affected by water, etc, but generally you don't expect it to have to deal with high heat.

Some soaps are to make a grease suitable for high temp applications.

The key thing with greases is not to mix soap types. The interaction of different soaps can cause the oils to separate from the soap. The oil then flows to the bottom of the enclosure due to gravity leaving the soap which is not the lubricant.

High temp greases do not make good low temp bearing greases. They will reside nicely right outside a bearing as it burns up from lack of lubrication, resisting flowing into the bearing, causing failure due to improper lubrication, but surviving quite well just outside the blued and burnt bearing.

There is no 'one size fits all' type of grease. Pay careful attention to the recommendations of the manufacturers of the equipment that you are buying grease for.

rmw