Different grease bases, whats the deal?

[Zukinut]

I've been studying grease the past few days. Most are lithium complex, some are calcium and some are aluminum.

What I can't find the answer to is what are each one best for. It looks like aluminum is best for water resistance. But I could be wrong.

Any help is greatly appreciated. Even if it's just a link for me to read.

Will

 

[KingCake]

http://www.machinerylubrication.com/Read/29995/more-popular-greases
http://www.machinerylubrication.com/Read/29337/understanding-grease-compatibility

that's one of my favorite sites for this kind of info.

 

[Rand]

links dont seem to work?

 

[KingCake]

Originally Posted By: Rand
links dont seem to work?


Looks like their site went down. Was working earlier.

 

[Toaster_Jer]

Seems to be working now.

 

[SD51555]

General rule of thumb I use for what I know is this:

Lithium: Good general purpose grease
Polyurea: Takes heat well
Calcium Sulfonate: Resists washout better
Moly: Handles heavy shock loads better

 

[KingCake]

Originally Posted By: SD51555
General rule of thumb I use for what I know is this:

Lithium: Good general purpose grease
Polyurea: Takes heat well
Calcium Sulfonate: Resists washout better
Moly: Handles heavy shock loads better


Moly isn't a type of grease. You can have lithium soap based grease with moly, etc.

 

[SuperSalad]

Lithium/lithium complex is a good multipurpose grease with decent high temperature and mechanical stability properties. It is a little less waterproof than some other types though. This has historically been the least expensive to make, but lithium prices have been increasing lately so that might not be true in the future.

Aluminum/aluminum complex has very good moisture resistance, decent high temperature compatibility, but its mechanical stability is a little lower than others. This is historically a bit more expensive than lithium.

Modern calcium sulfonates are pretty much good at everything but historically are significantly more expensive than lithium or aluminum.

Polyurea is usually reserved for "lifetime" lubes, enclosed systems not meant to be opened (ie. electric motors and the like).

There are lots of other somewhat more obscure thickeners that each have their own niche applications, but the ones above are probably the most common ones you'll see.

 

[prs]

Some do a few things with superior excellence.

some do most things pretty darn well.

Many do most things passable.

Few, if any, do everything with superior excellence; but we can always hope.

It is commonly agreed that selecting an appropriate type and sticking with it is a good thing. For most of us, it seems that the relatively newer type of polyurea or the lithium complex type are each typically widely available, economical, and do most things really well, if not with superior excellence.

prs