Lubrication of Ball Screw and Support Bearing

I guess this a ball screw mechanism of a machining operation
Need to look out for water wash out test of each grease to see that. By a rule of thumb polyurea will be better one lasts longer
Barium is heavy metal and only available from Kluber
There are pastes which resist this enviorment and I can suggest you some of them if you would like so.
LOOKING FORWARD TO YOUR response.

If you have a water problem, or "Dampness" with a ball screw application you might consider a silicone based product.
http://huskey.com/ProdInfo/HVS-100.pdf
100% "Waterproof" not "Resistant". proof against most chemicals and washout.
If this particular product doesn't quite meet your needs. Review the sites "Speciality Grease" information. Or just call thier engineers with your problem. I use them extensively in all of our hydroelectric and marine projects. If they don't have a product to meet your needs, they will design one at a very reasonable cost. And they ship worldwide.