A VERY LITTLE application of grease is useful for viton O rings.
For non-crucial applications (joints on dirty vacuum lines processing large samples) finger grease works well.
Otherwise, and for sliding rings on valves etc., we would recommend a single drop of TorrLube (Sputtered Films Inc., Santa Barbara). Its very
expensive!
Tim Heaton
NERC Isotope Geosciences Lab
Keyworth
Nottingham NG12 5GG, UK
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