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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