"Shelf life" is the length of time that a product is deemed suitable for use without re-testing its physical characteristics (kept in storage condition recommended by the

Manufactures).

Nye Food-grade lubricants have 4 years Shelf life. Nye usually estimates "Shelf life" from ship date.

"Function life" is lifetime/durability of a product.

Synthetic oils are inherently stable materials. Generally, they are not expected to oxidize, polymerize or volatilize at room temperature for 10 years or more. Nye have regularly conducted tests to check the quality of certain very delicate synthetic hydrocarbon precicion bearing oils five years after manufacture and have detected no degradation. Ester oils, where the ester linkage maybe subject to a minute degree of hydrolysis in the presence of moisture, could become more acidic if moisture is present. Fluorinated oils and silicones are not likely to be affected by simple aging.

For greases, its quality could be affected by a change in the gel structure. If the gel contracts or become softer should do retest before use.

For more detail, please visit: https://www.nyelubricants.com/faq#3566

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