B&C Technologies IM Series Industrial Ironer - Manual (Page 83)

Chapter 6
Appendix
6.1 Proper Drum Storage
6.1.1 Recommended Storage Life
Most lubricants have supplier recommended shelf lives based largely upon the lubricant’s addi-
tive package. For example, lubricants containing rust inhibitors may lose performance after as
little as six months in storage. Conversely, some turbine fluids with a light additive dose may
be shelved for up to three years. Shelf life information is available from your lubricant supplier
and/or manufacturer for each product used. Employ a FIFO (First In, First Out) rotation of stored
fluids to ensure that lubricant storage life is not accidentally exceeded. And, learn how to read the
coded date on the container label. Shelf life is based on ideal storage conditions for your fluids.
Most manufacturers provide a recommended storage procedure to maximize lubricant shelf life.
The following conditions have been proven to adversely affect a lubricant’s storage life:
Varying Temperatures – Temperature fluctuations will cause movement of air between the atmo-
sphere and the head-space of the container (thermal siphoning). For partially full containers, with
greater head-space, this air movement is increased. Although the drum is sealed and does not leak
lubricant through the bung, a rigid container still inhales air when the temperature drops and ex-
hales as the temperature rises. Along with the air, moisture and small airborne particles enter the
oil container possibly leading to degradation of the base stock and additives. Also, water might
condense within the drum, drop to the bottom and get pumped to the machine during a top-off.
Temperature Extremes – Extreme hot or cold can cause chemical degradation. As mentioned
earlier, rust inhibitors may suffer significant performance losses after only six months of normal
storage. Depending upon the formulation, a rust inhibitor may have poor solubility in base oils
leading to precipitation during storage. This precipitation is greatly accelerated during cold stor-
age.
Humid Environment – Petroleum-based lubricants are hygroscopic. When exposed to humid air,
they naturally absorb airborne moisture. The moisture immediately begins to degrade the additive
package and accelerates oxidation of the lubricant’s base stock once it is put into service.
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