O-Ring storage

Seals stored for long periods may change their Storage physical characteristics. Such changes may include hardening, softening, cracking and other forms of surface degeneration. This is due to one or more influences such as deformation, oxygen, light, ozone, heat, damp, oil or a solvent. Basic instructions on storage, cleaning and preservation of elastomer seals are laid down in the DIN 7716 and ISO 2230 standards. ISO 2230 contains advice on storing rubber items. The table below gives the maximum storage periods split into three groups.

Certain conditions must be met when storing rubber products.

Heat
Storage temperature for elastomers should preferably be in the +5°C to +25°C range. Avoid direct contact with heat sources such as radiators or sunlight.
Moisture
Relative humidity should be below 70 % in the storage space. Extremely damp or dry conditions should be avoided.
Light
Elastomer seals should be protected from light when stored. Direct sunlight and strong artificial light with a UV content in particular are to be avoided. We recommend covering windows in storage spaces with red or orange materials.
Oxygen and ozone
If possible elastomers should be packaged or put in airtight containers to protect them from circulating air.
Deformation
Elastomers should be stored in an untensioned condition if possible. Large O-Rings can be stored coiled to save space. If the inside diameter d1  > 300mm, the O-Ring may be looped over once (i. e. in a figure of 8). It should
never be bent.