The service life of elastomer materials is not unlimited. Sometimes we need to store elastomer components for a long time to ensure their availability in case of an emergency.
To ensure that stored elastomer parts maintain their properties, we strongly recommend that you follow the storage guidelines according to the following standard DIN 7716. Aspects to be highlighted to extend the shelf life of an elastomer:
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- The storage space reserved for elastomers should be dry and dust-free, as far as possible.
- The storage temperature should be between +5 °C and +25 °C. Under no circumstances should the maximum temperature of +25 °C be exceeded.
- Items should be protected from any source of heat and water condensation. The relative humidity of the environment must be less than 65 %.
- Rubber products should be protected from UV radiation and ozone, preferably in airtight, light-tight packaging.
- The storage environment should be checked for chemicals that may accidentally deteriorate the elastomer of interest.
For more detailed information, please refer to the standard DIN 7716.
These storage guidelines are not exclusive to O-rings, as they can also be used for other items such as hydraulic and pneumatic seals, inflatable seals and flat seals, among other products. For items that have additional metal components, the metal should be checked to ensure that it is free of rust or any other visible defects.
The storage periods for elastic materials are defined by the following standard ISO 2230:
| Ranking |
Initial storage period without technical inspection |
Extension of the initial period after a technical inspection |
| Group A |
5 years |
2 years |
| Group B |
7 years |
3 years |
| Group C |
10 years |
5 years |
Group A elastomers: BR; NR; IR; SBR; AU and EU.
Group B elastomers: NBR; H-NBR; X-NBR; IIR; BIIR; CIIR; CR; ACM; CO and ECO.
Elastomers Group C: CM; CSM; CSM; EPM; EPDM; FKM; FFKM; Q; FQM; PMQ; PVMQ; MQ and VMQ.
Some considerations for the storage of elastomeric materials
The storage period of elastomeric materials may be extended beyond the time indicated in the above table if the product is properly inspected. Similarly, the shelf life of an elastomer material may be reduced before the indicated storage times expire if it is stored incorrectly. In this regard, we refer to the recommendations of the standard DIN 7716.
All these values should be taken with the utmost caution. Elastic materials derived from rubber (elastomers) must have their optimum quality properties. Especially if they are to be used in harsh conditions with chemicals, in high or low temperature environments or in high pressure or vacuum systems.
The final recommendation is that, at the time the item is removed from the shelf, it should be inspected for cracks, cuts, discoloration or other surface changes. If so, the part should be disposed of properly. If not, the part may be returned to service.
