Storage conditions of elastomer seals
Rubber and other products developed from it are subject to natural aging processes. Modern elastomer materials made by Freudenberg Process Seals however, are stable both regarding the base rubber as well as suitable mixing additives and can therefore be used for a long time. Despite that, some rules have to be observed for storage.
The aging process essentially depends on the following factors:
- Temperature
- Heat
- Sunlight
- Moisture
- Relative humidity
- Ozone and ionizing radiation
- Tensile stress of the component
For these reasons, our elastomer seals should be stored as follows, to maintain their excellent sealing qualities for a long time:
- Storage temperature below 25 °C
- No direct sources of heat in the storage area
- No direct sunlight
- No exposure to ozone and ionizing radiation
- Seals to be stored tension-free as far as possible
Storage and recording storage times of vulcanized rubber products are described in ISO 2230. In this standard, elastomer products are divided into three groups which have been assigned different storage times.
| Group | Materials | Storage time (in years) | Extension (in years) |
|---|---|---|---|
| 1 | NR, AU, EU, SBR | 5 | 2 |
| 2 | NBR, HNBR, ACM, AEM, XNBR, ECO, CIIR, CR, IIR | 7 | 3 |
| 3 | FKM, VMQ, EPDM, FVMQ, PVMQ, FFKM, Fluoroprene® XP, CSM | 10 | 5 |
Other storage extensions are possible under certain circumstances after consulting Freudenberg Process Seals.