Rubber components are susceptible to premature
aging over time. Some factors accelerate this aging process such
: Exposure to UV, ozone and electrical fields. This specification
details the recommended storage conditions and shelf life for
rubber components used in accumulators.
The following rules must be applied to ensure optimum storage
of elastomer parts (bladders etc.)
Note : the complex packaging mentioned below is manufactured and
marketed by OLAER. An alternative but less effective packaging
material is opaque polythene wrapping sealed to prevent free access
of air.
The rules described below are applicable to bladders. These rules
should be adapted as appropriate for other rubber parts.
COMMON RULES
Parts must be stored:
- indoors in a stress (deformation) free condition, inflated to
atmospheric pressure.
- at an ambient temperature below 25ºC.
- relative humidity shall be such that condensation does not occur.
- protected from light sources in particular direct sunlight or
strong artificial light.
- protected from any equipment capable of generating ozone and
electrical fields, e.g. mercury vapour lamps, high voltage equipment,
combustion gases etc.
SPECIAL RULES
Case 1: Without complex packaging
Bladders with "light" valve body in original packaging
or not: store flat (e.g. on shelves)
Bladders with "heavy" valve body : suspended by valve
body.
Case 2: Part in
complex packaging
All types of part: store flat.
The complex packaging is tightly sealed with the bladder slightly
inflated to give them their original form.
The packaging date must be marked on the packaging.
Bladders can be stacked, maximum 3 levels for bladders volumes
> 5L.
Case 3: Part integrated
in an accumulator body
Maintain the bladders inflated at accumulator inflation pressure
P0, or a storage pressure (max.5bar)
In the case of long term storage (exceeding 6 months), bladders
must be stored at storage pressure only (max 5 bar).
STORAGE
PERIOD
The period (in years) indicated guarantees a potential identical
to original potential on de stocking.
The part can be considered as new within this period.
| Rubber |
Case 1 |
Case 2 |
Case 3 |
| Nitrile |
1 |
5 |
5 |
| Hi nitrile |
3 |
5 |
5 |
| Butyl |
3 |
5 |
5 |
| EPDM |
3 |
5 |
5 |
| Neoprene |
3 |
5 |
5 |
| Hydrin |
3 |
5 |
5 |
| Natural Rubber |
1 |
5 |
5 |
| Viton |
2 |
3 |
3 |
|
