Vinaora Nivo Slider Vinaora Nivo Slider Vinaora Nivo Slider Vinaora Nivo Slider Vinaora Nivo Slider Vinaora Nivo Slider Vinaora Nivo Slider Vinaora Nivo Slider

Rubber O-Rings & Seals shelf life (As at: Oct 2002) (Aerospace/Defence O-Rings)

It must be understood that rubber in relation to Shelf Life is NOT TIME DEPENDANT but STORAGE CONDITION DEPENDANT. Rubber products must be stored in accordance with the standards ISO 2230:2002 & SAE ARP 5316B to be acceptable.

Procurement from defence accredited suppliers/manufacturers who have temperature & humidity controlled facilities that meet the Quality & Standards assures that rubber O-Rings & Seals have been correctly stored & therefore suitable for service.

There have been recent changes to the standards for Controlled Storage of rubber products. The traditional standard was MIL-STD-695 handbook however this has been revised at the request of the U.S. Military/Government. At the same time the U.S government asked for the Rubber Groups to be reviewed, the U.S. Military had a large amount of Nitrile seals that had reached their 10 year age limit & were being disposed of, at a huge cost.

Mr Richard Hamilton, (International Seal Co in the United States) Chairman of the FAA committee & advisor to the U.S. Military on the Rubber Industry in the U.S, was requested to review the old MIL-STD-695 in light of the advances made in the industry since the handbook was issued, Mr Hamilton along with his associates produced the new standard ARP5316B.

The significant change that is most noticeable is to Rubber Group ‘B’, The shelf life of Nitrile has been changed to 15 years service life(Only if the O-Ring/Seal has been packaged to I.A.W standard & has had controlled storage) from its previous 10 year service life.

In addition the Standards Organisation (ISO) has reviewed their standard ISO 2230:2002 (Second edition 2002-04-15) reflecting similar to ARP5316B.

This standard also provides the classifications of Rubber Types according to their susceptibility to deterioration.

There are three(3) Rubber Groups in which all rubber material/types/compounds are classified into, each Rubber Group states the name of the rubber compound & its shelf life. This information is required on Certificates of Conformity, but more importantly identifies to the end user by way of the printing on the packet the shelf life date, it is from this date if the product has been sealed, packaged & labelled per the Standard, the end user can determine if it is suitable for service, the Defence Warehouse can also check the label details before issuing or dispose of the product once it has passed its service life.

The British Standard BS3574 has been the traditional standard used by the RAN & ASC. At this time it has not been reviewed.

ISCA has provided the RAN & ASC with the above information with the view that Navy Rubber Clause“ ‘A’ & ‘B’ ” may require reviewing as a result of the new standards & that OQE also may need updating.