This specification covers polyurethane (PUR) in the form of two-component sealing compounds.
This product has been used typically for contact with fuels, but usage is not limited to such applications. Each application should be considered separately. This polyurethane (PUR) has a service temperature range of -65 to +250 °F (-54 to 121 °C) with a continuous fuel service temperature range of -65 to +160 °F (-54 to +71 °C). It may be used for faying surface sealing, wet-installation of fasteners, overcoat of fasteners, sealing joints and seams and, in some cases, as a non-structural adhesive.
NOTE: The use of an adhesion promoter shall be required to obtain proper adhesion.
AMS 3278A results from a Five Year Review and update of this specification.