Sample Engineering Specification

The coil or component shall be protected with a pure
phenolic thermosetting resinous coating. Metal preparation
to provide a surface profile shall include degreasing and
etching, both by immersion.

The coating shall be applied by four (4) consecutive total
immersions. After each of the first three (3) immersions, the
coating shall be partially cured in an oven. Following the
fourth immersion and one (1) spray coat, the coating shall
be totally cured in an oven.

The total dry film thickness [D.F.T.] of the coating shall be
approximately 2 to 3 mils, thereby providing good corrosion
protection without adversely affecting heat transfer.
D.F.T. varies depending on fin spacing and the number of
tube rows in depth. The coating shall withstand dry heat up
to 450 degrees F (232 degrees C) and show no sign of
attack after 3,000 hours of salt spray test to A.S.T.M.
Specification B-117.

The corrosion protection coating shall be Heresite P-413
baking phenolic with plasticizer or approved equal.