Corrosion Control, NA 01-1A-509. Protective finishes
Protective Paint Finishes
for exterior tube assemblies should be the same as for
Tube assemblies that require paint as a protective
exterior aircraft surfaces specified in NA 01-1A-509.
finish are described in table 10-15. Titanium or
Identification
stainless steel tubing does not require primer or paint
except in areas of dissimilar metals. Primer or paint on
Fabricated tube assemblies should be identified
stainless steel tubing currently installed on naval
before installation or storage. All information from the
aircraft need not be removed. The basic reason for this
identification tag of the removed tube assembly should
is that cracked or damaged paint systems establish a
be transferred to the tag on replacement tube assembly.
differential oxygen concentration cell, which may
Identify the tube assemblies by ink stamping or
result in tubing corrosion damage.
stenciling the part number, manufacturer's code, and
Do not paint interior surfaces of airspeed indicator
other required data on tube assemblies. Apply a
tubing, oxygen, or other plumbing lines. Tube
protective coat of clear varnish over the markings. To
assemblies located inside of an aircraft are interior tube
aid in the rapid identification of the various tubing
assemblies. Tube assemblies located outside of an
systems and operating pressure, each fluid line in the
aircraft are exterior tube assemblies. Interior tube
aircraft is identified by bands of paint or strips of tape
assemblies require a protective finish of two coats of
around the line near each fitting. These identifying
zinc chromate, using application techniques as
media are applied at least once in each compartment.
specified in Aircraft Weapons System Cleaning and
Various other information is also applied to the lines.
Table 10-15.--Prime and Paint for Tube Assemblies
CATEGORY
DESCRIPTION
*PRIME
PAINT
I
Single tube with separate
Prime after forming, but
Tu b e a s s e m b l i e s i n
connectors at each end.
before fabrication.
categories I, II, and III
shall be painted after
II
Prime after forming,
Tube assemblies consisting of
fabrication and before
follow by coating joints
individual tubes permanently
installation, except for as-
with MIL-S-8802 before
joined by nonseparable fit-
semblies in category III,
fabrication.
tings such as those assem-
which have been partially
bled by brazing, welding, and
primed.
swaging and having separable
Partially primed tube
connectors at each free end.
assemblies in category
III
Prime after forming,
Single or multiple tube as-
III shall have additional
follow by coating joints
semblies as in I and II, having
primer applied as required
with MIL-S-8802 before
one or more free ends which
followed by coating of all
fabrication.
must be subsequently joined
nonsealed-nonseparable
permanently to another tube
joints with MIL-S-8802
assembly by brazing, weld-
CAUTION
before application of
ing, and swaging during in-
paint.
stallation.
If primer is not com-
patible to permanent join-
ing process, prime tubing
a suitable distance away
from affected end.
IV
Other tube assemblies not
The cognizant rework facility shall specify the required
described in I, II, or III.
protective finishes.
*Tubing assemblies in categories I, II, and III in which sleeves or ferrules are used in the separable connec-
tions and sleeves or ferrules are fixed in position by deforming one or more numbers, prime up to but not
beyond initial point of contact. Tubing for use with flared systems shall be primed to the end of the tube.
10-36
