Manipulation Testing There are several other tests which are often specified by
the aerospace product specifications (Mil-T and AMS) The goal
each of these tests is to verify the ductility of the tubing
material given certain extreme conditions. Examples of these
tests include: Flarability Test, Flange Testing, Flattening, and
Bend Test
Flare Testing - The end of the tube is
expanded to a specified angle creating a new final OD based upon
the original nominal OD of the Tube. This is accomplished by
either spinning or by forcing the end of the rube axially over a
tapered cone. The flared end is then examined for tears and
cracks. The basis for the flare test is to prove that the rube
end can be formed into a pressure tight surface capable of
mating against commercially available pressure fittings.
Flange Testing - Similar to a flare test,
the flange test involves flaring the tube and then turning the
flared end down to form a 90 degree angle with the longitudinal
axis of the sample. This is most easily accomplished by means of
a flaring tool to start the expansion of the tube end, followed
by a die lock and a blunt force to press the flared end over to
be perpendicular to the remainder of the tube. Again, the
objective is to examine the flanged end for cracking or rearing
anywhere on the flanged portion of the end , or anywhere along
the 90 degree bend.
Flatten Testing - The purpose of this test
is to compress the tube between parallel plates. The severity of
the test is determined by the final distance between the
parallel plates as required by testing specification. The test
should be performed with a sample of at least two inches in
length being compressed at room temperatures.
Bend Testing - This test involves a cold bend
of the tubing sample around a mandrel with a diameter controlled
by the individual specification. The ID of the sample may or may
not be supported with filler material dependent upon the
specification being tested against. After bending, the tubing
shall exhibit no tears, crack, breaks, or other flaws.
