These
seals are used in the rotating blade
assemblies of jet turbine engines. They
are designed to wear down from abrasion
by rotating blades and then be periodically
replaced.
Brazing
Application
20 or more of these seals may be used
in an engine. Each seal is brazed
to the backing ring and requires uniform
joint gap and minimum wicking. If
excessive wicking occurs, when the
powder brazing filler metals are used
then the feltmetal will damage the
more complex and costly blade assembly.
Solution
MBF is sandwiched between the backing
ring and feltmetal, fixtured with
an expansion ring, and brazed. Ultra-thin
custom-designed MBF meets the specified
dimensional tolerance to avoid excessive
wicking, simplifies the process, and
eliminates rejects.
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