Challenges With Precision Boring In The Aerospace Industry

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Challenges With Precision Boring In The Aerospace
Industry
Precision boring of complex aerospace parts
requires good machines, good tools, and
coolants, along with a defined repeatable
process. The difference between a good aerospace
part and a scrapped part can be just a few tenths
of an inch on a bore, but the penalty for a
scrap part can cost big bucks! This is why it is
essential that every kind of scrap is eliminated
in this industry. Aerospace parts are usually
made from hard metals like stainless steel,
titanium, and Inconel all of these materials
being very difficult to precision bore, thus
increasing the expenses involved with the
process. Moreover, precision boring operations
are the last processes to be executed, hence any
scrap due to oversize holes means the hours
invested in milling and threading before the
precious boring all go in vain! In fact, the
price that goes into producing such a scrap part
can at times cost a company its entire monthly
budget! This makes it absolutely essential for
every aerospace part manufacturing company to
develop improved processes to eliminate scrap at
all costs. How to develop an improved
process? One way to achieve the right process is
by first understanding how bore results vary
based on tools with different lengths and
inserts, with different geometries and
sharpness. There are many parameters that
influence the finishing process, which involve
such low-machinability materials and the
operations tight- tolerance requirements. One
solution to overcome all these challenges is by
manufacturing every hole with two passes, with
almost no adjustment in the
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• diameter of the cutting edge in between. The
  first pass if doesnt finish the hole, a second
  spring pass can reach the tolerance. The spring
  pass removes more diameter material than the
  first pass.
• Challenges involved with precision boring
• As mentioned above, the hard metals used to
  manufacture aerospace parts are very difficult
  to precision bore. Thus, high cutting forces are
  applied, which results in more heat generated at
  the tool tip, which leads to stringy and
  difficult-to-break chips. Any abrasion here can
  also result in tool wear.
• Another challenge here is to reasonably predict
  tool deflection, something that is easy with
  soft metals, but not with the hard metals used
  in the aerospace industry. When tool wear is
  combined with harmonics and sharper inserts,
  these hard metals prove to be even more difficult
  to precision bore. Moreover, as the length of
  the tool increases, the more difficult it
  becomes. The process involved is thus
  significantly much harder than with shorter
  softer tools.
• The third challenge is to work out a rule for how
  and when to adjust the boring head. This will
  only come with practice and prediction as to when
  a tool needs to be adjusted.
• The above-mentioned issues are the toughest
  problems, and the most challenging tests one
  could encounter. Nevertheless, engineers are
  always expected to systematically and
  methodically approach every boring problem with
  a solution. After all, every hole in the
  aerospace industry needs to be a completed
  workpiece, which cannot be left undersized,
  cannot be bored oversized, cannot have excessive
  taper, and cannot have bad surface finish. You
  thus need the best precision boring tools in
  Bangalore if youre in the aerospace industry
  and that you can get when you approach FineTech
  Toolings, where every product is
  industry-specific in nature and is in conformance
  to international quality standards.

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