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As a method for the chipless production of rotationally symmetrical
parts, flow forming ranks amongst those metal forming techniques
which are increasingly gaining in importance. Reserved for many
years for use in the defence industry, this method opens up new
avenues for application in the industries of the future.
The creation of intelligent cost-effective and quality-based
solutions to specific problems frequently requires a departure
from conventional techniques in favour of improved precision
and material saving.
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Empirical values drawn from a wide range of specific customer
applications enable us through the design of tooling and the
control of a number of process parameters to hold much closer
tolerances than other chipless forming processes.
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Typical tolerances, dependent on material |
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Diameter |
: H7 |
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Wall thickness |
: 0,175 mm |
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Straightness |
: 0,1 mm / m |
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Surface finish |
: 0,175 µm |
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The term flow forming is applied where a pre-form is clamped
by a tailstock against a mandrel and rotated during forming.
Using rollers, the metal is made to flow by the application
of a radial load.
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The three principal methods are described below:
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Spinning
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The blank is clamped by a tailstock against the rotating
form tool which matches the internal shape of the finished
part. One or more rolls are applied to form the part to its
final shape in a series of steps.
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Diameter max. |
: 1800 mm |
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Wall thickness max. |
: 15 mm (for steel) |
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Length max. |
: 2000 mm |
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Flow forming
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The term flow forming also encompasses conical flow forming.
The complete wall section between the work rollers and the
mandrel is subjected to a high compressive load and the metal
made to flow.
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Diameter |
: 20 - 650 mm |
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Wall thickness min. |
: 0,10 mm |
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Length max. |
: 4000 mm |
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Starting thickness max. |
: 25 mm (steel)
: 30 mm (aluminium) |
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Shear forming
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Also known as conical flow forming, shear forming enables
conical shapes to be formed directly onto a former. As such
, the method lends itself to the production of seamless hoppers
and cones for defence applications.
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Diameter |
: 0-1800 mm |
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Wall thickness max. |
: 20 mm (steel) |
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Length |
: 600 mm |
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