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Technical Information i

5.4. Difference Between Cut and Formed Thread

Cold forming is a chip free method of processing, where the workpiece material is being imprinted, the thread is
being formed by plastic deformation, without the need for the material evacuation. The material formed is cold,
and its fibers are not being broken.

Cut Thread Cold formed Thread

Advantages of Forming threads Disadvantages of Forming threads

ŕ chip free processing ŕ much greater forming torques in comparison to
cutting
ŕ one tool for both, through and blind holes
ŕ incomplete formation of a thread top

ŕ possibility to tap deep holes 4xD ŕ thread load carrying capacity amounts to about
80% of the load carrying capacity of the cut
ŕ high durability of thread, especially on side thread, but its strength is much greater
surfaces of a thread pitch
ŕ application range limited to plastic materials
ŕ smoother thread surface
ŕ greater tolerance in the process of threading
ŕ no errors in pitch or form of thread
ŕ method not recommended for food and
ŕ the ability to tap with significantly higher pharmaceutical industry
processing parameters, because the
processing performance of most materials
increases with speed, it has no negative
impact on the tool life

ŕ high rigidity of the tool reduces risk of its
damage

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