Wire drawing is one of the plastic deformation methods
that includes pulling material trough a die and reducing its area which means
tensile force applied to the exit side of the die. Materials which are drawable
must be having high ductility and good tensile strength.
Wires that have diameter 4-5mm can be produced by hot
rolling method. Wires that have smaller in diameter cannot be in required
sensitivity because cooling happens fast and undesirable tinder occurs on the
surface of wire as a result of heat. In addition, wires can break easily
because of huge change on its strength. Because of these reasons sensitive
surface and diameter, good strength can be achieved by cold drawing.
Wire drawing process starts with hot rolled wire rod
in diameter 5.5-11.5mm. In the beginning of the process slugs are removed from
surface with chemical bath or mechanical methods. That operation prevents to
harm die during drawing process. In dry rolling grease and soap dust, in wet
rolling liquid using as lubricant.
Figure 1.0
A wire can pass trough as many as die
untill desired diameter achieved. Every dies continues reducing diameter of
wire. In theory, wire drawing process can be done no material left in the end.
With this reason length of wire grows and volume remains same. Practically some
mechanical differences occurs depens on lubrication kinematics and structure of
material. Some cases material requires intermadiate annealing depends on
reduction applied to area.
Wire drawing also named cold rolling because no heat
applied during drawing process but in smaller diameters, heat occurs while rods
properties change with rolling.
Wire drawing process requires basically drawing
machines, wire rods, lubricants and dies. Also process named as dry or wet drawing.
Hiç yorum yok:
Yorum Gönder