Wire and bar drawing is a metalworking process that reduces the cross-sectional diameter of metal by pulling it through progressively smaller dies. It involves heating the metal, pointing one end, gripping it with pull-in dogs, and pulling it through dies made of materials like tungsten carbide or diamond. Wire drawing uses multiple dies in tandem and winding drums to continuously reduce the diameter, while bar drawing uses a single die. Proper lubrication is important to maintain surface finish and die life during the drawing process.
3. INTRODUCTION
• Wire and bar drawing is a process in which we decrease the diameter or cross-section
of a substance to make into a wire or a bar.
• The main difference in bar and wire drawing is the diameter of the product wire
drawing makes wire while bar drawing makes something bigger than a wire for
example a rebar.
• Bar drawing is done in single draft while wire drawing need many dies because its
diameter is too
small
4. COMPONENTS USED IS DRAWING
:
POINTERS:
Pointers as the name implies
is used to put a taper (or point on the start
end of the wire so that it can be threaded
through the die.
PULL IN DOGS:
Pull in dogs are used to
grip the wire end as it comes through the
die and once the dog is fastend to the block
the wire can be pulled through the die and
will then wrap round the block.
5. DIE:-
Is the tool that shapes the metal to bar or wire some die materials are:-
• 1.TUNGSTEN CARBIDE:
Lowest cost , shock resistance , large
sizes available, lower life expectancy . USED-for
steel wire drawing.
• 2.NATURAL DIAMONDS:
Wear resistance, gives
excellent wire surface, high thermal
conductivity , longer life expectancy
,limited availability in required high quality
&quantity.
6. • 3.SYNTHETIC SINGLE CRYSTAL:
Consistently uniform material ,gives excellent wire surface ,high thermal ,Conductivity ,
larger size ranges are still costly at this time.
• 4.POLY CRYSTALLINE DIAMOND:
Excels in life expectancy ,wear resistance of diamond ,shock resistance
of carbide ,high availability cost effectiveness, high drawing force
,smaller fines requires more filtration, may be
damaged by temperature . above 700c,wire
surface condition less
than from natural diamond.
7. DRAWING PROCESS
• First you need a metal which you need to shape
• You than heat this metal and lubricate it
• Than you need to make it pointy use a pointer
• Than you need a Die
• Now you put the pointy side into the
die and pull it from the other side
and voila the cross-section is reduced
and you get your wire or bar.
8. TYPES OF DRAWING
• Single draft drawing
Bars are drawn in this process
.Hydraulically-operated or
motor-driven carriages are used
for drawing the
bar through the die.
Multiple bars could be
drawn in the draw bench,
using several drawing
dies on the same machine.
9. • CONTINOUS /TANDEM DRAWING
• Wires are drawn by this process .Continuous drawing of wires is done through a series of
drawing dies, with intermediate winding drums. They wind the drawn wire before feeding
it to the next reduction stage. The drum applies mild tension on the wire.Multiple steps of
drawing, also called tandem drawing are required as the reduction of diameter achieved
per pass is usually limited.
10. LUBRICATION
• Lubrication in the drawing process is essential for maintaining good
surface finish and long die life. The following are different methods of
lubrication
• Wet drawing: the dies and wire or rod are completely immersed in
lubricants
• Dry drawing: the wire or rod passes through a container of lubricant
which coats the surface of the wire or rod
• Metal coating: the wire or rod is coated with a soft metal which acts as a
solid lubricant. ( Lubricant example copper sulfate solution)
11. IMPORTANCE
• The wire and bar drawing process had made wires and construction bars available
for mass use and cheap without wires we wont be having so many electrical
equipments . Without constructions bars we would not be able to make these big
tall and huge buildings.
