DIELESS WIRE DRAWING
Prof. D. Ravi Kumar
Presented By:Rohit Gothwal
•It is manufacturing process of making a wire, generally from
a rod or a bar.
• A bulky process involves a large amount of plastic
deformation is one of the oldest manufacturing processes
•The conventional technique to draw wire is cold
Conventional Wire Drawing
The wire is pulled through a conical aperture called a die to reduce its diameter.
Cemented carbide or diamond
cost is associated with pre-cleaning of the wire prior to entry to the die, tooling, and lubrication
Die wear due to frictional and heating effects can rapidly diminish
High tooling costs associated with it.
Harder the material most is the cost.
Die-less Drawing Process
This innovative method is a semi hot or hot forming
This is a contact free process takes advantage of the
temperature dependency of flow stress to reduce diameter
Wire enters into a heat measurement cooling unit instead
of drawing die.
All die-less wire drawing systems must contain the some basic
A heating device
A cooling device
Purified water and an inert gas
A method of applying a tensile force
Many methods of applying a tensile load have been utilised.
Use of rollers and pay-off wheels.
use of bearings and linear slides in a vertical fashion.
Machine Design and Operation
Designed to produce inﬁnitely variable reductions in mild steel wire
of maximum diameter, 5.0mm at temperatures between 400 and
900◦C at drawing speeds of up to 1.5m/s.
The wire is passed around both roller electrodes
Individual angular velocities are controlled to produce a tensile load
in the wire parallel to its longitudinal axis.
The current to heat the wire was obtained from a 1600A power
The machine, which was controlled by an IBM PC.
The instability of the die-less drawing process coupled with the
complex nature of the machine operation necessitated the use of an
automated data acquisition and machine control system.
Data was acquired for two purposes.
•Primarily, to record the test parameters of the wire.
•Secondly, to record data from the machine transducers to allow
machine control and monitoring to be achieved.
• The system is designed to sufﬁciently control the roller angular velocities
and wire temperature to achieve a desired reduction in the wire diameter.
• A PC based system was used to achieve the aforementioned requirement
due to its cost-effectiveness and ﬂexibility.
• The hardware was controlled by LabVIEW software.
• The user interface consisted of numerous controls and indicators. The
controls allowed the user to input values and choices
Simplified flow chart of machine control and data acquisition
Experiments are conducted on low carbon steel wire of nominal diameter 2.65mm.
Maximum drawing velocity of 1.4 m/s was attained without wire fracture during the drawing
Maximum reduction achieved in cross sectional area during a single pass was 72%. This
reduction was obtained at a test temperature of 780 ◦C.
Variation in wire diameter with
•Absence of die makes the process less expensive as
compare to conventional processes.
•Suitable for materials that have high strength and high
•A large reduction of area can be achieved in single pass.
•Process can be applied to variable cross section bars.