CONTINUOUS WIRE DRAWING PROCESS WITH MECHANICAL DESCALING AND POST-DIE TREATMENT AND APPARATUS

PROCEDE DE TREFILAGE CONTINU A DECALAMINAGE MECANIQUE, AINSI QUE TRAITEMENT ULTERIEUR A LA FILIERE ET APPAREILLAGE

English Abstract

ABSTRACT OF THE DISCLOSURE
The present invention is a process for
drawing and forming a bright wire of a
predetermined diameter and cross-section, from
stock of a greater diameter. It includes the
steps of (a) continuously feeding said stock from
a supply spool through the process; (b)
mechanically removing scale from said stock; (c)
applying a coating of lubricant carrier to the
descaled stock; (d) applying drying air to the
stock with the lubricant carrier thereon; (e)
applying a lubricant to the carrier-coated stock;
(f) drawing the lubricated stock through one or
more pressure dies to decrease the diameter of
the stock down to the desired predetermined
diameter; (g) buffing the drawn stock with a
plurality of buffing wheels, said buffing wheels
being applied to the drawn stock at a plurality
of angles to the direction of travel of the stock
to produce bright wire; and, (h) coiling the
resulting bright wire into coils for subsequent
use. The process is continuous and the speed of
the stock is maintained by conventional drive
mechanisms to feed into the process and to coil

off the process at predetermined speeds. In one
embodiment, mechanical removal of scale includes
the following steps: (i) bending the stock in at
least three different directions over small
enough arcs to cause peeling of scale; (ii)
abrading of the stock to remove any remaining
scale; and, (iii) rinsing the stock to remove any
dust resulting from descaling. The present
invention also includes the apparatus for the
process.

Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A process for drawing and forming a bright
wire of a predetermined diameter and cross-
section from stock of a greater diamerer, which
comprises:
(a) Continuously feeding said stock from a
supply spool through the process;
(b) Mechanically removing scale from said
stock;
(c) Applying a coating of lubricant carrier
to the descaled stock;
(d) Applying drying air to the stock with
the lubricant carrier thereon;
(e) Applying a lubricant to the carrier-
coated stock;
(f) Drawing the lubricated stock through

one or more pressure dies to decrease
the diameter to the desired
predetermined diameter;
(g) Buffing the drawn stock with a
plurality of buffing wheels, said
buffing wheels being applied to the
drawn stock at a plurality of angles to
the direction of travel of the stock to
produce bright wire; and,
(h) Coiling the resulting bright wire into
coils or subsequent use;
wherein all of the steps in the
aforesaid process are continuous, and
the speed of the stock is maintained
by conventional drive mechanisms to
feed into the process and to coil off

the process at predetermined speeds.
2. The process of claim 1 wherein a plurality
of sequential dies are included in step (f)
and each sequential die has a final diameter
less than that of any die preceding it and
the stock is lubricated before each die.
3. The process of claim 2 wherein said
plurality of dies are in a straight line
draw sequence.
4. The process of claim 1 wherein said
mechanical removal of scale in step (b)
includes bending the stock in at least three
different directions over small enough arcs

to cause peeling of scale, and includes
subsequent abrading of the stock.
5. The process of claim 4 wherein said
mechanical removal of scale includes the
following steps:
(i) Bending the stock in at least three
different directions over small
enough arcs to cause peeling of
scale;
(ii) Abrading of the stock to remove any
remaining scale; and,
(iii) Rinsing the stock to remove any dust
resulting from descaling.
6. The process of claim 5 wherein said abrading

is accomplished with a plurality of wire
brushes set at preselected angles to the
path of travel of said stock.
7. The process of claim 5 wherein said rinsing
includes water ringing and pressurized air
wiping.
8. The process of claim 1 wherein said buffing
in step (g) is a dry buffing step.
9. The process of claim 1 wherein said buffing
in step (g) is a wet buffing step.
10. The process of claim 1 wherein after said
buffing in step (g) and prior to coiling,

the stock is coated with a rust-resistant
oil coating.
11. An apparatus for continuous drawing and
forming of a bright wire of a predetermined
diameter and cross-section from stock of a
greater diameter, and includes conventional
drive mechanisms for maintaining the speed
of the stock entering, passing through and
exiting said apparatus, which further
comprises the following units:
(a) A mechanical descaler;
(b) A lubricant carrier feed mechanism for
applying a carrier to the stock;
(c) A lubricant feed mechanism for applying
a lubricant to the stock;

(d) One or more pressure die units, each
having a final diameter less than
that of the original stock and each
having a final diameter less than
that of any preceding dies;
(e) A buffer mechanism including a
plurality of buffers for removing
any carrier and lubricant from the
stock and for buffing and
brightening the stock; and,
(f) A coiler to wind resulting bright
wire.
12. The apparatus of claim 11 wherein lubricant
feed mechanisms are included before each
pressure die unit.

13. The apparatus of claim 11 wherein said
bending means is a plurality of pulleys
arranged sequentially at different angles
and having diameters small enough to have
arcs of travel for said stock which are
capable of causing scale to peel from said
stock.
14. The apparatus of claim 11 wherein said
mechanical scaler also includes an abrading
mechanism downstream from said plural
bending means.
15. The apparatus of claim 12 wherein said
mechanical descaler also includes water
rinsing means and air wiping means.

16. The apparatus of claim 11 wherein said
buffer means is a dry buffing means.
17. The apparatus of claim 11 wherein said
buffer means is a wet buffing means.
18. The apparatus of claim 11 which further
includes anti-rust oil coating means located
after said buffer means and before said
coiler.
19. The apparatus of claim 16 which further
includes anti-rust coating means located
after and adjacent to said dry buffing
means.

20. The apparatus of claim 17 which further
includes anti-rust coating means located
after and adjacent to said dry buffing
means.

Description

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CONTINUOUS WIRE DRAWING PROCESS WITH MECHANICAL
DESCALING AND POST-DIE _R ATMENT AND APPARATUS
The present invention is directed to a
bright wire draw process and apparatus. The
process and apparatus include mechanical scale
removal before pressure die drawing and buffing
after drawing. ~igher speeds and more efficient
production is achieved.
The commerce of bright wire production has
been active for decades and the end use of ~right
wire is very diverse. Metal hangers, nail~,
medical devices, axles, pins~ shaft~, rods,
hooks, etc., are fabricated from bright wire, to

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name a few. The broad hased market for bright
wire includes carbon steel, alloy steel and
stainless steel, as well as others.
~ istorically, metal stock, sometimes called
hot rolled wire or rod, is manufactured from
molten metal and subsequently reworked or sold
for reworking into different sizes (and shapes).
These ~tock rolls have been stretched or drawn
into lesser diametersl for example, through
pressure dies, and have been pretreated to remove
scale or oxides, and have been lubricated to
prevent rapid wear of the dies. Typically,
pretreatment ~or scale removal ~nvolved the use
of acid baths, and, even today, production
facilities may utilize a batch type pickling
proces~ for descaling whereby cranes or hoists

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physically dip rolls of stock into and out of
large heated vats of acid and rinse water and
dryers. ~his descaling operation is costly due
to labor needs, it requires large floor space and
expensive equipment is slow, creates long down
times for bath changes and may cause pollution
problems such as spent acid disposal and acid
evaporation.
Some of the very modern facilities for
drawing bright wire utilize continuous instead of
batch processes, but the wire must be traversed
back and forth over pulley~ in the baths to
provide adequate bath and rinse tlmes. Further,
spent acid, evaporation, floor space and other
problems remain even though the batch method is
supplanted by continuous flow methods.
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Additionally, bright wire production is
achieved by the descaling, drawing and
brightening of the wire product. This
brightening is accomplished by control of limited
or no lubrication to the wire as it passes
through its final draw ~smallest~ last die). The
friction of the die scrapes or otherwise removes
any coatings and yields a bright product. While
this method is acceptable industry wide, it does
cause wear and frequent replacement of the ~inal
die and requires substantlal power to p~11 the
stock through the die by overcoming the
intentional frictional drag.
These problems stated have not been
addressed or overcome by the industry or prior
art until the present invention. For example,

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good continuous draw technology which in many
respects may be today' 5 standard, is exemplified
by the 1923 patent to Ernst Boley as V.S. Patent
No. 1,470,374. ~his patent describes the state
of the art, except for perhaps computerized or
modern speed control systems, but these are not
the subject of the present invention. ln the
~oley method, three or four baths are utilized,
including an acid bath and the problems
pertaining thereto as discussed above are not
eliminated.
To minimize problems of wire resting in acid
baths during down time, ë.g. die change~, etc.,
the art teaches the use of an intermediate wire
collecting and feedinq device as shown in U.S.
Patent No~ 3,354,687 to Walter ~auson. While
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this patent issued more than 40 years after
Boley, it confirms the continuing use of acid
baths for descaling.
The present invention is directed to a
process for drawing and forming a bright wire of
a predetermined diameter and cross-s~ction, from
s~ock of a greater diameter. The process
includes the steps of (a) continuously feeding
said ~tock from a ~upply spool through the
process; (b) mechanically removlng scale from
said stock; (c) applying a coating of lubricant
carrier to the de~caled ~tock; (d) applying
drying air to the ~tock with the lubricant
carrier thereon; (e) applying a lubricant to the
carrier-coated stock; ~ f ) drawing the lubricated
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stock through one or more pressure dies to
decrease the diameter to the desired
predetermined diameter; ~g) buffing the drawn
stock with a plurality of buffing wheels, said
buffing wheels being applied to the drawn stock
at a plurality of angle~ to the direction of
travel of the stock to produce bright wire; and,
(h) coiling the resulting bright wire into coils
for subsequent use. ~he process i8 continuouC
and the speed of the stock is maintained by
conventional drive mechani6ms to feed into the
process and to coil off the process at
predetermined speeds. In one preferred
embodiment of the process, mechanical removal of
~cale includes the following steps: (i) bending
the stock in at least three different directions

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over small enough arcs to cause peeling of scale;
(ii) abrading of the stock to remove any
remaining scale; and, (iii) rinsing the stock to
remove any dust resulting from descaling. The
present invention also includes the apparatus for
the process.
~ he present invention is more fully
understood when the description herein is taken
in conjunction with the drawings appended hereto.
In the drawings:
Figure 1 shows a block diagram of the
present in~ention process and the arrangement of
units in the apparatus of the present invention;
and,
Figure 2 shows a bloc~ diagram of a
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preferred embodiment of the present invention.
The present invention involves bright wire
drawing and especially to improvements both prior
to the stock entering the dies and after the
stock is drawn through the dies.
It is an obiect of the present invention to
elimlnate acid baths and to avoid related
pollution and waste disposal problem~. It's also
an important object of the pre~ent invention to
minimize pressure die wear and replacement and to
provide for decreased energy and costs downstream
from the draw through the dies.
Referring now to Figure 1, hot rolled stock,
e.g. alloy ~teel, is fed from feeder 2 of its
spool to mechanical descaler 4. Here, the scale
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or metal oxide is removed mechanically instead of
by acid bath. Generally, this mechanical scaling
requires b~nding of the stock in a plurality of
directions. In order to maximlze the effect, the
stock shoul d move in a path of arcR wherein the
arcs are of small enough diameter to stress the
stock adequately for the scale to break away or
chip off the stock. In a preferred embodiment,
thiR is followed by abrading and then cleaning of
the stock, e.g. rinse, air, wipe or combination.
As the stock i8 moved down the line by
conventional motor driven systems used in
pressure die drawing, the descaled stock i~ next
~oated with a lubricant carrier at coating unit
6. This is to hold lubricant on the stock for
the draw through he dies. Any available
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2(~5~32
lubricant carrier may be used, such as sodium
borate, lye, lime or other alkali composition.
Next, the carrier is dried or ~baked~ onto
the stock at heating unit 8 and then, at coating
unit 10, the stock i9 coated with a lubricant,
e.g. by solution flow over the moving stock or by
gravity feed and/or mechanically assisted feed of
powder or particulate lubricant. Such lubricants
are typically ~oap, calcium ~tearate or ~odium
stearate or the like.
The stock moves next through one or more
pressure dies having final tiameters of
decreasing ~i~e. ~ypical cross sections are
circular, but other die configurations ar~
possible and these are known in the field. In
preferred embodiments, additional lubricant is
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applied before each die to decrease drag and
increase efficiency and ease of draw.
A critical step iB now applied to the drawn
wire, at buffer unit 14. Here, the product is
buffed with a plurality of buffer~. These
preferably run at diverse angle~, one or more
being at an angle oblique to the direction of
flow of the wire. The brushes may also traverse
back and forth slightly to reduce wearing one
spot on the brushes. Adequate buffing is applied
to remove any remaining lubricant and carrier and
to enhance the brightnes3 of the finished
product.
Normally, thi~ is dry buffing. However, as
shown at optional unit~ 15, the buffing may be
wet buf $ing ( i . e . including application of a
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liquid, e.g. water) and/or the buffing may be
followed by a coater unit to apply an anti-rust
coat, e.g. an oil, to the bright wire product.
Coiler unit 16 runs continuously to coil the
finished product for subsequent shipping or use.
Figure 2 shows one preferred embodiment of
the present invention with respect to mechanical
descaling. The mechanical descaler 4 of Figure 2
is the same generically as that shown in Figure 1
and would be included in the overall present
invention proces~ and apparatus as ~hown in
Figure 1. Thus, Figure 2 depicts in block form
one ~et of preferred substep~ for the invention
shown in Figure 1. Step A, block ~1, shows
bending the stock in at lea~t three dif ferent
directions over small arcs to peel the scale.
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This may be accomplished by reels, rollers or
pulleys or drums, although pulleys afford good
control and provide stability with no sideways
sliding or movement of the stock as it passes
over. The arc~ may be, for example, formed from
a pulley of a five or six inch diameter, given
stock of, for example, one half inch diameter.
In f act, the pulley could be smaller or larger
and stlll efect peellng, except that turns
through very large arc~, e.g. approaching
diameters of half or more of the feed spool,
would be ineffective.
Next ~ at block 2 3, step ~, the stock 1~
abraded to remove remaining scale. The abrasion
is accomplish~d with a plurality of abrading
wheels, e.g. wire brushes, and these are
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preferably set at different angles to the line of
travel of the stock~ -
In ~tep C, block 25, the stock is rinsed to
remove dust and di610dged scale. As shown in
step C-1, block 27, the rinse in this embodiment
is a water rinse. In other embodiments,
mechanical wipers, air blasts, etc., could be
used, but water rinse i~ desired. Also, as shown
in block C-2, step 29, a pressurized air wipe is
used to remove any water remaining after the
rinse.
Referring now to both Figures 1 and 2, the
pref erred embodiment steps shown in Figure 2 are
followed by the subsequent steps shown in Figure
1. Further, preferred embodiments include the
hot buffing and the anti-rust coating steps ~hown
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as optional units 15 in Figure 1.
Obviously, numerous modification andvariations of the present invention are possible
in light of the above teachings. It is therefore
understocd that within the scope of the appended
claims, the invention may be practiced otherwise
than as specifically described herein.