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| United States Patent Application |
20120018061
|
| Kind Code
|
A1
|
|
Tyl; Thomas
;   et al.
|
January 26, 2012
|
LIQUID QUENCH
Abstract
A liquid quench is disclosed. In one embodiment, a liquid quench
apparatus for rapidly cooling a metal strand product includes: a chamber
to hold a liquid, configured for placement under a drawn metal stand
product, and defined by a length of a predetermined, adjustable value
selected to create a desired temperature upon the stand product in a
predetermined amount of time; a liquid quenchant disposed within the
chamber with which to cool the strand product; a means to raise the
liquid quenchant above a height of the strand product to rapidly cool the
strand product to the desired temperature in the predetermined amount of
time within the predetermined chamber length; and a means to adjust the
temperature of the liquid quenchant to the desired temperature upon the
stand product. In another embodiment, a system includes an austenitizing
furnace, liquid quench, and air fluidized sand bed.
| Inventors: |
Tyl; Thomas; (Siler City, NC)
; Tyl; Jeffrey Thomas; (Charlotte, NC)
|
| Serial No.:
|
842024 |
| Series Code:
|
12
|
| Filed:
|
July 22, 2010 |
| Current U.S. Class: |
148/559; 266/114; 266/128; 266/130 |
| Class at Publication: |
148/559; 266/114; 266/128; 266/130 |
| International Class: |
C21D 9/52 20060101 C21D009/52; C21D 1/62 20060101 C21D001/62 |
Claims
1. A liquid quench apparatus for rapidly cooling a metal strand product,
the apparatus comprising: a chamber to hold a liquid for placement under
a drawn metal stand product, the chamber defined by a length of a
predetermined, adjustable value selected to create a desired temperature
upon the drawn metal stand product in a predetermined amount of time; a
liquid quenchant disposed within the chamber to raise up and with which
to quench the drawn metal strand product; a means to raise the liquid
quenchant in the chamber to above a height of the drawn metal strand
product above the chamber to rapidly cool the drawn metal strand product
to the desired temperature in the predetermined amount of time within the
adjusted predetermined chamber length; and a means to adjust the
temperature of the liquid quenchant to the desired temperature upon the
drawn metal stand product.
2. The liquid quench apparatus of claim 1, further comprising: at least
one divider to separate the chamber into a plurality of sections to
accommodate a plurality of banks of product, each bank having at least
one drawn stand metal product, wherein each section is independently
filled with the liquid quenchant.
3. The liquid quench apparatus of claim 1, further comprising: at least
one adjustable partition to the chamber with which to adjust the length
of the chamber to the predetermined, adjustable value selected to create
a desired temperature upon the drawn metal stand product.
4. The liquid quench apparatus of claim 1, further comprising: a means to
agitate the liquid quench to change a rate at which heat is removed from
the drawn metal strand product.
5. The liquid quench apparatus of claim 4, wherein the means to agitate
the liquid quench to change the rate at which heat is removed from the
drawn metal strand product comprises a gas introduced into the liquid
quenchant to increase the agitation.
6. The liquid quench apparatus of claim 1, wherein the means to raise the
liquid quenchant above a height of the drawn metal strand product
comprises a lifting pump.
7. The liquid quench apparatus of claim 1, wherein the means to adjust
the temperature of the liquid quenchant to the desired temperature upon
the drawn metal stand product comprises an electrical resistance heater.
8. The liquid quench apparatus of claim 1, wherein the means to adjust
the temperature of the liquid quenchant to the desired temperature upon
the drawn metal stand product comprises a heat exchanger.
9. The liquid quench apparatus of claim 1, further comprising: one or
more water-based chemical additives to add to the liquid quenchant to
modify a rate of heat extraction from the drawn metal strand product.
10. A system for treating a metal strand product, the system comprising:
an austenitizing furnace to heat a strand product to above an A3,
eutectoid, or Acm temperature; an air fluidized sand bed; and a liquid
quench apparatus disposed between the austenitizing furnace and the air
fluidized sand bed, the liquid quench apparatus having: a chamber to hold
a liquid for placement under a drawn metal stand product, the chamber
defined by a length of a predetermined, adjustable value selected to
create a desired temperature upon the drawn metal stand product in a
predetermined amount of time; a liquid quenchant disposed within the
chamber to raise up and with which to quench the drawn metal strand
product; a means to raise the liquid quenchant in the chamber to above a
height of the drawn metal strand product above the chamber to rapidly
cool the drawn metal strand product to the desired temperature in the
predetermined amount of time within the adjusted predetermined chamber
length; and a means to adjust the temperature of the liquid quenchant to
the desired temperature upon the drawn metal stand product.
11. The system of claim 10, further comprising: a first set of rollers to
divert the drawn metal strand product to the chamber for quench by the
liquid quenchant.
12. The system of claim 11, further comprising: a second set of rollers
to redirect the drawn metal strand product from the chamber after quench
by the liquid quenchant.
13. The system of claim 10, further comprising: at least one divider to
separate the chamber into a plurality of sections to accommodate a
plurality of banks of product, each bank having at least one drawn stand
metal product, wherein each section is independently filled with the
liquid quenchant.
14. The system of claim 10, further comprising: at least one adjustable
partition to the chamber with which to adjust the length of the chamber
to the predetermined, adjustable value selected to create a desired
temperature upon the drawn metal stand product.
15. A method of treating a metal strand product, the method comprising
the steps of: utilizing a liquid quench apparatus having: a chamber to
hold a liquid for placement under a drawn metal stand product, the
chamber defined by a length of a predetermined, adjustable value selected
to create a desired temperature upon the drawn metal stand product in a
predetermined amount of time; a liquid quenchant disposed within the
chamber to raise up and with which to quench the drawn metal strand
product; a means to raise the liquid quenchant in the chamber to above a
height of the drawn metal strand product above the chamber to rapidly
cool the drawn metal strand product to the desired temperature in the
predetermined amount of time within the adjusted predetermined chamber
length; and a means to adjust the temperature of the liquid quenchant to
the desired temperature upon the drawn metal stand product; drawing the
metal strand product in a path at least partially defined over the
chamber; and quenching the metal strand product with the liquid
quenchant.
16. The method of claim 15, further comprising: utilizing a lift pump;
raising the liquid quenchant in the chamber to above the height of the
metal strand product; and overflowing the liquid quenchant back into the
chamber.
17. The method of claim 15, further comprising: utilizing an electrical
resistance heater; and adjusting, thereby, the temperature of the liquid
quenchant to the desired temperature upon the drawn metal stand product.
18. The method of claim 15, further comprising: utilizing a heat
exchanger; and adjusting, thereby, the temperature of the liquid
quenchant to the desired temperature upon the drawn metal stand product.
19. The method of claim 15, further comprising: utilizing at least one
divider; dividing the chamber into a plurality of sections to accommodate
a plurality of banks of product, each bank having at least one drawn
stand metal product; and filling, independently, each section with the
liquid quenchant;
20. The method of claim 15, further comprising: utilizing at least one
adjustable partition; and adjusting the length of the chamber to the
predetermined, adjustable value selected, thereby creating the desired
temperature upon the drawn metal stand product.
Description
FIELD OF THE INVENTION
[0001] The technology described herein relates generally to the fields of
metal heat treating processes, strand heating, fluidized sand beds, and
quenching devices. More specifically, the technology described herein
relates to a system and associated methods for a water-based liquid
quench, of variable length and temperature, for use after austenitizing a
plain carbon or alloyed steel strand product from above the A3,
eutectoid, or Acm temperature to below the A1 temperature after which the
strand product enters an air fluidized sand bed.
BACKGROUND OF THE INVENTION
[0002] A quench is a rapid cooling. In materials science, quenching is
used to prevent low-temperature processes such as phase transformations
from occurring by only providing a narrow window of time in which the
reaction is both thermodynamically favorable and kinetically accessible.
By way of example, in the treatment of metal products a quench is the
rapid cooling of a
hot metal object by placing it in a liquid quenchant
in order to harden and strengthen it. The process is particularly suited
for improving the breaking, tensile strength, and ductility of steel wire
as is used in belted vehicle tires.
[0003] Known patents include U.S. Pat. No. 6,228,188, issued to
Meersschaut et al. on May 8, 2001, which discloses a process of patenting
at least one steel wire with a diameter less than 2.8 mm. The cooling is
alternatingly done by film boiling in water during one or more water
cooling periods and in air during one or more air cooling periods. A
water cooling period immediately follows an air cooling period and vice
versa. The number of the water cooling periods, the number of the air
cooling periods, the length of each water cooling period are so chosen so
as to avoid the formation of martensite or bainite. This invention cannot
produce bainite or tempered martensite.
[0004] Known published patent applications include U.S. Patent Application
Publication No. 2008/0011394, field by Tyl and published on Jan. 17,
2008, which discloses a thermodynamic metal treating apparatus and
process utilizing a quenchant mixture of liquid and gas in a cell. Heated
metal is passed over the heated quenchant mixture which contains a liquid
and a gas such as air bubbled through the liquid at a desired rate. The
process is particularly suited for improving the breaking, tensile
strength and ductility of steel wire as is used in belted vehicle tires.
A series of quenching cells allow for fast, uniform treatment of the
metal wire. This method is efficient but more difficult to control since
it uses a liquid quenching cell followed by cooling in foam. Further this
method is limited in application since it cannot produce a tempered
martensitic microstructure. This disclosure is incorporated by reference
herein.
[0005] Other known background art includes using hazardous elements like
lead or hazardous salts to cool material to pearlite or martensite
followed by tempering in lead or a fluidized bed or induction in the case
of a martensitic microstructure.
[0006] Other known background art also includes utilizing an air fluidized
sand bed with or without an air fluidized quenching section held at a
temperature lower than the soaking section of the fluidized bed. This
equipment cools strand product much more slowly than film boiling liquid
quenching resulting in a more coarse pearlitic microstructure. This
method cannot produce tempered martensite.
[0007] The foregoing patent and other information reflects the state of
the art of which the inventors are aware and is tendered with a view
toward discharging the inventors' acknowledged duty of candor in
disclosing information that may be pertinent to the patentability of the
technology described herein. It is respectfully stipulated, however, that
the foregoing patent and other information do not teach or render
obvious, singly or when considered in combination, the inventors' claimed
invention.
BRIEF SUMMARY OF THE INVENTION
[0008] In various exemplary embodiments, the technology described herein
provides a system and associated methods for a water-based liquid quench,
of variable length and temperature, for use after austenitizing a plain
carbon or alloyed steel strand product from above the A3, eutectoid, or
Acm temperature to below the A1 temperature after which the strand
product enters an air fluidized sand bed.
[0009] In one exemplary embodiment, the technology described herein
provides a liquid quench apparatus for rapidly cooling a metal strand
product. The liquid quench apparatus includes: a chamber to hold a liquid
for placement under a drawn metal stand product, the chamber defined by a
length of a predetermined, adjustable value selected to create a desired
temperature upon the drawn metal stand product in a predetermined amount
of time; a liquid quenchant disposed within the chamber to raise up and
with which to quench the drawn metal strand product; a means to raise the
liquid quenchant in the chamber to above a height of the drawn metal
strand product above the chamber to rapidly cool the drawn metal strand
product to the desired temperature in the predetermined amount of time
within the adjusted predetermined chamber length; and a means to adjust
the temperature of the liquid quenchant to the desired temperature upon
the drawn metal stand product.
[0010] The means to raise the liquid quenchant above a height of the drawn
metal strand product can be a lifting pump.
[0011] The means to adjust the temperature of the liquid quenchant to the
desired temperature upon the drawn metal stand product can be an
electrical resistance heater. Alternatively, the means to adjust the
temperature of the liquid quenchant to the desired temperature upon the
drawn metal stand product can be a heat exchanger.
[0012] The liquid quench apparatus also can include at least one divider
to separate the chamber into a plurality of sections to accommodate a
plurality of banks of product, each bank having at least one drawn stand
metal product, wherein each section is independently filled with the
liquid quenchant.
[0013] The liquid quench apparatus further can include at least one
adjustable partition to the chamber with which to adjust the length of
the chamber to the predetermined, adjustable value selected to create a
desired temperature upon the drawn metal stand product.
[0014] The liquid quench apparatus also can include a means to agitate the
liquid quench to change a rate at which heat is removed from the drawn
metal strand product. The means to agitate the liquid quench can be a gas
introduced into the liquid quenchant to increase the agitation.
[0015] The liquid quench apparatus further can include one or more
water-based chemical additives to add to the liquid quenchant to modify a
rate of heat extraction from the drawn metal strand product.
[0016] In another exemplary embodiment, the technology described herein
provides a system for treating a metal strand product. The system
includes: an austenitizing furnace to heat a strand product to above an
A3, eutectoid, or Acm temperature; an air fluidized sand bed; and a
liquid quench apparatus disposed between the austenitizing furnace and
the air fluidized sand bed, the liquid quench apparatus having: a chamber
to hold a liquid for placement under a drawn metal stand product, the
chamber defined by a length of a predetermined, adjustable value selected
to create a desired temperature upon the drawn metal stand product in a
predetermined amount of time; a liquid quenchant disposed within the
chamber to raise up and with which to quench the drawn metal strand
product; a means to raise the liquid quenchant in the chamber to above a
height of the drawn metal strand product above the chamber to rapidly
cool the drawn metal strand product to the desired temperature in the
predetermined amount of time within the adjusted predetermined chamber
length; and a means to adjust the temperature of the liquid quenchant to
the desired temperature upon the drawn metal stand product.
[0017] The system also can include a first set of rollers to divert the
drawn metal strand product to the chamber for quench by the liquid
quenchant. The system further can include a second set of rollers to
redirect the drawn metal strand product from the chamber after quench by
the liquid quenchant.
[0018] The system also can include at least one divider to separate the
chamber into a plurality of sections to accommodate a plurality of banks
of product, each bank having at least one drawn stand metal product,
wherein each section is independently filled with the liquid quenchant.
[0019] The system further can include at least one adjustable partition to
the chamber with which to adjust the length of the chamber to the
predetermined, adjustable value selected to create a desired temperature
upon the drawn metal stand product.
[0020] In yet another exemplary embodiment, the technology described
herein provides a method of treating a metal strand product. The method
includes: utilizing a liquid quench apparatus having: a chamber to hold a
liquid for placement under a drawn metal stand product, the chamber
defined by a length of a predetermined, adjustable value selected to
create a desired temperature upon the drawn metal stand product in a
predetermined amount of time; a liquid quenchant disposed within the
chamber to raise up and with which to quench the drawn metal strand
product; a means to raise the liquid quenchant in the chamber to above a
height of the drawn metal strand product above the chamber to rapidly
cool the drawn metal strand product to the desired temperature in the
predetermined amount of time within the adjusted predetermined chamber
length; and a means to adjust the temperature of the liquid quenchant to
the desired temperature upon the drawn metal stand product; drawing the
metal strand product in a path at least partially defined over the
chamber; and quenching the metal strand product with the liquid
quenchant.
[0021] The method also can include: utilizing a lift pump; raising the
liquid quenchant in the chamber to above the height of the metal strand
product; and overflowing the liquid quenchant back into the chamber.
[0022] The method further can include: utilizing an electrical resistance
heater; and adjusting, thereby, the temperature of the liquid quenchant
to the desired temperature upon the drawn metal stand product.
[0023] The method also can include: utilizing a heat exchanger; and
adjusting, thereby, the temperature of the liquid quenchant to the
desired temperature upon the drawn metal stand product.
[0024] The method further can include: utilizing at least one divider;
dividing the chamber into a plurality of sections to accommodate a
plurality of banks of product, each bank having at least one drawn stand
metal product; and filling, independently, each section with the liquid
quenchant;
[0025] The method also can include: utilizing at least one adjustable
partition; and adjusting the length of the chamber to the predetermined,
adjustable value selected, thereby creating the desired temperature upon
the drawn metal stand product.
[0026] Advantageously, the technology described herein is completely
non-hazardous and can be completely environmentally friendly when an
electrically heated fluidized bed is used. Also advantageously, the
technology described herein provides for multiple chemistries and
diameters to be processed simultaneously. Furthermore, no other
technologies allow for direct measurement of strand product temperature
before and after quenching. Still furthermore, no other technologies can
produce a suitable microstructure when desiring pearlite, bainite or
tempered martensite.
[0027] There has thus been outlined, rather broadly, the more important
features of the technology in order that the detailed description thereof
that follows may be better understood, and in order that the present
contribution to the art may be better appreciated. There are additional
features of the technology that will be described hereinafter and which
will form the subject matter of the claims appended hereto. In this
respect, before explaining at least one embodiment of the technology in
detail, it is to be understood that the invention is not limited in its
application to the details of construction and to the arrangements of the
components set forth in the following description or illustrated in the
drawings. The technology described herein is capable of other embodiments
and of being practiced and carried out in various ways. Also, it is to be
understood that the phraseology and terminology employed herein are for
the purpose of description and should not be regarded as limiting.
[0028] As such, those skilled in the art will appreciate that the
conception, upon which this disclosure is based, may readily be utilized
as a basis for the designing of other structures, methods and systems for
carrying out the several purposes of the present invention. It is
important, therefore, that the claims be regarded as including such
equivalent constructions insofar as they do not depart from the spirit
and scope of the technology described herein.
[0029] Further objects and advantages of the technology described herein
will be apparent from the following detailed description of a presently
preferred embodiment which is illustrated schematically in the
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] The technology described herein is illustrated with reference to
the various drawings, in which like reference numbers denote like device
components and/or method steps, respectively, and in which:
[0031] FIG. 1 is a schematic diagram of a system for the treatment of
metal wire products illustrating system components and the wire path
direction through an austenitizing furnace, liquid quench, and air
fluidized sand bed, according to an embodiment of the technology
described herein;
[0032] FIG. 2 is a side view schematic diagram of a liquid quench system,
illustrating, in particular, an inner chamber to hold a liquid quenchant
and the liquid lift and overflow at the wire path, according to an
embodiment of the technology described herein; and
[0033] FIG. 3 is a top view schematic diagram of a liquid quench system,
illustrating, in particular, one quenching tank and two wire banks and
movable dividers to change a quench length within each wire bank,
according to an embodiment of the technology described herein.
DETAILED DESCRIPTION OF THE INVENTION
[0034] Before describing the disclosed embodiments of this technology in
detail, it is to be understood that the technology is not limited in its
application to the details of the particular arrangement shown here since
the technology described is capable of other embodiments. Also, the
terminology used herein is for the purpose of description and not of
limitation.
[0035] In various exemplary embodiments, the technology described herein
provides a system and associated methods for a water-based liquid quench,
of variable length and temperature, for use after austenitizing a plain
carbon or alloyed steel strand product from above the A3, eutectoid, or
Acm temperature to below the A1 temperature after which the strand
product enters an air fluidized sand bed.
[0036] Kirchhoff's Law states: dH=dHt+(integral) (dCp)dT. The first term
is the heat of transformation of austenite into the final desired
microstructure. The second term relates to the specific heat of the
material and is the amount of thermal energy that must be removed from
the product at the austenitizing temperature to reach the desired soaking
temperature. It is not unusual for the second term to exceed the
magnitude of first term by an order of magnitude. In the technology
described herein the second term relates to the quench, and the first
term relates to the fluidized bed. If an air fluidized sand bed without a
liquid quenchant is use to remove heat related to the second term, the
heat transfer rate is generally too slow to produce a suitable
microstructure like fine pearlite, pure bainite, or pure martensite when
realistic manufacturing speeds are employed. Further, common air
fluidized sand beds have a fixed quenching length that limits the type of
steel, speeds, and diameter of products that can be heat treated
simultaneously.
[0037] The technology described herein provides a quench of variable
length and temperature that can be used in combination to reach the
desired temperature before entering the air fluidized sand bed, removing
most or all of the heat related to the second term. In this case the
fluidized bed is used only to absorb heat related to the first term (heat
of transformation), or in the case of tempering martensite, to raise the
steel to the appropriate tempering temperature. Further, the quench can
be designed to process wires in "banks" where a bank of material is
defined as adjacent wires that are moving at approximately the same
speed, have approximately the same diameter and are approximately the
same chemistry. For example, if 60 strands of wire are being heat treated
simultaneously in the same austenitizing furnace the wires can be broken
into several banks of wires e.g. six banks of ten wires. Each bank of
material can be processed through a quench each of which has a different
quenching length, quenching temperature and quenching agitation before
entering the air fluidized sand bed. In this example six wire diameters,
chemistries and speeds can be used all reaching the desired temperature
after quenching and all resulting in the desired microstructure. Since
the quenching length and temperature is not fixed (like in a conventional
air fluidized sand bed) an infinitely larger range of diameters, speeds
and chemistries of wire can be produced simultaneously compared to a
conventional air fluidized sand bed.
[0038] A water based liquid quench is disclosed. The liquid quench is
constructed of variable length and temperature. The liquid quench is
adapted for use after austenitizing a plain carbon or alloyed steel
strand product from above the A3, eutectoid or Acm temperature to below
the A1 temperature after which the strand product enters an air fluidized
sand bed. In use, the liquid quench can provide a quench to a metal
strand product in various scenarios.
[0039] In a first case the strand product is quenched below the martensite
finish temperature, completely transforming the strand product to
martensite. In this first case the air fluidized sand bed is used to
temper the martensite.
[0040] In a second case the strand product is quenched to some temperature
above the appropriate TTT (Time, Temperature, Transformation) curve
"nose" resulting in a microstructure of unstable austenite and possibly
some pearlite. In this second case the air fluidized sand bed is used
hold the strand product at some temperature near or above the "nose" of
the TTT curve resulting in a pearlitic microstructure.
[0041] In a third case the strand product is quenched to some temperature
below the appropriate TTT curve "nose" resulting in a microstructure of
unstable austenite and possibly some pearlite or bainite. In this third
case the air fluidized sand bed is used to hold the strand product at
some temperature near or below the "nose" of the TTT curve but above the
martensite start temperature resulting in a bainitic microstructure.
[0042] In all cases the water-based quenchant is controlled to either
eliminate film boiling when a martensitic microstructure is desired or to
promote film boiling on the surface of the
hot work-piece when a
pearlitic or bainitic microstructure is desired to prevent formation of
unwanted microconstituents or microstructures on the material's surface.
The quenchant may contain small amounts of water soluble chemicals to
promote or avoid film boiling. In all cases the temperature of the water
based quenchant is maintained at an appropriate temperature to produce
the desired final microstructure.
[0043] Referring now to the Figures, a liquid quench 14 is shown. Liquid
quenching is utilized, for example, to remove heat related to
austenitization and transformation to martensite. The liquid quench
apparatus 14 includes a chamber 30 to hold a liquid for placement under a
drawn metal stand product 18. The chamber 30 can be defined as an outer
chamber 30 to catch overflow 36 of the liquid quenchant and an inner
chamber 28 to hold the liquid quenchant 24. The inner chamber 28 is
defined by a length of a predetermined, adjustable value selected to
create a desired temperature upon the drawn metal stand product 18 in a
predetermined amount of time. In at least one embodiment, the chambers
28, 30 are stainless steel.
[0044] The liquid quench apparatus 14 includes a liquid quenchant 24
disposed within the inner chamber 28 to rise up and with which to quench
the drawn metal strand product 18. The liquid quench apparatus 14
includes a means to raise the liquid quenchant 24 in the inner chamber 28
to above a height of the drawn metal strand product 18 above the chamber
to rapidly cool the drawn metal strand product 18 to the desired
temperature in the predetermined amount of time within the adjusted
predetermined chamber length.
[0045] In at least one embodiment, the means to raise the liquid quenchant
24 above a height of the drawn metal strand product 18 is a lifting pump
20. As depicted in the Figures, pump 20, in direction 22, provides a
liquid flow to the inner chamber 28 to lift the liquid quenchant 24 above
the drawn metal strand product 18 as shown in direction arrow 26. The
lifted liquid 34 is shown raised and covering and overflowing the drawn
metal strand product 18 as it quenches. In use, the pump 22 is sufficient
to circulate the liquid quenchant 24 from the overflow tank into the
quenching tank with sufficient flow and pressure to raise the liquid
above the wire height.
[0046] The liquid quench apparatus 14 includes a means to adjust the
temperature of the liquid quenchant 24 to the desired temperature upon
the drawn metal stand product 18. In at least one embodiment, a heat
exchanger is utilized with pump 20 through which the liquid quenchant 24
is passed. By way of example, the heat exchanger is used to lower the
temperature of the liquid quenchant 24. In at least one embodiment, an
electrical resistance heater is utilized to adjust a temperature of the
liquid quenchant 24. By way of example, the temperature of the liquid
quenchant 24 is raised by the electrical resistance heater.
[0047] The liquid quench apparatus 14 includes at least one adjustable
partition 32 to the inner chamber 28 with which to adjust the length of
the inner chamber 28 to the predetermined, adjustable value selected to
create a desired temperature upon the drawn metal stand product 18. As
depicted the adjustable partition 32 is moved as shown by arrow 38 to
increase or decrease the inner chamber length.
[0048] The liquid quench apparatus 14 can be divided to include multiple
cells or sub chamber through which metal strand product 18 is drawn. As
depicted divider 40 creates to sub-chambers to accommodate a plurality of
banks of product 18, each bank having at least one drawn stand metal
product 18, wherein each section is independently filled with the liquid
quenchant 24. The length of each chamber section can vary.
[0049] The liquid quench apparatus 14 can include a means to agitate the
liquid quenchant 24 to change a rate at which heat is removed from the
drawn metal strand product 18. By way of example, in one embodiment, the
means to agitate the liquid quenchant 24 to change the rate at which heat
is removed from the drawn metal strand product 18 is a gas introduced
into the liquid quenchant 24 to increase the agitation.
[0050] The liquid quench apparatus 14 can include one or more water-based
chemical additives to add to the liquid quenchant 24 to modify a rate of
heat extraction from the drawn metal strand product 18.
[0051] The liquid quench apparatus 14 can include, for pearlitic and
bainitic microstructures, a series of baffle plates above the quenching
pump inlet to the quenching tank so that the liquid is non-turbulent or
relatively still as the wire passes through the liquid. This
configuration promotes stable film boiling. Additionally, or
alternatively, the liquid quench apparatus 14 can include, for
martensitic microstructures, a system to agitate the quenching bath like
a liquid lifting impeller in the quenching tank when strand product is
passed through the quenchant. This configuration helps eliminate stable
film boiling.
[0052] In use, the liquid quench apparatus 14 provides a quench to a drawn
metal strand product 18 exiting an austenitizing furnace 12. The
austenitizing furnace 12 heats the metal strand product 18 to above an
A3, eutectoid, or Acm temperature. By way of example, the austenitizing
furnace 12 is a direct fired gas furnace through which all strand product
18 passes, and wherein the strand product 18 reaches a temperature
between 870 C-1020 C.
[0053] In at least one embodiment, subsequent to the liquid quench
apparatus 14, an air fluidized sand bed 16 is utilized, for example, to
remove the heat of transformation from austenite to pearlite or bainite.
Additionally, the air fluidized sand bed 16 can be utilized to temper
martensite. The air fluidized sand bed 16 is of an appropriate length to
hold the strand product 18 at temperature for 4-10 seconds. The air
fluidized sand bed 16 includes a method to control the amount (pressure
and volume) of fluidization air and the sand temperature.
[0054] In use the liquid quench 14 is placed between an austenitizing
furnace 12 and an air fluidized sand bed 16. To facilitate proper
movement of the drawn metal strand product 18, series of rollers can be
utilized. In at least one embodiment, a first set of rollers is utilized
to divert the drawn metal strand product to the inner chamber 28 for
quench by the liquid quenchant 24. In at least one embodiment, a second
set of rollers is utilized to redirect the drawn metal strand product 18
from the inner chamber 28 after quench by the liquid quenchant 24.
[0055] When rollers are used to change the wire path 18, a method to
change the length of the quenching device is provided by moving the
rollers parallel to the wire direction. Alternatively, a set of cells
parallel to the wire direction, each of which can be filled independently
to increase or decrease the quenching length, are utilized. When rollers
are not used, a method to change the length of the quenching device is
provided. By way of example, a partition movable parallel to the wire
direction is utilized.
[0056] In summary the quenching device can have a means to control the
temperature of the liquid, the liquid quenchant can contain one or more
water based chemicals to change the ability to extract heat from a strand
product, the quenching device can be divided into banks to lower the
temperature of adjacent wires, the quenching device can have a method of
varying the quenching length, the quenching device can have a method of
agitating the quenchant to change the rate at which heat is removed from
the product, the quenching device can have a method to introduce a gas to
increase the agitation of the quenchant and change the rate at which heat
is removed from the product
[0057] The technology described herein provides a method for the treatment
of a metal strand product utilizing a liquid quench. The method includes
one or more of the followings steps, and as one of ordinary skill in the
art will appreciate, upon reading this disclosure, the order and
selection of the various method steps can vary based upon specific
applications: [0058] utilizing a liquid quench apparatus having: a
chamber to hold a liquid for placement under a drawn metal stand product,
the chamber defined by a length of a predetermined, adjustable value
selected to create a desired temperature upon the drawn metal stand
product in a predetermined amount of time; a liquid quenchant disposed
within the chamber to raise up and with which to quench the drawn metal
strand product; a means to raise the liquid quenchant in the chamber to
above a height of the drawn metal strand product above the chamber to
rapidly cool the drawn metal strand product to the desired temperature in
the predetermined amount of time within the adjusted predetermined
chamber length; and a means to adjust the temperature of the liquid
quenchant to the desired temperature upon the drawn metal stand product;
[0059] drawing the metal strand product in a path at least partially
defined over the chamber; [0060] quenching the metal strand product with
the liquid quenchant; [0061] utilizing a lift pump; [0062] raising the
liquid quenchant in the chamber to above the height of the metal strand
product; [0063] overflowing the liquid quenchant back into the chamber;
[0064] utilizing an electrical resistance heater; [0065] adjusting,
thereby, the temperature of the liquid quenchant to the desired
temperature upon the drawn metal stand product; [0066] utilizing a heat
exchanger; [0067] adjusting, thereby, the temperature of the liquid
quenchant to the desired temperature upon the drawn metal stand product;
[0068] utilizing at least one divider; [0069] dividing the chamber into a
plurality of sections to accommodate a plurality of banks of product,
each bank having at least one drawn stand metal product; [0070] filling,
independently, each section with the liquid quenchant; [0071] utilizing
at least one adjustable partition; and [0072] adjusting the length of the
chamber to the predetermined, adjustable value selected, thereby creating
the desired temperature upon the drawn metal stand product.
[0073] Although this technology has been illustrated and described herein
with reference to preferred embodiments and specific examples thereof, it
will be readily apparent to those of ordinary skill in the art that other
embodiments and examples can perform similar functions and/or achieve
like results. All such equivalent embodiments and examples are within the
spirit and scope of the disclosed technology and are intended to be
covered by the following claims.
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