US 3154442 A
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Description (OCR text may contain errors)
Oct. 27,- 1964 M. A. NYE ETAL 3,154,442
APPARATUS AND PROCESS FOR CONTINUOUSLY HEAT TREATING WIRE AND THE LIKE Filed May 19, 1961 FIG I INVEN TOR. .MAURICE A. NYE a JESS C. BlTl'MAN ATTORNEYS United States Patent 3,154,442 APPARATUS AND PROCESS FOR CONTINUOUSLY HEAT TREATING WHQE AND THE LIKE Maurice A. Nye and Jess C. Bittman, Cuyahoga Falls,
Ohio, assignors to The Vaughn Machinery Company,
Cuyahoga Falls, Ohio, a corporationof Ohio Filed May 19, 1961, Ser. No. 111,244 Claims. (Cl. 148144) This invention relates to the continuous patenting and treating of steel wire and, more particularly, to a novel apparatus and method for accomplishing same.
Patenting is defined in the art as a heat treatment applied to steel wires and rods having a carbon content of 0.25 percent and higher to obtain a sorbitic structure having high tensile strength, ductility and the ability to withstand hard drafting. Patenting is generally conducted as a continuous process and consists in first heating the material considerably above its critical temperature, then cooling through the critical temperature at a comparatively rapid rate. The cooling step may be conducted in open air or by immersion of the wire into a lead bath. The lead bath method has been generally preferred in the art for the reason that it is easier to control and thereby to produce definite grain structures in the material. Further, the lead bath cooling method results in less scale being produced on the wire. Frequently, however, it is desired to produce a patented wire that has no residual lead on its surface. Moreover, the removal of the residual lead may be impractical or uneconomic in certain cases.
Conventional patenting methods are generally continuous only during the heating and cooling steps, whereas any subsequent treatment of the wire such as cleaning, coating and coiling may be separately conducted thus breaking up the continuity of the whole wire treating operation. Further, in conventional patenting the wire is fed at a relatively low lineal speed (e.g., about 40 feet per minute) which fails to keep up with other processing at high speeds (e.g., about 600 feet per minute). This necessitates either a plurality of patenting equipment or use of numerous supply coils, spoolers, etc., resulting in poor uniformity of the Wire.
It is an object of this invention to provide an apparatus and method for the continuous patenting and treatment of steel wire at high speeds.
Another object is to provide such an apparatus and method wherein the cooling step may be at least partially conducted in ambient air while maintaining accurate control.
A further object is to provide such an apparatus and method wherein the patenting of the steel wire is conducted continuously at high speeds with the subsequent steps of cleaning, coating, drying and coiling, all as part of one continuous operation.
A still further object is to provide such an apparatus and method wherein any scale present on the wire may be removed before patenting and treating as part of one continuous operation.
Another object is to provide such an apparatus and method which will materially reduce the amount of equipment required.
Other objects and advantages of the present invention will become apparent as the following description proceeds.
To the accomplishment of the foregoing and related ends, the invention, then, comprises the features hereinafter fully described and particularly pointed out in the claims, the following description and the annexed drawings setting forth in detail certain illustrative embodiments of the invention, these being indicative, however, of but a few of the various ways in which the principle of the invention may be employed.
In said annexed drawings:
FIG. 1 is an elevation view of the apparatus of this invention.
FIG. 2 is a plan view of the apparatus of this invention.
FIG. 3 is an elevation view of a scale breaker, die and storage block for optional use in the invention.
In reference to the drawings, the wire 1 to be treated is removed from coils 2 which are shown mounted on racks 3. To facilitate wire removal these racks 3 preferably have a tilted base and a bar 4 in the position shown to effect removal of the wire one convolution at a time. The wire is only taken from one coil, but to aid in continuity of operation another coil 2a is mounted on a rack 3a next to rack 3 and the leading end of the wire from coil 2a is connected to the trailing end of wire from coil 2. As the coil 2 from rack 3 is used up and the wire from 2a is being used, a new coil is mounted on rack 3 and connected to the trailing end of the Wire from rack 3a. The wire 1 is tensioned by running it through a series of pinch rolls 5. If the wire has any undesirable scale thereon, this may be removed prior to tensioning by, first, running it over the series of small diameter sheaves 6 to break up the scale and, second, by running the wire through die box 7 to physically scrape off the broken-up scale. Storage block 8 is another optional modification that can be used with or without the scale removal means. The storage block 8 has a push-up flange 9 at its base along which the wire 1 is introduced. The block is equipped with rotating drive means (not shown) which may be of any suitable construction known to those skilled in the art. The wire 1 is wound on the block 8 and may be continuously removed therefrom over the sheave 10 which is mounted on the overhead arm 11. This storage block structure enables the wire either to be continuously removed as it is wound on the block 8, or it can be continuously removed after a stored amount is wound on the block 8 which is no longer rotating. If the storage block 8 is used, the wire 1 is taken therefrom and run through the rollers 5 previously described.
As the wire is removed from the tensioning operation it is wound on rotating take-up block 12 along a push-up flange 13 located at the base of the block. The block contains suitable drive means (not shown) at its base to effect rotation thereof. The action of the push-up flange 13 is such that a coil of wire will be continuously, helically advanced upward along the block 12. The upper end of the block 12 is surrounded by a heating furnace 14 which is shown in the shape of a dome. The interior surface of the furnace 14 may contain suitable heating means (not shown), e.g., burners, electrical heating coils, or any other suitable heating device known to those skilled in the art. A block and furnace suitable for used as described herein is disclosed in the US. application of Nye et al., Serial No. 55,651, filed September 13, 1960, now Patent No. 3,098,109. As the wire helically advances along the block 12 into the furnace 14 heat is continuously and uniformly applied to the wire at a temperature substantially above its critical point, e.g., about 1750 F. This structure of the furnace and block enables an extremely rapid lineal speed of the wire, e.g., about 1000 feet per minute, while enabling accurate and adequate heat treatment of the wire in a relatively small volume of space. The furnace 14 is provided with an opening 15 wherein the wire is tangentially removed from the block 12 and introduced to the cooling take-up block 16 which is situated closely thereby. The block 16 is also equipped with a push-up flange 17 along its base along which the wire 1 is introduced and likewise is adapted for rotation by suitable drive means in its base (not shown). A suitable liquid and vapor cooling device for this step is disclosed in the US. application of Nye et al., Serial No. 46,542, filed August 1, 1960, now Patent No. 3,064,798. As the block 16 is driven, the wire continuously, helically advances in a coil up the surface of the block 16. The body of the block 16 may be equipped for internal liquid cooling (not shown) which will serve to cool the wire in contact with the block and at the same time the wire is being cooled by its high speed rotary contact with the ambient air. Also, a spray of water vapor may be directed at the coil to speed the cooling. This method and device for cooling the wire again permits a rapid rate of wire travel in a small volume of space whereby a reasonably rapid rate of cooling is effected immediately after the heat treating step.
The wire 1 is then tangentially removed from the block 16 and drawn over sheave 18 and into liquid cooling bath 19, which may contain water or any other suitable liquid heat transfer medium. The bath is. provided with two sheaves 20 over which the wire 1 is wound; the number of turns around the sheaves 20 may be varied according to the temperature of the liquid, the final temperature desired in the wire, the incoming temperature of the wire, etc. Normally the wire when it leaves block 16 will be about 1000 F. The liquid cooling bath 19 is not essential and is mainly included in this operation to further reduce the temperature of the wire before it enters into subsequent treating steps for safety reasons.
The wire 1 is withdrawn from the liquid cooling bath 19 over sheaves 21 and introduced into a wire cleaning chamber 22. The chamber contains means for directing abrasive particles at high velocity at the wire 1 as it is passed between the sheaves 23 located within the chamber 22. In the drawing this is exemplified by centrifugal wheel 24 which has a feeding means 25 located thereon to introduce a supply of abrasive particles to the center of the wheel 24. The particles are then thrown down by centrifugal force of the vanes 26 situated radially along the wheel 24. A particularly suitable device for accomplishing this result is a Wheelabrator manufactured by the American Wheelabrator and Equipment Corporation, Mishawaka, Indiana. A detailed description of such devices is contained in the book Shot Peening, 4th edition, published in 1951 by the aforenamed company. The wire may be passed between the sheaves 23 as often as necessary to accomplish a thorough cleaning thereof. The cleaning chamber 22 used in this operation eliminates the need for chemical or solvent cleaning tanks with subsequent neutralization, drying, etc. Further, by the design described above the Wire is thoroughly cleaned while moving at an extremely high rate of speed, e.g., about 1000 feet per minute, all this being accomplished in a relatively small volume of space. More than one cleaning chamber may be used if desired to effect more thorough cleaning or to effect a reversal in the side of the wire exposed to the abrasive material should it be necessary.
As the wire is removed from the cleaning chamber 22 it is wound over sheave 27 and over sheave 28, the latter being mounted on a movable arm 29. As the wire 1 makes convolutions around sheave 27 and 28, a sensing device (not shown) is connected to arm 29 which senses variations in speed of the wire arriving at sheave 27 by the size of the convolutions produced around sheaves 27 and 28 (which is translated in terms of the angular movement of the arm 29). This sensing device then in turn controls and varies the speed of the motor 30. The motor 30 operates a worm gear 31 which is engaged wit-h the radial teeth 32 arranged around the periphery of the sleeve 33. Sheave 34 is attached to the sleeve 33 and winding arm extends radially from the sleeve 33 and is attached thereto, having sheave 36 at its outer extremity. The wire 1 passing around sheave 27 from sheave 28 is passed through the interior of sleeve 33 around sheaves 34 and 36. As the sleeve 33 and winding arm 35 rotate, the wire passing around sheave 36 is wound on stationary block 37 which has a tapered push ring flange 38. As
indicated before, the size of the convolutions around sheaves 27 and 28 will be a function of the speed of travel of the wire taken off. As the convolutions become larger, arm 29 will be lowered, this movement being sensed by the sensing means which then acts to increase the speed of motor 30. This in turn will increase the winding rate and thereby the take-off rate of the wire from sheave 27. The result will be smaller convolutions between sheaves 27 and 28 causing arm 29 to rise. When an excessive rise in arm 29 is sensed, the motor 30 will be slowed down. The result will be a carefully controlled winding rate in response to the rate of through-put of the wire perfecting the continuity of the entire operation. This winding operation continually produces and advances a nonrotating helical coil of wire along bars 39 which extend axially from the block 37 along its periphery. A suitable winding device and assembly showing the appropriate engagement between sleeve 33 and stationary block 38 is shown in the US. applications of Nye, Serial No. 67,350, filed November 4, 1960, now Patent No. 3,049,315, and Nye et al., Serial No. 75,965, filed December 15, 1960, now Patent No. 3,097,812. The helical coil of wire as it is advanced along bars 39 passes through coating chamber 40 which contains spray means 41 adapted to spray a solution of lime or borax which form a coating thereof on the wire. Drive means 42, which may be an endless belt or chain drawn by two sheaves as shown, are provided [along the interior of the coil to both advance the coil through the coating chamber and to slightly separate the convolutions of the coil to enable a complete coating thereof. The coating applied will operate as a protective surface to prevent oxidation during any interval between this and subsequent processing of the wire and further will serve to lubricate the wire for any subsequent drawing operation. Baking oven 43 is provided as a heating means to dry the coating. Any suitable heating means may be used, e.g., electrical coils, burners, hot air, steam heated coils, etc. The bars 39 taper downward at their extremities so that the coil of wire will fall therearound and collect on a suitable receptacle 44 located underneath. Since this is a continuous process, the receptacle 44 must be periodically changed when a sufiicient amount of wire is accumulated thereon.
The combination and method of this invention provide for patenting, cleaning, coating and winding of wire at extremely high speeds in one continuous operation. Further, all these things are accomplished with great precision and in a minimum volume of space.
Other modes of applying the principle of the invention may be employed, change being made as regards the details described, provided the features stated in any of the following claims or the equivalent of such be employed.
We therefore, particularly point out and distinctly claim as our invention:
1. A device for the continuous patenting and treatment of steel wire which comprises the following in sequence and in combination: a heating furnace, a rotary wire takeup block and drive means therefor operative to continuously, helically advance a coil of said wire into said furnace, cooling means having a rotary wire take-up block adapted to remove the wire from said furnace and to continuously, helically advance a coil of said wire, liquid quenching means comprising a tank adapted for continuous immersion of said wire therein, cleaning means comprising enclosures wherein abrasive material is directed at the wire surface while it is continuously moved therethrough, coiling means having a stationary horizontal block and a rotating winder in conjunction therewith, said coiling means adapted to continuously advance a helical coil of wire produced by said winder along said block, coating means wherein a protective coating material is sprayed on the wire as it continuously moves therethrough, heating means to dry said coating and receiving 5 means adapted to receive :said helical coil of wire so produced.
2. A device according to claim 1, wherein said block in said furnace is mounted for rotation vertically, having a tapered push-up flange at its base end wherein said wire is introduced tangentially along said flange on said block producing a helical coil which axially advances and said wire is removed tangentially near the upper end of said block, said furnace having a source of heat within a dome shaped structure around the upper end of said block.
3. A device according to claim 1, wherein said block in said cooling means is mounted vertically for rotation, said wire being tangentially introduced onto said block at its base and tangentially removed from said block at its upper end, said block being internally water cooled.
4. A device according to claim 1, wherein said extreme end of said horizontal block curves downward so that the coil produced continuously thereon advances therearound falling onto said receiving means.
5. A device according to claim 1, wherein tensioning means comprising pinch rolls is provided to act on said continuous wire prior to its introduction into said furnace.
6. A device according to claim 1, wherein scale removing means are provided ahead of said furnace, said scale removing means comprising a plurality of small diameter pulleys around which the wire is adapted to be wound whereby any scale on said wire is broken, and a die adapted to have the wire drawn therethrough whereby said broken scale is removed.
7. A device according to claim 1, wherein a wire storage block is provided ahead of said furnace, said block being vertically mounted for rotation and having a tapered push-up flange as its base whereby wire may be tangentially introduced along said flange and helically wound on said block and removed at the upper end of said block.
8. A method for the continuous patenting of steel wire which comprises the following sequence of steps in combination: continuously rotating and advancing said wire helically while applying a source of heat thereto, continuously cooling said wire, continuously cleaning said wire by directing free abrasive particles at the surface of said wire, continuously winding said wire into a non-rotating helical coil, continuously coating said wire by spraying its surface with a protective coating material, and continuously drying said coated wire.
9. A method according to claim 8, wherein any scale present on the surface of said wire is removed prior to said heating step.
10. A method according to claim 9, wherein said scale removal step comprises turning said wire around small diameter surfaces eifective to break said scale and scraping said broken scale from said wire.
References Cited in the file of this patent UNITED STATES PATENTS 686,921 Brown Nov. 19, 1901 2,045,392 Kientz June 23, 1936 2,196,600 Wean et al. Apr. 9, 1940 2,701,716 Erhardt Feb. 8, 1955 2,932,502 Rudd et al. Apr. 12, 1960 3,049,315 Nye Aug. 14, 1962 3,064,798 Nye et al Nov. 20, 1962 FOREIGN PATENTS 811,613 Great Britain Apr. 8, 1959 OTHER REFERENCES Pomp: Steel Wire, 2nd ed., pages 43 and 205, published by The Wire Industry Ltd., 33 Furnival St., London.