CA1072425A - Continuous rolled rod cooling and cleaning - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE

A system for treating continuously cast and rolled copper rod using a non-acid liquid treating composition for effecting removal of oxide scale present on the surface of the rod as it emerges from the rolling mill and for cooling the rod prior to coiling. One or more treating zones are provided between the rolling mill and the coiling machine. The treating composition is preferably an aqueous solution including one or more of aliphatic monohydroxy alcohols, polyhydroxy alcohols, ketones; and alkyl and alkanol primary amines, secondary amines, and tertiary amines; or mixtures thereof. The treating solution is recirculated and monitored with the pH being maintained at a value in excess of 7.

Description

~t7~S

BACKGROUND OF Tl-l~ INV~NTION
_ Field of the Invention This lnvention rel~tes to improved method and apparatus ~or treat~ng cont~nuouslr cast copper rod. More particularly this invention is directed to contr~lled cooling and cleaning of the cast rod prlor to being coiled and/or dra~n into fine wire, and in an improvement to Canadian Patent # 1,004,122, issued 25 January, 1977, for "continuous rolled rod cooling and cleaning".
Description of the Prior Art In the manufacture of continuous cast copper rod, ~he rod leaving the casting apparatus is generally immediately hot rolled. When exposed to the atmosphere the rod oxidizes -and accumulates surface scale comprising a mixture of cuprous ~red) and cupric ~black) oxides. As a practical matter, ~his - scale must be removed or reconverted to its metallic state, before the rod can be drawn into commercially acceptable wi~e.
Removal of the oxides is also necessary to prevent premature wear of the drawing dies and the like.
Heretofore, different approaches have been suggested for removing the oxide scale from the surface o~ copper-based products. It should be mentioned that the word "copper"
as used herein is meant to also include copper allo~s.
Exemplar~ of the approaches suggested for descaling are:
(1) mechanically removing the scale as by sanding, shaving or the like, ~2) acid cleaning ~or pickling), and ~3) ~apor reduction.
For example, U.S. Patent No. 3,623,532, whlch is assigned to t~e present applicant, discloses a system whereby acid pickling is used for descaling copper rod b~ immersing the rod in a dilute aqueous acid solution, e.g., sulfurlc acid, citric acid, after t~e cast rod lea~es the rolli~g Z- ?~

~ ~ 7 Z ~ 5 mill but before i~ reaches the coiler This disclosed pickling process utilizes the heat conta~ned in the rod to speed up the che~ical reaction. Under these condit~ons the copper oxides are re~oved from the surface by the combination of a phrsical- chemical process; t~at it, by popp~ng off due to the differences in thermal contraction of the oxides and the copper substrate, and partly b~ dissolving of oxides.
Usually, in less than one second, the rod has to be cleaned and cooled down from about 1000F. to about ambient tempera-tUTe. The used acid is then returned in the tank and pumped through the heat exchanger back to the injectors. To ma~n-tain optimal cleaning conditions, the pickling solution is continuously regenerated to maintain the copper content and the acid COncentTation at a predetermined le~el. This is accomplished by passing the used solution through the electroplating unit and periodically adding new acid to the s~stem.
The foregoing disclosed pickling process has been used with great success by the assignee of the present invention.
Ho~ever, in an effort to reduce operating costs necessitated by the use of acid resistant materials 9 to avoid ecological problems associated with waste acid disposal, and to produce a more consistentl~ better qualit~ product, an alternative approach to acid picking had to be found.
Other techniques which emplo~ one or more reducing gases or vapors to treat oxidized copper rod are disclosed in U.S. Patents No. 3,546,0Z9; 3,56Z,025; 3,620,853- and 3,659,8309 all issued ln the name of at leas~ C. J. Sn~der, and assigned to Anaconda Wire and Cable Co. In the aforemen-tioned ~atents, it is stated that oxide scale is remored by first exposing the rod to high temperature reducing gases or ~apors and therea~ter immedi~tely quenching the rod in a cooling bath prior to exposure to ~he atmosphere.

~ s Althouyh the gaseous reduction approach appears to have some advantages over acid pickling, certain disadvantages are believed to be inherent in such systems. For instance, the gases or vapors which are stated to be suitable for reducing copper rod are flammable, poisonous, or both, and there-fore requixe special handling ~o avoid explosion, asphyxiation, or the like. In addition thereto, oxygen-free atmospheres rnust be provided at elevated temperatures requiring special seals to totally confine the rod and reducing gases to prevent the entry of oxygen from the atmosphere as well as the escape of the confining gases to the atmosphere. Another disadvantage of vapor reducing systems resides in the fact that production rates are lower than with liquid contact systems.

STATEMENT OF THE INVENTION

In its broadest method aspects, the present invention is characterized by subjecting continuously cast and rolled hot copper rod, having an oxidized layer on its surface, to the following s-teps as it leaves the rolling mill and prior to being coiled:
a. passing said oxidized rolled rod at an elevated temperature in excess of about 900F. through at least one treating zone comprising an elongated open ended conduit for receiving a colder non-acid liquid composition therethrough;

b. introducing into said open ended conduit said non-acid liquid composition, said composition being a dilutè
aqueous composition including a reducing agent taken from the group consisting essentially of aliphatic monohydroxy alcohols, polyhydroxy alcohols, ketones; and alkyl and alkanol amines, secondary amines and tertiary amines; and mi~tures thexeof;

~72~5 c. contacting said oxidized rolled rod with said colder non-acid liquid composition and conv~rting the oxidized layer on said rod to metal while cooling said rod to a temperature below about 200F; and d. continuously recirculating said non-acid liquid composition and maintaining the pH of said recirculating liquid composition at a value in excess of 7.

As will be described in greaterdetail hereinafter, it is of paramount importance to the viability of the present method that the p~ of the treating solution is monitored, either con-tinuously or periodically, and adjusted to a pH value of above 7, preferably between about 3 and about 11, while in use. It has been unexpectedly determined that where the pH value falls below about 7, there results a decrease in the cleaning effectiveness of the treating solution and/or an increase in the dissolution rate of copper metal.
Accordingly, there is also provided in accordance wlth the invention novel apparakus for carrying out the afore-mentioned method which, in its broadest aspect, is characterized by:
a. means for providing a source of non-acid aqueous liquid composition at a p~ in excess oE about 7 for cooling and cleaning said rod;

b. at least one rod treatment zone downstream of said rolllng mill comprising an elongated open ended conduit for simultaneously receiving said rod and said non-acid aqueous liquid composition therethrough;

c. means for recirculating said liquid composition ~L~7Z~ZS

d. means for dixectly contacting said hot rod with said continuously recirculating liquid composition into said conduit whereby said hot roa is cooled and cleaned;

e. means for monitoring the pH of said recircula-ting liquid compcsition; and f. means for adding an alkali material to maintain the pH of said recirculating liquid composition above about 7.

By maintaining the -treating solution on the alkaline side of the pH range, the present method can be operated satis~
factorily over prolonged periods of time without damage to the equipment and at minimal opèrating cost. Moreover, the effectiveness of the treating solution is extended and therefore does not require frequent replacement or elaborate reconditioning operations.

' ' , ' , 1(1~24~5 In contradistinc~ion to the present method, conventional acid pickling requires stainless steel components or other expen-sive acid resisting materials. Additionally, the acid introduce~
su~stantial amounts of copper in~o the pickling solution which must be removed. Moreover, it was discovered that when a non~
acid treating solution is employed without maintaining close control of the pH, acids can be generated a~ a result of the oxidation of the solution. The acid formed will build up and remove copper from the rod. By maintaining close control of the treating solution o~ the present invention~ continuous xecondi-tioning using expensive electroplating equipment for removing excess copper from the solution is not required.
According to the present process, continuously cast copper rod is generally immediat01y passed through one or more rolling mills after leaving the casting machine while it i~ still in a ho~ condition, e.g., about 1500F. The rod leaves the rolling mill at a temperature of approximately lOOO~F. and is immediately directed ko a first zone where it i5 contacted with the non-acid treating solution according to this invention.
Whereas in the aforementioned conventional acid pickling system i~ was necessary to employ oil wiping or removal means, e.g., air blast, to avoid contaminating the pickling solution with lubricat~
ing oil, in the present invention the air wipe operation can be eliminated where the rod mill lubricant is compatible with he ~reating o tion o E tbe pr l;o_ invent on.

11~72~Z5 I`he oxiclii.ecl copper rocl leaving -the rolling mill is preferably at a -tempera-ture in excess of about 900F. If below 900F., a reduction in the cleaning efficiency is observed.
~`he hot rod is directed -through an elonga-ted condui-t on the order of 50 fee-t or more. One or more zones wi-th means ~or injecting the treating solu-tion into the conduit is provided.
Each zone has means for regulating the quantity of liquid treating solution being fed. In this way the rod temperature is controlled along its travel path until it exits at a tempera-ture below about 1500F. The colder non-acid liquid -treating composi-tion may be pumped through the cooling conduit in the same direction as the rod -travel, i.e., concurrently, at least in the first zone, subjecting the hottest portion o~ the rod to the colder treating solution which, due to the greater temperature differential between the rod and the treating liquid, increases ~he heat transfer rate and thereby accentuates the thermal stresses imposed on -the oxide scale. The pumping rate of the treating liquid is regulated to permit a moderate rise in the temperature of the liquid leaving the conduit, e.g., about 10F.
to about 160F. The treating zones which follow can be designed to direct pumped treating solu-tion concurrent to the rod travel as described for the first zone, or, countercurrent to the rod travel through the system, as will be described in greater de-tail hereinafter. In the first zone the treating compostion option-ally can be pumped through the cooling conduit coun-tercurrent to the rod travel through the system. In other embodiments contem-plated, one or morelof the treating zones are designed to contact the rod being treated with liquid pumped countercurrent to the ~7~ S
l~o~ trave~. (ombirlR~ivns o~ coun~ercurrent flows and concurrent f`lows in variouS treating zones may also be employed. Preferably the pumping rate of trea-ting composition for the f`irs-t treatment zone is regulated to effec-t lit-tle or no reduction within the f'irs-t zone of the temperature of the hot copper rod, or to ef'fect less of a temperature reduc-tion in the first treatment zone than in any of -the remaining treatment zones in which substantial cooling takes place. 'I`his is readily accomplished by regulating -the liquid flow to the first zone to roughly 10 percent of the entire liquid flow. The remaining zones introduce sufficien-t liquid treating solution so as to reduce the rod temperature to below about 200~. to preven-t reoxidation as it exi-ts from the cooling conduit. Thus, the operating parameters which can be varied to satisf`y any given production rate include; the temperature of the incoming treating solution, its flow rate, the number of zones provided, the length of cooling condui-t and the like. After the rod leaves one or more of the treating zones provided, it can be optionally water rinsed and waxed before being coiled. Either alternatively, or after the optional water rinse, lubriceous water-compatible waxing material optionally can be used in a water or suitable solvent solution or can be combined with the treating composition and used herewith withou-t adverse effects.
The non-acid treating composition according to this invention is formulated to provide both cleaning and cooling functions, and, if desired, can also include the lubriceous material, as aforementioned. More specifically, the treating composition is preferably an aqueous solution comprising at least one organic compound taken f'rom the group of aliphatic ~ 5 monohydroxy alcohols, polyhydroxy alcohols, ketones; and alkyl and alkanol pr~mary amines, secondary amines and tertiary amines;
and mixtures thereof. The pH of the solution is maintained above 7 and preferably between about 9-11. If required, the pH may be adjusted by the addition of predetermined quantities of alkali and alkali earth metal hydroxides, mineral and organic salts of alkali metal hydroxides, and the like. Sodium hydroxide, potas-sium hydroxide, calcium hydroxide, and sodium carbonate are exemplary usable pH regulating materials, although others may be substituted. For instance, basic organic compounds such as ammonia, amines can be added.
Although not en~irely undexstood, it is postulated that the mechanism ~or facilitating oxide removal from hot copper rod is based on the thermal oxidation o the alcohol group in the treatiny solution which results in the chemical reduction o CuO
and Cu2O to elemental copper on ~he rod surface. The oxidation reactions may proceed in one or two steps, dependin~ a~ the nature of the alcohol used. For purposes of illustration, where n-propyl alcohol is employed there occurs an oxidatiqn-reduction reaction in which the alcohol is oxidized to an ald~hyde and CuO
~or Cu2O~ is reduced to free copper, in thQ f~llowing manner:

H ~H
CH3 - CH2 - C - OH ~ CuO - ~ CH3 - CH2 - C~ ~ H2O C ( ) (n-propyl alcohol) --- (propionaldehyde) ! Thereafter, ~he aldehyde produced is oxidized still further to the~corresponding carboxylic acid while CuO is reduced to free copper. Thus, for

2~
" ~' ,o~l ~H3 ~ 2 ~ + Cuo ~ ~H3 C~12 - c~ + Cu (2) ~propionaldehyde) (propionic acid) Similar two-step reactions would be expected with other primary alcohols. However, in the case of secondary alcohols, e.g., isopropyl alcohol, oxidation of the secondary alcohol is completed in one step with acetone produced as a reaction product.
With alkanolamines, e.g., mono-, di-, triethanolamine, two-step oxidation reactions, similar to primary alcohols, occur Of course, each of the alcohol groups in the molecule underyoes a separate conversion. In addition tG their oxidation susceptibility, amines reduce the rate of reoxidation of the cleaned copper rod by fo~ming an electrostatic bond with the surface of the cleaned rod thereby shielding the rod from air and effectively retarding further oxidation of the rod. The pH of the amine containing treating solution should be above 7. If the p~
falls below 7, the amine forms a salt with the copper or with other metals which may be present in the water and may even precipitate from solution. Additionally, the concentration of amine is desirably below about 6 weight percent to keep the solution from foaming and preferably from about 1 to about 3 weight percent.
From the foregoing it will be clear that in the absence of providing pEI modifying or buffering agents, the oxidation rate would diminish as the concentration of acid increases. In addition to the slower reaction rate, the acid build-up would cause dissolution of the copper metal.
Both effects are undesirable and should be avoided. It was unexpectedly found that by maintaining the pH of the treating solution by above about 7, the oxidation reaction can be sustained at a high level oF effectiveness and without appreciable copper build-up in the solution ~.~72~'~S

The following general eqllati~n i~ belie~ed ~o apply:

2 [~ - C; 3 + Na2CO3 ~ 2 [R - C~ ~ ~ 2Na ~ CO2 r H2O

where R is alkyl group, preferably having 1-5 carbon atoms. By maintaining a pH above about 7 and preferably between 9 and 11, it was found that the treatin~ solution maintained it~ efficacy over a considerable period of time, e.g., six months or more.
In addition to the p~I modifying agent, the treating compo~ition of the present invention can ~esirably include con-ventional surface aGtive agen~s~ chela~ing agents, lub.ricants, and the like. The greater the rate o~ production, ~he gre~ter the pumping rate through each of the cooling condui-t~ ater soluble or emulsifiable waxes or the like can also be added to the treatin~ solution to protect the clean rod surfacs prior tc being coiled. Generally, the amount of wax which is added is low, i.e., on the order of 0.1% by weight of th~ composition.
Alternatively, waxing can be separately carried out after cleaning.
The temperature of the treating solution of tha present invention is maintained in the liquid state at from about 40F.
to about 200F~ As will be elaborated on hereinafter, the treating solution is continually recirculated and ~iltered.
Heat exchange means is provided in the recirculatory system to cool the treating solution pxior to its reintroduction into the treating zones.

. , , ~2~5 I`he licluid treating compos:it:ion employed in -the process of` the present invention preferably contains a major propor-tion of water, e.g., on -the order of 90 volurne percent or more. It will be appreciated -that the ra-tio of water to additives is not critical and can be varied.
The cleaning additives employed are preferabley water soluble. The aliphatic monohydroxy alcohols which are pre~erred have up to six carbon atoms. These include methanol, ethanol, n-propanol and the like. N-propanol has been found to give particularly good results alone, but expecially in combina-tion with polyhydroxy alcohols such as glycerol, glycol and the like.
The ratio of alipha-tic alcohol to polyhydroxy alcohol employed is not critical and can vary widely, e.g., from about 7:1 to about 1:1. The preferred polyhydroxy alcohols are those having two -to three hydroxyl groups such as ethylene glycol, propylene glycol, diethylene glycol and glycerol. Amongst the ketones which are useful in the treating compostion of the present invention it may be metnioned acetone, propanone, butanone and pentanone, alone, in combination with other ketones, or, in combination with one or more aliphatic monohydroxy alcohols or polyhydroxy alcohols such as glycerol, glycol and the like. The ratio of ketone toaliphatic monohydroxy alcohol and polyhydroxy alcohol is not critical and can be widely varied, as with the ratio of monohydroxy alcohol to polyhydroxy alcohol. The alkyl and alkanol primary, secondary and tertiary amines advantageously have up to six carbon atoms in each alkyl or alkanol group..
Preferably the alkyl or alkanol groups have from one to three carbon atoms. Most preferably the alkyl or alkanol groups have ~ ~ 7 ~ ~ ~ 5 two ca~bon atoms. The ratlo o~ amines to alco~ols employed is not CTitiCal and can var~ widely, e.g., from about 1:1 to about 1:7.
Clearly, the process acco~ding to this invention com- -prising non-ac~dic liquid treatment o~ oxidi~ed continuously cast and rolled copper rod r~elds substantial beneits over the conventional approaches earlier mentioned. In the present process, relatively inexpensi~e carbon s~eel can be utilized in contrast so the more expensive stainless steel required for acid treatment. Neither is it mandatory to emplo~ the elaborate alr wiping, rinsing or waxing equipment as formerl~ required. Nor is there any requirement for special high temperature seals, gas generating and quenching equipment necessitated b~ vapor phase reduction.
BRIEF DESCRIPTION OF THE DRAWINGS
- .
FIGURE 1 is a schematic flow diagram of one preferred system for treating continuous cas~ copper rod according to this invention and illustrates a three-zone system whereby the rod is cleaned and cooled in each of the zones.
FIGURE 2 is an elevational view, in section, illustrat-ing in detail a preferred first treatment zone for treating th0 copper Tod leaving the rolling mill wherein treating fluid is forced concurrent to the rod travel.
~IGURE 3 is an elevational view~ in section, of apparatus emplo~ed in conjunction with the first two treat-ment zones illustrating pressurized spray nozzles ~or spra~-ing treating fluid onto the rod lea~ingi-the first zone.
FIG~RE 4 is an eleYational view, in sect~on, of a second tTeatment zone through w~ich the copper rod passes prior to coiling~ illus~ra~ing treating fluid insroduced Into the rod conduit countercurrent to the direction of rod travel.

, , ~

1~7'h4~5 FIGURE 5 is an eleYat~onal view, ~n section, of a third ~reatment zone through which the copper rod passes prior to coillng and also illustra~ing a w~xing section prior to coil~ng.
Having descri~ed the invent~on in general terms, the follo~ing examples are set forth wi~h reference to the drawings to more particularl~ illustrate the invention. The examples are not intended to be limiting.

Aqueous non-acid treating solution was prepared by mixing one or more of the following ingredients in the proportion~ shown below:

~olume %
Ingredient ~(2)- (3) (4) ~5) (6) (7) Monohydroxy alcohol ethanol 24.0 15.0 n-propyl alcohol 41.8 20.0 isopropyl alcollol 28 . 3 butanol 5 polyhydroxy- alcohol glycerol 10.0 ethylene glycol 5.0 ketones 30.0 amine$
di-ethanolamine 5.0 triethanolamine 2.6 12.0 3.0 2.0 5Ø
~ater 69.1 95 46.2 73.0 70.0 73.0 65.0 The pH o~ the aboYe treatlng soluti~n~ was adjusted to about 9.5 by the addition of sodium carbonate. Calcium i~

~72425 acetate was added as needed as a foam suppressant.
The non-acid treating solutions shown above, i con-centrated, a~e ~urther diluted with water to yleld a concen-tration of less than about la% by volume and pre~era~ly between 2-6% by volume.
EXAMPL~ 2 The treating solution prepared in accordance with Example 1 was introduced înto tank 30 of Figure 1 o~ the drawing and was continuously recirculated throughout the system at a rate of about 300 gpm. The operating conditions under steady state conditions were as follows:
Production rate: 20 tons/hr.
Rod size after rolling: 5/16 inch Temperature of treating solution O
at inlet of 1st treating zone: 100 ~.
Temperature of treating solution O
at outlet of final treating zone: 120 F.
Temperature of rod at inlet of 1st treating zone: llC0F.
Velocity of treating solution in 1st treating zone: 25 gpm.
Periodic analysis of the treating solu~ion being ?
recirculated indicated a copper con~ent build-up ~o be on the order of about 40 ppm, far less than experienced with acid pickling. The oxide scale was continuall~ remo~ed b~ f~lter means provided in the pump d~scharge. Per~odically, make-up solution was added (5 gal./hr.) *o the s~ste~.
The copper rod being treated in the manner described hereinbe~ore ~as found to be uniformly free of ox~de scale.
One o~ the important ad~antages of this invention resides in the abil~t~ to operate at much higher production rates than the suggested ~apor phase des~aling techniques and without the inherent dlsad~antages assoclated with ~ot~ said pickling and/or ~apor phase reduction~

'' ~ .

~L~7~S

DESCRIPTI ON OF A PREFERRED EMBODIMENT
Refer~ing now in detail to the drawings, wherein like numeral5 indicate like elements throughou~ the several views, Figure 1 schematically depicts a continuous castlng system 10 wherein molten metal is formed into cast bar 12 in casting machine 11. The bar is rolled in rolling mill 13 which reduces the cross-sectional area of ~he bar and at the same time increases its length to ~orm cast rod 14. The cast rod 14 is therea~ter su~jected to the non-acidic treatment accord-ing to this invention ~e being d~rected sequentiall~ from rolling mill 13 into the first treating zone represented by reference numerals 15-17. The second treatment zone, represented b~ numerals 17-19, further processes rod 14. The third treatment zone, represented by numerals 19-21, receives rod 14 for still further processing. Thereafter, rod 14 is optionally rinsed and/or waxed in apparatus 21 and directed to pinch rolls 22, rod gu~de mechanism 23 and coiler 24.
Bet~een the first and second treatment zones a pressurized spray treatment is included (Fig. 2).
As the rod 14 moves towards coiler 24, treating solution from tank 30 is continuously recirculated through the system 10. Treating solution is pumped from tank 30 via conduit 32 by pump 31 to water cooled heat exchanger 33 via conduit 34. The treating solution is directed through conduit 35 to each of the treating zones 15-17, 17-19, 19-21 via conduits 36-39, respectively. Return conduits 40, 61 carry the treating solution back to tank 30 for further recircula-tion.
It should be understood that the s~stem outlined herein-above merel~ represents one prefer~ed embodi~ent-wllerein three ~ ~ !

~7'~5 zones ara employed for directly contacting the hot rod 14 with the non-acid liquid treating composition of the present invention.
In this instance, the treating fluid passes concurrent to the rod travel in the first zone 15-17 and countercurrent to the rod travel in the second zone 17-19 and third zone 19-21. The flow in the ~irst zone i6 regulated to provide laminar flow so as to prolong the;Pffectiveness of the oxidation-reduction reaction between the oxidiza~le treating agents and the oxidized copper.
However, all three zones can be readily designed to force liquid treating fluid countercurrent to the rod travel. Similarly, each of the zones can be altered so that the fluid passes either countercurrent or concurrent to the rod travel. Moreover, this system can be readily modified to operate with two zones and even one zone wherein cleaning, cooling and coating can be simultane-ously effected. By-way of example, zone 15-17 can be utilized for cleaning and partial cooling and zone 17-19 for cooling and waxing. To implement these variations, it is only necessary to reverse, add or delete one or more of the easily separable com-ponents as will be described in more detail hereinbelow. This invention should not be construed as being limited to three zones since additional zones can be added without adverse effects and in fact it may be necessary to add two zones substan~ially iden-tical to the irst zone, in series. Although a totally counter-flow system, as described,for example,in the earlier-mentioned acid pickling system of U~S. 3,623,532, can be employed~
advantageously the present system uses first concurrent flow and thereafter countercurrent flow. A greater temperature differen-tial ifi obtained as the hot rod en~ers ~he cooling conduit where _ 18 _ !

, .", , .,; , . . .

107'~25 col~er liquid is impinged in concurrent flow. This initial shoc~ aids in fracturing the oxide scale on the rod surace.
Referring now to Figure 2 which i5 a detailed section of apparatus utilized in the first treatlng zone 15-17 through which rod 14 passes for cooling and cleaning, uni~ 15 comprise~
a housing 50 with entrance wall 51 which abuts the housing of rolling mill 13, e~it wall 52 and a baffle plate 53, each having aligned apertures for receiving the rod 14 from the rolling mill 13. Air nozzle 59 which can be used with air, steam or other 1~ gases is positioned in and extends through the opening of entrance wall 51. Air nozzle 59 surrounds the path P through which the rod from rolling mill 13 is to pass. Aix nozzle 59 includes cylindri~
cal housing located in abutmen~ with entrance wall 51 and small diameter threaded portion 62 protrudes through the opening of entrance wall 51 into the housing of rolling mill 13. Nut 64 engages the external threads of thxeaded portion 62 to hold air nozzle 59 in place. Cylindrical housing 61 defines opening 65 which is placed in alignment with the path of travel P of the rod, and opening 65 is counterbored at 66. Counterbore 66 and opening 65 merge together by means of tapered portion 68. ~ir supply pipe 69 communicates with counterbore 66 ~hrough port 70 in air nozzle housing 61. No~zle insert 71 is threaded into counterbore 66 and defines rod opening 72 which is in alignment with path P and rod opening 65 o air nozzle housing 61v The . inner end of nozzle 71 defines tapered portion 74 which is siæed and shaped to mate with tapered portion 68 of air nozzle housing 61. The diameter of nozzle insert 71 is sub~antially fPqual to the diameter o counterbore 66 of air nozzle 61 at their respec tiY~ threaded portions, and nozzle insert 71 is reduced in its ~ -19 ~ 7;~4~5 out.side diameter at 75, between tapexed portion 74 and threaded por~ion 76. Thu~, an annular supply chamber 78 is defined between no~zle insert 71 and air nozzle housing 61, which communicates with air supply pipe 69. Flange 79 extends radially outwardly ~rom the reduced-diameter portion of nozzle insert 71 into annular supply chamber 78, and flange 79 is notched at spaced interval6 around its periphery. Flange 79 functions as a control flange ancl is normally posi~ioned in the vicinity of port 70 of air noz:zle housing 61. When nozzle insert 71 is moved to its fullest ¦extent into air nozzle housing 61, flange 79 w.ill move beyond port 70, and restrict the flow of fluid from air supply pipe 69.
Also, the tapered portion 74 of nozzle insert 71 will he placed closely adjacent the tapered portion 68 of air nozzle housing 61, which also functions to limit thQ flow of fluid from annular supply chamber 78 into rod opening 65 of air nozzle 61. Thus, when high-pressure air, steam or other gas is flowin~ through air supply pipe 69 from the air supply, its volume of flow and flow velocity into rod opening 65 can be controlled by moving nozzle insert 71 inwardly or outwardly of air nozzle housing 61.
Once a desired setting has been attained, locknut B0 can he ~:
rotated on the threads of nozzle insert 71 and forced against air nozzle housing 61 to lock nozzle insert 71 in place.
Thus, it is seen that air nozzle 59 functions to mi:nimize the amount o~ lubricant carried by the rod 14 beyond the rolling mill 13 by impinging an annular flow of air generally in a direction opposite to the movement of rod 14. As earlier mantioned, this air wipe can be deleted, if desired, where the treating composition is compatible with the lubricating oil, as i~ the case here.

~ 10'724~S

As the rod 14 moves along path P and pas~es from air nozzle 59 through housing 50, it will be guided by baffle plate 53 wh.ich defines an aperture which surrounds path P. Baffle plat~ 5 includes a guide socket 86 located in the aperture defining an annular converging opening 88 ~or guiding the lead end of the rod 14 initially entering the cooling conduit 16 from air no~zle 59 along path P .
The bottom wall 89 of housing 50 includes a drain pipe 90 which functions to carry away any oil treating fluid which mayaccumulate therein.
At the exit wall 52 of the housing S0 there is disposed injector means for continuously introducing the treating solution of the present invention into the cooling conduit 16.
Injector means includes an injector nozzle 100 connected to exit wall 52 and includes nozzle housing 101, nozzle adapter 102, and nozzle insert 104. Adapter 102 and nozzle insert 104 each define rod openings 105 and 106 which are in alignment with rod path P. Rod opening 105 of adap~er 102 flares into tapered portion 109 while the outer surface of insert 104 converges into tapered poxtion 108 which is sized and shaped to mate with tapered portion 109. Housing 101 defines threaded bore 110, into which insert 104 is threaded, and the counterbore 111. The annular space between insert 104 and counterbore 111 comprises annular supply chamber 112, and port 11~ is connected to supply conduit 36 and opens into annular supply chamber 112. The supply conduit 36 functions to communica~e a source of high-pre~sure trea~ing fluid wi~h annular supply chamber 112, and the treatlng'~olution flowing to annular supply chamber 112 1~7Z4~5 flows between tapered portions 108 and 109 of adapter 102 and . insert 1~4, in~o rod opeining 105 of adaptex 102~ and along path : P of the rod 14. The direct.ion of flow of the treating solution : flowing through the tapered annular o~ifi~e 116 formed by tapered portions 10~ and 109 is general~y along the length of path P into cooling conduit 16 which functions to create a flow of treating solution through rod conduit 16 along the length of the rod 14 in the same dixection as the movement of the rod.
The conduit 16 is main~ained in a substantially filled condition ,` 10 while the rod is passing therethrough~
Referring now to Figure 3 which is a detailed sectio~al view of apparatus 17 positioned between the first treatment zone 15-17 and the second treatment zone 17-19, there is shown a . housiny 120 provi:ded with aligned apertures formed in entrance t" wall 122 and exit wall 124, a baffle plate 125 substantially .~ identical to baffle plate 53 of Figure 2, around rod path P.
Spray nozzles 126, 128 positioned above rod path P on opposite sides of baffle plate 125 are provided to direct a stream of high pressure treating solution onto the rod 14 passing therebeneath. ., ~` 20 The function of the spray section is to dislodge oxide scale loosened from the surface of the rod 14 after ~eing thermally ~:
shocked in the first treatme~t zone 15-17. The spray emitted by noz~les 126, 128 also directs the entering treating solution from conduits 16, 18 towards the opening 130 located in the ~o~om wall 132 of the housing 120 for return to tank 30 (Figure 1) via .~; conduit 40. By partially separating the oppositely entering treating solution the tendency to foam is thereby minimized. V~t me~ns 1 , 136 communicating with the intericr o~ the ùousing 120 22 _ ..

~ 72~Z5 is provided on the top wall 138. The baffle plate 125 depends from the top w~ll 138 of housing 120 and includes a guide socket 139 located in the aperture defining an annular converging opening 140 for initially guiding the lead end o:E the roll 12~ a~ before mention~d.
~ reating solution entering apparatus 17 ~ia conduit 1 originates in apparatus 19 as best seen in Figure 4. Thus, for purposes of explanation, as in the case of first tre~tment zone 15-17, ~he second treatment 7.one is depicted by reference numerals 17-19 and includes the elements 17, 18, 19. Apparatus 19 comprises housing 150 provided with aligned apertuxes formed in entrance wall 152 and exit wall 154. Injector nozzle 160 is connected to the entrance wall 152 and is identical to injector 100 of Figure 2, except that it is positioned so as to inject treating solution into cooling co~duit 18 countercurrent to the direction of travel of rod 14. Supply conduit communicates with conduit 38 to provide the trea~ing solution to injector 160. A
flow accelerator 170 is connected to exit wall 154 of the housing 150 and includes housing 171 and nozæle spool 172. Nozzle spool 172 extends through the opening of exit wall 154 and defines opening 173 along its length, which is in alignment with rod path PO Annular groove 174 is cut in the ~xternal surface of nozzle spool 172, and a plurality of apertures 175 extend from annular yroove 174 toward rod opening 173, at an angle extending toward the housing 150. Flow accelerator housing 171 surrounds an~ular opening 174, and an annular supply chamber 176 is defined ~etween housin~ 171 and nozzle spool 172. Supply conduit 178 communicates with port 179 which opens into annular supply 23 ~

- 111i7Z'~Z5 chamber 176 and fl~ws through apertures 175 into rod opening 173.
Apertures 175 are arranged so that the velocity of ~he ~reating solution flowing into rod opening 173 is in the dir~ction of housing 150, which induces a fluid flow through rod opening 173 to~ard housing 150. Thus, liquid in conduit 20 will be further il induced to flow toward housing 150.
l Drain conduit 180 is connected to housing 150 through ¦ bottom wall 182. Vent opening 184 is connected to housing 150 ¦ through top wall 186. Thus, any treating fluid received in hous-¦ ing 150 from flow accelerator 170 or from cooling conduit 20 will I be drained away via drain 180. Similarly, any gases present in I housing 150 can be exhausted through the vent 184. It should be i mentioned that under normal operating conditions the rod 14 leaves the second treatment zone 17-19 in a substantially clean ¦~ condition at a temperature below which any substantial reoxidation of the rod can occur upon exiting the final treatment zone, e.g., ¦ 150F. A third treatment zone substantially identical to the ¦ se~ond treatment zone is optionally provided fvr increased production rates. For purposes of completeness, the third zone ~ can be a combined treating-rinsing device substantially as shown in earlier-mentioned commonly assigned U S Patent 3,623,532 (Figure 5), modified to receive the non-acid treating solution according to this invention, or, as shown in Figure 5 can be i` combined with a waxing applicator. Referring now to Figure 5, apparatus 21 includes housing 200 divided by baffles 201, 202.
Entrance wall 203, exit wall 204 and baffles each define aligned openinys about rod path P, sg that the rod 14 can pass through the houaing Gu~de socksts 205, 206 ~upported by baffle 202 and exit ~t7~ 5 ,' wall 204 gnide the leading end o~ the rod 14 along path P.
Injector 2~7 posit~oned in entrance wall 203 ls sim~lar to injector 160 of ~i~ure 4, and t~ea~ing solution rom supply 3D
enters the injector 207 via conduit 39 under pressure and co~-municates with conduit 20 through ~hich the rod 14 passes.
The direction o flow of t~e treating fluid is counteTcurrent to the rod tra~el. rt will be recalled, however, that this feature can be modified to dlrect the fluid concurrent to the rod travel.
A ~axing nozzle 20~ is po~i~ioned in baffle 201 down-strea~ of ~njector 2Q7. Waxing nozzle 208 is simllar to air nozzle 59 of Figure 2. Condui~ 209 communica~es with a source of wax (not shown) to supply wax under pressure to waxing nozzle 208. The surface of the rod 14 is thereby coated as the rod passes therethroug~. A drain line 210 at the bottom wall 211 of housing 200 returns unused wax to the supply ~not shown~. If desired, an air nozzle similar to ~he air nozzle 59 of Figure 2 can be pos~tioned immcdiately thereafter the waxing step to wipe excess wax from the rod 14 and to drr the rod. Ho~ever, this additional feature can be d~spensed with since the rod retains su~fic~ent latent heat to self-dr~ after coiling. ~ent 213 connected to top wall 212 of housing 200 functions to exhaust gases from the housing 200 to t~e atmosphere. The equipment do~nstream of the combined treating-waxlng de~ice includes p~nch roll$
22, rod guide mechanism 23 and coiler 24, schematicall~
shown in Figure 1 of the drawing. These devices are described in detail in U.S.A. Patent 3,623,S32. It ~hould be mentioned~
that the ~axing applicator can be eliminated where the treating composit~on of this invention is formulated wi~h a ~i compati~le lu~riceous mater~al ~hlch minimizes ~urther '- oxidation and unctions as a lubr~cant for subsequent ~ire ~ z~s drawlng operations. ~or add~tional protection, a separate ~axing step can ~e employed, i~ desired.
It should ~e appreciated that the present invention is not to he construed as belng limited ~ the lllustrati~e embodiments. rt ~s possible to produce still other embodi-ments withou~ departing from the inventi~e concep~s herein disclosed, Such embodiments are within ~he ability of one , .
skilled in the art.

, :

Claims (20)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A method for cleaning oxidized roller copper rod emerging from a continuous casting machine, and a rolling mill downstream of said casting machine, said roller copper rod having an oxidized layer on its surface as it emerges from the rolling mill, characterized by the steps of:
(a) passing said oxidized rolled rod at an elevated temperature in excess of about 900°F. through a first treating zone comprising an elongated open ended conduit for receiving a colder non-acid liquid composition therethrough;
(b) introducing into said open ended conduit said non-acid liquid composition, said composition being a dilute aqueous composition including a reducing agent taken from the group consisting essentially of aliphatic monohydroxy alcohols, polyhydroxy alcohols, ketones; and alkyl and alkanol amines, secondary amines and tertiary amines; and mixtures thereof;
(c) contacting said oxidized rolled rod with said colder non-acid liquid composition and converting the oxidized layer on said rod to metal while cooling said rod to a temperature below about 200°F; and (d) continuously recirculating said non-acid liquid composition and maintaining the pH of said recirculating liquid composition at a value in excess of 7.

2. The method according to claim 1 characterized by the fact that said aliphatic monohydroxy alcohols have from one to six carbon atoms, said alkyl and alkanol primary, second-ary and tertiary amines have up to six carbon atoms in the alkyl and alkanol groups, said polyhydroxy alcohol has two to three hydroxyl groups, said ketone is selected from the group consisting essentially of acetone, propanone, butanone and pentanone.

3. The method according to any of claim 1 wherein said liquid composition includes a mixture of n-propanol and glycerol.

4. The method according to any of claim 2 wherein said liquid composition includes a mixture of n-propanol and glycerol.

5. The method according to any of claims 1 and 2 wherein said liquid composition includes a mixture of n-propanol and triethanolamine.

6. The method according to claim 1, 2 or 3 wherein said liquid composition is maintained at a pH range of between 9 and 11, and said liquid composition includes at least 90 volume percent water, the remainder being one or more of said reducing agents with or without additives.

7. The method according to claim 1, 2 or 3 wherein the recirculated liquid composition is at least periodically tested and alkali is added to maintain the pH value at between 9 and 11.

8. The method according to claim 1, 2 or 3 wherein the liquid composition is regulated through said open ended conduit in a first zone at a rate which yields laminar flow thereby prolonging the initial effect of said reducing agent on said rolled rod.

9. The method according to claim 1, 2 or 3 wherein the liquid composition is passed concurrent or countercurrent to the direction of rod travel in said first zone.

10. The method according to claim 1, 2 or 3 including the steps of providing a second treatment zone downstream of said first zone, passing said rod therethrough and contacting said rod with said liquid composition flowing concurrent or countercurrent to the direction of rod travel.

11. The method according to claim 1, 2 or 3 including the steps of providing a second treatment zone downstream of said first zone, a third treating zone downstream of said second zone, passing said rod therethrough, and contacting said rod with said liquid composition flowing current or concurrent to the direction of rod travel.

12. The method according to claim 1, 2 and 3 wherein said liquid composition flowing in said first zone is about 10 percent of the total liquid composition introduced, the remaining liquid composition being provided in one or more subsequent zones.

13. The method according to claim 1, 2 or 3 including the steps of providing a second treatment zone downstream of said first zone, a third treating zone downstream of said second zone, passing said rod therethrough, and con-tacting said rod with said liquid composition flowing concurrent or countercurrent to the direction of rod travel, wherein said liquid composition flowing in said first zone is about 10% of the total liquid composition introduced, the remaining liquid composition being provided in one or more subsequent zones.

14. Apparatus, particularly suited for carrying out the method according to claim 1, for cleaning oxidized rolled cast copper rod having an oxidized layer on its surface as it emerges hot from a continuous casing machine and rolling mill, characterized by:
(a) means for providing a source of non-acid aqueous liquid composition at a pH in excess of about 7 and cooling and cleaning said rod;
(b) at least one rod treatment zone downstream of said rolling mill comprising an elongated open ended conduit for simultaneously receiving said rod and said non-acid aqueous liquid composition therethrough;
(c) means for recirculating said liquid composition;
(d) means for directly contacting said hot rod with said continuously recirculating liquid composition into said conduit whereby said hot rod is cooled and cleaned;
(e) means for monitoring the pH of said recirculating liquid composition; and (f) means for adding an alkali material to maintain the pH of said recirculating liquid composition above about 7.

15. The apparatus according to claim 14 characterized in that said means for directly contacting said liquid composition with said hot rod in said conduit comprises an injector with means for controlling the quantity of liquid injected into said conduit.

16. The apparatus according to claim 14 characterized by an injector being positioned to direct said liquid com-position in a direction concurrent or countercurrent to the rod travel.

17. The apparatus according to claim 14, 15 or 16 characterized by a plurality of treating zones, an injector including a control valve which permits about 10 percent of the entire liquid composition to pass therethrough in a first zone.

18. The apparatus according to claim 14, 15 or 16 characterized by a second treatment zone, including means for continuously introducing said liquid composition into said conduit through which the rod passes in a direction concurrent or countercurrent to the rod travel.

19. The apparatus according to claim 14, 15 or 16 characterized by a second zone and a third treatment zone for said rod leaving said second zone, including means for continously introducing said liquid composition into said conduit through which the rod passes in a direction con-current or countercurrent to the rod travel.

20. The apparatus according to claim 14, 15 or 16 characterized by means for rinsing said rod with water and means for coating said rod with a lubriceous material after treatment in its last treatment zone and before the rod is coiled.