US2330038A - Method and means of disintegrating metal into abrasive material - Google Patents

Description

J. F. ERVlN Sept 21, 1943.

METHOD AND MEANS OF DISINTEGRAIING METAL INTO ABRASIVE MATERIAL 2 Sheets-Sheet. 1

Filed Oct. 14, 1%40 J. F. ERVIN Sept. 21, 1943.

METHOD AND MEANS 0F DISINTEGRATING- METAL INTO ABRASIVE' MATERIAL Filed Oct. 14, 1940 2 Sheets-Sheet 2' Patented sept. 21, 1943 UNITED STATES PATENT OFFICE METHOD AND MEANS OF DISINTEGRATING METAL INTO ABRASIVE MATERIAL John F. Ervin; Ann Arbor, Mich. Application October 14, 1940, Serial No. 361,158

Claims. (CI. 83-91) This invention .relates to improvements in methods and means of shotting or disintegrating metal in the production of metal abrasive or the like discrete material, having reference to practice of the character described for example in my priorU. S. Patent No. 2,159,433 of May 23, 1939 upon which it is a further development- The shotting of metal-sometimes called atomizing-is an operation involving certain technical difliculties arising from its nature and entirelysatisfactory results have not yet been attained, especially when dealing with special metals or alloys in attempt to produce especially high quality abrasives. One of the principal difficulties is to secure a uniform shotting or comminution of the metal, so as to have the bulk of it formed into globules or spheroids of the same desired size and avoid the substantial loss or wastage from a breaking up into irregular fragment pieces and into mere pulverulent or dust. Another principal difllculty is to obtain a perfect globular or spherical formation of the shotted particles of metal broken up into discrete form, so as to avoid the loss of imperfect formations. Due to the forces existent in the break up of a metal into divided particles, it is hard to exercise any control upon the action taking place and what control is possible must be attained or imposed largely through the means and operative conditions provided for effecting the action.

An objectof the invention is to provide an improved method and means of shotting metal, by which to attain a definite uniformity in size of the divided or comminute particles into which the same is broken up and to materially reduce the quantity and consequent los of irregular disintegration with substantial amounts of waste fragment and mere pulverant.

Another object is to provide an improved method and means of the kind stated, by which to obtain a true spherical formation of the'divided metal-particles and to substantially reduce if not to wholly eliminate the possibility of imperfect formations necessary to be separated out, with consequent loss.

A further object is to provide such a method and means by which to control within substantial limits the size of the shotting or breaking of the metal into granular particles or globules.

The invention will be more particularly described by the following specification with reference to the accompanying drawings, illustrating the same in twoexemplary working embodiments of alternative or diiferent modification plan represented in elementary form.

In said drawings:

Fig. 1 is a side elevation view in part section of one embodiment;

Fig. 2 is a top plan view of Fig. 1, omitting the receptacle member thereabove;

Fig. 3 is a detail front end view looking from the left of Fig. 2; I

Fig. 4 is a side elevation view in part section of the other embodiment:

Fig. 5 is a top plan view of Fig. 4, omitting the upper receptacle member;

Fig. 6 is a detail view taken on the line 6-6 of Fig. 4; and

Fig. 7 is a broken off view of modification.

, The claimed invention consists fundamentally in discharging a molten stream of the metal into the angle between two convergently meeting streams of liquid, said liquid streams being projected under regulated variable pressure force and in the form of a closely spaced series of fine streams or jets. j i j In the embodiment or arrangement'of Figs. 1

illustrating a detail to 3, one of the liquid streams, designated as 10, I

is employed as the main stream and is projected in a horizontal plane. The other stream ll constitutes the secondary stream and is projectedln a substantially vertical plane. The metal in a molten stream I2 is discharged into the angle formed between these two converging streams, in this instance onto the main stream slightly in advance of the secondary streams contact therewith. This secondary stream is adapted to be swung toward and away from the point of the metal stream contact with said main stream, thereby increasing or decreasing the angle between the two liquid streams, so as to quicken or delay its action upon the metal stream.

The two liquid streams are projected in a closely spaced series of fine streams or jet Hi and II respectively, the former through nozzle orifices I3 in a nozzle head I3 and the latter through nozzle orifices M in a nozzle head It. The main stream jets HI collectively form a relatively thick bodied spout of the liquid by arrangement of the nozzle holes l3 in tiers one above another (see Fig. 3) and will advantageously give a cross-sectionally trough shape to said'spout or stream by arranging the rows in the form of a V or .U as shown in the front detail view. The secondary that the two liquid streams have been represented in parallel shafts to indicate their composition by mult ple individual jets or separate fine streams spaced clcsely together.

The main stream I is projected through said nozzle head l3 carried on the end of a nozzle arm or tube IS, the latter being swivel connected with a supply pipe l6 through which the liquid is supplied under pressure from a suitable supply source (not shown) and having a control valve ll therein for regulating the force of the supply therethrough. The swivel connection with said supply pipe is advantageously of a compound or universal type so as to permit its swing in.both vertical and horizontal planes, although a swivel to swing in a vertical plane only will in most cases be suficient. The connection for vertical swing may be provided for example by a nipple l8 carried by a collar l8 rotatable on the supply pipe I6 so as to swivel the nozzle upon the axis of saidsupply pipe, while the connection for horizontal swing may be provided for example by a neckor T-coupling l9 fitting into and rotatable within said nipple so as to swivel the nozzle upon the axis of said nipple see the arrows indicating the nozzle swing in the two planes). The forward end ofthe nozzle is supported by a stirrup bar 20 adjustable up and down by a worm wheel 2| working on its suspension shaft 20 from a suitable fixture'bracket. Thus, it will be firmly sup-' ported in any position to which it is set.

The secondary stream ll is'projected through said nozzle head [4 comprising or connected to the end of a supply pipe (not shown) through which the liquid is supplied under pressure from a suitable source (not shown). This nozzle I4 is" rotatable in opposite directionsupon its own axis, as indicated by'the arrows, so as to swing the said secondary stream toward and away from' the point of metal stream contact with the main v j liquid stream as previously stated. Suitable provision is of course made to hold said nozzle in the position to which it is set or adjusted.

Themetalstream is supplied through a vat 22 located above the main'stream level and having a trough or nozzle 23 from which the molten metal supplied from said vat is discharged onto the main' liquid stream as stated. This molten metal, stream may be discharged or projected under pressure rather than by gravity alone. if so desired, by provision made therefor within the vat and said drain or nozzle 23 of course determines the size or thickness of the stream which is projected.

Referring to Fig. 3, an additional nozzle i3 is represented in dotted lines at the left of the single nozzle shown in full lines. This representation is made to indicate how a series of corresponding nozzles might be laid out in horizontal adjacency either to widen the'breadth of the main stream or to provide a series'of main streams to act upon a corresponding series of metal streams caused to discharge from the vat 22; In the event of such addition or provision of added nozzles, the secondary stream l i may be correspondingly widened by simply adding an additional numberof nozzle or fices Hi to the line ,thereofQ Such a modification will be obvious in the light of what has been heretofore described and will require no further description or amplification.

In the embodiment or arrangement of Figs. 4 to 6, thetwo liquid'streams, designated I00 and lll,.are projected in oppositely inclined planes toward a common center. The molten metal stream I2 is in this instance discharged directly into the vortex of these meeting streams so as to be acted upon alike or at the same time by both.

The said two liquid streams are projected from parallel nozzle heads (33 and I44 through nozzle apertures I33 and HM in a closely spaced series of fine streams or jets I00 and l I I respectively, as in the first described embodiment. Said nozzle apertures are formed in the nbzzle heads in a straight longitudinal line in this instance, although they might be arranged in staggered relation or in staggered rows as represented in Fig. '7. In other words, the body thickness of the treams will be determined not only by the size and closeness of said apertures, but by the number of rows in which they are formed in the said nozzle heads. The primary consideration is to make them form or produce streams of sufiicient thickness to act with proper force and to the proper extent upon the molten metal.

Said nozzle heads I33 and I44 are mounted to swing parallel to each other in a vertical plane at the end of the nozzle arm or tube l5, as indicated by the arrows, in order to change the angle of their action upon the metal stream, as well as the distance to be traversed by the metal stream before contacting the same. In other words, said nozzle heads are arranged to swing up and down substantially upon the are described by the metal stream from its projection point, thereby quickening or delaying the latters contact with the liquid streams. This swinging or swivel connection is effected as by a pipe piece 24 rotatable within a T-coupling 25 on the nozzle tube end and to which said nozzle heads are connected by elbows 26. Said nozzle heads are also individually turnable upon their own axes as indicated in Fig. 6, thereby permitting them to be adjusted so as to change the angle at which the two liquid streams are brought together. Referring to Fig. 6, the angle at which the two streams are in this instance brought together is indicated in full lines and by the letter (1. Other. angles, both greater and-smaller, at which they may be adjusted to meet are indicated in dotted lines by the letters I) and 0. Thus, the depth of the vortex or angle into which the metal stream is discharged against the liquid streams may be regulated according to wish or result requirements. Ordinarily. the best angle of the liquid streams meeting will be approximately that indicated in the full lines in this and the other views, as otherwise the action or agitation between the two liquid streams themselves may be too great or too little. Said nozzle arm or tube IS in this instance supplies both of the parallel nozzle heads and is connected with a suitable'source of liquid supply under pressure as before described. That is to say, said nozzle arm or tube is connected with the supply pipe l6 and is provided with a control valve I! for regulating the force of the liquid supply therethrough. In this instance, only the neck or T-coupling I9 is shown in its connection with the supply pipe l6, but it will be understood that the connection is or will be the same as described in the first embodiment, so that said nozzle pipe may be adjustably swung in both vertical and horizontal planes. Also, as in the first instance, said pipe is supported by an adjustable stirrup bar 20 at its forward end. The metal stream is discharged as before from the vat 22 and trough or nozzle 23.

In operation, the liquid streams are prol'ected under pressure ranging fromapproximately 30 to pounds per square inch, 1;." ring them a through or between" which the. broken particle's?v must pass While being carried forwardly-by the: force of thestreamiflow. In the case of the first embodiment, the mainstream effects: anminer break-up which is followed" by. the secondary stream adding to its effect and completing; what disintegration mayi-not initially take place; In" the case of thesecondembodiment; the come bined ,liquid streams acting'fuponfthe;metal in the vortex of their meeting producethe samei efiect, except that it isv a" little-moreuniiorm'and causes a somewhat finer disintegration; Thedisintegrated particlesof the metal ar-e rolledl upo'n andbetween the individual streams-or jets'iof the two liquid streams" as they are: carried forward from the contact point and? so 1 gives or) forces them into a perfectly. spherical or globular for mation. The wholeactiontakes*placeuunder the predominate force "or pressure flow-of the' liquidlsubstantial flow force. In the first embodiment, the secondary stream H is maintained at a pressure force somewhat less than that of the main stream It]. In' the second embodiment, however, both are maintained at the same pressure-force. This pressure can be regulated at the source and by the :valve ll controlling the main stream in the first embodiment and both streams in the second embodiment. Of course a like'control may be provided for thesecondary stream, although it isnot herein shown. The pressure is regulated to a degreev at which the desired disintegration, or the disintegration into the desired size of particles will be produced and it may of course be varied according to the intendeddegree of shotting or working conditions.

In'this, a number of factors are to'be taken into consideration: First, the pressure orgravit-y' force with which the molten metal is discharged and the size of the stream in which'the discharge is made. Second, the distance from the point'of metal projection at which contact with the liquid streams," or either of the same, takes place. Third, the pressure of the two liquid streams or, in the case of the first embodiment, the pressure at which one is maintained in relation to the other. Fourth, the fineness of the individual streams .or jets of each component stream and" the extent to which said individual streams maintain their individuality or separation from each other in the projection from their nozzles. Fifth,

the fineness or degree of the shotting'to be produced, i. e. the size of the particles or globules into which the molten metal is to betransformed into granular material. Sixth; the'degree' or extent of disturbance or agitation caused by contact of the hot molten'metal stream with the colder, though possibly heated, liquid streams; Seventh, the character of the liquid streams and whether they are or are notof oily content such as oil emulsions or the like.

All ofthe above factors must 'be taken into consideration because they have arr-effect upon: the result. produced. Generally speaking, the smaller the size or thickness of the metal stream,

the smaller will be the degree of liquid stream pressure necessary to disintegrate it into the desired particles, or vice versa. Likewise, the greater the distance at which the metal stream contacts the liquid streams from its point of projection, the more severe the disturbance or agitation between the two will be, due to the accelera tive effect of gravity, and vice versa; Further,

the more refined or small the individual streams or jets'of the two main streams are, themore finely will they tend to break up the molten metal stream with which they are brought into contact, and vice versa, Again, a hardliquidwlll of course be moreharsh in itsactiontupon' the metal than'a soft or oily liquid would be. Finally,

the greater the pressure of the liquid streams, the more fine or minutelywill they tend to break up the moltenmetal stream. These various factors must be and are taken into consideration and adjustments madeaccordingly, depending upon thecharacter f of I the -results or resulting; It is simply a' matter of regulation and adjustment to suit the various.

product .to be produced.

the metal than hard liquidlik'e waterwo'uld 'b'e; It

is desirable also for the li'quid -tosbe'h eated or warmed to an extent that twill reduce-its*cooling or quenching effect upon the-metal; This will also tend'to reduce the disturbanceior agitation occurring; at. thepoint where tithemetal-and T liquid streamscom'e t'ogether.

The entire operation takes place-withini-ani enclosing chamber (not) sh'own) 'suchiii as1-shown' i or example in my aforementioned prior-Patentmedium or atmosphericsurrounding and "under" conditions which will not be.'-variable-. The'dis integrated particles of the; metal thus. broken i up into globules of'the desiredsiz'e are dropped into=.a quenching pool .(not sh'own) of liquidf iinthe bottom of.said"chamber;whereitheyareiur ther quenchedandco'oledto' thei'point' of com-- plete hardening, so that theyI'can' be removed, dried and properly treated 'forcommercial use.

The advantages of'this method of disintegrat ing or shottingmetalwill.undoubtedly be appreciated. It provides an operation attaining". de-

cidedly superior results, not only in*the"char acter of the productrecovered from'the' metal-,

but in the saving of wastage or fragmentary, in-

complete and purely." blastive disintegration;- A

very much higher proportion of 'perfect'shotting in usable form'amounting:"'to. as:"mu'ch :as-.2 5%

" more" in marketable-i sizes-is obtained and a greater "uniformity of size :in'th'etresultant par ticles is realized; Materiallyfreducing-as it does the loss of 'wastage.fromirregular fragmentary I -1s-more P Moreover," the means employed for the practice ofthis methodin eitherof-"theplansor' merev pulverizin'gi disintegratio economic.

or arrangements described. lends flexibility: to this systemin that the liquid system discharges hinge about swivel centers permitting themjto be swung or: adjusted r to. different. aligularfpositions or relationshipsto the metalstre'eIn? Thus;

the focal or most effective point offthe liquid streams can be brought. into play. againstth'e" metal stream so that their component'multiple disintegrating fine streams or jetscan' be'brought into play thereagainst,--or' adjustedptherwise to It will be understood that various modifications or various changes can be made in the application of the method and in the means for carrying the same into practice. Therefore, it will be appreciated that the invention is not limited to the specific plan or arrangement nor to the specific form or relation shown and described. Hence, the appended claims are not intended to limit the invention in any way beyond what said claims by their ownterms of definition expressly impose. 1

Having thus described my invention, what I claim 'as'newgand desire to secure by Letters Patent of the United States is: 1. The method of disintegrating metal into globular abrasive material, which consists in discharging a molten stream of the metal into the angle formed between multiple convergently meeting streams of liquid adjacent the line of intersection of said liquid streams, each-liquid streambeing projected under regulated variable pressure in the form of closely spaced series of solid pencil-like jets, between, through and around which the molten stream passes, shat tering the same, thereby uniformly dividing'said molten stream into drops which solidify into substantially round shape due to their surface tens1on.

' 2. The method of disintegrating metal into globular abrasive material, which consists in discharging a molten stream of the metal into the angle formed between two streams of liquid projected convergently' toward a common center, said molten stream impinging adjacent the line of intersection of said liquid streams, each liquid stream being projected under regulated variable pressure in the form of multiple closely spaced solid pencil-like jets maintained separate at least to the point of contact with the metal stream, and between, through and around which jets the moltenstream passes, shattering the same, thereby uniformly dividing said molten stream into drops which 'solidify into substantially round shape due to their surface tension.

3. The method of disintegrating metal into globular abrasive material, which consists in dis charging a molten stream of the metal into the angle formed between two streams of liquid projected convergently toward a common line of inters'ection, said molten stream being contacted with one of said liquid streams in advance of the other within said angle", each liquid stream being projected under regulated variable pressure force in the form of closely spaced series of solid 'pencilin like jets, between, through and around which the molten stream passes. shattering the same, thereby uniformly dividing said molten stream into drops which solidify into substantially round shape due to their surface tension.

4. The method of disintegrating metal into globular abrasive material, which consists in discharging a molten stream of the metal into the angle formed, between two streams of liquid projected convergently toward a common line of intersection, said molten metal being projected directly into the line of intersection of said liquid streams so as to contact both simultaneously, each liquid stream being projected under regulated variable pressure in the form of closely spaced series of solid pencil-like jets, between, through and around which the molten stream passes, shattering the same, thereby uniformly dividing said molten stream into drops which solidify into substantially round shape due to their surface tension.

5..The method of disintegrating metal into globular abrasive material, which consists in discharging a molten stream of the metal into the angle formed between two streams of liquid projected convergently toward a common line of intersection, said metal stream being contacted with one of said liquid streams somewhat in advance of the other within said angle, each liquid stream being projected and maintained under regulated variable pressure in the form of multlple closely spaced solid pencil-like jets; one of said liquid streams being trough-shaped and the other being in the form of a sheet, between, through and around which liquid streams the molten stream passes, shattering the same, thereby uniformly dividing said molten stream into drops which solidify into substantially round shape due to their surface tension.

6. The method of disintegrating metal into globular abrasive material, which consists in discharging a molten stream of the metal into the angle formed between two streams of liquid projected convergently toward a common line of intersection, said metal stream being projected directly into the line of intersection of said liquid streams so as to contact both simultaneously, each liquid stream being projected under regulated variable pressure in the form of closely spaced series of solid pencil-like jets forming a sheet or curtain, between, through and around which the molten stream passes, shattering the same, thereby uniformly dividing said molten' stream into drops which solidify into substantially round shape due to their surface tension.

7. Means for disintegrating metal into globular abrasive material, comprising in combination with a suitable enclosing chamber, means for projecting a molten stream of the metal from a supply source, means for convergently projecting two streams of liquid towards a common line of intersection into which said projected metal stream discharges. means for adjusting said liquid streams to vary the angle therebetween, and means for projecting each liquid stream under regulatory variable pressure force in the form of multiple closely spaced series of solid pencil-like Jets, between, through and around which the molten stream passes.

8. Means for disintegrating metal into globular abrasive material, comprising in combination -with a suitable enclosing chamber, means for projecting a molten stream of the metal from a supply source, means for separately projecting two streams of liquid convergently toward a common center in front of said metal stream so that the former will discharge into the angle formed between the two, means projecting said liquid streams in the form of multiple closely spaced series of solid pencil-like jets under regulatable variable pressure between, through and around which the molten stream'passes, and means for adjustably swinging said liquid streams to vary the angle between the two.

9. Means for disintegrating metal into globular abrasive material, comprising in combination with a suitable enclosing chamber, means for projecting a molten stream of the metal from a supply source, means for separately projecting two streams of liquid convergently toward a common center in front of said metal stream so that the molten stream will discharge into the angle between the two, means in the projection of said liquid streams for dividing them respectively into a multiple of closely spaced solid pencil-like jets composing the same through, between and around which the molten stream passes, means supplying said liquid streams under pressure force from a suitable source together with means for regulating the pressure of said supply, and means for separately adjustably swinging said liquid streams so as to vary or change the angle between the two.

10. The method of disintegrating metal into 10 globular abrasive material which consists in discharging a stream of molten metal into a closely spaced series of solid pencil-like liquid jets between, through and around which the molten stream passes, shattering same, thereby uniformly dividing said molten stream into drops which solidify into substantially round shape due to surface tension.

JOHN F. ERVIN. v

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