US1887296A - Production of sound ingots - Google Patents

Description

PRODUCTION OF SOUND INGOTS 4 Sheets-Sheei;

A. G. EGLER PRODUCTION OF SOUND INGOTS Filed Aug.l 15, 1952' Nov. 8, w32. l

Nov. s, w32. A G, EGLER Lssgs A PRODUCTION OF SOUND INGOTS Filed Aug. l5, 3.952 1 4 Sheets-Shee 6 EH? M if wf may Am m4 j@ .w w

NOV. f8, 1932. G, EGLER 1,8879296 PRODUCTION OF SOUND INGOTS Filed Aug. 15,` 1932 4-sheetssheet 4' mwm Patented Nov. 8, 1932 UNITED STATES ANDREW G. .EGLER, OF YOUNGSTOWN, OHIO PRODUCTION OF SOUND :INGOTS Application fue@ August i5, 1932, serial No.

My invention relates to the production ot sound ingots and has particularly in view the production ot a steel ingot that will be. substantially free `from blowholes and slag inclusions.

The ingot is produced by arring the metal in the mold from the beginning of pouring` and continuing while the metal is molten and until the desired results are obtained. To secure the best results, the metal is subjected to jarring in a vertical direction and at such a regulated velocity and speed ot jarring as will cause separation of substantially all ot the non-metallic inclusions and avoid splashing of the metal in the mold.

This application is a continuation in part of my applications, Serial No. 318,190. tiled A\'ove1nber E), 1928. and Serial No. 530,984, tiled April 1T, 1931.

lt has been heretofore proposed to produce sound ingots by jarring the metal in the mold but none ot these have ever gone into commercial use. This has been due to the absence ot a number of features embodied in my invention` whereby I am enabled to commercially produce sound ingots. The most important ot these include the step of jarring the metal from the beginning of pouring, rather than from such time as when there is a certain quantity ot metal in the mold and utilizing a regulated jar so as notv to splash the metal in the mold nor bounce the mold on the stool.

It is not convenient nor desirable to anchor molds to stools. therefore it is important that such jarring ab; is necessary to obtain the desired ingot should be at such a velocity as to make sure that the mold will not bounce upon the stool and thus allow the metal to seep between the mold and the stool. rl`he jarring should be done at such a velocity so that the metal does not splash upon the sides ot' the molds and so tend to canse scabby surface on ingots.

The jarring is most etfective when the fluidity of the metal and its depth facilitates the separation of the gases and the nonmetallic inclusions, due to their buoyancy or low specific gravity. By jarring from the beginning ot pouring, the non-metallic in- 628,904, and in Canada November 19, 1928.

clusions are promptly brought to the top of the metal and are readily kept there or near there throughout the pouring operation, so that thereafter they are readily eliminated.

Due to the dilierence in the specific gravities of the metal and the non-metallic inclusions, a jarring action, with a velocity which doe-s not cause the steel to splash upon the sides of the mold, is sutlicieut to cause the ebullition or agitation in the steel necessary to free the non-metallic inclusions.

The ingots should be jarred preferably with a vertical, heavy, sluggish blow in both the rising and falling motions. rThe. down jar if at low velocity does not cause the steel to bounce to a detrimental.height, but the non-metallic inclusions do increase their buoyancy relatively and rise promptly. The .up-jar produces a quivering or trembling etfect in the body ot' the metal due to the triction between the platform and the cam with the very l *avy loads involved. This trembling or quivering etlect, that is very noticeable on the rise of the mold, seems to releasethe gases from the body ot' molten metal. The 5 direction ot the jarring torce is preferably vertical to insure the operation against splashing ot mctal against. the-molds.

The jarring should begin with the irst drop ot steel and continue tu'iinterruj'ited, if 80 possible. to take every possible advantage of the temperature and fluidity of the steel and until the desired results are obtained. rlh'e eti'ect ot'a jarringl action ot this hind is to keep the molten metal continuously in such a. state of agitation that it resembles ebnllition. Due to the low velocity ot the jarring motion. thesteel does not bounce in the mold to a detrimental height and docs not splash against the sides o" the molds.

It is obvious that there could be considerable variation in the means for producing this character ot agitation in the molten metal.

Conventional steel ingots may be jarred for various lengths of time depending in part on the tapping temperature. the teeming temperature., the carbon and manganese content oi the steel as well as the size and shape ot the ingots. J arring alter complete solidification of the ingot has taken place is objectionable because it tends to increase mechanical pipe in the ingot.

lVhen steel is poured into molds in theregular way, the bottom and corners are most rapidly chilled by contact 'with the molds and stools because of the relatively larger mass of the cold mold or stool which is brought into Contact with a. relatively small area of ingot face. The sides of the ingots present a much larger area in contact with the lesser mass of the cold molds, hence, the ingots made in the regular way show black bottoms and corners and red center panels. For example. if a foot or so of metal is poured into the mold before the jarring action commences, the bottom and corners of that portion which was present before jarring are chilled promptly and the sides also to a lesser extent.

As the pouring continues, the jarring action forces the upper part of the ingot while it is in the process of solidifying into this lower thin skinned box and the shell of the ingot Awhen shipped will be cracked at the bottom and at the corners. When the steelis shaken from the start., the metal is all in motion or agit-ation and a more uniform temperature is held in all the steel so that the skin is slowly formed bythe more gradual reduction of the temperature of the steel near the mold.

In the regular unjarred ingot, a thin skin is promptly formed by contact with the relatively cold mold and as the nlolten interior cools it shrinks away from this skin and so a sponginess exists very close to the surface of the ingot and extending inwardly a sub-stantial distance toward the more solid heart of the ing'ot.

' In the jarred ingot, this skin does not so form because all the metal is kept in a state of ebullition or agitation but instead a shell of substantial thickness and great density builds up slowly surrounding the sol-id heart ofthe ingot.

IVhen the regular ingot is rolled the thin skin is often ruptured and so the resultant bloom is seamed and pitted, whereas when the jarred ingot is rolled the heavy skin insures the smooth surface ot' the bloom.

The. density ot' the jarred ingot is 79k' to 12% greater than the unjarred ingotj that is, with the same volume the jarred ingot will weigh 7% to 12W more than the regular ingot, and there is present on top of the jarred ingot five or six times the amount of slag.

Such blowholes or voids as exist are free from slag or other non-metallic inclusions and they are deep seated and the lower portion of the ingot is particularly solid.

The regular unjarred ingot not only has more blowholes than the jarred ingot but they contain non-metalli(l inclusions ineluding Lesage@ slag and particularly so in the lower portion of the ingots.

All regular unjarred ingots, of any carbon content, when stripped show cold black eorners and edges, leaving ay red panel on each side. The jarred ingots, when stripped, present an even red glow, all over.

rIhe effects of jarring the ingot, according to my process, on the physical properties of the metal are far reaching.

A photomicrographic etched section of an unshaken ingot will show large slag inclusions and smaller slag inclusions together with anotherwise irregular crystalline structure. A section of a j arred ingot will show a uniform crystalline structure, without any noticeable slag inclu-sions.

It is clear to those skilled in the art that ordinary voids, if free from non-metallic inclusions, if their surfaces are clean, will readily Weld perfectly in the rolls or under the hammer or press and yield a marketable product for ordinary requirements, hence the yield of ingots is markedly increased.

The physical properties of the sheets made from jarred ingots show an improvement in physical characteristics and particularly is the ductility increased. thereby making such sheets very desirable for deep drawing operations, such as for bodies of automobiles.

Steel having a chemical composition comprising approximately 0.11 carbon` 046-048 manganese, 0024-0031 sulphur and 0.010- 0014 phosphorus was found. after shaking to have increased the elastic limit from 23.440 lbs. per sq. in. to '29.510 and the ultimate strength from 41.850 lbs. per sq. in. to 47.780.

In a ductility test in the Olsen machine, the unshaken steel registered from 390-104, whereas the shaken steel of the same composition ranged from 430-140.

One of the means that is now utilized in steel mills for producing ingots comprises a train of cars, carrying ingot molds. supported on stools. sufficient for a full furnace heat. This train is drawn up alongside of the pouring platform where it remains while the entire heat is being poured. If the stool. or the car on which the stool rests. or the track on which the car runs, is repeatedly jarred from the beginning of pouring and while the metal in the mold is molten. then the metal will gradually settle down in the mold and thc ingot on solidifieation will be solid, as desired.

The jarring platform should be designed to jar the ingots at any desired number of ljarring impacts ranging from about 20 to (30 impacts per minute. with a rise and fall of about one-half inch. The rate of the rise and fall depends on the shape of the jarring eam and its` speed of rotation.

To satisfactorily jar the metal to free the non-metallic inclusions from the ingot. it is apparent that there can be considerable latitude inthe velocity of the jarring motion which may serve the purpose. The jarring motion should be such as to separate the non@ metallic inclusions from the steel and not cause the steel to splash in the molds, or the molds to bounce upon the stools.

Referring to the drawings for a more complete dsclosure of the invention:

Fig. 1 is a plan view of an open hearth steel plant showing the location of a jarring platform.

Fig. 2 is a vertical section on the line 2-2 of Fig. l,

Fig. 3 is a plan view of a portion of the platform,

Fig. 4 is a section on the line l-l of Fig. B.

Fig. 5 is a section on the line 55 of Fig. 3,

Fig. 6 is a vertical transverse fragmentary section of the jarring platform,

Fig. 7 is a detail section showing the guide for steadying the platform.

Fig. 8 shows the preferred shape of double pointed cam,

Fig. 9 shows a triple pointed cam, and

Fig. l() shows a single. pointed cam.

In the usual open hearth plant for the manufacture of steel, the open hearth furnaces 10 are located at an elevation and along one side of the pit 1l. On the other side of the pit are loated the pouring platforms l2. 'l` he pouring tracks 13 run along side of the pouring platforms. lVlien a heat is ready to be poured. the train of ingot cars are drawn up along side of the pouring platform, on to the .stationary tracks. The operator standing on the pouring platform operates the laddle stopper to let the metal run into the molds, one after the other until the heat is all poured.

In my invention. instead of having stationary tracks 13 along side of the pouring platform 12. l carry this portion of the track upon a platform designed to be jarred while the metal is being poured and in a molten condition. The ingot cars 15 are of the conventional type and the usual number form a train. The whole train may be carried b v the jarring platform on which are mounted rails 1G, and on which rails the car wheels 18 rest during the jarring. 'l`he molds 1T are for the conventional large bottom ingots and are supported on the conventional stools 19.

The jarring platform frame is preferably made of rolled steel girders or -beams 2l). extending longitudinally of the platform and spaced cross frames 21 riveted to the main girders and extending transversely of the platform. (ln the frame. a suitable deck 14 is supported. The jarring platform as thus constructed will have the rigidity necessary to distribute the load to the sev-eral points of su'pport which are the jarring elements. The girders are spaced apart a distance equal to that of the standard track gauge so that the track rails 16 will'be directly over and reinforced by the girders 20.

The jarring platform isdivided up into a number of sections 24, 2 5, 2.6 and 27. Each section is long enough to hold two cars 15, the four sections holding the usual train of eight cars. In use, the coupling .28 between the cars is located directly over the meeting point of the separate sections. There is a separate power unit for each section so that they can be jarred independently of each other. 'The rise and fall of each section is about one half of an inch and there is suflicient play in the couplings between the cars to permit the jarring of any sectionwithout having to uncouple the cars.

For jarring each section there are provided rotary cams 29. designed to give the desired jarring movement to the platform. These cams are keyed to parallel shafts 30, extending longitudinally of the platform, and mounted in bearings 31 resting on the foundation 32. For rotating the shafts 30, a separate variable speed motor 33 is provided for each section. Keyed onthe motor shaft 3l is a piuion gear 35 engaging a larger gear 36. Keyed on the same shaft as the gear Sli is a small spur gear 37 which meshes with the spur gear 3S keyed on one of the cam shafts St) and meshing with asimilar sire gear 1li) of the same number of teeth keyed on the other parallel camshaft :30. lith this arrangement of speed reducing gears. the cams 2t) will rotate at the same speed and synchronously. Each section of the jarring platform'is accordingly provided with two pairs of jarring cams located directly under the supporting tracks 16 for the ingot car.

On account of the very heavy loads that mustl be arred. the friction should be reduced as much as possible and with this end in view the under side of the jarring platform is provided with anti-friction rollers'lt) spaced apart-`longitudinally of the platform so as to properly distribute the load. and provided with stub shafts -l1 rotating in bearings 42 secured to the under side of the platform.

For guiding the platform in its up and down movement. I provide alinement boxes 4?). 0n each side of the platform are-mounted rollers it which engage with the said boxes 423 through .the medium of adjustable shims that may be provided for securing the desired adjustment and taking up the wear.

The jarring elements 29 have a periphery of such a shapeso as 'to conserve power. and impart the desired lifting as well as falling jar to the platform. In the preferred form shown in Fig. 8. the jarring elements 2S) have cam shaped project-ions lf3 at diametrically opposite sides. which abruptly raise and drop the platform twice for each complete rev'olution of vthe jarring elements. The jarring element is formed so that the distance a: between the arrows is about one-half an inch, which represents the risc and fal of the rollers lt) and the jarring platform.

The lines 3f are tangent to the circle a as shown at somewhat less than 90 apart, the point a being rounded ofi' where the tangent lines intersect. A jarring element of this design will so regulate the velocity as to produce the desired heavy sluggish blow in both the rising and falling motions. In order toredu'ce friction, the construction of the jarring elements is such as to provide a. clearance of about one eighth of an inch between the circular portions of the jarring elements and the rollers 40; that is to say, the rollers are held out of contact with the jarring elements except when they are in Contact with the cam shaped portions. This end is attained by limiting the downward movement of the jarring platform and hence the rolle-.rs through the medium of the bumping blocks t7 carried by the foundation which engage with the platform under the cross girders 21.

The lifting points on the three point cam shown in Fig. 9 and the one point cam shown in Fig. l0 are the same design and produce the same action as with the two point cam.

Fly wheels 48 may be provided to secure the necessary movement and the gears may be provided with cases 49.

lVhen the train of cars with the empty ingot molds is in position on the jarring platform which is along side ofthe pouring platform and the steel ladle is in place to pour the heat, the motor is started and the jarring machine is started with the beginning of pouring of each section and continued at a predetermined rate until the ingot has reached a definite state of solidiiication` then the machine is sluit down. To one skilled in th i art, there are definite indicators which become apparent as the lirst ingot is poured, and these indications determine the rate .of jar as well as the length of time the ingot is jarred. Any one or all of the sections can be operated independently as desired. The train of cars is then removed as usual to the ingot stripper and stripped in the usual way.

lt is obvious that the platform may be shorter than the whole train length and each ear or any desirable group of cars `may* be handled in a similar manner to a whole train.

From the above description, it will be clear thatl provide a method of jarring steel in which there is a closely coordinated control of the various forces to produce a state otl agitation in the metal which resembles .the ebullition or vigorous boiling of liquids. lhen this state of agitation is present, there is a continuous opportunity for the escape of gases and slag from the metal without splashing the metal on the sides of the molds or causing the mold to bounce ofi' ot its stool.

lVhile li have described my jarring method with much particularity, the present disclosure is to be considered in all respects as il` lustrative and not restrictive and it will be recognized that variations may be made withof substantially all of the slag sluggish blow in both the rising and falling motions and continuing the jarring until substantially all of the non-metallic inclu` sions have been brought to the top of the mold.

3. A method of producing sound steel ing gots comprising pouring the metal in the mold, replatedly jarring the metal with a. vertical heavy. sluggish blow, the vertical velocity and speed of jarring being controlled so as to prevent splashing of the metal in the mold and cause rising of substantially all of the slag to the top of the metal.

l. A method of producing sound steel. ingots comprising pouring the metal in the, mold` repeatedly jarring the metal with a vertical heavy, sluggish blow to cause a rise and fall of the mold of approximately 0nehalf inch and at a velocity that will prevent splashing of the metal in the mold and cause rising of substantially all of the slag to the top of the mold.

5. A method of producing sound steel ingots comprising pouring the metal in the mold` repeatedly jarring the metal from the beginning of pouring in both a rising and falling direction and at a regulated velocity and speed of jarring so as to prevent splashing ot' the metal in the mold and cause rising to the top of the metal.

G. A method of producing sound steel ingots comprising pouring the metal in the mold, repeatedly jarring the lnetal from the beginning of pouring with a vertical heavy, sluggish blow causing a relatively small rise and tall of the mold, at such a regulated velocity and speed of jarring as to cause a separation of substantially all of the non-metallic inclusions and avoid splashing of the metal in the mold.

'i'. A method of producing sound steel ingots comprising pouring the metal in the mold, repeatedly jarring the metal from the leginning of pouring with a vertical heav sluggish blow to cause a rise and fall of the mold of about one halt' an inch and a separation oi substantially all of the non-metallic inclusions. the number of jarring impacts being about i2() to t3() per minute.

8. A method of producing sound ingots comprising pouring the metal in the mold, subjecting the mold to #vertical jarring impacts during pouring and while the metal is 5 molten, at a rate of the order of about 20 to 60 impacts per minute, the vertical movement of the mold being of the order of about a. half an inch, to thereby cause separation of substantially allot the non-metallic inclul@ sions and produce a state of continuous agitation in the molten metal resembling ebullition and avoid splashing of the metal on the sides of the mold.,

9.'A method of producing sound ingots 35 comprising pouring the metal in the mold,

subjecting the mold to vertical jarring impacts Jfrom the beginning of pouring at a rate of the order of about 2O to 60 impacts per minute, the vertical movement of the 2@ mold being for a predetermined distance and of the order of a fraction of an inch, the jarring action producing a state of continuous agitation of the molten metal, which causes a rising of the gases and substantially all of the non-metallic inclusions to the top f the mold.

In testimony whereof I afix my signature.

ANDREW G. EGLER.

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