US921972A - Ingot-mold. - Google Patents

Description

E. GATHMANN.

INGOT MOLD.

' Patented May18,1909. QBHEETB SHEET 1.

E. GATHMANN.

'INGOT MOLD.

-APPLIOATION FILED NOV. 27, 1908.

Patented May 18, 1909.

, 2 EHEETS-BHIBET 2.

fw. B

UNITED STA EMIlJ GATHMANN, OF BETHLEHEM, PENNSYLVANIA.

/ I moor-MOLD.

Specification of Letters Patent.

Patented May 18, 1909.

Application filed November 27, 1908. Serial No. 4641,5465. I

'- citizen of the United States, residing in Bethlehem, in the county of Northampton andState of Pennsylvania, have invented certain new and useful Improvements in Ingot Molds, of which the following is a specification.

My invention relates primarily to that type of molds wherein are cast steel or alloy in ots which contract in their freezing or solidi cation from the hot liquid casting and-which are subsequently pressed, rolled or hammered into various commercial structural sha es and forgings. i

' e primary object of my invention is to provide a metallic mold whereby steel ingot castings can be so manufactured that the so-' called pipe or cavity, which forms in the upper middle portion of the ingot manufactured by the usual methods, is greatly reduced or practically eliminated.

Another ob'ect of my invention is to provide a mold w erein the liquid steel is rapidly cooled whereby ingotism or the formation of large crystals in the structure of the ingot is greatly reduced. v i

A further object of the invention is to so cool the mold by favoring radiation of heat from certain portions ofthe ingot that a cleaner and more homogeneous steel casting is roduced. j

y my improvements I effect a saving and make fit for structural or forging purposes a large percentage of the ingots usually cropped or scrapped on account of ipin-g and other imperfectionsincident to t e present manufacturing practices.

The accompanyin drawin s illustrate some of my designs for a mold adapted to o crate-in the manner above stated. They ll 'strate merely a few of the various ways of embodying my invention.-

.'F1g11l=8 1 shows a side elevation of'a form of mold which may be em loyed. Fig. 2 shows a vertical section t ereof. Fig. 3 shows a transverse section on the line P.P of Fig. 2 looking in the direction of the arrows. Fig. 4 is a view of thetop of the mold. Figs. 5 to 8 inclusive show several modifications of radiating surfaces. Fig. 5 shows such a surface formed with a number of relatively small pockets or depressions. Fig. 6 shows the surface formed with longitudinally vertic or vertically inserted ribs. Fi 7 shows such ribs arran ed horizontally. S shows a jacket coo 'ng device.

The mold A, shown in Figs. 1 to 4 inclusive, is substantially bottle-shaped, the portion below the line PP being the body portion and the portion above this line, the neck. The mold here shown hasside walls 13-, a top portion C, and a bottom portion D. The side portions B have interior surfaces E and outer surfaces F and G. The lower or body portion of the mold is constructed to favor the cooling of the molten metal in such portion much more rapidly than the metal in the upper portion or neck of the mold. This is done by giving it a greater heat absorption, conduction or radiating quality. In Figs. 1 2 and-'3 the outer surface F of the lower portion of the mold located below the line PP is given a mu hened contour and the surface G above the ine PP has a smoother con tour. This roughened surface is preferably provided by forming on the surface F vertically arranged outwardly extending spaced ribs H. In this way an increased radiating surface is presented per superficial area of the side walls of the mold in the lower part thereof. .Al-S hereinafter described, such increased radiating surface may be rovided in other ways, and other ways may e ad o ted for causing the lower part of the mo ten metal contained in the mold to cool more rapidly than the upper art thereof. Ham dles- K may be fitted to t 1e mold for convenience of manipulation and transportation in the stripping of the cooled ingot. 'llhe mold should be seated on a stool or platform, in

the usual way, for closing its. lower portion during-the casting or coolingof the ingot. The radiating ribs- H, shown in Figs. 1, 2 and 3, are referably disposed in an upright or al direction in order that induced currents of air may be created which insures a better cooling of the ribs by convection, but forced air currents may. be directed; against such portions of the mold as require rapid cooling, if desired.

Instead of employing vertically arranged ribs, as shownin Figs. 1, 2-, 3' and 6:, I may arrange the ribs horizontally, as shown in Fig. 7, or I may merely form ockets or recesses in the walls of the mo (1 with correspondin projections, as shown in Fig. 5: I may, if esired, provide for the'rapid cooling water-or other cooling of the lower ortion of the mold by a cooling jacket, as'in icated in 8, throu h which uid may e circulated. In all cases the lower ortion of the .5 mold is so formed, or is so equlpped, that an increased radiating surface is provided per superficial area of the side walls of the lower part of the mold, or such lower portion of the mold is given, in other suitable ways, a 10 greater quality of radiation, conduction or convection-than the upper part thereof.

In theuse of my inventionthe mold is preferably pre-heated to the desired degree in order to avoid sudden strains, the liquid steel is then teemed or poured into the mold from a ladle, or the like, in' any suitable way until the'mold is filled, preferably up to, or near its upper end. The heat from the liquid steel is then rapidly conveyed from the inner surface E of the side walls B by conduction outward to the surfaces F and G upward to the top 0 of the mold and downward to the.

surface D. The heat from the liquid steel having thus passed by conduction to.the

outer surface of the mold is further transmitted by radiation and convection into the surrounding atmosphere. As the speed of heat radiation from any similar body is directly proportional to the exposed surface and 1S also'governed by the character of the surface, the heat will radiate far more rapidly from the rough surface F or the ribs H than from the smoother surface G. It thus follows that the upper portion of the ingot will .35 retain its heat for a much longer period of time than the lower portion thereof, or,

rather, the lower or body portion of the mold will be cooled far more rapldly than the u per portion thereof. The up er portion 0 the 40 molten metal thus being t e last to cool will feed liquid steel tothe ower portion of the molten metal as the latter freezes and contracts. This contraction takes place as is well understood frdm a neutral longitudinal 4 axis and usually forms the so called pipe, but

by my improvements this pipe or cavity is automatically filled by,the liquid metal fed to it from above and so the pipe or cavity in the cast ingotis by my improvements prevented.

The entire time of freezing for a given size of ingot is considerably reduced by my improvpments as the radiation of heat is greatly enhanced from the major ortion of the y outer side surfaces of the mo d.

' The exact location of the line P-P at. which the radiation favoring and non-favore ing surfaces of the mold meet cannot be definitely determined; except by experiment for specific sizes and depths of molds. ,I

have, however, found by experiment that 'P p comp ish the, desired result by simple and 7,5

the part G should not extend beyond one and i a half-times the largest horizontafiiross section of the ingot being cast in order to avoid pipling action.

inexpensive'means.

, No claim-is made herein to the method herein described'as such method is claimed in my application No. 481,888, filed March of steel I claim as my lIlVGIllDlOIll 1. A mold, the upper part or neck of which has a relatively smooth contour while the lower part of the mold is provided with a'series ofradial outwardly extending ribs.

2. A mold having its magor outerportion of a roughenedcontouran the upper neck portion of a relatively smooth contour where' by heat radiation from the lower portion of the mold is more rapid than from the upper portion. a

3. A metallic mold provided with means for favoring heat radiation, conduction and convection from its lower portion, while its upper'portion is. relatively smooth and has less of these qualities.

4. A metallic mold formed with substantially vertical retaining walls. provided with heat radiating means in the major portion of its outer surface and having a contracted upper vertical portion, the side walls of which are disposed in a plane other than that formin the contour of the major portion of.- the mo d.

lower ortion of which below the neck is forme to-favor heat absorption to a greater extent than the neck whereb. the molten metal in the neck of the mol is caused to descend and fill the pipe or cavity formed in the lower portion of the metal.

"6. A metallic mold, the lower ortion of which is constructed or equippe to fa'vor the cooling of the molten mass'to a greater extent at,the bottom and lower part of the llfi mold than at the upper art thereof.

. In te'sti'monywhereo I have hereunto subscribed my name. EMIL GATHMANN.

Witnesses:

y R. W. LEIBERT, PAUL J. GATHMANN.

5. A bottle-shaped metallic mold, the 1 5

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