US2373036A

US2373036A - Method of casting ingots

Info

Publication number: US2373036A
Application number: US492953A
Authority: US
Inventors: Lewis B Lindemuth
Original assignee: STEEL INGOT PRODUCTION Inc
Current assignee: STEEL INGOT PRODUCTION Inc
Priority date: 1943-06-30
Filing date: 1943-06-30
Publication date: 1945-04-03
Anticipated expiration: 1962-04-03

Description

v 3 036 l.. B. I lNvDElx/IUTH` 2,37

June 50, 1943 INVENTo. LEWIS 5.-L/NDEM H.

' ATTRNEK 7 HWMIE/ April 3, 194,5.

Patented llApr. 3, 1945 s `lea'rvrsilv'lA OFFICE Marnon or @asumo moors p Lewis B. Lindemlith, Port lll. assigner, by meoue ausente, to Steel lnzot stom.

Production, lnog, a corporation ol ware Application .le dll, luth, Se lo i No. 492,953

' (oi. et-evm My invention relates to ingot molds and a method of casting ingots of ferrous metals, such as steel or other metals.

lngots of steel or other ferrous metals are generally cast in iron or steel molds, which may have either an integral or removable bottom. In either case the molten metal upon pouring or teeming into the empty mold strikes the bottom ol the mold with considerable force and being at the melting temperature tends to wear away or erode that portion of the bottom ofthe mold on which it impinges.- IThis has a tendency to form cavities in the mold, or the bottom of the mold.

and after cavities havethus been formed or eroded in the mold the cast metal may solidify therein and may partly weld thereto and thus make it dlfiicult to remove the cooled ingot from the mold.

My present-inventionprovides an ingot mold and a method of casting the ingot in such a way w1 as to prevent or minimize this erosion of the bottom surface of the mold and to avoid the tendency oi ingots to stick to the mold.

In my invention I protect the bottom surface of the mold cavity with a layer or dim of lead mi in such a manner that when the molten steel, or other ferrous metal, is poured or teemed into the `mold it does not strike the metal oi the mold directly but instead lmpinges on the lead.

inasmuch as the lead melts at a much lower temperature than steel and has a greater density or specific gravity and does not alloywiththe steelit`not only protects the bottom of the l vmold from erosion but when the mold is lled r as` a liquid layer or llm between the bottom of the mold and the insot and does not in any way interfere with the insot.

composition oi' the inasmuch as ne lesa is man 'itis displaced only temporarily by the molten `steel as the latter t0 e oi the pouredrmetal may be expended in displac- .is poured into the mold and though it may be ,displaced temporarilybythe stream of molten metal it inmediately sinks a the bottom of the mold as the lling ol the mold proceeds and as .the lower part-oi the metal becomes quiescent.

There is, therefore, no erosioneilece se. fm as the leadisconcerned. i

owing' to its meros it provides an effective vcushion between the poured metal and the inner surface at the bottom of themold. AiterthoA mold andA ingot have cooled the ingo't may be remGYed leaving the lead in the mold eithervas a. soiidiecl layer or in the molten condition. de-

pending upon-the temperature at which the inset irmoveq f l a cient amount of Altu'ittorn of lin the case ol a mold having a solid or closed bottom, in which case the walls taper downwardly, it is only necessary to put into the'mold lead'to fox-m a layer of the desired depth.

In thecase of an open bottom mold closed by a bottom plate or plug, I prefer to provide a lead seal outside of the lower part of the mold through which lead may be displaced by the weight of the molten steel. However, it'will be apparent that any other type of bottom closure y be employed.

The various features of my invention are illustrated diaeratically, by way of example, inthe accomp drawing in which Fia. l ls a vertical section of a closed bottomA ot mold embodying my invention, and

Fie. 2 is a similar section of an open bottom mold.

erring to the embodiment shown in Fia. l the invention is illustrated as applied to an ingot ld ha a. bottom it and an upstanding or upriuht wall lll which tapers downwardly so that thesolidied ingot may readily be removed therefrom. The upper end of the mold may be provided with a hot top ring it. lnto the mold there is placed a quantity of metallic lead which melts and forms a pool il when the mold is heat above the melting temperature oi' 'the lead. It will be understood that il the lead is in 'bottom ci i the mold the teeming steel must displace or erode the lead before it can reach the bottom of the mold and with a suilicient thickl s@ oi lead, depending upon the dimensions of mold and the conditions of teeming, the force the lead without actually contacting with the bottom oi the mold or contacting it with nicht? force that no substantial erosion m Fie. 2 the invention is illustrated as applied to an open bottom mold having a vertical wall il which tapers upwardly so that the mold con be lifted upwardlyv from the solidled ingot. The the mold or mold cavity is closed by a bottom plate i5 'spanning the area of the mold and extending below the lower edge of the mold wall and thence upwardly as et i8 to f/orm a narrow channel or moet l1. A layer I l'of molten lead within the mold m may new or seep inw the channel Il without being lost. When molten i steel'is poured into the ingot its force or impact will be taken up primarily by the layerv of lead I8 and when the latter is entirely molten it might be displaced to a greater or less extent beneath the wall of the ingot M and into the moat or channel l1 before the lower part .of the'molten metal solidies in the mold. In any event, however, the layer of lead takes the impact of the molten steel and thus protects the bottom plate i5 from erosion. Erosion of the lead is of no consequence because it immediately takes the form of a liquid which does not alloy with or stick to the steel ingot. y

Through the above invention the surface o the mold on which the molten metal impinges is protected by a displaceable layer of metal which, having a melting point below that of the steel, assumes a liquid form against which erosion has not permanent effect.

inasmuch as the lead forms a smooth layer below the cast ingot and does not alloy with it. the ingot may readily be lifted from the bottom wall of the mold.

What I claim is:

1. A method of casting ingots of ferrous metal which comprises covering the bottom of an ingot mold cavity with lead and pouring molten ferrous metal into said mold so that the stream of molten ferrous metal impinges directly on the lead.

2. A method of casting ingots of ferrous metal which comprises covering the bottom of an ingot mold cavity with a layer of molten lead and pouring molten ferrous metal into said mold so that the stream of molten ferrous metal lmpinges f directly on the lead.

3. A method of casting ingots ci ferrous metal which comprises placing lead in an empty ingot mold and pouring molten ferrous metal into said mold so that the stream of molten ferrous metal impinges directly on the lead.

LEWIS B. LINDEMU'I'H.