US2799906A - Apparatus and method of filling ingot molds - Google Patents

Description

INVENTOR, WILLIAM M. DUNCAN,

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A TTORNEY5 W. M. DUNCAN Filed Jan. 26, 1955 APPARATUS VAND METHOD OF' FILLING INGOT MOLDS July 23, 1957 United States Paten-t APPARATUS AND'METH'OD OFFILLING INGOT MOLDS M. Duncan, Alton, Ill.

Applicationlzlanuary 26,1953, Serial No. 333,317

V-2 -Glaims. {Cl.'22"15`5) This invention "relates tomethods-'of and `apparatus for pouring ingots.

One of the principal problems confronting the industry has been that yof preventing piping or spongy spots from occurring in the center of ingots. It will be understood that when metal poured into an ingot mold freezes, there is a reduction in volume or shrinkage of crystallization, which ltends to produce voids in the center portions of the casting. Such voids result in structural weakness when the ingot is later Worked, as by forging or the like. Accordingly, it is an object of this invention to avoid formation of such piping in pouring ingots. Another object of the invention is to provide for continuous pouring of ingots, using conventional open-top ingot molds.

In accordance with this invention, biiey stated, molds are arranged in a row and are connected together at their sprues by inclined runners. Once a mold is filled, liquid metal is caused to tiow over its sprue to feed shrinkage therein, While the excess metal over Ithat required to feed shrinkage is directed by the runner into a next mold. More particularly, conventional yopen-top ingot molds are carried on cars moved along an inclined track leading up to the pouring station. A refractory covering is placed on top of the molds to form a continuous runner extending the length of the train, with sprues opening from the runner into the mold cavity. Metal is then poured in the runner adjacent to the upper end of its incline to lill molds as they are moved to lthe pouring point, and feed shrinkage in a lled mold as it moves beneath the pouring point.

Pouring is preferably continuous, but the first mold is not moved from beneath the ladle immediately upon being lled. Instead, metal is poured or caused to ow over the associated sprue for a 'substantial length of time thereafter, the overflow being directed by the runner to ll a following mold. The mold movement may be continuous, but any given mold should be tilled before its arrival at the pouring point so that 'there is an opportunity to feed shrinkage from the runner before the mold moves Ibeyond the pouring point. In this way, an adequate supply of liquid metal for feeding shrinkage in the mold proper is not only assured, but heat is supplied to the metal in a sprue opening so as to prevent premature freezing of metal at the sprue.

Other features yof the invention will be in part apparent from and in part pointed out in the following detail description taken in connection with the accompanying drawings, in which:

Fig. l is a top plan view illustrating the invention as employed in pouring ingots; and,

Fig. 2 is a side elevation of the apparatus shown in Fig. l, parts being shown in section.

Referring now to the drawings, molds 1 lare arranged in a row for relative movement with respect to a pouring station. In the illustrated embodiment, the molds are carried by trucks 3, which are coupled together at 7 in uniformly spaced relationship, and the trucks are moved 'along a track 5 in the direction indicated by a suitable de- Patented July 23, 1957 ICC Vvice (not shown). YThe molds i1 iareconventional ingot Aeachfmember'functions toschannel-:tlow-of liquid metal lbetween Walls-'17,"and-atfthe ends of the jgroove yare recesses 19, which for-m 'relatively-'smallsprueeopenings for filling the molds.

In operation, the covers 13 are `arranged in -endabutting relationship on ltop of the molds, eac-h member 13 reaching from the `center of one mold to the center of an adjoining mold. The molds are thus closed except for relatively small sprue openings 19 which are connected together by a continuous runner extending the length of the train. Metal is poured into the runner from a ladle 21 or other source of liquid metal located at a point adjacent the upper end of the inclined part of the track.

At the beginning of a pouring operation, |the initial mold is moved generally beneath the ladle 21 and filled. When lled, the mold is not immediately moved from beneath the ladle, ibut liquid is all-owed to low ont-o or over the associated sprue While rthe metal in this initial mold cools and sets. Consequently, a continuous supply of hot liquid metal is present at the sprue to feed whatever shiinkage occurs, the excess over that required to feed shrinkage being -directed by the runner 15 into a following mold. After the possibility of shrinkage at the iirst mold has passed, the molds may be moved continuously as a unit until the pouring operation yis completed.

During movement of the molds, met-al continues to ow from the ladle, but it will be apparent that the molds are filled before they reach the ladle. In other words, a given mold arriving at the pouring station 23 has been filled previously from the runner 15, and shrinkage is in progress; however, such shrinkage is adequately fed from the runner as the mold moves to and beneath the ladle. As the last -mold in the train approaches the ladle, the pouring may be stopped, in which event some shrinkage will loccur in the iinal ingot, but that ingot may be remelted. After the pouring operation has been completed, the covers 13 are removed from the molds to permit Withdrawal lof the ingots.

The rate of ow at 23 and lthe rate of mold movement are controlled relative to one another 4so as to maintain a stabilized condition Vduring the pouring operation; and both metal ow and mold movement `are adjusted relative to the time required for the metal in a filled mold to freeze. For example, the time required for the metal in a mold to set after lling, the time required to lill mold C-1 and feed shrinkage at B-l (as determined by the rate of oW at 23), fand the time required for mold C-l to move to the ladle yafter filling (as determined by the speed of the trucks 3), should all be approximately equal.

From the foregoing description, it is -apparent that those skilled in the art will understand the structure, methods, function, and mode of operation Aof the invention herein disclosed, and appreciate the advantages thereof. It may be noted, that Whereas the invention its described in particular as utilized in 'the pouring Iof ingots, the invention may also be used in pouring other types of castings, and reference is made lby my copending application entitled Manufacture of Castings, Serial No. 333,316, filed January 26, 1953.

Although [one embodiment has been disclosed in detail, itis to be understood that the'invention is Ynot limited thereto, but the drawings and description thereof are to be understood as being merely illustrative.

It is realized that other modifications and variations will present vthemselves -t-o those skilled in the art without departing from the spirit lof this invention or the scope Y thereof as set forth in the appended claims.

Having *thus described the invention, what is claimed and Idesired to be secured by Letters Patent is:

l. Apparatus for lling conventional open-top ingot molds comprising a track inclined to a pouring station, a plurality of cars on said track, each of said cars carrying an ingot mold, and re-usable cover sections laid in endabutting relationship on top of and lbridging adjacent molds, said cover sections 'being shaped to form an open -trough extending lengthwise of the rtrain with sprues op ening therefrom into said molds at vthe abutting ends of said cover sections. Y Y

4 2. A re-usable cover section for use in pouring ingots with conventional open-top ingot molds which are carried on -a train of cars, said cover section being formed of refractory material and being of `a length suicient to extend between the centers of adjacent cars and -of a width `suiicient -to cover the top of an ingot mold, said cover section having a groove extending lengthwise from end toend, and a sprue-forming recess extending across one end thereof from said groove.

References Cited in the file of this patent VUNITED STATES PATENTS 521,449 Adams June 19, 1894 735,303 Sauver Aug. 4, 1903 1,454,741 Howard et al. May 8, 1923 1,572,866 McKune Feb. 9, 1926 2,326,164 Payne Aug. 10, 1943

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