US2190209A - Apparatus for eliminating pipe, etc., in metals - Google Patents

Description

Feu- 13, 1940.

G. W. HAZEY AAPPARATUS FOR ELIMINATING PIPE, ETC. IN METALS Original Filed Dec. 7, 1934 BYv INVENT OR.

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ATToRNEYd,

i riemenv Feb.' 13, 194cwtzoa George W. Haney,

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Cleveland, Ohio, assigner, by

direct and mesne assignments,`of twenty-iive per cent to Richard C.v Tuma,

Los Angeles,

Calif., sixv and two-thirds percent/to H. H.

'Handelmam Cleveland;

Ohio, ten per cent to Edward Gadd, Leavittsburg, Ohio, and twentyfive per; cent to Elias C. Tuma, Cleveland, Ohio Original application December '1, 1934, Serial No.

Di -led and this application April 1,\

193s, serial No. 199,381; K

1 Claim.

-This invention is a divisiony of my' copending application SerialyNo. 756,496, `filed December 7, 1934, and relates tothe art of casting metal, and particularly to that phase of the art concerned witheliminating and avoiding` imperfection in thearticles cast. More particularly, my invention concerns the elimination ofgblow holes, iissures, pipe and other objectionable flaws frequently found in the cast metal when l it has solidified. Although my invention may be us'ed in casting ingots of various metals, a con- ,venient example of its eiciency is illustrated by theexample of steel poured into ingot molds in the casting of ingots which later are to be l5 shapedin rolling mills. It has been customarypwhen casting steel lngots, to transfer the moltenmetalfromA the furnace or converter to a-large teeming ladle. 'Ihis ladle was then transported to thepuring oor and the ingot molds successively filled. When the metal had cooled and the mold had been removed from thereabout, an examination of the ingots thus formed usually revealed several defects. I l s A pipe would have formed adjacent the vertical axis oi the ingot, extending from the top downwardly, sometimes for/about half the depth of the entire ingot. `Oxidation of the exposed pipe surface prevented the metal from knitting properly into an integral piece when passed through the rolls I,of a mill. Hence, that portion of the ingot aected by the pipe had to be cut od and discardedf-a very wasteful loss of time and material, even though thediscarded portion could be remelted.

The inclusion of gas and iined would react with the hot metal to form a thin nlm, for instance anoxide, about the surface of the metal exposed to the bubbles.`A

of lcombined metal would also' prevent the opposite portions of the ingot from knitting under the rolling action, and thus leave defects i on the nished product. Y l 45 It has, in general, been an object of my invention to eliminate the `detects above mentioned from metal ingots. More specifically stated,'it is'an object of my invention to prevent the inclusin of objectionable gases and other foreign substances within the casting; it

' is also an object of my invention to eliminate shrinkage `defects, known in ingot casting -as Y It .will be apparentlfroni these objects-that t6 I contemplate employing apparatus comprising air bubbles in the' ingot was also harmful because the gas s`o con- ThiS (ci. 21e-is) my invention in conjunction with metals other than steel, although it4 is with that metal that \my invention is particularly concerned. lVIy invention will become more apparent from the 'accompanying description and the drawing in cluded therewith, the various salient features of the invention being set out in the claim.

In general, my invention comprises an appalratusto be used for removing' as much of the gas confined within the empty ingot molds as possible. It is by the achievement oi avpartial vacuum within the molds, while the metal` is being` poured, 'and both before and after pouring; if desired, that I accomplish the objects above enumerated. The highen the degree of vacuum obtainable, the better will be the results, and the more perfect the iinal castings.

When my invention is incorporated in the process of casting paratus carriedby theA teeming ladle, by means of which the desired vacuum within the mold is obtained. ThisA apparatus comprises a boxshaped enclosure, carried on the bottom of the.

the pouring nozzle. At its lower end, the box, which I call a vacuum box, is shaped to fit tightly around the edges of the upper end of an ingot mold.- When the box is seated properly on top of the ingot mold, there will thus be provided a relatively airtight chamber, comprising the interior of the vacuum box andthe interior of the ingot mold. It is the chamber so Cformed from which gli evacuate gas contained therein, and thus accomplish the objects of my invention.

Referring now to the drawing, Fig. l is an elevation, showing a teeming ladle with my vacuum box attached thereto, ready to be lowered against the trop of my empty ingot; Fig'. 2 isa transverse section through my vacuum box, showing the same secured to the ladle and resting on the top of transverse section ladle and surrounding through the construction of Fig. 2, as indicated by the line 3-3 on Fig. 2;

Fig. 4' is a horizontal section throughjthe lmodi- 4ilcation of Fig. 3,. as indicated by the line 4-4- the lower end of the nozzle used to pour the metal into the molds. This vacuum box as shown in Fig. 1 is fastened to the underside of a`teeming ladle L, which in turn is suspended by a pair of hooks h from an overhead traveling crane. Lying beneath the travel of 'the steel ingots, I provide an apan ingot mold; Fig. 3 ris a overhead crane is atrack 'r adapted to carry a series of cars C forming a train of molds, two of which molds M may be carried by eachcarf When the pouring operationtakes place, either the ladle L may b'e moved bythe crane along the train of mold cars or the train itself may be moved underneath the ladle, permitting successive ingot i'noldsJto be pou'red.

The desired degree -of vacuum may be obtained by means of a direct suction pump mechanism, by means of-which the air is directly withdrawn from within the space to be evacuated. Such a vpumping apparatus may be mountedon a suitable truck t adapted to be moved along the pouring oor with the ladle. On the truck t is carried a pump P preferably of the reciprocating type and which is driven by an electric motor. The hose H is used to transmit gas to the pump P by means of which direct evacuation of the ingot mold is produced.

A vacuum chamber is interposed between the teeming ladle and'the ingot mold to permit the Withdrawal of the air within the mold. This comprises a box I having outturned flanges I2 at the top and inturned flanges I3 at the bottom shaped to form a. rectangular box open at each end. 'Ihe outturned flanges I2 are riveted. or otherwise securely fastened to the underside of a ladle L in a position to enable the box to surround the discharge nozzle N of the ladle.

V.A suitable iirebrick lining I5 is provided for the box IIVand is supported on the inturned iianges I3 `of the bottom of the box.v As shown in Fig. 2, a partition I'I is formed, dividing the box into two sections, the ends of the partition terminating at flanges I8, which are riveted or otherwise securely fastened to adjacent faces of the sides of the box. The lower ends of the partition I'I are cut into segments of iiange; alternate segments of which are bent horizontally on respective sides of thepartitlon to support 4fire brick lining-20 on each side thereof.

It will be noted that the partition Il is so disposed within the vacuum box that one chamber is considerably smaller `than the other. The smaller of these chambers is provided with an exhaust pipe 22, securely fastened to the sides of the box and ommunicatingwith the interior through its opening 23 in the box and the rebrick. This pipe` 22` extends outwardly horizontally and provided with a screen 25 to bar the egress of solid particles from within the chamber to be evacuated.

`".'l'he screen 25 is made removable to readily permit the cleaning of the pipe 22. At its freecnd, this pipe 22 is provided with a coupling of any well-known form to allow a suction hose I-I to be fastened thereto and yet be readily removable when desired. hose H is fastened to the bayonet coupling of the pipe 22, which leads to a vacuum pump P used tol produce the degre of vacuum desired within the ingot mold cham ber. If desired, a baffle plateor similar construction may be interposed between the'pipe 22 and the vacuum to prevent any solid matter from en-v tering the pump chamber.

found that by employing a rabbeted upper end A in the ingot mold M as shown in Fig. 2, into which the vacuum `box may closely ft, it has been possible to provide aneiectual seal at this point.- If, for any reason, it should be desired to form a complete seal for the entirechamber, this may be accomplished by packing the junction of the various parts, as, for instance; the junction of the vacuum-box and the top of the ingot mold, with soft re clay 21.

It is not necessary to make the vacuum box removable from the underside of the ladle, since the latter is never'deposited directly on the ground, but rather is supported on a pair of trunnins, except during such period when various repairs are being made to it,jat which time the vacuum box can 40e removed if desired.

In operation, my invention may be used to effect'the' evacuation of ingot molds at variousv0 times. Preferably I choose to begin the evacuation before any metal is poured into the mold and continue the evacuation for some time after the mold has been completely iilled'.- This, however, is a matter of expediency and under certain conditions it might be found preferable to vary the evacuating action fora longervor shorter period of time, as best determined bythe requirements of a particular case, and depending upon what sort of metal was cast with the aid of the apparatus and the method embodied in my invention.

Other modes of applying the principle ofmy invention may be employed instead 'of the one explained, change being madeas regards the structure herein disclosed, provided themeans stated by any of the following claims or the equivalent of such stated means be employed.

vI therefore particularly point out and distinctly claim as \my invention:

, Incombination with a pouring ladle and a mold, a metal enclosure interposed therebetween to form with the mold a relatively airtight chamber; a metal partition' dividing said enclosure into two chambers, inturned flanges at' the bottom of said enclosure and partition, a heateresistant lining covering the interior of said enclosure and said partition and resting on said iianges, a tting secured to said enclosure 6 and leading tothe interior of said smaller chamber and adapted kto receive a hose connectionby which gas -is removed from .the said chamber.

l GEORGE W. HAZEY.

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