US2673380A - Apparatus for recovering excess molten metal - Google Patents

Description

March 30, 1954 F. A. WAGNER ETAL 2573.380

APPARATUS FOR RECOVERING EXCESS MOLTEN METAL Filed July 2 1951 2 Sheets-Sheet 1 In van 0715 Frederik/f .1 [Wagner March 30, 1954 F. A. WAGNER ETAL 2,673,380

APPARATUS FOR RECOVERING EXCESS MOLTEN METAL Filed July 2 1951 2 Sheets-Sheet 2 I we)? Z0215 Frederzbxtvi. Way her erz j z'erce Patented Mar. 30, 1954 APPARATUS FOR REGOVERING EXCESS MOLTEN METAL Frederick A. Wagner, East Lansing, and Albert D. Pierce, Lansing, Mich., assignors to Campbell, Wyant & Cannon Foundry Company, Muskegon, Mich, a corporation of Michigan Application July 2, 1951, Serial No. 234,784

3 Claims.

Our invention relates to improvements in apparatus for recovering excess molten metal from continuous casting operation. It has for one object to provide means for automatically recovering granulated and disposing of excess molten metal poured from a ladle in a casting operation.

In the usual casting operation where a pattern is packed in sand to form a mold and where thereafter a ladle of molten metal is presented to the mold either by movement of the ladle or the mold or both, there is always an excess of molten metal poured out. This excess backs up after the mold, the gates and the riser or risers have been filled and such excess molten metal spreads out over the top of the mold and is allowed to harden, being disposed of in the check out when the gates and risers are removed from the casting. Accuracy of measurement of the amount of metal supplied to the mold depends on the skill of the operator. He should stop pouring as soon as the riser is full so as to leave in the mold and in the riser a sufficient amount of metal to take care of shrinkage. 1

When it becomes essential as inconnection with the casting of iron linings centrifugally into a steel brake drum shell to get the right amount of metal into the shell, it has been customary in the past to provide a runner box associated with the spinning shell. Under these circumstances the runner box contains just the right amount of molten iron to make a proper lining and so molten metal is poured into th runner box until it overflows slightly and then later or immediately thereafter the runner box with the proper amount of metal is spilled into the rotating shell. In order that there may always be enough molten metal in the runner box, the box under ordinary circumstances is slightly overfilled and s means have been provided to catch the slight overflow. It has taken the form of the metal cup beneath the spout of the runner box and as the runner box is successfully presented to the pouring ladle, the overflow receptacle gradually fills up with the molten iron which solidifies after each pour. Periodically that box or receptacle must be cleared of the solidified iron or metal therein to keep it from overflowing over the floor and causing waste and danger. This of course is especially important in a situation which is characteristic of the manufacture of Centrifuse brake drums where a large number of runner boxes on a turntable are in continuous rotation being presented one after the other to the pouring spout of the ladle and so men have to be available all the time to clear the overflow from these small boxes which receive it from the runner box.

Then this hot iron must be handled and gotten out of the way and returned to the cupola or scrap pile as the case may be.

We propose to accomplish the granulation and cooling and recovery of the molten iron by providing beneath the point at which the metal is poured to the runner box a trough with a water jet so that the excess iron overflowing from the runner box will be discharged into the trough, quenched by the jet of water therein which results in some measure of granulation of the metal and be conveyed by the jet to a reservoir from which the chilled iron may be continuously withdrawn for other and final disposal. Under these circumstances there can be no splatter or splash, no danger to the operator and a continuous automatic discharge of the excess iron so that no man power is required at or immediately adjacent the pouring station to dispose of the excess iron.

Our invention is illustrated more or less diagrammatically in the accompanying drawings, whereins Figure l is a partial plan view of a casting machine including turntable, runner boxes and ladle;

Figure 2 is a section along the line 2--2 of Figure l;

Figure 3 is a section along the line 3-3 of Figure 1.

Like parts are indicated by like characters throughout the specification and drawings.

1 is a turntable. 2 is a housing containing a chuck, a mold carried thereby and means for spinning them. 3 is a door for the housing. 4 is a rotatable runner box extending through the door into the housing, in register with the mold, and adapted when rotated to pour its contents into the mold.

5 is a dam and 6 a chute over which molten metal overflowing from the runner box may flow. 7 is a trough below the turntable in register with the chute and adapted to receive the molten metal as it falls by gravity therefrom. 8 is a nozzle adapted to discharge a jet of water downwardly along the trough l, to impinge upon and contact the molten metal as it pours into the trough.

9 is a reservoir adapted to receive the Water and chilled and granulated metal from the trough 7. id is a conveyor adapted to recover the metal from the reservoir. H is a water outflow. I2 is a ladle adapted to discharge molten metal into the runner box. I3 is a trough through which molten metal from any suitable source is fed to the ladle. I4 is a lever by which the operator may cause the ladle to periodically discharge its contents into the runner box.

The chilled metal shot resulting from the impact of the jet of water from the nozzle 8 which is carried down to the reservoir 9 is recovered by the bucket container l and thereafter screened. Ihus shot particles of such size and shape as, to be useful are used as shot in the foundry, other particles being returned to the cupola.

It will be realized that whereas we have described and illustrated an operative device, still many changes in the size, shape, number and arrangement of parts might be madewithoutde: parting materially from the spirit of our invention. We wish, therefore, that the showing be taken as in a large sense diagrammatic rather than limiting us to the precise showing.

The use and operation of our inventionare as follows:

Our invention is particularly adapted for use in connection with the casting oi cast iron liners.

for steel brake drums for automotive vehicles and the like wherein a steel shell isheated, rotated at high speed and wherein a, measured amount of molten metal is fed into the drum and held by centrifugal force against the inner periphery thereof until it cools and a permanent bond is eijected between the steel; shell and the cast iron liner.

Under these circumstances, it is of the utmost importance that neither too much nor too little molten metal be supplied to the shell so means must be provided for accurately measuring the amount 0t metal fed to the mold, or in this case the shell.

The runner box which projects into register with the shell, is exposed so that molten metal may be poured into it. If the foundryman when he pours could always pour just enough molten metal into the runner box to fill it exactly, he would get a good lined drum. But he never can be sure of doing just that so the runner box is provided with a dam over which some excess molten metal may flow. The less molten metal thatiruns out of the runner box, the better to be sure but in high speed operation, the safe thing is for the foundryman to pourin just enough toget a slight overflow. Ehat'overflow runs out over the dam, falls freely into the trough, is there brought in contact with the jet or current of water and since it is falling freely asjailiquid it mixeswith the liquid in the trough, is'chilled and is more orless granulated and carried along the floor of the trough to the storagereservoir whence it can be removed and returnto the cupola or to the scrap pile for reuse.

As the falling stream of molten metal strikes the violently projected current of water from the discharge nozzle, the impact of the water against the falling metal chills and breaks the metal up and forms chilled shot. This shot is. sub:- sequently screened and used as chilled cast iron shot in the foundry. Thus the Waste molten metal pouredyin excess necessary to be wasted in order to. insure the proper amount of: metal in the mold is not lost but is usedtofurnish at least a part of the chilled iron shot used in other operations in the foundry. Of course, any particles, and there maybe a few of unsatisfactory size or shape for use as chilled shot, can be returned to the cupola.

Some of the efiect so far as disposing of the molten metal is concerned could be obtained by merely dropping the molten metal into a stream of water. This, would, dispose, of the molten metal, would carry it to the reservoir and pro vide for its recovery as more or less granular materia1 but when the high velocity, high pressure water jet is caused to strike directly on the stream of; molten metal, this useful shot is formed.

W c a 1. In combination, a receptacle adapted to receive and hold molten metal, an overflow chute associated therewith, means for moving the discharge end of the chute along a curved path, a trough below and generally tangent to the curved path of the discharge end of the chute, a pouring ladle above and in pouring register with the receptacle approximately at its point of tangency to'the path of; the discharge end of the chute, means for discharging a jet of quenching liquid along and above the floor of the trough for impingment upon a stream of overflow molten metal flowing from the discharge end of the chute toward the trough.

2. In combination, a measuring box adapted to receive and hold a measured amount of molten metal, an overflow chute associated therewith,

means for moving them alonga curved path, a downwardly inclined trough below, and generally tangent to the path of, the chute, a pouring ladle above and in register with the measuring box at the point of tangency of the path and box, means for discharging a jet of quenching liquid along the trough forimpingement as a jet, with an overflow discharge of molten metal through the chute toward the trough, means for recovering solids from the lower end of the trough.

3. In combination, a receptacle adapted to receive and hold molten metal, an overflow chute associated therewith, a chamber open at the top below the overflow chute, a. pouring ladle above the; chute in register with the open top of the chamber, means for moving the receptacle into register with the chamber and the pouring ladle andmeans within the chamber for discharging a jet of quenching liquid 'against the stream of overflow molten metal-fiowing downwardly from the discharge end of the chute.

FREDERICK A. WAGNER.

ALBERT D. PIERCE.

References Cited in the file of this patent UNITED STATES PATENTS OTHER REFERENCES The Foundry, Apr-i1. 1932, pages 40, 4.1, 42 and 86.

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