US1710534A - Process for casting hollow bodies - Google Patents

Description

April 23, W29. H. E. FIELD PROCESS FOR CASTING HOLLOW BODIES Filed Sept. 1926 al touwq Patented Apr. 23, 1929.

UNITED STATES PATENT OFFICE.

HERBERT E. FIELD, OF WHEELING, WEST VIRGINIA, ASSIGNOR TO WHEELING MOLD & FOUNDRY COMPANY, OF WHEELING, 'WEST VIRGINIA, A CORPORATION OF DELAWARE.

PROCESS FOR CASTING HOLLOW BODIES.

Application filed September 2, 1926. Serial No. 133,190.

This is an improvement in a method'and mold for castihg hollow bodies, and its main object resides in the improved method.

I have discovered that hollow bodies can be cast by utilizing as a center eorea metal or alloy having a lower melting point than that of the metal' composing the hollow body, whereby the metal having a loW melting point melts and is conducted away, leavin the hollow cast body.

llly improved process consists in casting either iron or steel around certain other metals or alloys of such metals, the latter having such heat conductivity and low melting point that when the iron or steel 01' alloy of either is poured around it, that the center low melting point metal conducts the heat so rapidly from the iron or steel that it will immediately set around the center metal or alloy and form a sufficiently thick wall of iron or steel and the softer metal will afterwards also melt and be conducted away, leaving a clean hole that had previously been occupied by the metal of high conductivity and low melting point.

In practicing my improved method I utilize a mold of suitable shape and support in the center of said mold metal or alloy having a lower melting point than the melting point of the cast hollow body. This low melting metal or alloy may be composed of a solid body; or only a tubular body wit-h a center of steel or other metal, or may consist of a hollow tubular member of metal of low melting point sufliciently heavy to operateto cause a crust on the inner side of the metal to be cast after which the tube will melt and be led away, leaving a clean center hollow casting.

I have usually used in practice a brass center member which I find has sufiicient conductivity of heat, and is of a sufiiciently low melting point that when the cast metal of higher melting point is poured around it, that it will act to form a crust on the surrounding cast body and will melt and be conveyed away, forming a clean center for the cast body.

In the accompanying drawings:

Figure 1 is a vertical central sectional view of a mold for carrying out my improved process, the metals being shown in position therein and a tube that is very thin.

Figure 2 is a similar view showing the 'same is likewise true of the sump tubular metal of low melting point heavier than is shown in Figure 1.

Figure 3 is a similar view showing the metal of low melting point formed in a solid bar.

Figure 4 is a vertical sectional view of my improved mold for casting hollow bodies.

In carrying out my improved method, I have a mold 1 that has a bot-tom or stool portion 2,. this stool havinga central openlng 3 that communicates with a sump 4. A top portion 5 is provided, and this top has a suitable central opening 6 made therein. The top may be composed of sand and the Passing through the top part 5 is a suitable metal bar 7 composed of steel, iron or alloys thereof, which passes through the opening 6 and extends downwardly through the opening 3 formed in the stool, and preferably through the stool and slightly into the sump portion 4. This rod 7 is made of a diameter less than the diameter of the opening 3 whereby there is a space around the rod. Surrounding this rod 7 is a thin coating of brass 8 as shown in Figure 1 or a thicker coating as shown in Figure 2. The casting 9 is poured into the mold 1 in any suitable manner, for instance through the openings 10 which communicate with the interior of the mold. In Figures 1 to 3 inclusive of the drawings, all of the metals are shown in position in the mold, while in Figure 4 the metal of low melting pointhas melted and has escaped through theopening 3 into the sump 4. The described process and the mold may be varied somewhat so long as the variations do not depart from the idea above described. For instance in carrying out the method it is only essential that the metal which forms the center of the casting shall be of a lower melting point than the metal of the casting, and as to the mold, it should be provided with some means of escape for the metal that is melted by the pouring around it the metal forming the casting 9.

Therefore variations may be made so long as they come within a fair interpretation of the appended claims and without departing from the spirit and scope of the invention.

Having thus described my invention, what I claim .and desire to secure by Letters Patent of the United States is:

1. The improved method of automatically casting hollow bodies and causing the core to flow from the mold, consisting in supporting centrally in themold a metal core having a sufficiently lower melting point than the melting point of the metal to be cast thereabout, then pouring the metal around the core to cause it to first set and then melt and automatically flow from the mold, whereby the said core will cause the metal being cast to set to shape and then automatically melt and flow from the said mold.

2. The improved method of automatically casting hollow bodies and causing the central core to melt and flow from the mold consisting in providing a suitable mold and sustaining centrally within the mold a metal-core consisting of an alloy, then pouring around the alloy core a metal of sufiiciently higher temperature than the alloy core to set around the core and then melt the said core which flows automatically from the mold.

3. The improved method of automatically casting hollow bodies and causing the central core to melt and flow from the mold consisting in providing a suitable mold and sustaining centrally within the mold a metal core consisting of brass,then pouring around the brass core a metal of sufiiciently higher temperature than the brass core to set around the core and then melt the said core which flows automatically from the mold.

In testimony whereof I hereunto afiix my signature.

HERBERT IE. FIELD.

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