US1564369A - Method of casting copper - Google Patents

Description

Patented Dec. 8, 192 5. a V

UNITED STATES 1,564,369 PATENT OFFICE.

LEONARD SHIPLEY, vOIE DUNDALK, MARYLAND, ASSIGNOR T0 AMERICAN SMELTING AND REFINING COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NEW JERSEY.

METHOD OF CASTING COPPER.

No Drawing. 7

To all 'w' ho'rn, it may concern-:-

Be it known that I, LEONARD SHIPLEY, a citizen of the United States, and resident of Dundalk, in the county of Baltimore and State of Maryland, have invented certain new and useful Improvements in Methods of Casting Copper, of which the following is a specification.

This invention relates to the casting of copper in bars, ingots, slabs and various other shapes. 3 y

The slabs and other shapes cast according to present methods have always had a rough or irregular upper surface, full of ridges and furroughs, so much so that the products in fact have been classified by the characteristic appearance of these ridges. Thus, if the ridges are close together, the copper is said to be close set and coarse set if the ridges are further apart. For certain purposes, su h as the drawing of fine wire and rolling of thin copper sheets, this so-called set becomes obj ectionable, causing cracks and imperfections to run through the finished product.

Another objectionable feature I has been the so-called pitch of the upper surfaces of the cast ingots or slabs, these being classitied as of high pitch if of a convex surface, fiat pitchif level and low pitch if concave;

The objects of this invention are to overcome and eliminate these imperfections or irregularities and to produce a cast copper product having a substantially smooth re'gular upper surface free of imperfections which might run through the subsequently formed products.

I have discovered that the objectionable unevenness which has heretofore been characteristic of the copper castings is occasioned by the formation of a film of oxide on the top surface which forms a wavy or ridgelike structure as the metal contracts and gives up absorbed gases under the cooling influence of the atmosphere.

These results are prevented in this invention by covering the molds immediately after the molten copper is poured and keeping them covered until the copper sets.

In the present practice of the invention, the molten copper is poured from the ladle into the molds of the casting machine, as usualfand as soon as each mold is filled,

it is immediately covered to shut off access.

Application filed June 20, 1924. Serial No. 721,191.

vent direct contact ofthe atmosphere with the copper. A clearance of one-half inch or even more between the sides of the mold and the cover is permissible in practice since it is desirable to allow speedy escape of the occluded gases. j

After the copper sets, which requires from about three to seven minutes, depending upon the thickness of the .bar and various other factors, the cover is removed from the mold and the casting is cooled by water spray or otherwise treated in the usual manner.

By covering the copper immediately after it is poured and while still in amolten condition, the formation of the 1 heretofore characteristic rough surface of the casting presents as smooth a surface as the sides which lie in contact with the mold walls. A superior product is thus produced, which can be drawn, rolled or otherwise treated with certainty of the results being uniform and free from imperfections.

The absence of the characteristic set or pitch also makes the casting solid and of the same density throughoutits dimensions. The appearance of the new slabs or castings also is better, making them more desirable and marketable products.

What is claimed is:

1. The method of casting copper shapes,

the molds closely enough to prevent free contact of atmosphere while permitting escape of the occluded gases and during a time sufficient to prevent surface oxidizatinn. rapid cooling and sudden degasificat-ion of the copper. I v

2. In the casting of copper in open molds, a step which includes covering the open molds containing the molten copper until the molten metal has set.

3. The method of producing cast copper shapes with smooth top surglaces Whichinpouring the molten metal'in open molds, 10 eludes the step of covering the molds imcovering the molds to-prevent free access of mediately after pouring the molten metal air tothe molten metal, uncovering the mold thereinto closely enough to prevent free a(: after the metal has set and then cooling the cess of air thereto but allowing for escape of solidified shape.

occluded gases and for a'time sufiicient for Siqned at Baltimore in the county of 15 the molten metal to set. Baltimore and State of Maryland this 6th 4. The method of casting copper shapes day of June A. D. 1924:. v with smooth top surfaces which comprises LEONARD SHIPLEY.