US781914A - Manufacture of chilled castings. - Google Patents

Description

PATENTED FEB. 7, 1905.

J. S. SEAMAN.

MANUFACTURE OF GHILLED GASTINGS.

APPLICATION TILED HAY 23. 1904.

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Patented February '7, 190 5.

IJNTTED STATES PATENT Trice.

JOSEPH S. SEAMAN, OF PITTSBURG, PENNSYLVANIA.

MANUFACTURE OF CHILLED CASTINGS.

SPECIFICATION forming part of Letters Patent No. 781,914, dated February 7, 1905.

Application filed May 23, 1904. Serial No. 209,310-

To (all whom it In/(1ycon/c772,.-

Be it known that LJosnrir S. SEAMAN, a citizen ofthe United States,residing at Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented or discovered certain new and useful Improvements in the Mannfacture of Chilled Castings, of which improve ment the following is a specification.

As is well known by those skilled in the art, not only the depth, but also the hardness of the chill on a roll or other article, depends upon the rapidity with which heat is carried away from the molten metal and the etiicient persistence of this cooling action. The contraction of the molten metal during cooling and solidification and the expansion of the chill-ring when heated produce such a separation of the chill-ring and the cast metal that the former will not act by conduction to cool the cast metal, and the heat retained in the casting by reason of the heating of the chillring and its failure to carry away the heat will produce an annealing or softening etlcct on the chill produced by the first contact of the molten metal with the ring.

The present invention has for its object the employment of a chill-ring which will act effectively during the initial cooling of the metal, at which time the contraction is greatest, and the substitution of a second and preferably slightly smaller chill-ring for the first, whereby the article will be subjected to a secondary chilling act-ion, which will be more continuing than the first chilling, and all annealing or softening action avoided.

The invention is hereinafter more fully described and claimed.

In the accompanying drawings, forming a part of this specification,Figure 1 isa sectional elevation of a mold for casting rolls, a casting being shown in position in the mold; and Fig. is a similar view showing the parts after the first chill-ring has been removed and another ring placed in position.

In the practice of my invention the mold v as regards the drag '1, ch1ll-r1ng2, and runnor 3 are constructed in the usual or any suitable manner. The cope st may be constructed as is common in the art to permit the chill-ring being drawn up outside of it, or, and as is preferable, the cope is made in two vertical sections separated from each other by a thin metal ring 5. The matrices for the rollneck wabbler and sinker-head are formed of clay within the ring 5, which has an external diameter less than the internal diameter of the chill-ring 2. The space between the ring 5 and the cope-frame at is filled witha material such as sand, which will not cake or harden when heated.

After the mold has been formed in the manner stated the metal is teemed in through the sprue, as is customary. The molten metal on coming into contact with the (jllill'l'ilig' is cooled and hardened. As the heat is conducted away from the metal by the chill-ring the latter will expand by reason of the heat absorbed,aml the casting will contract. These opposite movements will so separate the casting and the chill-ring, that the latter will no longer act with the desired cflicieucy. This loss of eliiciency is due not only to the separation of the casting and chill-ring. but also to the heating of the chill-ring by the molten metal, so that the chill formed by the first contact of the molten metal with the chill-ring will be softened by the annealing of the retained heat. As soon as this separation of the casting and the chillring has taken place and the shell of solidified metal forming the exterior of the casting has becomesuilicicntly rigid to prevent dcformation of the casting when the chillring is removed the cope-frame and the material bctween it and the ringo are removed and the chill-ringZ stripped oti the casting. A second ehillring 2, preferably of slightly less diameter than the ring 2, is slipped down onto the casting. As this ring is cold and will come into direct contact with the surface of the casting, a second chilling action will occur and will continue for a longer time, as the contraction of the casting at this stage is not as rapid as at first, nor will the chill-ring 2 be heated and expanded as rapidly.

1 claim herein as my invention 1. As an improvement in the art of manufacturing chilled castings the method herein described which consists in casting the metal against a chill, removing the latter and subremoving the chill-ring and substituting an-,

stituting' a second chill therefor, substantially as set forth.

2. As an improvement in the art of manufacturing chilled rolls, the method herein described Which consists in casting the molten metal in contact with a chill-ring, permitting the formation of a rigid shell on the casting,

other therefor, substantially as setforth. IO

In testimony whereof I. have hereunto set my hand.

JOSEPH S. SEAMAN. Witnesses:

DARWIN S. WOLCOTT, F. E. GAITHER.

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