US3709286A

US3709286A - Continuous-casting mold with thin-walled copper liner

Info

Publication number: US3709286A
Application number: US00085848A
Authority: US
Inventors: J Bower
Original assignee: United States Steel Corp
Current assignee: AG Industries Inc Pennsylvania
Priority date: 1970-11-02
Filing date: 1970-11-02
Publication date: 1973-01-09
Anticipated expiration: 1990-01-09
Also published as: BR7107229D0; ES201009Y; DE2154101A1; ES201009U; AT315402B; AU3498171A; BE774651A; FR2112384B1; GB1363678A; CA953874A; IT940094B; AU456811B2; ZA717100B; RO60296A; FR2112384A1; NL7114971A

Abstract

A continuous-casting mold in which the steel backing plates are fastened to the copper liner with studs welded to the liner. The welded construction enables a thinner-walled liner to be used and affords better resistance against heat distortion and thermal stresses. The studs may be welded directly to the liner or to stainless steel strips which in turn are welded to the liner.

Description

United States Patent 91 Bower, Jr.

[ 1 Jan. 9, 1973 [54] CONTINUOUS-CASTING MOLD WITH T HIN-WALLED COPPER LINER [75] Inventor: John E. Bower, Jr., Monroeville Borough, Pa.

[73] Assignee: United States Steel Corporation [22] Filed: Nov. 2, 1970 i [21] Appl. No.1 85,848

[52] US. Cl ..164/283, 249/135 [51] Int. Cl. ..B22d 11/02 [58] Field of Search ..164/273 R, 283; 249/135;

[56] References Cited UNITED STATES PATENTS Kiefer ..220/63 R 3,618,658 ll/1971 Gallucci ..164/283X FOREIGN PATENTS OR APPLICATIONS 962,259 7/1964 Great Britain ..164/283 1,191,833 5/1970 Great Britain ..164/273 Primary ExaminerRobert D. Baldwin Attorney-Walter P. Wood [57] ABSTRACT A continuous-casting mold in which the steel backing plates are fastened to the copper liner with studs welded to the liner. The welded construction enables a thinner-walled liner to be used and affords better resistance against heat distortion and thermal stresses. The studs may be welded directly to the liner or to stainless steel strips which in turn are welded to the liner.

5 Claims, 4 Drawing Figures PATENTEDJAN 9 I975 SHEET 2 [IF 2 lNVE/VTOR JOHIVE BOWL R JR.

Attorney CONTINUOUS-CASTING MOLD WITH THIN- WALLED COPPER LINER This invention relates to an improved mold for continuously casting metals.

A conventional continuous-casting mold is a doublewalled open-ended sleeve. The inner wall or liner usually is formed of copper to furnish maximum thermal conductivity, and the outer wall or backing is formed of steel plates to furnish mechanical strength. Liquid metal is poured into the top of the mold and a partially solidified casting emerges continuously from the bottom. Channels are formed between the backing and liner through which water circulates to cool the liner and assist in solidifying the casting. The channels may be machined into either the copper liner or steel backing, but preferably into the latter to conserve copper which is more costly. It is of course necessary to fasten the backing plates and liner together. I-Ieretofore the practice has been to drill and tap openings in the outside faces of the copper liner and thread studs, usually steel, into these openings. The studs extend through mating openings in the backing plates and carry nuts which hold these plates in place. The conventional construction necessitates the use of a relatively thick-walled liner to afford support for the studs, but this creates an undesirable stress pattern, as well as utilizing a large quantity of copper.

An object of my invention is to provide an improved continuous-casting mold which enables me to diminish the wall thickness of the copper liner, thus affording a better stress pattern and using less copper.

A more specific object is to provide an improved mold in which I weld the studs to the copper liner, either through the use of intermediate strips or directly.

In the drawings:

FIG. 1 is a. simplified exploded perspective view of one form of mold constructed in accordance with my invention;

FIG. 2 is a vertical section through the double-wall of the mold showing a modification;

FIG. 3 is a section similar to FIG. 2, but showing another modification and FIG. 4 is a horizontal section through the double-wall of the mold showing a further modification.

FIG. 1 shows a continuous-casting mold which includes a copper inner wall or liner l and an outer wall or backing formed of steel side plates 12, end plates 13 and corner bars 14. The liner illustrated is of one-piece welded construction and has a relatively thin wall, preferably about inch thick. A plurality of vertical channels 15 are machined in the inside faces of the side and

end plates

12 and 13, leaving ribs 16 between channels. The channels serve as passages for circulating water to cool the liner. The lower and upper ends of the channels have water inlets and outlets, which are arranged in the usual fashion but are not shown since they are not involved in the present invention. A plurality of shallow vertical channels 17 are machined in the outside faces of liner at locations opposite ribs 16. I weld stainless steel strips 18 in these channels. The strips preferably are about 3/16 inch thick and of a maximum width of about 1 inch, and in this embodiment are continuous from the top to the bottom of the liner. To each strip I weld a row of vertically spaced studs 19, preferably also of stainless steel. Preferably I emplo an electron beam to weld strips 18 in channels 17 an a conventional welding gun to weld studs 19 to the strips. The side and

end plates

12 and 13 have openings 20 through their ribs 16 to receive the studs. Nuts are threadedly engaged with the ends of the studs outside the plates to hold the parts assembled. I attach the corner bars 14 with threaded connectors (not shown) to afford handling and torsional rigidity to the assembled mold.

FIG. 2 shows a modification in which the stainless steel strips are in discontinuous sections 23 with gaps 24 therebetween. The nuts on the studs are countersunk in the outside of the plates. The same countersunk arrangement also can be used with the embodiment shown in FIG. 1. In other respects the embodiment of FIG. 2 is similar to that of FIG. 1; hence I have not repeated the description.

FIG. 3 shows another modification in which I weld studs 26 directly to the copper liner 27.

FIG. 4 shows another modification in which I apply the principles of my invention to a four-piece copper liner. The liner includes end members 29 which abut the inner faces of side members 30. This construction enables the liner to be adjusted to cast different sizes of product, as known in the art.

In each instance I use a thin-walled liner, which not only conserves copper but affords better resistance against heat distortion and thermal stresses than a liner with thicker walls. The

stainless steel strips

18 or 23 have approximately the same coefficient of expansion as the copper liner. The strips of FIGS. 1 and 2 distribute the load on the studs over a greater area of the liner than directly welded studs of FIG. 3, but the latter offers better heat transfer. The discontinuous strips of FIG. 2 allow greater flexibility of the mold and increase the capacity of the mold to absorb thermal distortions over the continuous strips of FIG. 1.

I claim:

1. In a continuous-casting mold which includes a relatively thin-walled copper liner of a thickness of about inch, steel backing plates outside said liner and having vertical channels in their inside faces for circulating water and ribs between channels, and means fastening said plates to said liner, the improvement in which s'aidfastening means-includes stainless steel strips, a plurality of studs welded to each of said strips, and nuts threadedly engaging said studs, said liner having vertical channels in its outside face opposite said ribs, said strips being welded in said second-named channels, said studs extending through openings in said ribs, said nuts being located outside said plates.

2. A mold as defined in claim 1 in which said strips are continuous from the top to the bottom of said liner.

3. A mold as defined in claim 1 in which said strips are in sections with gaps between sections.

4. A mold as defined in claim 1 in which said liner is of one-piece welded construction.

5. A mold as defined in claim 1 in which said liner is of four-piece construction with end walls abutting side walls.

Claims

1. In a continuous-casting mold which includes a relatively thin-walled copper liner of a thickness of about 3/8 inch, steel backing plates outside said liner and having vertical channels in their inside faces for circulating water and ribs between channels, and means fastening said plates to said liner, the improvement in which said fastening means includes stainless steel strips, a plurality of studs welded to each of said strips, and nuts threadedly engaging said studs, said liner having vertical channels in its outside face opposite said ribs, said strips being welded in said second-named channels, said studs extending through openings in said ribs, said nuts being located outside said plates.