US2428660A

US2428660A - Water-cooled slab mold

Info

Publication number: US2428660A
Application number: US584614A
Authority: US
Inventors: Ernest C Falk; Robert S Storrs
Original assignee: American Brass Co
Current assignee: American Brass Co
Priority date: 1945-03-24
Filing date: 1945-03-24
Publication date: 1947-10-07
Anticipated expiration: 1964-10-07

Description

Oct. 7, 1947- ac. FALK ETAL WATER-COOLED SLAB MOLD Z SheetS-Sheet 1 Filed March 24, 1945 5 s 5 r E W n m 4 pm Patented Oct. 7, 1947 UNl'l'ED STATES PATENT. orr ce wA'rEn-coomn SLAB MOLD Ernest c. Falk and Robert s. Storrs, rel-damn,

Conn, assignors to The American Brass Company, a corporation of Connecticut Application March 24, 1945, Serial No. 584,614 7 2 Claims. 1

This invention relates to water-cooled or chill slab molds, and more particularly to molds of the type described in Junker U. S. Patent No. 1,615,086. Molds of this type are extensively used for casting slabs of metal, such as copper-bearing alloys, which are subsequently reduced to sheets by rolling.

In general, water-cooled slab molds of this type comprise a stationary mold back and a complementary or mating mold front hinged to the mold back and capable of being swung through an arc of 90 or more. When closed, the mold back and front provide a rectangular mold cavity-having faces and sides of good heat conductivity, usually plates of copper. The mold faces and usually the mold sides are in contact with circulating water, or other suitable cooling medium, flowing through appropriately provided compartments. In our copending patent application Ser. No. 522,459, filed February 15, 1944, we have disclosed an improved construction of cooling compartment, for the metal frames of cooled slab molds, comprising longitudinal and transverse ribbing forming a plurality of vertical channels with a series of vertically spaced pockets, which impart a very active swirling action to the upwardly flowing cooling medium. I

The present invention is an improvement upon the cooling compartment structure disclosed in our aforesaid application, and a continuationin-part of our companion patent application Ser. No. 522,460, filed February 15, 1944.

In the course of our development of and experience with cooled molds embodying the inventions of the aforementioned applications, we have found it advantageous, if not in fact necessary for satisfactory and economical commercial practice, to provide a heat-resistant packing between the side and end walls of the recessed metal frame and the adjacent mold face plate (and cooperating clamp bar when present). Although this packing is relatively thin (usually from to A; inch thick), we found that where the walls of the frame and the outer. surfaces of the longitudinal ribs were machined to-lie in exactly the same plane, the mold face plate, although of heavy copper, ultimately assumed a slightly concave contour and the cast slabs were consequently thicker at the center and gave trouble in the initial rolling passes. Although it appeared incredible that any conditions of casting could even so slightly distort the planar surface of the mold face plate, we decided to ascertain it slightly lengthening the longitudinal ribs would have any 2 with the provision of such elements the planar surface of the mold face was satisfactorily preserved.

Our present invention is based on the foregopressed packing) beyond a parallel plane in which lie the outer surfaces of the side and end walls of the frame. The foregoing and other novel features of the invention will be best understood from the following description taken in conjunction with the accompanying drawings, in which: Fig. 1 is a transverse section (section line l-l of Fig. 2) of a five-channel mold embodying the inventions of our aforementioned applications and provided with the improved recessed metal frame of the present invention,

Fig. 2 is a front elevation of the recessed metal frame of the mold back, I

Fig. 3 is a longitudinal section of the frame on the section line 3-3 of Fig. 2, and

Fig. 4 is an enlargement of one end of Fig. l. The mold illustrated in the drawings comprises a stationary mold member A (mold back) and a complementary mold member B (mold front) pivotally connected together by links in and pins ll so that the mold front B can be swung to and fro to close and open the mold. Thus, the mold front is pivotally mounted at one side of the mold back. Transverse spaced yokes mounted in brackets IS on the outer face of the mold front B. A link [4 is pivoted to each end of each yoke. The outer or free end of each link I4 has a head l5 adapted to operatively engage slotted lugs It on the sides of the stationary mold back A. When the mold is closed and the heads i5 operatively engage their respective slotted lugs I6, the mold members A and B are clamped together by turning the bolts I1, screw-threaded in central bosses I8 of each yoke and pressing against aligning wear plates I!) on the outer face of the mold front 3.

The stationary mold back A comprises a rectangular metal frame 20 and a rolled copper plate or mold face 2| appropriately secured therebeneficial effect upon the troublesome distortion to. The frame 20 is recessed or hollow to proof the mold face plate. Accordingly, we extended the longitudinal ribs of the recessed frame a distance approximate the thickness of the compressed packing by placing hairpin-like elements vide when covered by the plate 2| a channelled compartment for the cooling medium, such as water. The movable mold front B similarly comprises a rectangular metal frame 22 and a of sheet brass over these ribs, and found that rolled copper plate or mold face 23. While it desired number of longitudinal ribs.

of iron, they may be made of welded steel or in any other appropriate manner or of other suitable metal. The-mold face plates 2| and 23 are operatively secured to their

mating frames

20 and 22, respectively, by longitudinal clamp bars 24, permitting expansion and contraction of the plates, as particularly described and claimed in our aforementioned application Serial No. 522,- 460. Each longitudinal side of the copper plates 2| and 23 has a recessed shoulder 25 adapted to be engaged by a cooperating or mating shoulder on the clamp bar. The clamp bars 24 are secured to the side walls of their respective frames (20 and 22) by round headed bolts 26 fitting in counter bored holes in the clamp bars and registering holes in the sidewalls of the frame. The mold sides are formed in two sections consisting of a mold side bar 21 having a tongue and groove connection 28 with a backing bar 29, as particularly described and claimed in our aforementioned patent application Ser. No. 522,- 460. Each backing bar 29 is securely held against the adjacent clamp, bar 24 by round headed bolts 30 fitting in counter bored holes in the backing bar and extending through registering holes in the clamp bar. into registering holes in the side walls of the frames. It is to be understood that the mold faces 2| and 23 may be secured to their mating frames in any other appropriate manner, as for example by the heretofore customary bolts as described inour aforementioned application Ser. No. 522,459, and similarly the mold sides may be boltedto the frames as described in that application. The recessed compartments for the cooling.

medium in the

frames

20 and 22 are provided with the characteristic longitudinal and-transverse ribbing disclosed and claimed in our aforementioned application Ser. No. 522,459. Thus, each

frame

20 and 22 has a series of spaced longitudinal or vertical ribs 3| dividing the recess in the frame into a plurality of vertical channels. The mold illustrated in the accompanying drawings has four such longitudinal ribs dividing the recess into five vertical channels, but it is to is now our preferred practice to cast the frames be understood that the frames may have any Each of the five vertical channels has a series of vertically spaced transverse horizontal ribs 32 forming relatively deep pockets in the vertical channels formed by the longitudinal ribs 3|. The width or depth of the longitudinal ribs 3| is substantially the same as the depth of the recess in the frame, while the width or depth of the transverse ribs 32 is less than the depth of the recess in the frame, except as hereinafter particularly specified. In other words, the longitudinal ribs 3| extend from the back wall of the frame 20 (and 22) into contact with the adjacent mold face, while the transverse ribs 32 extend from the back wall of the frame to within a short distance of the mold face and thereby permit upward flow of the cooling medium through the spaces (passages) between the transverse ribs and the mold face.

The vertical ribs 3| have transverse openings 33 at their bottoms and transverse openings 34 at their tops providing communication between the channels. The thus-communicating channels above the uppermost transverse ribs 32 form a transverse outlet manifold communicating with the open top of a conduit or standpipe 35 positioned in one of the vertical channels. The

lower end of the standpipe 35 extends through 7 frame 20. The lowermost transverse ribs 32' are of substantially the same depth as the recess (extending from the back of the frame into contact with the mold face), and the communicat channels below these lowermost transverse ribs form a transverse inlet manifold communicating with an inlet pipe (or opening) 31 for cooling medium; Each lowermost transverse rib 32' has a vertical slot or opening 38 graduated in size in accordance with their distance from the inlet pipe 31 in order to equalize the pressure and flow of cooling medium to each of the five vertical channels, as more particularly explained in our aforementioned application Ser. No. 522,459. The

frames

20 and 22 may advantageously bepatent application Ser. No. 584,613, filed March 24, 1945, wherein a transverse partition divides one, or more if desired, of the vertical channels into a front cooling channel and a rear discharge channel, the latter replacing the standpipe 35. The inlet and outlet pipes for the cooling medium may be variously positioned.

The outer surfaces of the side walls 39 and end walls 40 are machined to lie in a common plane indicated by the dotted line a: in Fig. 3. In accordance with the present invention, the outer end surfaces of the longitudinal ribs 3| are similarly machined to lie in a common plane, indicated by the line y in Fig. 3,. parallel with and extending a small fraction of an inch beyond the plane :0. Additionally, the transverse ribs 32 of the two outer vertical channels are of the same depth as the longitudinal ribs for a short portion (4|) of their width immediately adjacent the side walls 39. Accordingly, over this smallpart (4|) of their width, the outer end surfaces of the transverse ribs 32 'of the two outside vertical channels are machined to lie in the common plane 1 of the outer end surfaces of the longitudinal ribs.

are similarly machined to lie in the common plane 1/.

In assembling the mold back and mold front, a sheet of packing 42 is cut to cover the outer surfaces of the side and end walls (39 and 40), and holes are punchedin the packing registering with those in the side and end walls. The packing is then interposed between the outer surfaces of the side and end walls and the adjacent surfaces of the mold face plate and cooperating clamp bars, and compressed therebetween by the bolts 26, and the customary bottom and top bolts.

We have found that the packing 42 is more uniformly and satisfactorily compressed when the clamp bar 24 is provided with a longitudinal rib 43 near the outer edge of its surface adjacent the side wall 39. Over the greater part of its width, the surface of theclamp bar 24 adjacent the side wall 39 lies substantially in the plane 1/, and over the remainder of its width the rib 43 projects to the plane 0:. The rib 43 thus contacts with the adjacent side wall 39 and serves to confine the packing 42 and also promotes uniform clamping of the copper face plate as-well as uniform compression of the packing when the bolts 26 are tightened. The extended parts 4! of the transverse ribs also form spaced restraining shoulders for the packing.

The packing 42 is heat resistant and may be composed principally ofasbestos, good quality rubber, cork or the like. The packing should also be of a character that will minimize friction and factilitate movement of the mold plate with respect to the frame. Various satisfactory types of service packing are available for the purpose. Sheet packing is available 'inany thickness required. With sheet packing having an initial thickness of 1 5 inch, the common plane (1/) of I the outer end surfaces of the longitudinal ribs 31, the transverse ribs 32 and the parts ll of the other transverse ribs will extend about 0.040 inch beyond the common plane (2) of the outer surfaces of the side and end

walls

30 and 40. with sheet packing of other thickness, the common plane y will extend beyond the common plane a: as required to suit the packing thickness, generally of the order of from 0.030 to 0.080 of an inch.

In any case the distance by which the common plane 1 extends beyond the common plane :2: will i be equal to the compressed thickness of the packing 42.

We claim:

1. A metal frame for a cooled slab mold havin side and end walls enclosing a recess with the outer surfaces of said walls machined to lie in a common plane and having integral longitudinal and transverse ribs dividing the recess into a plurality of longitudinal channels with communicating pockets, said machined outer surfaces of the side and end walls being adapted to have sheet packing compressed thereagainst, characterized in that the outer end surfaces of the longitudinal ribs are machined to lie in a common plane extending beyond said common plane of the outer surfaces of said side and end walls by a, distance equal to the thickness of .the compressed packing, and further characterized in that the transverse ribs adjacent each side wallhave over a part of their width immediately adjacent the side wall 2. A mold member for a cooled slab mold comprising a metal frame having side and end walls enclosing a recess with the outer surfaces of said walls lying in a common plane, the planar outer surfaces of said side and end walls being adapted to have sheet packing compressed thereagainst,

a plurality of longitudinal ribs dividing the recess.

into a plurality of longitudinal channels, a, series extended portions whose outer end surfaces are machined to lie in the common plane of the outer end surfaces of said longitudinal ribs.

of spaced transvers ribs forming communicating pockets in said channels, the outer end surfaces of said longitudinal ribs lying in a common plane extending beyond said common plane of the outer surfacesof said side and end walls by a distance equal to the thickness of the compressed packing, a mold face-plate covering the recess in said frame, a clamp bar secured to each side wall of said frame and firmly holding the face plate against the frame, the inner surface of said face plate andmost of the adjacent inner surfaces of said clamp bars lying in substantially the same plane as the outer suriaces of said longitudinal ribs while the remaining inner surface of each clamp bar lies in substantially the same plane as the outer surfaces of said side and end walls so that each clamp bar has an outside longitudinal rib in contact with the surface of the adjacent side wall, and a heat-resistant packing interposed between the outer surfaces of said side and end walls and the adjacent surfaces of the sides and ends of said face plate and clamp bars.

ERNEST c. FALK. ROBERT s. STORRS.

REFERENCES crriin The following references are of record in the file of this patent:

UNITED STATES PATENTS