US3058182A

US3058182A - Bottom ring assembly

Info

Publication number: US3058182A
Application number: US62757A
Authority: US
Inventors: Walter W Urmetz; Joel C Carpenter
Original assignee: Oglebay Norton Co
Current assignee: Oglebay Norton Co
Priority date: 1960-10-14
Filing date: 1960-10-14
Publication date: 1962-10-16
Anticipated expiration: 1979-10-16

Description

Oct. 16, 1962 w. w. URMETZ ETAI. 3,058,182

BOTTOM RING ASSEMBLY Filed oct. 14. 1960 s sheets-sheet 1 23 INVENTORS MIL r6@ M4 faMsrz By JOEL C .CARPENTER 14n-ORNE Ys OC- 16, 1962 w. w. URMETZ ETAL BOTTOM RING ASSEMBLY 5 sheets-sheet 2 Filed Oct. 14, 1960 NTORS WAL re@ 1M @METZ By ha C. CARPENTER Q f. Afro NEYS v 0d 16, 1952 w. W. URMETZ ETAL. 3,058,182

BOTTOM RING ASSEMBLY Filed Oct. 14. 1960 5 Sheets-Sheet 3 HIM X L INVENToRs WALTER Mnl/@Mrz f'/ S, BY JOEL C. CARPE/mm Arro EVS United States Patent Utilice 3,058,182 Patented Oct. 16, 1962 3,053,182 BSTOM RENS ASSEMBLY Walter W. Urinetz, Seven Hills, and loel C. Carpenter,

Chagrin Falls, Gino, assignors to Oglehay Norton Cornpany, Cleveland, Gliio, a corporation of Delaware Fiied Got. 14, 195o, Ser. No. 62,757 it) Claims. (Cl. 22-147) This invention relates to a bottom ring assembly for a hot top used with an ingot mold in the pouring of molten metal, such as steel, to produce an ingot.

More particularly the invention relates to a refractory bottom ring and wiper strip combined therewith and constituting a unit assembly.

This application is a continuation-in-part of Urmetz and Carpenter application ySerial No. 815,852, now abandoned, filed May 26, 1959.

As is well known in the art, hot tops are placed in the open upper ends of ingot molds and the molten metal is poured through the hot tops into the molds until they are filled and the hot tops contain a volume of the molten metal sufficient for the hot tops to function to feed the molten metal into the pipes or shrinkage cavities tending to form in the solidifying ingots.

A common form of reusable -floating type hot top comprises a refractory lined metal casing to the lower end of which a single use refractory bottom ring is attached by means of wire attaching clips.

The hot top usually is provided with a sheet metal wiper strip, the function of which is to form a seal between the hot top and the inner wall of the ingot mold to stop off the rising molten metal that enters the clearance space between the hot top and said wall. In other words, the function of the wiper strip is to seal off this clearance space to prevent the molten metal from rising too far therein or from overflowing the top edge of the mold. When the molten metal rises too far in this clearance space it is apt to form a fin around the hot top casing which would cause stickers when the hot top is being stripped from the sinkhead and the mold after the ingot has solidified. If the molten metal overilows the upper end of the mold and solidies it can produce hanger ingots causing hanger cracks on the surface thereof and interfering with the floating movement of the hot top relative to the ingot mold.

Wiper strips have been used in sets of a plurality of separate strips to a hot top and which strips conjointly extend completely around the lower end of the hot top casing. These wiper strips have an attaching portion that extends between the upper face of the bottom ring and the lower end of the casing of the hot top and are held in position by the bottom ring when it is secured to the casing by the attaching clips. The wiper strips have wiper lips which are integral with the attaching portions and project angularly and laterally upwardly of the periphery of the hot top.

To obtain correct positioning of the wiper strips relative to the ring and hot top casing the wiper strips in some instances have been provided with positioning tabs that iit into locating recesses formed in the bottom ring. Unless these positioning tabs and locating recesses are correctly interengaged the wiper strips may not be properly positioned so their wiper lips can have correct engagement with the mold wall. ln those instances wherein the casings of the hot tops are old and somewhat worn or distorted the bottom rings may not seat correctly against the lower ends of the hot top casings and this could cause the wiper strips to be improperly positioned so that their wiper lips lwill not make effective contact with the mold wall and provide the necessary seal between the hot top and the mold Wall.

The most generally used form of wiper strip is one secured in position by its attaching portion extending between the upper face of the bottom ring and the lower end of the hot top casing. Consequently the line of contact of the angularly and upwardly projecting wiper lip with the mold Wall is above the plane of the upper face of the bottom ring. This results in the molten metal having unrestricted freedom to `rise into the clearance space between the hot top and the inner wall of the mold until it contacts the wiper lip, and consequently increases the likelihood of the formation of fins about the lower yend of the hot top which might cause stickers Also reliance against the molten metal overflowing the mold depends on the functioning of the `wiper lip.

The most usual form of wiper strip does not protect the bottom ring against damage by engagement with the top of the mold when the hot top with the ring assembled thereon is lowered into the mold and is not properly aligned with the mold opening. This is particularly true when the hot top is inserted into a mold having a close fitting opening. Damage thus occurring to the refractory bottom ring may cause broken pieces or chips thereof to fall into the ingot mold and this may result in inclusions in the ingot unless such refractory pieces or chips are removed before the pouring of the molten metal.

In preparing a hot top for use the metal casing is mounted in inverted position on a preparation stand and the bottom ring is placed on the now uppermost lower end of the casing. 'Ihen the separate wiper strips are positioned by inserting the attaching portions thereof between the bottom ring and the lower end of the casing. Following this the conventional attaching clips are positioned and are connected to the vbottom ring and the casing to hold the bottom ring and wiper strips in position relative to the casing. This preparation procedure is time consuming. Also the bottom rings and the separate wiper strips prior to application to the casings of the hot tops must be separately shipped, stored and handled.

Efforts have been made to iind satisfactory methods of securing the wiper strips to the bottom rings during .the manufacture of the bottom rings. These efforts have included attempts to mold the wiper strips into the rings during the molding of the latter and this required special molding equipment for forming the rings and adds considerably to the cost of manufacture.

Efforts have been made to mechanically secure the wiper strips to the bottom rings and this would require that the rings be provided with cored holes, the formation of which complicates and slows down the ring molding operation. The mechanical attachment of the Wiper strips to the rings usually necessitates a costly operation such as riveting or the use of other mechanical securing means.

As above stated, a number of separate conventional wiper strips must be used each time the wiper strips are assembled with the hot top and the bottom ring and usually at least four wiper strips are required. This means that the separate wiper strip pieces must be handled separately from storage and each piece separately inserted and positioned between the hot top casing and the bottom ring during the preparation of the hot top for each pouring operation.

According to the present invention a vbottom ring assembly is contemplated that' includes a wiper strip means as part thereof and which eliminates the disadvantages of the conventional wiper strips and the manner of their securement to the hot tops and rings. In addition, the invention contemplates a bottom ring assembly of this character wherein the functioning of the wiper strip means to seal off the molten metal rising in the ingot mold is substantially increased in efficiency and the likelihood of stickers or of hanger ingots is minimized. In this latter connection the bottom ring assembly embodying the invention is so constituted that as the hot top moves in the ingot mold and the wiper lip of the wiper strip means engages the wall of the mold and is ilexed by such engagement the attaching portion of the wiper strip means at its junction to the wiper lip as a fulcrum will have a rolling action on the periphery of the bottom ring and will `cause the attaching portion at a location spaced axially downwardly from the wiper lip to move into the clearance space between the hot top and the -wall ofthe mold and thus substantially restrict this clearance space at a point closely adjacent to the lower entrance to such space. Therefore the molten metal is blocked or substantially blocked at the threshold of the clearance space from rising therein in a substantial volume thus lessening the production of fins or the likelihood of overllowing the mold whereby the danger of hot top stickers and hanger ingots is substantially reduced. This blocking of or reduction in the entrance to the clearance space supplements the sealing function of the wiper lip.

In the pouring of molten metal into ingot molds the pourer should momentarily shut olf the flow of metal when molten metal in the mold begins entering the clearance space between the hot top and the wall of the mold. This interruption is to allow the molten metal which has entered the clearance space to solidify sufficiently to seal off such space.

One of the purposes of the wiper strip is to produce a chill in the molten metal which has entered the clearance space and contacted the wiper strip to thus facili- 'tate the required degree of sealing solidi'cation of such molten metal.

In accordance with the present invention the chilling effect of the Wiper strip means on the molten metal at or in the clearance space is increased since both the wiper lip and the attaching portion of the wiper strip means which, due to the rolling action referred to has -rnoved into the clearance space, are effective for this purpose.

Also the present invention contemplates a wiper strip and bottom ring assembly which has manifold manufacturing and functioning advantages over those previously used or proposed, many of which will later be expressly pointed out.

According to the present invention assembly includes the use of an integrated wiper strip means for thc entire periphery and a portion of the lower face of the bottom ring, as distinguished from the use of -a plurality of separate wiper strip pieces inserted separately between the lower end of the hot top casing and the upper face of the ring during the preparation of the hot top. This wiper strip means can be assembled readily on and secured to the bottom ring in a simple assembling operation to constitute with the bottom ring a unitary assembly. This can be done in the plant of the manufacturer of the bottom rings and wiper strips and then the bottom ring assemblies can be handled, shipped, stored and applied to the hot tops as units with the resultant advantages incident thereto.

The assembly contemplated by the present invention provides a protection to the refractory bottom rings against the breaking or chipping of the edges or corners thereof during shipment and storage and during insertion of the hot tops into the molds. The unitary assembly of the bottom rings and wiper strip means has the advantages of conning and strengthening the bottom ring protectively by the embracing wiper strip means thereby eliminating the likelihood of reactory pieces or chips of the bottom rings falling into the molds when the ring and wiper strip assembly attached to the hot top is being lowered into the mold and unless the vchips are removed from the molds, they may cause serious inclusions in the metal ingots.

the bottom ring v The bottom ring and wiper strip unitary assembly of the present invention assures the correct positioning of the wiper strip means since the strip means is an integrated one and is attached to and backed up by the bottom ring and constitutes therewith a unitary assembly and hence is not subject to being disturbed from its proper position during the insertion of the hot top into the mold.

The bottom ring assembly embodying the invention possesses manufacturing, assembling and functional advantages in addition to those above referred to and many of which will be mentioned during the detailed description of embodiments of the invention which is to follow and which embodiments are illustrated in the accompanying drawings forming part of this specification and where- FIG. l is a sectional view through a reusable composite hot top of the floating type, to the lower end of the metal casing of which is attached a bottom ring assembly embodying the present invention, the hot top being illustrated as inserted into the open upper end of an ingot mold which is fragmentarily shown in section and prior to the wiper lip of the wiper strip means having contacted said mold.

FIG. 2 is a fragmentary view of the lower right hand portion of FIG. l but on a substantially enlarged scale as compared to FIG. l.

FIG. 3 is a view similar to iFIG. 2, but illustrates the relationship of the bottom ring assembly -with respect to the mold after the hot top has moved farther into the mold and the Wiper lip of the wiper strip means has engaged and been exed upwardly by the inner wall of the mold and the attaching portion of the wiper strip means, due to its rolling action on the periphery of the bottom ring, has moved outwardly thereof toward the inner wall of the mold to block or substantially block the entrance -to the clearance space bet-Ween the hot top and said inner Wall.

FIG. 4 is a plan view of the bottom ring assembly shown in `the previous views but detached from the casing of the hot top.

FIG. S is an elevational view of the bottom ring and wiper strip assembly of FIG. 4 but with said ring and strip separated and prior to being combined into the unitary assembly.

FIG. 6 is a sectional view taken substantially on line 6--6 of FIG. 3 looking in the direction of the arrows.

FIG. 7 is a fragmentary top plan view of va bottom ring and wiper strip assembly embodying the invention but in which the wiper strip means diiers specifically in structure from the wiper strip means shown in the first disclosed form of the invention.

FIG. 8 is a sectional view taken substantially on line 8 8 of FIG. 7 looking in the direction of the arrows.

FIG. 9 is a fragmentary sectional view of the embodiment shown in FIG. 7 and is similar to FIG. 3 but is taken in a slightly diierent vertical plane than is FIG. 3, namely, along line 9-9 of FIG. 7 looking in the direction of the arrows.

FIG. 10 is a plan View of yone complete element of Vthe wiper strip means and -of a portion of :an adjacent and like element of the wiper strip means of the embodiment of FIG. 7 and with said complete element and ysaid adjacent element being illustrated in separated relationship prior to being secured together.

FIG. ll is a side elevational view of the complete elcment of the wiper strip means shown in FIG. 10.

FIG. 12 is a plan view of a bottom ring and wiper strip assembly of a different form than those previously shown but embodying the present invention and wherein the bottom ring is formed of two substantially U-shaped sections with the wiper strip means unitarily Iassembled with each section and the sections constituting the two assemblies adapted to be separately applied and secured to the casing of a large size rectangular hot top, one section being shown in full lines and the other section in dash lines.

FIG. 13 is a fragmentary broken away top plan view on a large scale of the embodiment shown in FIG. 12 and illustrates two of the adjacent elements of the wiper strip means `of the assembly separated from the bottom ring section and from each other prior to being interconnected and united with the bottom ring U-shaped section.

FIG. 14 is a detail end elevational view of the wiper strip means shown in FIG, 13 and is taken looking at FIG. 13 substantially from line 14-14 thereof.

FIG. l5 is a plan View showing `an embodiment of the invention when used in connection with a round uted bottom ring formed of separate segments and with the wiper strip means of the combination integrated with each segment and having portions wrapped around the ends of the segments similarly as in the form shown in FIG. 12, one segment being shown in full lines and the others in dash lines, and

FIG. 16 is a view similar to FIG. 12 but illustrates the invention as embodied in a bottom ring formed of separate quarter sections, one of which is shown in full lines and the two 'adjacent sections in dash lines.

The hot top shown in FIG. 1 comprises the usual metal casing 16 which is illustrated as a two-part casing but it could be a one-part casing. The interior of the casing 16 is lined with refractory material which is illustrated in the form of irebrick 17 as lwill be understood in the art. A refractory bottom ring 18 is secured to the lower end of the hot top so as to underlie the hot top casing 16 and the brick lining 17 as will be understood in the art.

The hot top in use is positioned in the upper end of an ingot mold 19 and molten metal is poured into the mold to till the same and provide a quantity thereof in the hot top to form a sinkhead for a purpose well known in the art. The bottom ring 18 has Ian upper planar surface portion 18a which underlies the lower end of the casing 16 and an inner upstanding continuous rib portion 18h which extends upwardly within the lower end of the casing 16 and underlies the lower end of the refractory lining 17 as is well understood in the art. The bottom ring is secured to the hot top by means of substantially L-shaped wire attaching clips 20 which have a portion located beneath the bottom ring and provided at its inner end with an opstanding -leg portion 20a having a hook at its upper end which engages in a recess 18a` formed in the inner periphery `of the bottom ring as is well known in the art. The wire attaching clips 29 have a second upstanding leg portion 20h located outwardly -of the outer periphery of the bottom ring and casing land provided at its upper end with a hook that engages in a bushing 21 carried by the casing 16 all as is well known. The bottom ring 18 is secured to the casing 16 by a number of the attaching clips 20, at least four such clips being used depending on the size and shape of the hot top and spaced apart around the ring `and hot top.

The casing 16 and bottom ring 18 lare so dimensioned as to be positioned in the mold 19 with clearance space existing between the outer side of the casing 16 and bottom ring 18 and the wall of the mold. The width of this clearance space Will vary since ingot molds, ydue to manufacturing tolerances and other causes, may vary in `size resulting in tight or loose fitting molds relative to the hot top.

When molten metal is poured into the ingot mold the rise of this molten metal into the clearance space between the hot top and the mold wall is visually gauged as a rule by the pourer and an error could result in molten metal coursing up through the space and overflowing across the top of the mold.

In the pouring of the molten metal the pourer usually interrupts the pouring operation for a short time interval when he estimates that the molten metal is entering the clearance space. This is for the purpose of allowing the molten metal Whichhas entered the clearance space to solidify sufficiently to seal oif additional metal entering and rising in said space when the pouring operation is resumed.

As previously stated it has been customary to provide a seal in the form of wiper strips which have their attaching portions clamped in position between the lower end of the casing 16 and the upper surface 18a of the bottom ring 18 and which strips have integral wiper lips that extend angularly outwardly and upwardly from the periphery of the ring ,and contact the wall of the mold when the hot top is inserted therein and function to limit the upward ow of the molten metal in the clearance space between the hot top and the mold wall.

Heretofore it has been usual to employ a plurality of separate wiper strips, i.e., one for each of the four sides of a rectangular hot top, `and new strips must be positioned and used for each pouring operation and this means increased time in preparing the hot top and ring for each pouring operation.

The wiper lip of the wiper strip is dimensioned so it will tightly contact the inner Wall of the mold when the hot top is inserted in the mold and will be flexed upwardly 'by such contact since the wiper strip is usually formed of flexible sheet metal.

The wiper lip of the wiper strip in addition to providing a mechanical seal due to its contact with the mold wall also has a chilling effect on the molten metal in the clearance space that contacts the wiper lip and this facilitates the required solidication of such 4molten metal during the pause in the pouring operation.

The description heretofore set forth covers conventional matters. The bottom ring assembly according to the present invention will now be described. The Wiper strip means of the assembly may be a unitary structure and extend completely around the periphery of the bottom ring. The wiper strip means may be made as an integral stamping or it may be made of several stampings secured together to form the complete unit as, for instance, by weldin-g, riveting or otherwise suitably securing the several stampings together. The wiper strip means preferably is formed of sheet metal, although it could be formed of other suitable materials.

The wiper strip means of the embodiment shown in FIGS. l to 6 inclusive has 'an attaching and bottom ring engaging portion formed of a flange part 22 which extends beneath and contacts the lower face of the bottom ring 18 but is capable of sliding movement thereon. The flange part 22 is integral with and extends from the lower end of a vertically extending part 23 which, when applied to the bottom ring, contacts closely the outer periphery of the bottom ring as clearly indicated in FIG. 2.

The flange part 22 and vertical part 23 iit the lower outer edge of the ring with a fairly close fit and can be telescoped thereon. At the upper end of the vertical part 23 of the attaching and bottom ring engaging portion of the wiper strip means there is an integral outwardly and upwardly inclined or fflared wiper lip 24. The wiper strip means is applied to or telescoped on the bottom ring as a unit and is held in position on the bottom ring by its t thereon and by the engagement of upset knobs 25 formed in the vertical part 23 of the wiper strip means in indentations or recesses 26 formed in the outer periphery of the bottom ring, or by other cooperating means intertting each other and located on the ring periphery and the vertical part Z3.

The wiper strip means could be heated before application to the ring and then cooled to shrink into tight engagement with the ring, and in such event the mechanical interlitting means above referred to might be omitted.

The Wiper strip means and bottom ring 18 may be formed with any desirable number of cooperating knobs 25 and depressions or recesses 26 and for purposes of illustration two pairs of the cooperating knobs and depressions have been shown for each side of the wiper strip means and bottom ring, although the number could be lesser or ygreater as required and they can be located in any desired position. The hot top, bottom ring and wiper strip means have been illustrated as rectangular, but it will be understood they might be circular, square or otherwise shaped.

The wiper strip means can be assembled on the bottom rings to constitute units therewith by the manufacturer of the bottom rings and wiper strip means before shipment of the same to the ultimate user, that is the bottom rings with the strip means mounted thereon can be shipped as complete unit assemblies.

When the strip means are assembled on the bottom rings by the manufacturer prior to shipment and prior to use by the ultimate user, the 4wiper strip means serve to protect the lower outer edges of the bottom rings against chipping, cracking or other damage during shipment, storage and handling. Also it will be noted that the wiper strip means, due to tightly embracing the bottom rings, strengthen the latter in addition to protecting the same and function to retain any cracked portions of the rings in proper position with respect to the rings.

It will be noted that when the bottom ring assembly of the present invention is secured to the lower end of the hot .topl the attaching clips 20 extend beneath the flange part 22 of the attaching portion of the wiper stripy means and upwardly alongside but outwardly of the vertical part 23 thereof and through cutouts or slots 27 formed in :the wiper lip 24.

Also the vertical -part 23 and the ange part 22 of the wiper strip means at their `ang-le of interconnection are provided directly below the slots 27 with slots 2S, the

vertical portion of which extends a substantial distance upwardly of the vertical part 23 from the lower end thereof for a purpose later to be explained.

In order to increase the flexibility of the wiper lip, particularly at the corners thereof, said lip may be provided with slits 29, four of which are indicated in FIG. 4, but it will be understood that the number of slits 29 may be increased as is found desirable. Inasmuch as the wiper strip means is applied as a unit to the bottom ring, its correct positioning on the bottom ring is assured and it provides protection for the bottom ring including the outer lower edge and corners thereof.

Referring now to FIGS. 1 and 2 wherein the bottom -ring assembly is shown secured to the lower end of a hot top and the latter is starting its insertion movement linto the mold 19, it will be noted that the wiper lip 24 of the wiper strip means is of a length t overlie somewhat the upper end of the mold. The vertical part 23 of the wiper strip means acts to Ifacilitate, and guide the insertion of the hot top into the mold and with the flange part 22 thereof protects the refractory ring.

Now assuming that the hot top has moved into the mold 19 from the position shown in FIG. 2 to that shown in FIG. 3, it will be noted that the engagement of the wiper lip 24 `of the wiper strip means with the mold has flexed said wiper lip upwardly and that its free end is engaging the inner wall of the mold to provide a seal. Although the wiper lip 24 ilexes at the junction between its inner end and the upper end of the vertical part 23 of the wiper strip means, this angular junction has ia substantial measure of stiifness. Therefore the flexing of the vwiper lip 24 causes the angular junction between the lip .22 at this time present a block or a substantial block to the entrance of molten metal into the clearance space between the hot top and the inner wall of themold. In the case of a loose mold the vertical part 23 of the wiper strip means may move closely adjacent to but without contact with the inner Wall of the mold, while in the instance of a tight mold there may be contact.

As previously stated, the slots 28 in the vertical part 23 and flange part 22 of the wiper strip means and over which the attaching clips 20 lie provide clearance for the outward movement of these parts, it being recalled that the portion of the slots 28 in the vertical part 23 is of substantial vertical length while the portion of the slots in the ilange part 22 is shorter and extends horizontally. Also the ilange part 22 of the wiper strip means has outward sliding movement on the bottom face of the bottom ring when the vertical part 23 moves outwardly as described. It will also be noted during this rolling action and the outward movement of the

parts

23 and 22 that the knobs 25 in said part 23 can move outwardly relative to the recesses or depressions 26 in the bottom ring.

From the foregoing it will be seen that when the hot top is in 'operative position in the ingot mold the

parts

23 and 22 of the wiper strip means block or substantially block entrance to lthe clearance space between the hot top and the mold and hence restrict the flow of molten metal into such clearance space. However, the molten metal which may rind its way into the clearance space is of reduced volume and is adequately sealed against rising -too far in said space or overilowing the upper end of the mold by the wiper lip 24 of the wiper str-ip means.

It will be noted that the wiper strip means provides dual sealing `or restricting points against undesired rising of the molten metal in the clearance space between the hot top and mold `and spaced apart vertically of the hot top and thus efficiently protects against the danger of hot top stickers o-r hanger ingots.

Furthermore, the Wiper strip means of the bottom ring assembly of the present invention in addition to providing a more eiiicient mechanical seal itself, has the further advantage of facilitating the required degree of solidication of the molten metal adjacent to or in the clearance space between the hot top and the mold during the momentary pause 'in the pouring operation, since the parts 22 a-nd 23 of the wiper strip mean-s engaging such molten metal in addition to any engagement thereof by the wiper lip 24 increases the chilling eect of the vviper strip means on the molten metal.

It will be noted that should the hot top be misaligned with the mold opening during the lowering of the hot top into the mold, the wiper strip means of the assembly protects the refractory bottom ring against damage through inadvertent contact with the mold. In addition, the wiper strip means prevents chips, or broken pieces of fthe bottom ring from falling into the mold and unless removed `from the mold causing inclusions in the ingot.

Reference is now made to FIGS. 7 to 11 inclusive wherein is shown a bottom ring assembly embodying the invention but differing somewhat in structure from the bottom ring assembly previously described.

The hot top illustrated fragmentarily in FlG. 9 may be of the same construction as the hot top illustrated in FIGS. l to 3 inclusive and hence the portions of the hot top shown in FIG. 9 are identified Aby the same reference numerals as are `the corresponding portions of the hot top of FIGS. 1 to 3 inclusive. Insofar as the refractory bottom ring of the bottom ring and wiper strip means assembly shown in FIGS. 7 to l1 is identical with the previously described bottom ring the lsame reference numerals used to identify lthe different portions of the bottom ring.

The wiper strip means of the bottom ring assembly of FIGS. 7 to l1 inclusive comprises a plurality of separate identical elements which are secured together to provide a unitary wiper strip means that is applied and is secured as a unit to the bottom ring and surrounds the periphery rtw 9 of the bottom ring and extends beneath the lower face thereof.

-Each of the separate elements of the wiper strip means now being described has an attaching and bottom ring engaging portion formed of a vertical part which lies against the outer periphery of the bottom ring and an integral inwardly extending flanged part 31 which underlies and contacts the lower face of the bottom ring. The vertical part 3@ of each element is provided `at its upper edge with an integral outwardly and upwardly inclined or flared wiper lip 32. The vertical part 30l of each element is provided at its opposite curved ends with extended curved tabs 33 and 33a. When the elements of the wiper strip means are assembled together the tabs 33a of the elements will `overlie the tabs 33 of adjacent elements.

The tabs 33a of each element are provided with one or more lbutton-'lile nipples 34 which contact the tabs 33 of the adjacent elements. For purposes of illustration the button-like nipples 34 on the tabs 33a are shown as two in number and as being located adjacent the upper end of the part 30 and as being vertically spaced apart. The illustrated arrangement is a desirable one for a purpose later to be explained but it will be understood that the button-like nipples may vary in number and location from the illustrated showing thereof.

The elements of the wiper strip means are assembled together in a suitable jig or fixture so that the tabs 33a overlie the tabs 33 of adjacent elements while the curved opposite ends 32a of the wiper lip 32 of each element overlie in one instance and underlie in the other instance the curved opposite ends 32a of the wiper lip 32 of adjacent elements as clearly shown `in FIG. 7 and can have movement relative to each other when the strip means tlexes. The opposite ends of the flange parts 31 of the elements are beveled to intert with the en'ds of the flange parts 31 of adjacent elements. The overlapping tabs 33a and 33 are then secured together preferably by electric welding at the location of the nipples 34, although they could be secured together by other suitable means as, for instance, by riveting. When the tabs 33a and 33 are secured together as by electric welding as indicated in FIG. 8, the nipples 34 of the tabs 33a are fused into the metal of the overlying tabs 33a and 33.

It will be seen that when the tabs 33 and 33a are secured together the separate elements of the wiper strip means are then united into a single unit which can be applied and secured as such to the bottom ring of the bottom ring assembly. If the bottom ring is of rectangular configuration for use on the lower end of a rectangular hot top, then the secured together tabs 33 and 33a are located at the corners of the wiper strip means unit and of the bottom ring. The Wiper strip means unit will tightly t and surround the periphery of the bottom ring as in the previously described form and the ange parts 31 will underlie Vand contact the lower face of the bottom ring but will be capable of movement thereon. When the wiper strip means is positioned on the bottom ring then by means of a suitable upsetting operation the secured together tabs 33 and 33a are deformed or pressed inwardly to provide portions 35 that ex-tend into receases 36 formed in the periphery of the bottom ring and which recesses, if the bottom ring ds rectangular, will be at the corners thereof or at some other suitable location.

The wiper lips 32 of the wiper strip means are provided with slots 37 through which the portions 29h of the attaching clips 30 can extend. Also the vertical part 30 and the flange part 31 of the wiper strip means are provided at their junction with cutouts or slots 38 vertically aligned with the slots 37 and similar in purpose to the slots or cutouts 28 of the form of the invention described with reference to FIGS. l through 6 inclusive; it being noted that the portion of the slots 38 in the vertical par-t 30 of the wiper strip means extend a substantia-l distance upwardly of said part from the lower edge thereof and are longer than the portions of the slots 3S that are in the flange parts 31. In addition, the wiper lips 32 may be provided with slits 39 to further increase tne flexibility of the wiper lips. Although these slits 39 are illustrated as being -two in number for each section and as located adjacent the curved opposite ends 32a Iof the wiper lip sections so as to position said slits 39 adjacent to the corners of the bottom ring assembly, it will -be understood that additional slits corresponding to the slits 39 'can be provided in the wiper lips 32 if desired and at other locations.

It was previously stated that the curved opposite ends 32a of the wiper lips of the sections have overlapping relationship land since these curved ends are not interlocked against relative movement, the flexibility of the wiper lips at the curved ends is not .restricted yand is relatively free, particularly in -view of the slits 39. Also since the loverlap-ping tabs 33 and 33a of the vertical parts 3l? of the wiper strip means are secured together preferably adjacent to the upper edge of said parts 30 the wiper strip unit at the corners thereof will have the required measure of freedom or adaptability so that under the rolling action later to be referred -to of the junction between said vertical parts 30 and wiper lips 32, said parts 30 can move outwardly into the oleanance space -between the bottom .ring and the mold. Also during such movement the flange parts 3l can move outw-ardly along the bottom face of the bottom ring as in the previously described form.

It will be understood that when a hot top with the bottom ring and wiper strip assembly of the construction shown in FIGS. 7 through 1l secured to the lower end of its casing is inserted into a mold and the wiper lips 32 thereof contact the mold, said lips 32 will be llexed upwardly and at the same time a rolling action against the periphery ofthe bottom ring will yoccur on the fulcrum at the junction between the wiper lips 32 and the upper edge of the vertical parts 3G and cause said vertical parts and also said flange parts 31 to move outwardly with respect to the bottom ring to block or substantially block the entrance to the clearance space between the hot top and lthe mold for the same purpose :and with the same advantages as have been pointed out with reference to the description of the embodiment of the invention shown in FIGS. 1 through 6.

'In FIGS. l2, 13 and 14 a further embodiment of the invention is illustrated. In the case of large size hot tops as, for instance, large size rectangular hot tops, it has been customary to have the bottom rings formed of separate section-s as, Ifor instance, two substantially U-sha-pe-d sections, which are secured to the lower end of the casing of the hot top and combined extend cornpletely around said lower end of the casing. This type of arrangement is shown in FIG. l2 wherein one of the substantially U-shaped bottom ring sections is indicated at 40 in `full lines `and the other substantially U-shaped section 40 is yfragmentarily shown in dash lines.

Each bottom ring section 40 is provided with the raised rib 18b on its upper side and with the att-aching clip recesses 18e as in the previously described bottom rings. The `outer periphery of the bottom ring sections 46 is illustrated as provided with curves or waves.

Each bottom ring section 40 has assembled and in- Itegrated therewith three sections of a wiper strip means, with the two sections of said means that are on opposite sides of the bottom ring being identical in construction, while the end section of said wiper strip means differs somewhat in structure from the other two as will soon bcome apparent.

All of the sections of the wiper strip means have an attaching and bottom ring engaging portion comprising a flange part 41 which extends beneath and contacts the lower face of the bottom ring section :and a vertical part 42 integral with the flange part and extending vertically of the periphery of the bottom ring section as will be understood from the description of the previously described forms of con-struction. The upper edge of the vertical part 42 has the integral outwardly flared wiper lip 43 extending therefrom. The vertical par-t 42 and the wiper lip 43 are provided with waves or curves corresponding to the contour of the periphery of the bottom ring section.

In order to provide suicient flexability in the wiper lip 43, particularly in view of its wavy configuration, said lip is provided with a plurality of spaced slits 44. Also the wiper llip 43 is provided with cutouts 45 through which Ithe attaching clips (not shown in FIGS. 12 and 13) can extend as will -be well understood.

In vertical alignment with the cutouts 45 the flange part 41 and vertical part 42 of the wiper strip means are provided with slots 46 with .the longer portion of the slots 46 being in the vertical part 42 las Was the case of the

slots

28 and 38 in the previously described forms. It will be understood that the purpose of the slots 46 is the same as lthe previously referred to

slots

28 and 38.

The section of the wiper strip means for the closed end of the substantially U-shaped bottom ring section 40 is provided at its opposite ends fand on the vertical part 42 thereof with projecting tabs 47. The vertical parts 42 of the side sections of the wiper strip means 'are provided .at the ends of said sections which are adjacent yto the opposite ends of the end section of the wiper strip means with projecting tabs 4S. When the Wiper strip means sections are assembled together the

tabs

47 and 48 overlap and are secured together by suitable means as, for instance, one or more welds similarly to the tabs 33 .and 33a of the embodiment shown in FIGS. 7 to 11 inclusive.

rFhe opposite curved ends 43a of the wiper lip 43 of the end section of the wiper strip means slidably overlap the adjacent curved ends 43b of the wiper lip 43 of the side sections of the wiper strip means. When the united end and side sections of the wiper strip means are assembled with athe U-shaped bottom ring section 40 the flange parts 41 of the wiper strip means sections underlie and contact the bottom face of the lbottom ring section while the vertical parts 42 of the wiper strip sections follow the contour of and contact the periphery of the 4bottom ring section 4t). The overlapped and secured together

tabs

47 and 48 overlie the end corners 49 of Athe bottom ring section 4t). The bottom rin-g section 40 on opposite sides of the corners 49 thereof is provided with recesses 50 and 4the vertical parts 42 of the side and end sections of the wiper strip means are crimped or deformed to have portions 50a extending into the recesses 50.

In order to secure the free ends of the side sections 1of the wiper strip means to the free ends of the U-shaped bottom ring sections 40 said side sections can be said to -be wrapped around the free ends of the bottom ring sections. The arrangement for doing this will now be described.

The yfree ends of the bottom ring sections 46 .are provided in their upper surfaces with recesses 51 that extend from Vthe periphery of the bottom ring transversely toward the rib 1gb thereof and which recesses have a horizontal supporting or engaging sur-face. The free ends 'of the bottom ring sections also are provided iat the inner ends of the recesses 51 and communicating therewith with vertical recesses 52. l

The vertical parts 42 -a-t the free ends of the side sections of the wiper strip means are extended and turned at right angles to provide integral portions 42a which bear against the vertical free end surfaces of the bottom ring section 40. The por-tions 42a on their upper edge have integral horizontal tabs 42h which fit into the recesses 51 in the bottom ring section and bear on the horizontal `supporting surfaces thereof. The portions 42a at vtheir fre-e ends have integral vertical tabs 42a` whi-ch loosely extend into the vertical recesses 52 in the 'free ends of the bottom lring'section but allow the

parts

42 and 41 to move when the part 42 is rocked. The portions 42a on their lower edge have an integral flange 42d which extends horizontally beneath the flange part 41 of the wiper `strip means. The flange 42d is oiset Ito intert the flange part 41, but beyond the offset the flange 42d contacts the underside of the bottom ring section 40. The iiange 42d may tbe secured to the flange part 41 of the wiper strip means by spot Welding the same thereto as indicated in FIG. 13 or by any other suitable securing means.

It will be understood that each bottom ring section 40 has assembled therewith a wiper strip means formed of the two side sections and the end section in a manner previously described. Also it Will be understood that the assembled bottom ring and Wiper strip section is secured by the attaching clips to the lower end of the hot top casing and the free ends of said assembled bottom ring and wiper strip section abut the free ends of an identical section that is similarly secured to the hot top to form a complete bottom ring and wiper strip assembly on the lower end of the hot top. This is indicated in FIG. 12 by the one bottom ring and wiper strip assembly section shown in full lines and the other such section shown in dash lines.

It will further be understood that the bottom ring and wiper strip assembly of the form shown in FIGS. 12 through 14 and embodying the invention when secured to a hot top cooperatively with another such assembly and the hot top is inserted into an ingot mold, the wiper lips 43 will engage the mold and a rolling action against the periphery of the bottom ring sections will occur to cause t-he vertical part 42 and the iiange part 41 of the wiper strip means to move outwardly and block or substantially block the entrance to the clearance space between the hot top and the mold just as in the previously described forms, it being recalled that the loose engagement of the tab 42e` in the vertical recess 52 permits this movement.

Inasmuch as the wiper lips are provided with slits 44 and the cutouts 45, the wiper lips will have flexibility, particularly if the slits 44 are located so as to interrupt the continuity of the curves in the wiper lips. Also since the overlapping curved ends of the wiper lips of the side sections and those of the end section are free to have limited relative movement, the exibility of the wiper lines.

`In FIG. 15 the upper surface of the bottom ring segments is indicated at 53 and each segment is provided with a substantially arcuate upwardly extending rib 181; and has the recesses 18e for the hooks on the inner ends of the attaching clips not shown. The wiper strip means that is assembled and integrated with each ybottom ring segment has an attaching and bottom ring engaging portion formed of a flange part 54 contacting the under surface of the bottom ring segment and a vertical part 55 that is convoluted to conform to and engages the periphery of the bottom ring segment just as in the previously described forms.

The upper edge of the vertical part 55 of the wiper strip means is provided with the integral flared 4wiper lip 56. The wiper lip 56 has the slots S7 for the attaching clips and said slots 57 are shown as located in the crest of the convolutions of the wiper lip 56. Also the curves of the wiper lip 56 are interrupted by one or more slits 58 which with the slots S7 provide the requisite exibility for the Wiper lip.

The opposite ends of the wiper strip means for each segmental bottom ring section are wrapped around and are secured to the opposite ends of said bottom ring segment in the same manner as are the free ends of the wiper strip means with respect to the free ends of the bottom ring sections in the form shown in FIGS. 12 through 14.

Each bottom ring segment 53 on its periphery is provided with a suitably located recess or recesses 59 and the vertical part 55 of the wiper strip means is crimped or upset into said recesses 59 as indicated at 60. It will be understood that the bottom ring segments each have assembled therewith the wiper strip means and these assemblies are separately attached to the lower end of the hot top casing so as to extend completely therearound with the ends of each assembly abutting the ends of adjacent assemblies. It will also be understood that the flange part 54 and vertical part 55 of the wiper strip means are provided with L-shaped slots 61 similar to the previously described

slots

28, 3S and 46 and for the same purpose.

It will further be understood that when a hot top having secured thereto the circular bottom ring shown in FIG. 15 is inserted into a mold and the wiper lip 56 is eXed by its engagement with the mold wall, the rolling action of the junction between the wiper lip 56 and the vertical part 55 takes place against the periphery of the refractory bottom ring and causes said vertical part 55 and flange part 54 to move outwardly toward the wall of the mold to block or substantially block the entrance to the clearance space between the hot top and the mold.

In FIG. 16 a further embodiment of the invention is illustrated. Here there is shown a portion of a large size rectangular bottom ring made up of quarter sections, one of which is shown in full lines while the two adjacent ones are fragmentarily indicated in dash lines. Each bottom ring section is substantially L-shaped and the upper surface thereof is indicated at 62. Each bottom ring section has the raised rib 18h and the recesses 18C for the attaching clips as in the previously described forms.

Each bottom ring quarter section has assembled thereon a quarter or substantially L-shaped wiper strip means section. Each wiper strip means section has an attaching and bottom ring engaging portion including a ange part 63 that contacts the underface of the bottom ring section and a vertical part 64 that engages the periphery of the bottom ring section. The vertical part 64 has integral with its upper edge the ared wiper lip 65. This wiper lip 65 is sloted as at 66 for the attaching clips and has a number of spaced slits 67 therein to provide eXibility for the wiper lip, one of said slits being at the corner of the wiper strip means section as illustrated in FIG. 16.

The opposite ends of each wiper strip means section are wrapped around and secured to the opposite ends of each bottom ring quarter section in the same manner as are the ends of the wiper strip means sections in the forms shown in FIGS. 12 through 15. Each bottom ring quarter section in each arm or leg thereof is provided on its periphery with one or more recesses 68 into which the vertical part 64 of the wiper strip means is crimped or upset as indicated at 69.

The embodiment of the invention shown in FIG. 16 functions in the same way and with the same advantages as do the previously described embodiments.

Although a number of different embodiments of the invention have been illustrated and described herein, it will be understood that the invention is susceptible of various modications and adaptations within the Scope of the appended claims.

Having described our invention we claim:

1. A bottom ring and wiper strip unit assembly for a floating composite type hot top for an ingot mold and comprising a refractory bottom ring adapted to be secured to the hot top metal casing by attaching clips, and sheet material wiper strip means mounted on and united with said bottom ring as a unit assembly therewith and including an attaching portion having a horizontal flange slidably contacting the lower face of the bottom ring and a vertical part integral with said llange and tiltably engaging the outer periphery of the bottom ring and from the upper edge of which extends angularly outwardly and upwardly an integral wiper lip adapted to be ilexed upyWardly by engagement with the mold wall, said flange vand said vertical part being provided With interconnecting openings located to be in the vertical plane that includes the attaching clips which secure the unit assembly to the hot top casing, whereby when the unit assembly is attached to a hot top and the latter is inserted in an ingot mold and the wiper lip is flexed upwardly said vertical part tilts on the ring periphery at the junction of said wiper lip and said part to cause said ange to slide on the lower face of said ring into the clearance space between the hot top and the mold wall at a location spaced inwardly of the mold from wiper lip engagement with said wall.

Z. A bottom ring and wiper strip unit assembly for a lloating composite hot top for an ingot mold as dened in claim l and wherein Said wiper lip is provided with attaching clip slots and the said openings in the vertical part of said Wiper strip means are elongated upwardly toward said wiper lip whereby when the unit assembly is attached to a hot top and the latter is inserted in an ingot mold and the wiper lip is flexed upwardly said vertical part tilts through a substantial angle on the ring periphery at the junction of said wiper lip and said part notwithstanding the presence of attaching clips to cause said ange to slide on the lower face of said ring a substantial distance into the clearance space between the hot top and the mold wall at a location spaced inwardly of the mold from wiper lip engagement with said wall.

3. A bottom ring and wiper strip unit `assembly for a lloating composite type hot top for an ingot mold and comprising a refractory bottom ring adapted to be secured to the hot top metal casing `by attaching clips, and sheet material wiper strip means mounted on and united with said bottom ring as a unit assembly therewith and formed of a plurality of separate sections conjointly embracing the periphery of the ring, each section including an attaching portion having a horizontal flange slidably contacting the lower face of the bottom ring and a vertical part integral with said flange and tiltably engaging the outer periphery of the bottom ring and from the upper edge of which extends angularly outwardly and upwardly an integral wiper lip adapted to be llexed upwardly by engagement with the mold wall, said llange and said vertical part of each section being provided with interconnecting openings located to be in the vertical plane that includes the attaching clips which secure the unit assembly to the hot top casing, whereby when the unit assembly is attached to a hot top and the latter is inserted in an ingot mold and the wiper lips of the sections are flexed upwardly said vertical parts tilt on the ring periphery at the junction of said wiper lips and said parts to cause said anges to slide on the lower face of said ring into the clearance space between the hot top and the mold wall at a location spaced inwardly of the mold froml wiper lip engagement with said wall.

4. A bottom ring and wiper strip unit assembly for a floating composite type hot top for an ingot mold and comprising a refractory bottom ring adapted to -be secured to the hot top metal casing by attaching clips, and sheet material wiper strip means mounted on and united with said bottom ring as a unit assembly therewith and including an attaching portion having a horizontal flange slidably contacting the lower face of the bottom ring and a vertical part integral with said ange and tiltably engaging the outer periphery of the bottom ring and from the upper edge of which extends angularly outwardly and upwardly an integral wiper lip adapted to be flexed upwardly by engagement with the mold wall whereby when the unit assembly is attached to a hot top and the latter is inserted in an ingot mold and the wiper lip is llexed upwardly said vertical part tilts on the ring periphery at the junction of said wiper lip and said part to cause said -ilange to slide on the lower face of said ring into the clearance space between the hot top and the mold wall at a location spaced inwardly of the mold from wiper lip engagement with said wall.

5. A bottom ring and wiper strip unit assembly for a oating composite type hot top for an ingot mold and comprising a refractory bottom ring adapted to be secured to the hot top metal casing by attaching clips, and sheet material wiper strip means mounted on and united with said Abottom ring as a unit assembly therewith including an attaching portion having a horizontal flange slidably contacting the lower face of the bottom ring and a vertical part integral with said ange and tiltably engag- Iing the outer periphery of the bottom ring and from the upper edge of which extends angularly outwardly and upwardly an integral wiper lip adapted to be iiexed upwardly by engagement with the mold wall, said ring being provided on its periphery with recesses and said vertical part 'being provided with projections movably extending into said recesses, said ange and said vertical part being provided with interconnecting openings located to be in the vertical plane that includes the attaching clips which secure the unit assembly to the hot top casing, whereby when the unit assembly is attached to a hot top and the latter is inserted in an ingot mold and the wiper lip is ilexed upwardly said Vertical part tilts on the ring periphery at the junction of said wiper lip and said part to cause said flange to slide on the lower face of said ring into the clearance space between the hot top and the mold wall at a location spaced inwardly of the mold from wiper lip engagement with said wall.

6. A bottom ring and wiper strip unit assembly for a floating composite type hot top for an ingot mold as defined in claim 5 and wherein said sheet material wiper strip means is an integral stamping intertting and extending around the outer periphery of the ring and engaging the lower face of said ring.

7. A rbottom ring and wiper strip unit assembly for a floating composite type hot top for 'an ingot mold as de- Vstrip means are elongated upwardly toward said wiper lip, Vwhereby when the unit assembly is attached to a Vhot top and the latter is inserted in an ingot mold and the wiper lip is llexed upwardly said vertical part tilts through a substantial angle on the ring periphery at the junction of said wiper lip and said part and due to the lever length of said part causes said flange to slide on the lower face of said ring a substantial distance into the clearance space between the hot top and the mold wall at a location spaced inwardly of the mold from wiper lip engagement with said wall. Y

8. A bottom ring and wiper strip unit assembly for a floating composite type hot top for an ingot mold as delined in claim 5 and wherein said sheet material wiper strip means is formed of a plurality of separate sections conjointly embracing the pheriphery of the ring, each section including said horizontal ilange, said vertical part and Said Wiper lip; the vertical parts of said sections having end portions arranged in overlapping relationship and secured to similar end portions of the vertical parts of adjacent sections, the projections of said Vertical parts which extend into the said recesses in the periphery of the ring being formed in the overlapping end portions of said parts.

9. A bottom ring and wiper strip unit assembly for a iloating composite type hot top for an ingot mold as dened in claim 8 wherein said wiper lips are provided with attaching clip slots and said vertical parts extend upwardly to close proximity to the upper face of the ring and the openings in said vertical parts are elongated upwardly from the interconnecting openings in said flanges toward said wiper lips, whereby when the unit assembly is attached to a hot top and the latter is inserted in an ingot mold and the wiper lips are flexed upwardly said vertical parts tilt through a substantial angle on the ring periphery at the junction of said wiper lips and said parts and due to the lever length of said parts cause said lianges to slide on the lower face of said ring a substantial distance into the clearance space between the hot top and the mold wall at a location spaced inwardly of the mold from wiper lip engagement with said wall.

l0. A bottom ring and wiper strip unit assembly for a oating composite type hot top for an ingot mold and comprising a refractory bottom ring adapted to be secured to the hot top metal casing by attaching clips, said bottom ring being formed of a plurality of separate sections shaped to conjointly intert the lower end ofthe hot top, and sheet material wiper strip means mounted on each ring section as a unit assembly therewith and including an attaching portion having a horizontal ange slidably contacting the lower face of the ring section and a vertical part integral with said ilange and tiltably engaging the outer periphery of the ring section and from the upper edge of which extends angularly, outwardly and upwardly an integral wiper lip adapted to be flexed upwardly by engagement with the mold wall and provided with attaching clip slots, each of said ring sections and said Vertical parts of the wiper strip means having interengaging but relatively movable portions maintaining the wiper strip means assembled on the ring sections to be attached as a unit therewith to the hot top but with said vertical parts tree to have tilting movement on the ring sections about the fulcrum at the junction between the upper edge of said Yvertical parts and the wiper lips, said ilanges and said vertical parts being provided with interconnecting openings in the vertical plane that includes said slots whereby when the assembly is attached to a hot top and the latter is inserted in an ingot mold and the wiper lips are flexed upwardly said vertical parts tilt on the ring periphery to cause said anges to slide on the lower faces of said ring sections into the clearance space between the hot top and the mold wall at a location spaced inwardly of the mold from the wiper lip engagement with said wall.

References Cited in the tile of this patent UNITED STATES PATENTS 2,258,483 Charman Oct. 7, 1941 2,300,077 Urmetz Oct. 2.7, 1942 2,426.748 Rees et al. v .r Sept. 2, 1947