US3540713A - Steel making ladle construction - Google Patents

Description

United States Patent [72] Inventor Harry T. Montgomery New Castle, Pennsylvania [2!] Appl. No. 801,256 [22] Filed Feb. 24, 1969 [45] Patented Nov. 17, 1970 [73] Assignee Pennsylvania Engineering Corporation New Castle, Pennsylvania a corporation of Pennsylvania [54] STEEL MAKING LADLE CONSTRUCTION 13 Claims, 7 Drawing Figs. [52] U.S. Cl 266/39, 13/33; 263/48; 266/43' [51] Int. Cl F27d 15/00 [50] Field of Search 263/48, inquired 266/34, 37, 38, 39, 43; 13/33, 35 [5 6] References Cited UNITED STATES PATENTS 1,861,946 6/1932 Wilhelmi 266/39 3,006,046 10/1961 Shephard et al.... 266/43 3,162,710 12/1964 Anderson 266/39 3,350,085 10/1967 Over Primary Examiner-Gerald A. Dost Attorney-Green, McCallister and Miller ABSTRACT: A large capacity ladle for processing molten ferrous metal is provided having a metal outer shell-like body of oval, cylindrical or lengthwise-straight barrel shape, a closed bottom portion of dished or flat shape, and a replaceable inner lining of refractory brick or tile members defining a frustoconical molten metal receiving cavity that converges towards the closed bottom portion thereof. A permanent type of intermediate lining is applied to and is adherently set along the inner side of the metal shell wall to provide it with a frustoconically contoured back-up support for the innermost refractory brick or tile lining; the intermediate lining is adapted to withstand the high temperatures and variations in temperature of the utilization, and to provide an inner mounting wall for supporting the conventional refractory brick or tile that is replaceable with respect thereto for servicing of the ladle.

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aiemw Nov. 17, 1976 INVENTOR. H rry 7. Manfgamery Zw, 7L .553. p

HIS ATTORNEYS STEEL MAKING LADLE CONSTRUCTION This invention relates to a new and improved type of molten metal handling or processing ladle vessel and particularly, to a ladle having a straight side, fully cylindrical or oval barrel construction. 1

Previous to the present invention those skilled in the art thought it to be necessary to design, construct and use metal processing ladles of a so-called tapered or frustoconical metal wall or barrel construction wherein the sides thereof have a vertical-downward declining body slope from its open upper end or mouth portion towards its closed lower end. In other words, longitudinal or vertical tapering has heretofore been considered as necessary in the construction of apractical form of ladle and particularly, of a so-called vertical ladle utilizing centrally-positioned, outwardly-projecting side trunnions.

There has been aneed, however, for an improved form of ladle and, as a'result, a thorough evaluation of various factors entering into the utilization of a ferrous molten metal processing ladle has been accomplished which has led to rather startling discoveries and a solution to difficulties which rise to difficulties which were not appreciated, and that a straight sided barrel shape would resultin an improved, more economical and practical construction and utilization.

Heretofore, it has been the practice of those skilled in the art to provide a ladle having a frustconical shape of metal shell wall with a refractory lining following the slopeof such wall along its inner side. The present'invention deals with the I elimination of such a type of shell wall toprovide one of fully cylindrical or oval shape, and to do so in such a manner as to simplify making the metal parts of the construction and to.

decrease the overall cost of the construction. Heretofore, it

, has been customary to fill in any space'or unevenness in a brick or tile lining with respect to it and the metal shell wall 'with loose material and so-called mud" or brick setting clay which, of course, has to be replaced when brick of the lining is replaced.

In order to eliminate the need for an inwardly-converging or sloped metal shell wall and a tapered construction for trunnion mounting parts,etc and at the same time, to provide the necessary slope of the cavity or inside of the ladle for the purpose of removing solidified metal therefrom, l have devised a permanent type of. intermediate filler wall construction which provides the necessary downward frustoconical convergency of the refractories and,at the sametime, fully and effectively supports them within a cylindrical shell Wall and along its extent. In this connection, a refractory monolith, a castable ramming mix or plastic containingmaterial that can'be mixed and blown in place or applied by a trowel in the same manner as concrete, is applied to the inner side of the shell wall in such a manner as to provide the desired frustoconical shape. It is permitted toset and form a permanent part of the inner wall of the ladle before the refractory'brick or tile constituting the lining is mounted in position. The material not only protects the metal shell wall, but'has a life substantially corresponding to that of the shell wall. The assignee has a-suita-ble permanent lining material bearing the trademark Posi-Fil"; also, Harbison-Walker has a material designated'as light weight, '80 pounds extra strength; castable 4064"; A. P. Green Refractories Co. has a trademarked material Kastolite"; and General Refractories Co. has a-similar-material. The material should have a use limit of not less than abut2,500F. It may be applied at room temperature by a nozzle and setswith insignificant shrinkage and can be cured by air drying. It has been found to be compatiblewith metal such as the shell wall.

The refractorymaterial is easily mixed and poured to provide a bonded thickness or area from a relatively thinner, upper, starting thickness portion to a relatively thicker bottom thickness which not only securely anchors to the inside of the metal shell, but which will withstand relatively high heat, such as results from handling molten steel having a temperature in the neighborhood'of around 2,700F. or 3,000F. Of course, the refractory lining reduces the temperature considerably during direct heat transfer from the molten metal to the outer shell wall. The ingot heat to which the bottom portion of the ladle is subjected from molds into which the metal is being poured has been found to be suitably dissipated without damaging the metal shell wall or the intermediate lining. Also, the lining has a resiliency or flexibility such that it will expand and contract with the metal shell without losing its securely bonded relation therealong.

It has been determined that there are three important factors which have to be met in order to provide a practical, effcient and economical straight-sided ladle construction, namely, the use ofa monolithic contouring material that will have a permanently anchored set along an inner side of the metalshell wall so as to, in effect, form an integral part thereof; that will have a coefficient of expansion and contraction compatible with that of the metal shell wall or will have sufficient resiliency to be compatible therewith; that will have the capability of less heat transference than that of the refractory lining and-than that of the metal shell wall; that will retain its full strength at normal operating heats of the ladle and under the expansion and contraction and variations of temperature encountered in its use; and finally, that will retain a securely anchored relation when brick or tilemembers of the refractory lining are being replaced from time to time. Another important factor is that the monolithic reference lining, itself, should provide the necessary or desired'slope or taper downwardlyinwardly towards the bottom portion of the ladle. The

'monolithic 'mater ial should'be capable of withstanding the changes in temperature without weakening under service conditions. The above-mentioned commercial products have been found to meet these requirements and to serve satisfactorily in this connection.

Finally, a great cost reduction was encountered from the standpoint of the construction and mounting ofplate members of the metal shell, and of other metal parts. An operational advantage has been obtained from the standpoint of an increased bail or stand clearance from the central transverse trunnion axis to the edge of the nose ring of open mouth portion of the ladle. Tilting of the ladle was found to be facilitated from the standpoint of equal clearance along its outer reaches and from the standpoint of better balancing of it due to the fact that its side walls along their full length are of uniform dimension.

In accordance withthe invention, a fully oval or cylindrical metal shell wall or barrel is provided which is relatively less expensive to manufacture and shape than a frustoconical type and whose trunnion band, supporting rings and supporting shelf parts may beall less expensively made by reason oftheir inner cylindrical, as distinguished from an inner tapered periphery. More supporting bail clearance and operative stability are assured. For simplicity of illustration, a teeming type of ladle has been shown'in the drawings, although a pouring type can be provided by adding a spout which may be angled outwardly from or parallel with the straight outer side thereof.

In view of the above considerations it has been an object of the invention to devise a solution to the problem of providing pensive in constructionand which provides an efficient type of ladle processing operation;

A still further object of the invention has been to develop an improved ferrous metal processing ladle which will make possible material savings in time and cost of its construction and will enable molten metal to be handled efficiently in a steel or ferrous metal melting and refining operation;

These and other objects of the invention will appear to those skilled in the art from the illustrated embodiment and the claims. i

In the drawings:

Fig. l is a somewhat diagrammatic vertical section in elevation illustrating certain factors entering into the invention herein involved; in this FIG. the dotted lines represent the inner shape of a conventional priorart tapered, conical or sloped side ladle construction and the full lines represent the shape ofthe metal wall body ot'a ladle ofthe invention;

FIG. 2 is an enlarged side view in elevation and partial section of the preferred ladle constructed in accordance with the invention, taken in the direction ol'thc axis of trunnion pins or shafts ofthe ladle;

FIG. 3 is a horizontal section on the scale of and taken along the line Ill-Ill of FIG. 2;

FIG. 4 is a fragmental section in elevation on a reduced scale with respect-to FIG 2, illustrating a modified embodiment of the invention;

FIG. 5 is a fragmental section in elevation on the scale of FIG. 4 illustrating another embodiment ofthe invention;

FIG. 6 is a fragmental section in elevation on the scale of FIGS. 4 and 5 showing another embodiment of the invention;

and t FIG. 6A is a greatly enlarged fragment showing details of the construction of metal clips or anchors.

In accordance with a phase of the present invention, a ladle vessel 10 has been devised having a straight-sided, elongated, main metal side wall body'or shell 11 which, at its upper end, terminates in an open mouth top portion 11a and at its lower end in a closing-off bottom portion llb The main shell wall I I has substantially the same section along its full length or extent and is of generallyelongated oval or cylindrical shape.

FIG. I is somewhat diagrammatic and shows the sloped or downwardly-declining metal side wall body construction of a conventional ladle vessel 9 by dotted lines, and the straight side construction of the metal body of a ladle l0'constructed in accordance with the invention.

Referring particularly to FIGS. 2 and 3 of the drawings, 1' have for the purpose of illustration, shown a te eming type of vessel 10.It will, however, be appreciated that the invention may be applied to other types, such as a pouring type with spout added. A teeming type, of course, will normally have a bottom pouring noz'zle or orifice 16, an associated control plug or stopper, and an adjustment and mounting assembly for the plug. The latter havebeen omitted for simplicity of illustration. It will be appreciated that the straight barrel shape of the vessel 10 has the further advantage of facilitating the utilization of a stopper, in that its supporting assembly can be mounted in a substantially parallel relation along the vessel instead ofthe customarily inclined relation with respect-to and along its outer side or barrel.

In the construction of FIGS. 2 and 3, the vessel 10 has an outer metal structure that is secured by simple means, such as weld metal, to thebarrel, main side wall or shell of metal construction II. Upper, open end or mouth portion Ila has a mouth or nose ring assembly consisting of parts or members 12, I3 and I4 mountedin a secured relation on and along its upper edge. Member or part I2 is a flat or horizontal annular rim flange that is secured somewhat centrally on the upper edge of I la to project inwardly and form an upper limit support for side refractory lining and to project outwardly for reinforced mounting, as accomplished by angle or ear pieces or parts 14 that are mounted in a peripherally spaced-apart relation about the ladle l0 and in an edge weld-secured relation to the underside of the member l2 and to the outer side of shell wall 11. It willbe noted that in its mounting on the mouth portion 110, the annularrim 12 defines a 'I shape therewith. The rim member 12 is further reinforced by angle-shaped annular member 13 whose bottom leg is shown as having the same extent and as secured in a face-to-face relation with the upper surface ofjthe member 12. Peripherally spaced-apart gussets 13a reinforce the member 13.

The metal bottom shell wall portion llb is shown of rounded or convex shape but may be flat, if desired, depending upon the type of refractory bottom lining 21 that is to be used. The bottom wall portion llb may, as shown in FIG. 2, be secured as by rivetsl5, to project below and close-off the bottom of the barrel or side wall ll. 7

A pair of oppositely-extending trunnions or trunnion pins 30 is provided and is mounted intermediate top and bottom end portions of the shell 11, substantially centrally of the vessel 10. In this connection, block means having a pair of oppositely-positioned trunnion circular segments or block members 25 that are formed complementary to the curvature of the shell I1, are mounted in a secure abutting relation against its outer face. Each block 25 may be pressure-formed or rolled from a rectangular piece of heavy plate or sheet metal materialfA mounting spindle orbutt end portion 300 of each trunnion 30 is secured within an associated block member 25 to support an outwardly-projecting flanged mounting or bearing portion 30b The portions 30b of the pair of trunnions may be engaged by a pair of arms or jibs of a casting crane, or by hook ends of a bail to rotatably-mount and support the ladle 10 in a suitable operating relation for receiving molten metal from the spout of a furnace and for delivering it into molds. It will be apparent that the ladle 10 can be tilted as desired for facilitating the pouring of metal and the removalofa slag blanket, etc.

The central block members 25 are reinforced or strengthened in their positioning by upper and lower barrel bands or rings 26a and 26b that engage their upper and lower edges and are secured, as by weld metal, to and about the outer surface of the shell 11. A further bottom reinforcement is represented by a pair of rest stand members or pieces 27 of tioned immediately below each of the trunnions 30 to rest against barrel bottom band or ring 2611; it is secured to the outer surface of the shell wall I1.

The vessel 10, as illustrated in FlGS.-2 and 3, represents a ton capacity ladle of the vertically or longitudinally straight metal side wall or body construction of the invention. It will be notedthat the flange member 12 and that the nose ring angle member 13 may be rolled without any special shaping or compensation for variable diameters of the shell wall 11. .As shown in FIG. l, a vessel 10 of the inventive construction may be provided with a slightly greater depth or length to give it the same capacity as a conventional inclined shell wall furnace 9. Further, in accordance with the invention, the upper and lower rings 26a and 26b are made of identical construction and may consist of rolled bars with no special preparation on their inner diameters to match a slope of a shell wall. This results in a sizable cost reduction as does the fact that each trunnion block member 25 of rather heavy construction can now be a simple rectangle that is rolled or pressed to the shell radius. Heretofore, it has been necessary to form trunnion blocks as casting. There is no need for machining top and bottom surfaces at an angle to match an inclined shell wall or to develop an are along the top and bottom to form a flat. The inner bore of the block members 25 is now straight rather than-angular. The blocks, depending upon the peripheral size of the vessel, may be two in number (shown) and corresponding in positioning to the trunnions 30, or may be of any suitable number, with their end portions in spaced alignment and with their inner sides weld-secured in position on the shell 11. The trunnions 30 no longer require vertical slope on their butt ends to match the shell angle and only a simple substantially right angle cutoffis now necessary.

Extensive plate layout is no longer required for the metal shell wall and the time consuming fitting is eliminated. Plate rolling is simplified, since all sections or members can now be identical and automatic seam welding time is simplified. The straight sided molten metal processing ladle utilizes nose and barrel members or parts including trunnion block means, ladle rest means, and a pair of oppositely extending trunnion pins secured about and fitted on the metal shell without the use of angular matching surfaces or costly slopes. Extensive ladle plate layout for the metal shell is unnecessary and identical plate sections are used. Briefly, the time is greatly reduced in plate preparation, machining, layout and fitting-up and a saving of about 25 percent in manufacturing cost has been attained. In addition to these and other advantages mentioned, a straight-sided type of metal body tends to better equalize temperature induced expansion and contraction forces exerted thereon.

As illustrated particularly in FIGS. 2, 3 and 4, the inner area and particularly, the lower portion of the inner area of shelllike metal body ll, is effectively provided with a downwardlyconverging frustoconical contour or shape by the application of a refractory plastic lining or layer 24 that may be applied as a ccmentitious mix by a nozzle under pressure, by trowel or other suitable means, or by providing an inner mold wall and pouring it into position. The material is then permanently set and bonded as a solid lining along the inside or inner wall of 11 to provide a contoured mounting wall for inner refractory brick or tile members forming an inner protective lining of the ladle. The reference material can be air-set, with or without the application of heat. By providing an intermediate permanently set lining or layer 24 that is resilient in its mounted relation, that is tightly permanently bonded to the inside of the metal shell wall 11, and that provides a solid thickness of lesser extent and of better heat conductivity than the-associated inner refractory lining, l have been able to provide a requisite inside convergence for the molten metal. receiving cavity in a simplified and less expensive and more practical type ofmetal body construction.

In the embodiment of FIG. 2, the intermediate permanently set lining 24 extends substantially fully along the metal vertical wall 11 to bottom metal wall llb, with a gradually increasing thickness towards its downward reaches. In the embodiment of FIG. 4, intermediate lining 24' extends from a position immediately below the trunnion shaft butt end portions 30a, and in the embodiment of FIG. 5 intermediate lining 24" extends from a spaced position below the trunnions 30 and 'starts immediately below the ring rests or stands 27 of the trunnion mountings. The construction of FIG. 2 is advantageous from the standpoint of giving a taper along the full extend of the vessel for the removal of skull, etc. The constructionsof FIGS. 4 and 5 are advantageous from the standpoint that they simplify the construction, particularly of the brick or tile work and, at the same time, provide'the lower portion ofthe vessel with a slope that enables removal of skull.

In the embodiment of FIG. 2, upper refractoryvertical brick or tile rows or band 20 as'well as lower vertical rows or band 22 have a vertically sloped mounting. In the embodiment of FIG. 4, the upperband portion 20 requires a radius of the brick rows only from a point below the trunnion shaft 30 at which permaset lining 24' begins. In the embodiment of FIG. 5, the upper brick band portion 20" may in section have a uniform or vertically straight-sided construction fully along its extent down to the next lower series of vertical brick or tile members carried by intermediate band 23. Bands 23 and 22" will have a built-in slope down into bottom brick or tile assembly 21.

It will further be noted that, in the embodiment of FIG. 5, an additional band 23 is provided. However, in all the embodiments, the vertical bands 20,20 and 20 are shown as having a substantially uniform thickness that is less than the thickness of the next adjoining lower bands such as represented by 22, 22' and 23 and by 22" with reference to 23. In the case of the embodiment of FIG. 5, the vertical band 23 has a uniform thickness which is greater than the thickness of the vertical band 20 but less than the thickness of the lowermost vertical band 22". In all the embodiments, the lower vertical band 22, 22' or 22" may be of comparable or slightly less thickness than the bottom portion 21.

It is apparent that the refractory brick or tile lining portions or bands are, in effect, mounted against and backed-up by the intermediate lining 24, 24 or 24 and by the inside inner wall of the metal body portions 11 and llb THe material of the intermediate lining or tile mounting layer is of a type that will not evaporate under vacuum at higher temperatures, thus enabling the ladle to be used for continuous casting and vacuum melting operations as well. In addition to providing an inner contouring ofthe metal shell wall 11 as a permanent part thereof, the lining 24 acts as a shock absorber between the innermost refractory lining and the metal shell wall 11 and, if chipped or otherwise damaged during the repair or replacement of brick or tile members, can be easily patched and then permitted to set before used as a backup for brick or tile members being replaced. Although intermediate lining 24, 24' or 24" may be slightly damaged during patching of the tile members, it will not separate from the metal shell wall 11 or change its shape when preset in a bonded position therealong. It is preferable to provide the intermediate or filler monolith refractory lining about 24 hours setting time before the innermost refractory brick members are built-up to complete the construction.

FIG. 6 illustrates the use of a refractory brick or tile lining 20" that is smooth throughout its inner longitudinal extent, as compared for example, with the stepped construction of the lining 20 of FIG. 2. It also illustrated the preferable use of U- shaped metal clips, ties or anchors 35 that are welded to an inner side of the metal shell wall 11 at randomly spaced-apart locations thereon. Among other things, the anchors 35 prevent loosening the filler material of the monolith lining 24 during rough shipment or handling. By way of example, the clips or anchors 35 may be of stainless steel, have a spaced relation of about 18 inches, a height of about I to 1- /2 inches and a length of about 3 inches; they are, in effect, buried or imbedded in the castable material of the intermediate or filler lining 24.

It is highly important that the filler lining 24 have a heat conductivity that'isless than that ofthe refractory brick innermost lining as well as less than that of the metal shell outer wall, such that it will function to effectively retain heat; it should also be fully lined or enclosed and thus protected from the molten metal, etc., on its inner side by the replaceable tile or brick members. The monolith refractory lining is shown fully closed-off by the refractory tile members and the metal construction. It has been determined that the intermediate refractory lining not only increases the life of the refractory brick and the metal shell wall, but materially limits heat loss from the molten metal being handled. Also the refractory tile or brick innermost lining has a more uniform and constant temperature, and the outer metal shell wall has a lower and more constant temperature. Advantageous features of the use of such an intermediate lining extend to ladle bottle, torpedo cars, etc. It is thus apparent that the refractory monolith lining enables the use of a metal outer shell-like body that has a uniform cross section along its length or sectional dimension, whether of ova'l or cylindrical shape. It eliminates the need for a tapered or frustoeonical construction or shape of the metal body.

Although I have shown and described specific embodiments of my invention, it will be apparent to those skilled in the art that various changes and modifications may be made in the illustrated structure without departing from its spirit and scope.

Iclaim:

I. In an improved ladle ofa minimum capacity of about 50 tons for receiving, holding and discharging molten metal and having a normally upright operating position, a verticallyelongated enclosing shell-like metal outer body of substantially the same sectional dimension along its elongated extent and having a closed bottom end portion and an open mouth top end portion, a pair of trunnions extending from opposite sides of said body and having means securely mounting them intermediate said top and bottom end portions, a permanently set lining of poorly conductive refractory material mounted along the inner side of said shell-like body and extending from an upper portion thereof in an inwardly-converging manner towards said bottom end portion thereof to define a frustoconical inner shape within said body that converges towards said bottom end portion, replaceable refractory tile members fully lining the inside of said body from the open. mouth top end portion to and along said closed bottom end portion, and said refractory tile being mounted along the in side of and closely-off said permanent lining and therewith defining a downwardly-converging substantially frustoconicalg metal receiving cavity within the ladle.

2. In an improved ladle as defined in claim 1, said refractory tile having a greater thickness below said mounting means for said trunnion pins and into and along said closed bottom end portion. I 4 I 3. In an improved ladle as. defined in claim 1, said permanently set lining extending along the inside of said shell-like body from a position below said open mouth top end portion and adjacent said mounting means for said pair of trunnion 131115.

4. In an improved ladle as defined in claim 1, said permanently set lining extending from below said mounting means for said trunnion pins and with gradually increasing thickness towards said bottom end portion of the ladle.

5. in an improved ladle as defined in claim 1, said permanently set lining being applied to and being securely set in position along said shell-like body beforesaid refractory tile is mounted. and said refractory tile members having a replaceable mounting with respect to said permanently set lining.

6. In an improved ladle as defined in claim 5, said permanently set lining being sprayed on the inner side of said 1 shell-like body and being resilient and set in a bonded relation therealong.

7. In an improved ladle as defined in claim 5, metal anchors secured to project from an inner side of said metal outer body and being imbedded in'said permanently set lining.

8. In an improved ladle for molten'f'errous metal having a minimum capacity of about 50 tons and having a normally upright operating position for receiving and holding molten metal therein, a vertically-elongated substantially cylindrical to oval shaped metal shell-like body of the same cross-sectional dimension along its elongated extent and having a closed bottom end portion and an open mouth top end portion, trunnion block means having a pair of oppositely-positioned block portion curved to correspond with said cylindrical shell-like body and secured to an outer side thereof inter-' other of said block portions for positioning and rotatablymounting the ladle, a pair of circular banding members about the outer periphery of said shell-like body in a vertically s spaced-apart relation with each other, said banding members being secured to said body and to upper and lower edges of of circular segmental shape, each of said trunnion pins having a butt end portion extending into the block portion within which it is mounted, each of said trunnion pins having an outwardly-projecting bearing portion, a pair of stand members of circular segmental shape, said stand members being secured to said body in supporting abutment with a lower one of said' banding members, one of said stand members being mounted below one of said block portions, and the other of said stand members being mounted below the other of said block portions.

10. In an improved ladle as defined in claim 8, said permanent lining being of preset monolith refractory material and.

extending from a position below said open mouth top portion in an inwardly-converging manner to said closed bottom end portion to define a substantially frustoconical inner wall, and said refractory lining being mounted on said wall to define the downwardly-converging molten metal receiving cavity.

11. in an improved ladle ofa minimum capacity ofabout 50 tons for receiving, holding and discharging molten metal, an elongated enclosing shell-like metal outer body, a permanently set refractory monolith lining anchored along the inner side of said metal outer body, replaceable refractory tile members fully lining the inside of said monolith lining and said body to define a molten metal receiving cavity within the lawall within said body, and said refractory tile members being mounted over said monolith lining to conform thereto and define a frustoconical molten metal receiving cavity with the ladle.

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