US3211443A - Metal holding receptacle - Google Patents

Description

1955 B. M. STARNE-R ETAL 3,211,443

METAL HOLDING RECEPTACLE 4 Sheets-Sheet 2 Filed April 15, 1962 21s (-3 'lll" R S B S R O S J N E MPV 6 N I 4 M AL NN R ET DDS T T E R R A J L E 0 N ATTORNEY United States Patent 3,211,443 METAL HOLDING RECEPTACLE Bernard M. Starner, New Kensington, Stanley C. Jacobs,

Arnold, and Noel Jarrett, New Kensington, Pa, assignors t0 Aluminum Company of America, Pittsburgh,

Pa., a corporation of Pennsylvania Filed Apr. 13, 1962, Ser. No. 187,336 13 Claims. '(Cl. 266-39) This invention relates to the handling of molten metal and it is particularly concerned with an improved construction of receptacles for holding molten aluminum and aluminum base alloys which minimizes heat loss through the walls thereof.

In the art of melting, remelting and transferring metals, especially light metals, such as aluminum and aluminum base alloys, it is often necessary or desirable to hold the molten metal for a period of time in connection with the processing thereof and to prevent a rapid cooling through the walls of the holding vessel. It is also important that the receptacle walls do not contaminate the metal and that the receptacle walls be leakproof. In some cases it is further necessary or desirable to provide a cover having heating means therein which can quickly melt any solidified metal. The objects of the present invention are directed to the construction of such types of receptacles that are particularly designed for the maintaining and holding of molten aluminum and aluminum base alloys under conditions where heat losses through the walls of the receptacles must be kept to a minimum and leakage and melt contamination are avoided.

Other objects and advantages of the invention will become apparent from the following specification and claims and from the appended drawings which illustrate a preferred embodiment of a vessel for containing molten aluminum and aluminum base alloys and incorporating the principles of the invention.

Referring to the drawings:

FIGURE 1 is a side elevation of a receptacle incorporating the principles of this invention.

FIGURE 2 is a plan view of the receptacle shown in FIGURE 1 with the cover in place.

FIGURE 3 is another side elevation of the receptacle illustrated in FIGURE 1 showing the tapping spout.

FIGURE 4 is a plan View of the receptacle with the cover member removed therefrom.

FIGURE 5 is a vertical section as taken on line 5-5 of FIGURE 2 with the cover member illustrated as slightly separated from the base portion thereof.

FIGURE 6 is a section on the line 66 of FIGURE 4.

FIGURE 7 is a section on the line 77 of FIGURE 4.

FIGURE 8 is an enlarged section as taken on the line 88 of FIGURE 4.

FIGURES l to 4 clearly illustrate a suitable external configuration of a presently preferred construction incorporating the principles of this invention and particularly adapted for the holding of aluminum and its alloys under conditions where heat losses through the walls of the vessel are kept to a minimum. As there illustrated, the subject construction broadly includes a cylindrically shaped base portion, generally designated 10, adapted to contain a charge of molten metal, suitably aluminum and its alloys, provided with a tappable pouring spout 12 to efi'ect liquid metal removal therefrom and an associated 3,Zll,443 Patented Oct. 12, 1965 ICe slightly dome shaped removable cover member 14 having an axially located burner assembly, generally designated 16, mounted in the apex thereof.

Referring now also to FIGURE 5, the base portion 10 of the subject construction includes an externally disposed metal shell, suitably steel, and a multilayer multifunctional lining therefor arranged to achieve the objects set forth above. The metal shell is desirably formed of a fiat horizontally disposed circular base plate 18 supported by a plurality of spaced parallel and chordally disposed I-beams 20, an angle iron 22 peripherally secured to the base plate 18, as by welding, and which, in turn, has its vertically disposed extending leg secured, as by welding, to the lower end of a vertically disposed cylindrically shaped side wall member 24. The upper edge of the side wall member 24 has peripherally secured thereto an externally disposed angle iron 26, the extending leg 28 of which serves as an outwardly extending cover mem ber supporting flange and sealing surface. Disposed in uniformly spaced relation around the periphery of the upper end of the side wall member 24 and extending outwardly from the underside of the flange 28 are a plurality, suitably three in the illustrated embodiment, of cover member positioning bosses 30. As illustrated, the cover member positioning bosses 30 are apertured to selectively receive complementally spaced cover member positioning pins 32 when said removable cover member 14 is properly positioned in vessel closing relationship on said body portion 10.

As mentioned earlier and as best shown in FIGURES 4 through 7, the body or molten metal containing portion 10 of the subject vessel is provided with a multilayer multifunctional lining for the maintaining and holding of aluminum and its alloys under conditions where heat loss through the walls thereof is held to a minimum and wherein leakage and contamination of the contained metal is minimized, if not actually avoided. To this end, the lining generally includes a relatively thick outer portion or course of high temperature insulation material disposed in abutting relation with the base plate 18 and side wall plate 24. Extending over the entire inner face of the insulation course is a continuous compacted layer of granular refractory material of a character that is not wetted by or reactive with molten aluminum when in contact therewith. Interiorly adjoining the layer of granular refractory material and serving to hold it in place is a facing course of a high temperature refractory material of a character that will not contaminate the molten metal with impurities. Adjacent the top of the multilayer lining is an interiorly disposed channel for accommodating heating means to aid in minimizing any freezing on or near the surface of the body of molten metal being held in the vessel.

It should be appreciated that the construction here described is not designed for the melting of cold charges as are conventional melting furnaces but for holding a molten charge over a period of time.

As will be apparent to those skilled in this art, the hereinafter described details of preferred construction are most conveniently described in conjunction with the sectional views of FIGURES 5-7, it being understood that such illustrated and described construction will extend, with the exception of the pouring spout area, symmetrically around the described cylindrical vessel.

More specifically, the relatively thick outer portion of the multilayer lining is preferably formed of suitable high temperature insulation blocks and includes a basal multilayer insulator lining supported by the upper surface of the base plate 18 and suitably formed of at least two layers or courses 34, 36 of closely abutting suitable high temperature block insulation. Peripherally mounted on the upper surface of the base insulating course 34 and disposed in abutting relation with the side wall member 24 is a vertically disposed course 38 suitably formed of arcuately shaped high temperature block insulation of the type employed for the basal courses 34 and 36, suitably asbestos type material such as Carey Hi-Temp as manufactured by the Carey Mfg. Co., and having a horizontal or radial extent of similar or greater thickness than that of the composite basal insulating layers or courses 34, 36. As best illustrated in FIGURES -7, the peripherally disposed outer course 38 upwardly terminates a predetermined distance below the top of the shell side wall 24.

Disposed within the above described outer course and in abutting relation with the inwardly facing surfaces thereof is an intermediate continuous compacted sealing layer or course of granular material of a character that is not wetted by or reactive with molten aluminum when in contact therewith, such as silicon carbide, calcium oxide, graphite or aluminum nitride, preferably ore grade alumina. The vertically disposed cylindrical portion of the intermediate granular course 40 upwardly terminates at a location slightly below the upper portion of the outer course 38. Mounted thereon is a refractory annulus 42 of a calcium aluminate bonded alumina refractory, either formed of segmental blocks or cast in place, and of sufficient thickness to bring the upwardly facing surface thereof coplanar with the upwardly facing edge of the outer insulating course 38.

Disposed within the above described intermediate granular course 40 and in abutting relationship therewith is an inner shell formed of a basal multilayer course 44, 46 constituted by blocks of suitable high temperature refractory material which will not contaminate the molten metal with impurities, suitably a silicon nitride bonded silicon carbide refractory such as Refrax as manufactured by the Carborundum Co., and a peripheral course 48 of the same material. The peripheral course 48 upwardly terminates at a location above the upper terminus of the outer insulation course 38 but below the top of the outer shell 24, suitably at a location intermediate thereof. As illustrated, the base of the course 48 is supported by the periphery of the basal course 44. The upper basal course 46 peripherally terminates a predetermined distance inwardly of the inner surface of the course 48 forming an annular recess 50 therebetween. Such recess is filled and closed by an overlying cast in place annular triangularly shaped fillet 52 of a calcium aluminate bonded alumina refractory having a slope sufficient to assure thorough drainage of the receptacle defined by the above described construction.

In order to minimize undesired freezing adjacent the surface of a body of molten metal disposed within the above described vessel, heating means are incorporated around the top peripheral portion of the multilayer lining. The preferred constructional details of a suitable arrangement thereof are best illustrated in FIGURES 6 and 7. As heretofore described, the upper termini of the vertically disposed courses 38 and 48 in conjunction with the cast annulus 42 and the outer shell 24 define an annular recess generally designatable 60. Disposed within this recess and adjacent the outer shell 24 is an annular gas manifold 62 having a plurality of inwardly directed and radially disposed burner pipes 64 connected thereto. Mounted at the ends thereof are stainless steel burner heads 66 which open into an annular chamber 68 defined in part by the annulus 42, the outer surface of the course 48 and the inwardly facing surface of a cast in place annulus 70 of a suitable insulating material such as a low density refractory silica brick such as Harbison-Walker No. 26 or a light weight silica castable, which surrounds the manifold 62 and burner pipes 64. The annular chamber 63 is vented to the interior of the receptacle by means of a plurality of transverse radially disposed channels 72 positioned intermediate the burner heads and formed in the underside of an overlying insulation cap 74. The insulation cap 74 is preferably formed by segmental blocks of cast calcium aluminate bonded alumina refractory and is sized and shaped to have its upper surface disposed coplanar with the top of the shell 24 and its bevelled inwardly directed edge 76 disposed in coplanar with the inner surface of the inner core 48.

In the fabrication of the insulation block outer shell and refractory inner shell, the various blocks are preferably secured to each other and to the steel forming members with a suitable fibrous adhesive to both facilitate assembly thereof and to provide an essentially monolithic finished structure. In addition, various liners may be used to preliminarily form the intermediate alumina layer 40 during assembly. Although arcuately shaped block components are preferably employed in the illustrated cylindrical structure, conventional rectangularly shaped components may also be utilized. However, in the latter instance the resulting interstices between component elements and between the component elements and the external metal shell should be filled with crushed material of requisite character to eliminate all voids therein.

As will be apparent from the foregoing, the described multilayer lining is of an essentially monolithic finished character arranged to provide a substantially leakproof structure that holds heat loss to a minimum and minimizes, if not actually avoids, contamination of the contained molten metal. The subject construction also integrally provides for a contained heating means so arranged and located as to minimize any freezing of the surface of the body of molten metal being held in the vessel.

As best shown in FIGURES 4, 5 and 8, the subject receptacle includes a pouring spout assembly 12 for effecting the removal of molten metal therefrom. Such assembly includes an internally disposed casting of a calcium aluminate bonded alumina refractory having a generally conically shaped inwardly flaring aperture 92 communicating with a tap hole 94 therein. The inner surface of the casting 90 is disposed substantially flush with the inner surface of the inner lining course 48 and the lower surface of the aperture 92 is shaped to be coplanar with the upper surface of the basal course 46 at the point of juncture therewith and to slope downwardly therefrom to facilitate flow of molten metal from the receptacle. The tap hole 94 communicates with a tap hole defining ring 96 formed of a high alumina molded refractory disposed within the terminus of a cast iron spout housing member 98 generally in the form of a truncated cone having a terminal flange 100 disposed coplanar with the outer shell 24. The tap hole defining ring 96 is provided with a tap hole bore 102 coaxial with the tap hole 94 which in turn communicates with outwardly flaring conically shaped enlarged bore 104. The outer terminus of the bore 104 merges into the bore 106 defined by the high alumina refractory liner 108 of the removable and preheatable cast iron spout member 110. The spout member 110 is supported by the spout housing member 98 and positioned relative thereto by the introduction and maintenance of a plastic refractory material such as chromethermo-lith heat settable cement as manufactured by Harbison-Walker into all voids therebetween. As illustrated, the casting 90 is sized to extend into abutting relationship with the intermediate granular course 40 and as such, effectively substitutes for the inner courses 44, 46 and 48 in its area of location.

Although the above described heat loss characteristics of the described vessel permits its utilization Without a cover member it may be required or desirable, by process considerations, that the vessel be covered. FIGURES 1 to 3 and 5 illustrate a preferred construction for a removable cover member 14 for the heretofore described vessel. There is provided a cover shell, suitably of steel, including a cylindrical body portion 20% supporting an arcuately shaped roof 202. The base of the body portion 200 is provided with an external peripheral flange 204 having suitable packing material 206 secured to its underside and positioned to engage the upper surface of the peripheral flange 28 on the body portion 20 when said cover member is positioned thereon. The base of the body portion 200 of the cover member 14 is also provided with an annular inwardly directed lining retaining flange or shoulder 208 conveniently formed by the mounting of a circularly shaped angle iron on the interior surface thereof, such shoulder serving as a weight supporting surface when said cover is mounted on the receptacle.

The interior of the cover member 14 is provided with a multilayer lining of refractory material in order to reduce heat loss therethrough and to minimize, if not avoid, contamination of the molten metal. As illustrated in FIGURE 5, a preferred multilayer lining includes a relatively thin, cast in place, first course 210 of a high silica refractory such as Kaolite #20 as manufactured by the Babcock & Wilcox Co. and an overlying thicker cast in place and dome shaped second course 212 of a calcium aluminate bonded alumina refractory, peripherally supported by the inwardly extending shoulder 208. The cover member is also desirably provided with an axially located flat flame type gas burner assembly, generally designated 16, to furnish heat, when desired, by reflection and by radiation from the course 212 to the exposed upper surface of the metal contained within the covered vessel. A plurality of vent pipes 214 extending through the cover member are also provided to permit the escape of the combustion gases resulting from the burner operation.

Manipulation of the cover member is facilitated by a plurality of lifting rings 216 mounted thereon.

Having thus described our invention, we claim:

1. An open top holding receptacle for temporary retention of charges of molten aluminum and aluminum base alloys having enclosure forming side walls and a bottom that serve to substantially reduce leakage of and loss of heat from a contained molten charge therethrough comprising an externally disposed open top receptacle-forming shell and a molten charge confining multilayer lining of substantial thickness therewithin extending over a substantial portion of said side walls and over the entire bottom, said multilayer lining including a relatively thick self-supporting outer course of high temperature insulating material, an inner self-supporting course of noncharge contaminating high temperature and refractory material and an intermediate course supported by said outer and inner courses formed of a continuous compacted layer of granular refractory material of a character that will not be wetted by the molten charge for preventing the passage therethrough of molten charge that has penetrated through said inner course.

2. An open top holding receptacle for temporary reten tion of charges of molten aluminum and aluminum base alloys having enclosure-forming cylindrically shaped side walls and a bottom that serve to substantially reduce leakage of and loss of heat from a contained molten charge therethrough comprising an externally disposed open top receptacle-forming shell and a molten charge confining multilayer lining of substantial thickness disposed therewithin extending over a substantial portion of said side walls and over the entire bottom, said multilayer lining including a relatively thick self-supporting outer shell portion of high temperature insulating material to minimize heat transfer therethrough, an inner self-supporting shell portion of non-charge contaminating high temperature refractory material, an intermediate shell portion formed of a continuous compacted sealing layer of granular material of a character that will not be wetted by or react with the molten charge for preventing passage therethrough of molten charge that has penetrated said inner shell portion and heating means interiorly disposed within said multilayer lining and adjacent the upper terminus thereof for uniformly supplying heat adjacent the exposed upper surface of molten charge contained therein.

3. The holding receptacle as set forth in claim 2 wherein said heating means includes a plurality of burner members disposed within an annulus located radially out wardly of said inner shell, said annulus formed in part by a channeled insulating cap covering said multilayer lining.

4. The holding receptacle as set forth in claim 1 including a removable cover member therefor having auxiliary means for applying heat to the surface of the charge in said receptacle included therein.

5. The holding receptacle as set forth in claim 1 wherein said granular material is alumina.

6. The holding receptacle as set forth in claim 1 wherein said inner course is formed of a silicon carbide base refractory.

7. A holding receptacle for temporary retention of charges of molten aluminum and aluminum alloys having enclosure-forming walls and a bottom that serve to substantially reduce leakage of and loss of heat from a contained molten charge therethrough comprising an upwardly open cylindrically shaped metal receptacle-form ing shell having a horizontally disposed circular base portion and a cylindrically shaped vertical side wall portion, an outer self-supporting lining of high temperature insulating material disposed within said shell and in abutting relation with the base and side wall portions thereof, an inner self-supporting refractory lining layer having a horizontally disposed circular base portion and a cylindrically shaped side wall portion disposed in spaced relation with said first lining and presenting a substantially continuous non-contaminating charge confining surface, a sealing course disposed intermediate said outer and inner layers formed of a continuous compacted layer of granular material that will not be wetted by or reactive with said molten charge for preventing the passage therethrough of molten charge that has penetrated through said inner layer, pouring spout means disposed in fluid communication with said charge containing portion of said receptacle and a fillet of cast-in-place refractory disposed at the junction of the base and side wall portions of said inner layer to assure drainage of molten charge from said charge-containing portion of said receptacle through said pouring spout.

8. The holding receptacle as set forth in claim 7 wherein said inner refractory lining layer is a silicon carbide base refractory.

9. The holding receptacle as set forth in claim 7 including a removable refractory lined cover therefor having auxiliary means for applying heat to the surface of the charge in said receptacle included therein.

10. The holding receptacle as set forth in claim 7 including heating means disposed interiorly adjacent the upper terminus of said multilayer lining for uniformly supplying heat adjacent the peripheral portions of the upper surface of the molten charge contained therein.

11. The holding receptacle asset forth in claim 7 wherein said granular material is alumina.

12. The holding receptacle as set forth in claim 1 wherein said outer course is formed of asbestos base material.

13. The holding receptacle as set forth in claim 7 including a pouring spout assembly for effecting removal of molten charge therefrom, said pouring spout assembly comprising a flanged truncated conical housing section secured to said forming shell and a preheatable spout member removably mounted with said housing section.

References Cited by the Examiner UNITED STATES PATENTS Molique 23288 Hartwick 23277 X Lemmer 26311 X Goetz et a1 26639 Foster et a1 266-33 X JOHN F. CAMPBELL, Primary Examiner.

MORRIS WOLK, Examiner.

Claims (1)

1. AN OPEN TOP HOLDING RECEPTACLE FOR TEMPORARY RETENTION OF CHARGES OF LMOLTEN ALUMINUM AND ALUMINUM BASE ALLOYS HAVING ENCLOSURE FORMING SIDE WALLS AND A KBOTTOM THAT SERVE TO SUBSTANTIALLY REDUCE LEAKAGE OF AND LOSS OF HEAT FROM A CONTAINED MOLTEN CHARGE THERETHROUGH COMPRISING AN EXTERNALLY DISPOSED OPEN TOP RECEPTACLE-FORMING SHELL AND A MOLTEN CHARGE CONFINING MULTILAYER LINING OF SUBSTANTIAL THICKNESS THEREWITH EXTENDING OVER A SUBSTANTIAL PORTION OF SAID SIDE WALLS AND OVER THE ENTIRE BOTTOM, SAID MULTILAYER LINING INCLUDING A RELATIVELY THICK SELF-SUPPORTING OUTER COURSE OF HIGH TEMPERATURE INSULAT-

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