US3681818A

US3681818A - Sagger

Info

Publication number: US3681818A
Application number: US106141A
Authority: US
Inventors: Louis Di Stefan
Original assignee: Individual
Current assignee: Individual
Priority date: 1971-01-13
Filing date: 1971-01-13
Publication date: 1972-08-08
Anticipated expiration: 1989-08-08
Also published as: CA960843A

Abstract

A sagger particularly for baking carbon or graphite bodies comprises a shell mounted on a supporting base and having a removable bottom or closure member secured in closed position by means of wedge members. The wedge members may be removed after the body is baked, thereby allowing the closure member to drop, thus facilitating removal of the sagger contents. The shell is provided with plow members extending inwardly thereof adapted to fragment and loosen the packing medium surrounding the body when the shell is removed from the sagger contents.

Description

United States Patent Di Stefan SAGGER [72] Inventor: Louis Di Stefan, 8235 Buffalo Ave.,

, Niagra Falls, N.Y. 14304 3 Aug. 8, 1972 684,980 12/1952 Great Britain ..25/153 Primary Examiner-J. Spencer Overholser Assistant Examiner-Ben D. Tobor [22] Filed: Jan. 13, 1971 Attorney Ashlan F. Harlan, Jr.

21 l. N I 1 App 57 ABSTRACT 52 us. Cl. ..2s/1s3, 220/55 Y, 263/47 R A e Particularly baking graphite 51 Int. Cl ..F27d 5/00 bdles compnsesr a 3 suppomng 581 Field of Search ..25/153 120- 263/47 R base and having a removable clsure member secured in closed position by means of wedge 56 R f members. The wedge members may be removed after 1 e erences l the body is baked, thereby allowing the closure UNITED STATES PATENTS member to drop, thus facilitating removal of the sagger contents. The shell is provided with plow memggf bers extending inwardly thereof adapted to fragment and loosen the packing medium surrounding the body FOREIGN PATENTS OR APPLICATIONS when the shell is removed from the sagger contents, 340,376 1/1931 Great Britain ..25/ 153 7 Claims, 3 Drawing 4 0w 4 2 g 11% 20 20 W 7 r l a U 78 75M f SAGGER BACKGROUND OF THE INVENTION This invention relates to saggers for containing carbon or graphite bodies during baking and, more particularly, to saggers which can be readily emptied of their contents after the baking process.

In the art of baking pitch or'tar bonded carbon and graphite bodies, such, for example, as small electrodes, it has been the practice in recent years to individually pack the green bodies in saggers which support and prevent distortion of the bodies in the heating furnace during baking. The saggers consist of suitably shaped metal containers having dimensions slightly larger than the bodies to be baked. A suitable granular packing material is placed in the sagger between the green body and the inner walls of the sagger so as to completely surround and support the body. Advantages residing in the use of saggers are the greater ease of packing, loading, and unloading the pieces with mechanized equipment. Also, heat is distributed more evenly around the piece being baked thereby producing a uniformly baked, finished product.

One critical problem encountered in the use of saggers, however, is the removal or discharging of the baked bodies from the saggers. The tars, hydrocarbons, and other residues driven from the carbon bodies during the baking process filter into the packing material and tend to condense therein during subsequent cooling, thereby bonding together the particles of the packing material. Consequently, when the saggers are tipped or turned over to discharge the baked carbon bodies, the bonding of the packing material interferes with and impedes the removal of the baked bodies. Very often, the saggers must be beaten with hammers or dropped several times against the floor surface to loosen the bonded packing material enough to permit removal of the bodies. As a result, not only is costly labor time expended in the task of removing the baked bodies from the saggers, but also repair or replacement of the saggers is frequently necessary, thus increasing the overall costs of the baking operation.

SUMMARY OF THE INVENTION The present invention, as hereinafter described, provides a solution to the above problem by providing a new and improved sagger, which is simple and strong in construction, low in cost, rugged and durable in use, and which includes a removable bottom wall or closure for facilitating the removal of the baked body from the sagger.

. Generally speaking, a sagger according to the present invention comprises a container having a shell and a removable bottom or closure held in closed position by wedge means. A plurality of plow members extending inwardly from the walls of the container adjacent the bottom thereof provide reinforcement for the container bottom construction and also serve for loosening the hardened packing material during removal of the sagger shell, thus facilitating removal of the baked bodies.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a vertical sectional view of a sagger constructed in accordance with the principles of this inven- 2 tion showing the packing medium disposed within the interior of the sagger around a carbon body;

FIG. 2 is a fragmentary vertical sectional view, on an enlarged scale, showing details of the bottom wall or closure member and the packing medium fracturing means or plow members incorporated in the sagger of this invention; and

FIG. 3 is a bottom plan view, on an enlarged scale, of the sagger shown in FIG. 1.

DETAILED DESCRIPTION OF A PREFERRED. EMBODIMENT Referring now in detail to the drawings, and particularly to FIG. 1, there is shown a sagger, constructed in accordance with the present invention and comprehensively designated 10, comprising a cylindrical, tubular shell 12 formed of a suitable metal, such as, for example, certain stainless steels and wrought iron, capable of withstanding without substantial warping temperatures of the order of 500 to 2,500 F. While the shell 12 is preferably cylindrical as shown in the drawings, it should be understood that it may take various crosssectional configurations within the purview of this invention. Also, the diameter and length of shell 12 may vary as dictated by the size of the particular bodies for which it is intended. It will be understood that the terms upper and lower" and similar tenns of position are used hereinafter for convenience with reference to the structure as shown in FIG. 1, but are not intended to indicate or require any definite position for the novel sagger of the present invention in use.

A tubular reinforcing ring 14 is welded or otherwise fixedly secured to the bottom end of shell 12 and encircles the bottom, outer peripheral surface thereof. The reinforcing ring 14, which serves as a supporting base for the shell, extends axially below shell 12 and terminates in an annular ground or floor engaging surface 16. As shown in FIG. 2, the ring 14 is preferably sub- I stantially thicker than shell 12, thus providing adequate support for the latter and adding rigidity and strength thereto. The'ring 14 may be composed of any suitable, strong, durable, heat-resistive metal such as RA 330 stainless steel, for example. A plurality of arcuately shaped plates 18 are welded or otherwise fixedly secured to the outer peripheral surface of ring 14 at circumferentially spaced intervals therealong, these plates projecting outwardly for facilitating the lifting and handling of the sagger 10.

An annular ring 20 is rigidly secured to the inner wall surface of the shell 12 adjacent the bottom thereof, by suitable means, welding, for example. As best shown in FIG. 2, the ring 20 forms a flange extending radially inwardly a short distance from the shell 12 and serves as an abutment adapted to be engaged by a removable bottom wall or closure member 22 as hereinafter described. A plurality of triangular gusset plates or plow members 24 are rigidly secured, for example by welding, at the juncture of the shell 12 and annular ring 20 at circumferentially spaced intervals, thus providing a rigid construction. The ring 20, gusset plates 24, and removable closure member 22 are preferably formed of the same metal as the shell 12. The member 22, however, is materially thicker in order to support the sagger contents. The closure member 22 is shaped to conform to the cross-section of the shell 12 and has a diameter slightly less than the inside diameter of the shell for ease of assembly and removal.

As shown in FIGS. 1 and 3, a plurality of angle members 26 are rigidly secured, by suitable means such as welding, to the bottom surface or face of closure member 22, extending downwardly therefrom and terminating at a level spaced above the floor engaging surface 16 of ring 14. These angle members 26 serve as supporting legs for the closure member 22 when the latter is disengaged from the shell 12. While four such angle members 26 are shown in the illustrated embodiment with their respective legs defining comers of a square pattern, it should be understood that the principles of this invention contemplate the use of any number of supporting members 26 of any desired shape and arranged in any pattern desired, so long as they provide the requisite support for closure member 22.

Means are provided for releasably securing the bottom wall or closure member 22 in place, such means comprising a plurality of wedge members 30 extending radially outwardly through corresponding slots 32 located in the reinforcing ring 14 just below the member 22 when the latter is in place. Each wedge member 30 is preferably formed of the same metal composition as the ring 14 and is provided with a straight side edge or surface 34 facing upwardly toward the lower face of the closure member 22 and a tapered side edge 36 facing downwardly. A handle 38 projects laterally outwardly from opposite sides of each of the wedge members 30 for manually gripping and manipulating the members.

in assembling the sagger, the wedge members 30 are driven radially outwardly from within the reinforcing ring 14 through the slots 32, causing the side edges 34 of the wedge members 30 to bear upwardly against the closure member 22. This forces the annular edge of the upper face of the closure member tightly against the bottom surface of annular ring 20, thus preventing leakage around the edges. In the assembly operation, care must be taken to so place the closure member 22 that the supporting legs 26 thereon do not interfere with driving the wedges 30 into the slots 32.

In packing a carbon or graphite body to be baked in the assembled sagger 10, a granular packing medium 40 is placed in the bottom of the sagger on closure member 22. The green body 42 of carbon or graphite is then placed in the sagger on top of the layer of packing medium and more packing medium is deposited in the sagger around and on top of the green body to completely cover the green body and fill the space between it and the walls of the sagger as shown in FIG. 1. The sagger may then be lifted by suitable handling or lifting equipment engageable with the plates 18 and placed in a conventional heating furnace for baking the body.

The packing medium 40 may be formed of any suitable and desired granular material, such as granular petroleum coke or sand, for example. Since the packing medium is porous, it permits the escape of volatiles given off from the binder of the green body during baking and at the same time serves to absorb excessive binder which sometimes exudes from the green bodies in the early stages of baking. Also, the packing medium is effective to provide more uniform heating of the body which it surrounds.

After the baking process, the sagger 10 is removed from the furnace and placed either on a floor surface or a suitable conveying arrangement leading to a sagger disassembly station. The wedge members 30 are driven radially inwardly through the slots 32 to free the closure member 22 and allow it to drop by the weight of the sagger contents and gravity until the depending angle members 26 engage the floor surface. The shell 12 is then lifted suddenly upwardly relative to the sagger contents by means of a crane or other suitable equipment engageable with the plates 18. The jolt or impact tends to fracture the hardened packing medium 40 supported on the closure member 22. As the shell 12 is lifted the plow members 24, carried by the shell, out through the packing medium 40 so that when the shell 12 is completely removed, the packing medium is readily removed from about the baked body.

The present invention thus provides a novel and simple sectional sagger having a removable closure member for facilitating the removal of the sagger contents. By the provision of the stiflener brackets, serving as plow members, extending inwardly of the sagger shell, the hardened packing medium is fragmented and loosened during removal of the shell to facilitate separation of the baked body from the packing medium. It will be understood that the bottom walls or closure members 22 may be interchangeable for all saggers of the same shape and diameter. it will also be understood that the present novel saggers may be used in baking not only a single carbon or graphite body contained therein, but also a plurality of such bodies packed in the sagger with packing medium surrounding each body.

As preferred embodiment of this invention having been hereinabove described and illustrated in the drawing, it is to be understood that various modifications thereof can be made without departing from the broad spirit and scope of this invention as defined in the appended claims.

I claim:

1. A sagger adapted to contain a green body to be baked and a granular packing medium surrounding said body comprising: a tubular base having a floor engaging surface at the lower end thereof, a tubular shell carried by the upper end of said base, said shell having a peripheral flange extending inwardly of said shell adjacent the lower end thereof; a removable closure member having opposite faces, one of said faces being provided with a peripheral portion engageable with said flange to close said lower end of said shell; means releasably holding said closure member against said flange in the closed position of said closure member; and means secured to the inner surface of said shell adjacent said lower end for fracturing the packing medium surrounding said body upon removal of the shell from the sagger contents.

2. A sagger according to claim 1 wherein said releasably holding means comprises a plurality of wedge members extending through corresponding slots in said base and each wedge member having a surface in bearing contact with said other face of said closure member.

3. A sagger according to claim 1 wherein said closure member has a plurality of supporting legs depending from the other face thereof, which legs terminate in end portions spaced inwardly of the floor engaging surface of said base when said closure member is in closed position.

4. A sagger according to claim 1 wherein said fracturing means comprise a plurality of spaced plow members extending inwardly of said shell adjacent said flange.

5. A sagger according to claim 1 wherein said shell is cylindrical in shape and said base is circular in crosssection and rigidly secured at the upper end thereof about the peripheral surface of said shell adjacent the lower end of the latter.

6. A sagger according to claim 5 wherein said flange is comprised ofan annular ring rigidly secured along its outer peripheral edge to the inner wall surface of said shell adjacent the lower end of the latter.

7. A sagger according to claim 2 wherein said closure member has a plurality of supporting legs depending from the other face thereof, which legs terminate in end portions spaced inwardly of the floor engaging surface of said base when said closure member is in closed position, wherein said fracturing means comprises a plurality of spaced plow members extending inwardly of said shell adjacent said flange; wherein said shell is cylindrical in shape and said base is circular in crosssection and rigidly secured at the upper end thereof about the peripheral surface of said shell adjacent the lower end of the latter; and wherein said flange is comprised of an annular ring rigidly secured along its outer peripheral edge to the inner wall. surface of said shell adjacent the lower end of the latter.

Claims

5. A sagger according to claim 1 wherein said shell is cylindrical in shape and said base is circular in cross-section and rigidly secured at the upper end thereof about the peripheral surface of said shell adjacent the lower end of the latter.

6. A sagger according to claim 5 wherein said flange is comprised of an annular ring rigidly secured along its outer peripheral edge to the inner wall surface of said shell adjacent the lower end of the latter.

7. A sagger according to claim 2 wherein said closure member has a plurality of supporting legs depending from the other face thereof, which legs terminate in end portions spaced inwardly of the floor engaging surface of said base when said closure member is in closed position, wherein said fracturing means comprises a plurality of spaced plow members extending inwardly of said shell adjacent said flange; wherein said shell is cylindrical in shape and said base is circular in cross-section and rigidly secured at the upper end thereof about the peripheral surface of said shell adjacent the lower end of the latter; and wherein said flange is comprised of an annular ring rigidly secured along its outer peripheral edge to the inner wall surface of said shell adjacent the lower end of the latter.