United States Patent Inventor Appl. No.
Filed Patented Assignee Carllsle 0. Byrd, Jr. Houston, Tex.
Oct. 15, 1969 Dec. 28, 1971 The Carborundum Company Niagara Falls, N.Y.
INTERLOCKING TILE STRUCTURE 5 Claims, 2 Drawing Figs.
US. Cl 263/51, 165/164 Int. Cl F23! 15/02 Field of Search 263/51" [56] References Cited UNITED STATES PATENTS 1,907,852 5/1933 Miller 263/51 1,976,575 10/1934 MacDonald 263/51 Primary Examiner-Frederick L. Matteson Assistant ExaminerTheophil W. Streule Attorney-K. W. Brownell ABSTRACT: An interlocking heat exchange structure comprises a plurality of grooved tiles stacked to provide passageways through the structure. The overlapping faces of the tiles are provided with aligned recesses or sockets. Keys slightly smaller than, but substantially conforming to the dimension and shape of, said sockets are positioned therein for tying the structure together.
PATENTEDUEBZBIQYI 3530.503
INVENTOR.
CARLISLE O. BYRD, JR.
ATTORNEY FIG. I
INTERLOCKING TILE STRUCTURE This invention relates to a heat exchange structure for heating and cooling gases. Hot and cold gases are alternately passed through the structure. Heat is transferred from the hot gases to the structure which retransfers the heat to the cold gases. There are many uses for this type of heat exchange structure. For example, in the production of oxygen or solid carbon dioxide, heat exchangers or regenerators are used to freeze out moisture. Another application of heat exchangers is to recover heat from process or combustion gases and utilize such heat to preheat combustion air. Still another use of such regenerators is for cracking hydrocarbons to olefins and acetylene.
There are any number of heat exchange structure designs. This invention relates to an improvement in heat exchange structures comprised of a plurality of grooved tiles known in the industry as Hasche tiles. These tiles are named after their inventor and are generally similar to those described in US. Pat. No. 2,622,864. Occasionally, after a heat exchange structure comprising a plurality of these tiles has been used for a period of time, the structure loosens to the point where tiles actually fall out. This appears to be due to shifting or so-called walking of the tiles which takes place as the structure expands and contracts with each heating and cooling cycle.
According to this invention, there is provided an interlocking heat exchange structure comprising a plurality of tiles which are stacked and tied together in a manner which prevents walking but does not cause the individual tiles to be subjected to strains that might cause their failure. The objects of this invention are achieved without resorting to a tongue-and-groove design. This is important because it is very essential that the tile be manufactured as flat as possible with parallel opposed faces. Occasionally, it is necessary to flatten the faces, for example by grinding, which would be all but impossible with tongues extending from the faces of the tile. Furthermore, since these tiles are manufactured of ceramic materials they tend to have the brittle character of such materials. Thus, annoying precautions must be taken when shipping tile having tongues since the tongues have a tendency to break off. Also, the tiles cannot be stacked face-to-face without the occurrence of stresses that often develop into cracks.
Further features and advantages of this invention will become apparent to one skilled in the art by a study of the following description made with reference to the drawings in which;
FIG. 1 is a pictorial view of a heat exchange structure embodying tile of the type with which the present invention is concerned; and
FIG. 2 is a pictorial view of four such tiles shown in the overlapping relationship they maintain within the heat exchange structure. The topmost tile is shown in broken away section to expose aligned sockets and a key associated therewith.
As shown in FIG. I, a heat exchange structure according to the present invention comprises a housing 3 which may be made of any suitable material. The housing is provided with a gas inlet 5 and an oppositely disposed gas outlet (not shown) and preferably has an insulating, refractory lining. Within the housing 3 are a plurality of rectangular, lamellar, refractory tiles 11.
As best shown in FIG. 2, each of these tiles has similar, flat front and back edges I5 and similar, flat side edges 17 and comprises substantially parallel, spaced, opposed faces on its top and bottom. Each of the faces comprises a plurality of lands 23 which are separated by substantially semicircular grooves 25, the grooves being substantially straight and substantially parallel and extending completely across the tile between the edges 15. The grooves 25 in one face are staggered with respect to the grooves in the opposed faces. At the side edges of each tile the upper face of the tile terminates in narrow lands 27 which are only half as wide as the lands 23 between the grooves 25 while the bottom or lower face terminates in quadrant-shaped grooves 29.
In the heat exchange structure, tiles 11 as described above are arranged edge to edge and face-to-face in the casing I3 to form flat, parallel, superposed courses in which the grooves in the faces of each tile in one course are aligned with the grooves in the adjacent faces of the contiguous tiles in the courses above and below to form passageways through said structure. The tiles in each course may be different in size from those in the adjacent coursesso that the joints between the tiles in adjacent courses are broken. It will be apparent that when two tiles Ill are laid side by side the two narrow lands 27 fit together to form a split land of the same width as the full width lands 23 and the adjacent quadrant-shaped grooves 29 cooperate to form a vertically split, substantially semicircular groove of the same size as the grooves 25.
The detent means provided for restraining superposed tiles from relative movement parallel to the upper or lower faces thereof and thus prevent walking" of the tiles under the influence of alternating heating and cooling cycles comprises a plurality of keys engaging in sockets formed in the lands 23. In pressing the tile II to shape a plurality of sockets 33 are molded in each of the lands 23 at spaced predetermined distances from the ends of the tile. Thus the superposed lands have mating sockets into some of which keys may be inserted while the tiles are being laid so as to interlock the several courses.
The sockets 33, and of course the keys engaging therein, may take various shapes. As preferred and shown in the drawing, each socket is generally hemispherical and the keys 35 shown in FIG. 2 are balls or rounded pellets but of somewhat smaller diameter than the recesses. Thus the keys fit loosely and provision is made for the change of size of the sockets and/or keys resulting from thermal expansion. It will be understood, however, that the sockets and from may have other shapes if desired. For example, the sockets may be hemicylindrical in shape and the cooperating keys may be shaped as small cylinders.
Preferably the keys used in carrying out the present invention are made of ceramic materials similar to or the same as that of the tiles. Thus a high alumina refractory material is usually satisfactory. In some instances, however, other materials such as other ceramic materials or a heat-resistant metal can be used. As pointed out above, provision must be made for changes of size resulting from heat expansion of the tile and keys in dimensioning the keys. Making them from similar ceramic material minimizes this difficulty. The keys may be formed to the desired size and shape by any suitable known fabrication procedure. Aside from clearance for heat expansion some extra clearance between keys and sockets may be desirable to permit slight shifting of tiles without placing undue strain on an individual tile.
In constructing a heat exchange structure according to the present invention a first course of tiles is laid in place. Then keys are placed in a desired number of sockets in the tiles so laid. As successive layers or courses of tiles are laid, keys are placed in the sockets before the next course is put down until a stack of tile of the desired size is obtained. It will be evident that there need not be a key in every socket. In general, two or three keys between each pair of overlapping tile are sufficient. It will be apparent that the keys help to align the tiles as they are laid so that the facing grooves form passageways. In the past, it was usually necessary to lay aligning rods in the grooves of one course to insure proper positioning of the next course. When structures according to this invention are built the keys alone may be used to perform this function. Having thus described the invention with the particularly required by the patent laws, what is desired protected by Letters Patent are as follows.
I Claim:
1. A heat exchange structure comprising a casing containing a plurality of lamellar refractory tiles, each of said tiles having two-spaced, substantially parallel, rectangular opposed faces; each of said faces comprising a plurality of lands, the lands being separated by grooves; said grooves being substantially straight and substantially parallel and extending completely across said tile with the grooves in one of said faces staggered with respect to the grooves in the other said face; said tiles being arranged edge-to-edge and face-to-face in said casing to form flat, parallel, superposed courses in which the joints between the tiles in adjacent courses are broken and the grooves in said faces of each tile are aligned with the grooves in the adjacent faces of the contiguous tiles above and below, whereby to form passageways through said structure, the lands of one tile contacting the lands of contiguous tiles so the lands in the bottom face of one tile fit flatly against the lands in the top face of another tile, sockets being provided in said lands, a socket in one land mating a socket in another land of a con-