Abstract:
A tile that has a channel that is sized and shaped to accommodate a bolt with a washer, and that extends from one side of the tile to a location near the center of the tile. The tile can be mounted solely with the bolts and washers, or with other support structures.

Description:
FIELD OF THE INVENTION  
       [0001]     This invention relates to a refractory tile for a wall, and to a method and apparatus for mounting such a tile.  
       BACKGROUND OF THE INVENTION  
       [0002]     In some incinerators, boiler tubes are used to carry feedwater to produce energy from the heat of the incinerator. The heat turns the water in the tubes to steam, which is directed to a turbine for generating power. To protect the tubes from the high temperatures and corrosive atmosphere, the walls and boiler tubes can be covered with protective tiles, which can be made of silicon carbide (SiC).  
       SUMMARY OF THE INVENTION  
       [0003]     Embodiments of the present invention include a tile that has a channel that is sized and shaped to accommodate a bolt with a washer, and that extends from one side of the tile to a location inside the perimeter of the tile, e.g., near the center of the tile. The tile can be mounted solely with the bolts and washers, or with other support structures. The tile can be made of any suitable material, including ceramic, such as SiC. Other embodiments include a tile system where each of a number of tiles in a square, with at least two tiles to a side, are substantially identical and each is supported on the wall by just one or more bolts and washers. Other embodiments will be evident from the following description, drawings, and claims. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0004]      FIG. 1  is a partial cross-sectional, partial plan view of a tile mounted against a wall with boiler tubes.  
         [0005]      FIGS. 2-4  are elevational, top, and bottom views of the tile shown in  FIG. 1 .  
         [0006]      FIGS. 5-7  are cross-sectional views of the tile shown in  FIG. 2 .  
         [0007]      FIG. 8  is a side view showing a lap joint.  
         [0008]      FIG. 9  is an elevational view of an array of tiles. 
     
    
     DETAILED DESCRIPTION  
       [0009]     Referring to  FIG. 1 , a refractory tile  10  is shown with an inner side mounted to a wall  12  that includes boiler tubes  14   a - 14   c.  The tubes are preferably mounted with a vertical orientation, and are spaced apart in the wall to define regions  16   a,    16   b  between the tubes. While three tubes are shown, and three tubes correspond to the width of a tile, the tile could cover one or more tubes. There could be many more than three tubes in total, and the tiles could be arranged in a two-dimensional array. While the terms vertical and horizontal are used here to describe movement with respect to a vertical wall, these terms are meant to be non-limiting and used for reference as relative terms. The tile can be made of silicon carbide or any other suitable material.  
         [0010]     Extending away from wall  12  at regions  16   a  and  16   b  are bolts  18   a  and  18   b  with washers  20   a  and  20   b.  While referred to here as washers, these components can have a variety of configurations, including an internal screw thread or no internal thread. The bolts can have threads or ridges or be smooth, and can have circular or other cross-sections. What is desirable, however, is for the combination of the bolt and the washer to have some mating connection, which can be just frictional, such that the washer can be moved relative to the bolt with some application of force or by turning, but such that the connection is preferably not too loose, such that the tile would fall off the bolts by moving in a direction perpendicular to the wall.  
         [0011]     Bolts  18   a  and  18   b  have a first diameter, and washers  20   a  and  20   b  have a second diameter greater than the first diameter. As used here, the term diameter is used broadly to refer to a width or diagonal if the bolt and washer do not have a circular outer diameter. Bolts  18   a  and  18   b  extend through outer channel regions  22   a  and  22   b,  which have a width that is greater than the first diameter but less than the second diameter at this location. The tile also has inner channel regions  24   a  and  24   b  that have a width that is wider than the second diameter. This means that once the tile is mounted on the wall with the bolt and washer in this location, the tile will not come off when moved in a direction perpendicular to the wall.  
         [0012]     The inner side of the tile can have curves that conform to the shape of the tubes, although the tile could have a flat inner side or some other configuration. The outer side  26  of the tile faces the incinerator and is substantially planar with no openings or channels, although it could have configurations. A mortar could be used on the wall with the tiles mounted up against the mortar. The tiles are each preferably spaced from the wall when mounted by a sufficient distance to allow a material, such as a silicon carbide castable to be poured behind the tiles. This castable hardens in a manner similar to a cement, but is in a pourable form to fill gaps better than a mortar.  
         [0013]     Referring to  FIG. 2 , tile  10  is shown as a generally rectangular tile with a height greater than its width, although it could have other orientations, such as be square, or have a greater width than height, or even have other configurations. Different sizes and shapes of tile could be used and combined to cover the wall. Tile  10  has vertical channels  30  and  32 .  FIGS. 2-7  show one embodiment of the arrangement of channels.  
         [0014]     Referring also to  FIG. 5 , channel  30  (or  32 ) has an outer channel portion  42  with a width greater than that of a bolt and less than that of a washer, and an inner channel portion  44  with a width greater than the diameter of the washer to prevent the tile from being moved in a direction perpendicular to and away from the wall when the washer and bolt are in this part of the channel.  
         [0015]     Referring also to  FIG. 6 , in another region of the channel, the tile has an opening  38  that is wider than the diameter of the washer, and thus allows the tile to be moved in a direction perpendicular to the wall, toward and way from the wall, when the washer and bolt are in this region.  
         [0016]     Referring to  FIG. 7 , in regions  34  and  36  ( FIG. 2 ) of the tile, the channel is effectively closed off by having a solid portion  46  in place of an outer channel portion, thereby leaving the inner portion  44  of the channel. This region of the tile prevents movement of the tile in a direction parallel to the wall in at least one direction vertically because portion  46  blocks movement of the tile relative to the bolt and allows the tile to hang on the bolt.  
         [0017]     As indicated by  FIGS. 2, 5 ,  6 , and  7 , the tile is mounted to the wall by aligning regions  38  and  40  with the bolts and washers on the wall and moving the tile in a direction generally perpendicular to the wall so that the bolt and washer extend into region  38  of the tile. The tile can then be moved downwardly relative to the wall until the bolts are at approximately locations  50  and  52  where the tile thus hangs on the wall. The space provided by the channel above regions  34  and  36  and portion  44  of the channel as shown in  FIG. 7  allows a tool to be inserted in the channel from the top of the tile to extend downwardly to move the washer to a desired location along the bolt. This movement can be provided with a manually operated or power tool.  
         [0018]     Referring to  FIGS. 3, 4 , and  8 , the bottom and top sides of the tiles are preferably designed to have a lap joint, such that the furnace side of the tile has a step down at the lower side of the tile, and the boiler side of the tile has a step up at the top as shown in  FIG. 8 . The steps are a little less than one-half the thickness of the tile to allow them to mate with each other. The lateral sides are shown as being planar, but they could have other configurations, such as a Z-shaped joint to help prevent gas from passing from one side to the other.  
         [0019]     Referring to  FIG. 9 , the tiles can be mounted on the wall with no additional brackets or other supporting mechanical mechanisms (although there could be mortar or other bonding material between the tiles and the wall, and expansion material between adjacent tiles). While other supports can be provided, such as additional brackets, the tile can be fully supported to the wall with substantial downward vertical movement and horizontal movement restricted solely with the one or more bolts and washers. In this particular embodiment, the tile has two and only two bolts and washers per tile. Because the tile only requires the bolts and washers to support the tile, each of the tiles  60 ,  62 ,  64 , and  66  in a two-dimensional array of at least two in the horizontal direction and two in the vertical direction can be substantially identical and can avoid the need of additional brackets or supports. While shown as an array with two tiles to a side, the array could be two by three, three by three, three by four, or any higher numbers.  
         [0020]     The system described here thus has each tile individually supported in the horizontal and vertical directions relative to a horizontal wall. The tiles can preferably be mounted so that there is a gap in both in the horizontal and vertical directions to adjacent tiles to allow an expansion material to be provided between each of the tiles in both the horizontal and vertical directions. In systems that use different types of tiles, such as support tiles and other tiles that are not individually supported but that use support tiles for their support, the tiles abut one another and would typically not have the expansion material in the vertical direction between every tile.  
         [0021]     By using one type of tile, the process can be simplified. In addition, with a limited number of bolts per tile, such as two as described here, the amount of bolts on the wall can be reduced.  
         [0022]     Having described certain embodiments, it should be apparent that other modifications can be made without departing from the scope of the inventions as defined by the appended claims. For example, while this description of the tile has been for use with an incinerator, the tile and mounting method can be used in any high temperature and/or corrosive environment, such as a furnace or a gasification system. While certain dimensions have been cited for an exemplary embodiment, other dimensions can be used for these components. For example, the tile can be in the range of 1 inch to 24 inches square.