Title:
Refractory block and refractory wall assembly
Kind Code:
A1


Abstract:
A refractory block for forming a wall structure comprising a body of cast refractory material. The body has a front face, a back face, a top face, a bottom face, and two opposing side faces. The body further has a projection formed on the top face and a recess formed in the bottom face, the projection being dimensioned to be received within the recess such that a projection on a block can be received in a recess on a block thereabove. A refractory anchor is embedded within the body. The anchor has a portion extending from the body through the back face.



Inventors:
Stephansky, John J. (Fair Oaks, PA, US)
Berry, John E. (Wexford, PA, US)
Application Number:
11/182085
Publication Date:
11/02/2006
Filing Date:
07/15/2005
Assignee:
Harbison-Walker Refractories Company
Primary Class:
International Classes:
E04H14/00; E04F19/00
View Patent Images:
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Primary Examiner:
RINEHART, KENNETH
Attorney, Agent or Firm:
KUSNER & JAFFE (Mayfield Heights, OH, US)
Claims:
Having described the invention, the following is claimed:

1. A refractory block for forming a wall structure, comprising: a body of cast refractory material, said body having a front face, a back face, a top face, a bottom face, and two opposing side faces, said body further having a projection formed on said top face and a recess formed in said bottom face, said projection dimensioned to be received within said recess, such that a projection on a block can be received in a recess on a block thereabove; and a refractory anchor embedded within said body, said anchor having a portion extending from said body through said back face.

2. A refractory block as defined in claim 1, wherein said anchor extends through said block and has an end that projects through, and is coplanar with, said front face of said block.

3. A refractory block as defined in claim 1, wherein said second end of said insert is flush with said front face of said block.

4. A refractory block as defined in claim 1, wherein said block has a cube-like configuration.

5. A refractory block as defined in claim 1, wherein said projection on said upper face is a rail-like shape that extends along said upper face of said block.

6. A refractory block as defined in claim 5, wherein said recess has a channel-like shape that extends along the lower face of said block.

7. A refractory block as defined in claim 1, wherein said extending portion of said anchor includes surface means for attaching said anchor to a shell of a furnace.

8. A refractory block as defined in claim 7, wherein said surface means is an opening formed in said extending portion of said anchor.

9. A refractory block as defined in claim 8, wherein said opening is a bore extending through said extending portion of said anchor.

10. A refractory block as defined in claim 9, wherein said bore is cylindrical in shape and extends parallel to said back face.

11. A refractory block as defined in claim 1, wherein each of said faces is flat and is perpendicular to contiguous faces.

12. A refractory block as defined in claim 1, wherein said block is formed of about 45% to about 80% of coarse grained high alumina castable or a fused zirconia-mullite castable.

13. A refractory block as defined in claim 1, further comprising a lifting device embedded in said block.

14. A refractory block as defined in claim 13, wherein said lifting device is accessible through said top face.

15. A refractory block as defined in claim 14, wherein said lifting device is an internal threaded sleeve embedded in said block, one end of said sleeve being accessible through said top face.

16. A refractory block as defined in claim 1, wherein said anchor is wedge-shaped.

17. A refractory block as defined in claim 16, wherein said anchor is an isopressed refractory.

18. A furnace wall structure, comprised of: a metallic wall panel; a refractory wall parallel to and spaced apart from a metallic panel comprised of a plurality of stacked refractory blocks, each of said blocks comprised of: a refractory body having a refractory anchor embedded therein, said anchor having a portion extending from said refractory block; said extending portion having an opening therein; a plurality of bracket elements attached to said wall panel, said bracket elements disposed between said metallic wall panel and said refractory wall and each having a receiving opening; and a fastener having a first portion dimensioned to be received in said receiving opening in said bracket and a second portion dimensioned to be received in said opening in said anchor, said fastener attaching said refractory blocks to said metallic panel.

19. A furnace wall structure as defined in claim 18, wherein each of said refractory blocks forming said refractory wall is attached to said metallic wall panel by a fastener.

20. A furnace wall structure as defined in claim 18, wherein said brackets are generally U-shaped and have spaced-apart leg portions, the ends of said leg portions being attached to said metallic wall panel.

21. A furnace wall structure as defined in claim 20, wherein said brackets are pieces of metallic structural channels and are welded to said metallic wall panel.

22. A furnace wall structure as defined in claim 20, wherein said receiving opening is defining between the legs of said U-shaped bracket.

23. A furnace wall structure as defined in claim 22, wherein said receiving opening is vertically oriented.

24. A furnace wall structure as defined in claim 18, wherein said refractory blocks forming said refractory wall are stacked in a staggered pattern.

25. A furnace wall structure as defined in claim 18, further comprising a refractory material disposed within the space between said refractory wall and said metallic wall panel.

26. A furnace wall structure as defined in claim 18, wherein said metallic wall panel is flat and is vertically oriented.

27. A furnace wall structure as defined in claim 18, wherein said fastener is a generally U-shaped rod having spaced-apart leg portions, said leg portions being received in said receiving opening in said bracket and said opening in said fastener.

28. A furnace wall structure as defined in claim 18, wherein each face of said refractory blocks is flat and is disposed at right angles to contiguous faces of said block.

29. A furnace wall structure as defined in claim 18, wherein said refractory block includes a projection formed on a top face of said body and a recess formed on a bottom face of said body, said projection dimensioned to be received within said recess.

30. A furnace wall structure as defined in claim 29, wherein said projection on said upper face is a rail-like shape that extends along said upper face of said block.

31. A refractory block as defined in claim 29, wherein said recess has a channel-like shape that extends along the lower face of said block.

Description:

FIELD OF THE INVENTION

The present invention relates generally to the refractory arts, more particularly to a refractory block and refractory wall assembly.

BACKGROUND OF THE INVENTION

A clinker cooler is a structure designed to cool hot clinker that exits a furnace, such as a rotary kiln. Such coolers typically allow the clinker to cascade down a sloping path over grates through which cooling air is passed.

The cooler structure is basically a metallic panel having an inner refractory block lining. Refractory blocks are stacked one on another to form a refractory wall that is spaced apart from the metallic panel. The refractory blocks that form the refractory lining are generally referred to as “cooler blocks,” and have heretofore been generally rectangular in shape having flat, outer surfaces. The blocks are formed from a cast refractory material having a metallic anchor, typically in the form of a U-shaped clip, cast within the block. A metallic, threaded rod is attached to the clip, typically by welding, and extends from one face of the block. The rod is dimensioned to extend through a hole in the metallic panel of the cooler structure. The threaded rod is attached to the metallic panel by conventional nut fasteners.

FIG. 12 shows a conventional cooler block as heretofore described, and FIG. 13 shows the cooler block attached to the outer metallic panel of the cooler structure. A refractory material (not shown in FIG. 13) would normally be inserted in the space or gap defined between the cooler block wall and the metallic panel of the cooler structure.

A problem with cooler blocks of the type heretofore described is that the metal clip that is embedded within the block, and the metallic rod that is connected thereto, act as heat sinks. Because of the high thermal conductivity of the metal clip and rod, heat within the block is quickly absorbed by the metal clip and is conducted directly to the metal rod. At times, the heat in the metal rod can cause its deterioration and failure over time. In addition, the metal rod conducts heat to the metallic panel of the cooler structure thereby eroding the strength of the metallic panel and causing buckling and distortion.

Another problem with the foregoing design is that it requires that holes be drilled into the metallic panel of the cooler structure, which reduces the overall structural integrity of the metallic panel. This together with the aforementioned heating of the panel can cause the buckling and distortion of the shell panel.

Another problem associated with cooler blocks known heretofore is the assembly and disassembly of such structure. As will be appreciated, aligning the metallic rod with the hole in the outer shell is not an easy task considering the weight of such a block can exceed 170 lbs. Still further, securing the locking nuts of each block is both tedious and time consuming.

The present invention overcomes these and other problems and provides a wall structure for a clinker cooler, and a cooler block for forming the same, which wall structure is easier to assemble and disassemble and does not require basic penetration of the metallic panel of the cooler structure. Further, a cooler block according to the present invention reduces the transfer of heat from the cooler block to the shell of the cooler structure.

SUMMARY OF THE INVENTION

In accordance with a preferred embodiment of the present invention, there is provided a refractory block for forming a wall structure comprising a body of cast refractory material. The body has a front face, a back face, a top face, a bottom face, and two opposing side faces. The body further has a projection formed on the top face and a recess formed in the bottom face, the projection being dimensioned to be received within the recess such that a projection on a block can be received in a recess on a block thereabove. A refractory anchor is embedded within the body. The anchor has a portion extending from the body through the back face.

In accordance with another embodiment of the present invention, there is provided a furnace wall structure comprised of a metallic wall panel and a refractory wall that is parallel to and spaced apart from the metallic panel. The refractory wall is comprised of a plurality of stacked refractory blocks. Each of the blocks is comprised of a refractory body having a refractory anchor embedded therein. The anchor has a portion extending from the refractory block; the extending portion has an opening therein. A plurality of bracket elements is attached to the wall panel. The bracket elements are disposed between the metallic wall panel and the refractory wall and each has a receiving opening. A fastener is provided having a first portion dimensioned to be received in the receiving opening in the bracket and a second portion dimensioned to be received in the opening in the anchor. The fastener attaches the refractory blocks to the metallic panel.

An advantage of the present invention is an improved wall structure for a clinker cooler.

Another advantage of the present invention is a wall structure as defined above that is easier to assemble than wall structures known heretofore.

Another advantage of the present invention is a wall structure as defined above that can accommodate for variations or waviness in the outer, metallic shell of the cooler structure.

A still further advantage of the present invention is a wall structure as defined above that reduces heat transfer from the cooler blocks to the metallic panel.

A still further advantage of the present invention is a wall structure as defined above that does not require threaded fasteners to attach the cooler block to the metallic panel of the cooler structure.

Another advantage of the present invention is a wall structure as defined above that is formed of interlocking cooler blocks.

Another advantage of the present invention is a cooler block having recesses and projections on the outer surface thereof for locking vertically adjacent cooler blocks.

A still further advantage of the present invention is a cooler block that can be cured at a higher temperature.

These and other advantages will become apparent from the following description of a preferred embodiment taken together with the accompanying drawings and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention may take physical form in certain parts and arrangement of parts, a preferred embodiment of which will be described in detail in the specification and illustrated in the accompanying drawings which form a part hereof, and wherein:

FIG. 1 is a perspective view of a partial wall structure for a clinker cooler illustrating a preferred embodiment of the present invention;

FIG. 2 is a front view of the wall structure shown in FIG. 1;

FIG. 3 is a sectional view taken along lines 3-3 of FIG. 2;

FIG. 4 is a sectional view taken along lines 4-4 of FIG. 2;

FIG. 5 is a perspective view of a cooler block, illustrating a preferred embodiment of the present invention, showing such cooler block together with mounting hardware used for mounting the cooler block to a metallic panel of a cooler structure;

FIG. 6 is a partially sectioned, elevational view of the cooler block shown in FIG. 5;

FIG. 7 is a sectional view taken along lines 7-7 of FIG. 6;

FIG. 8 is a sectional view taken along lines 8-8 of FIG. 6;

FIG. 9 is a perspective view of a cooler block, illustrating another embodiment of the present invention;

FIG. 10 is a partially sectioned, elevational view of the cooler block shown in FIG. 9;

FIG. 11 is a partially sectioned, top plan view of the cooler block shown in FIG. 9;

FIG. 12 is a perspective view of a cooler block known heretofore; and

FIG. 13 is a top sectional view of the cooler block shown in FIG. 12 showing such block attached to the metallic panel of a cooler structure.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT

Referring now to the drawings wherein the showings are for the purpose of illustrating a preferred embodiment of the invention only, and not for the purpose of limiting same, FIG. 1 is a perspective view of a portion of a partially assembled furnace wall structure 10, illustrating a preferred embodiment of the present invention. Furnace wall structure 10 depicted in the drawings shows a refractory wall structure for use in a “clinker cooler” that cools hot clinker as it exits a furnace, such as a rotary kiln (not shown).

Furnace wall structure 10 is comprised of a refractory wall 20 and a metallic panel 100 that form the outer shell of the cooler structure. Refractory wall 20 is formed from refractory blocks 30, 70. In the embodiment shown, refractory wall 20 is comprised of two different refractory blocks, as shall be described in greater detail below.

Refractory wall 20 is spaced from metallic panel 100 to define a gap or space “X” therebetween, best seen in FIG. 4. Refractory wall 20 rests upon a generally planar, refractory floor 14 that is formed within the cooler shell that is defined by metallic panel 100.

Referring now to FIGS. 5-8, refractory block 30 is best seen. Refractory block 30 is a body of cast refractory material. The refractory material is preferably comprised of about 45% to about 80% of coarse grained high alumina castable or a fused zirconia-mullite castable. Refractory materials sold by Harbison-Walker Refractories Company under the trade names VERSAFLOW® 45 C ADTECH, VERSAFLOW® 55 AR C ADTECH, VERSAFLOW® 70 C ADTECH, VERSAFLOW® 80 C ADTECH and by North American Refractories Co. under the trade name THOR AZSP find advantageous application in forming refractory blocks 30, 70. Refractory block 30 has a front face 32, a back face 33, a top face 34, a bottom face 35 and two opposing side faces 36, 37. In the embodiment shown, refractory block 30 has a generally cube-like configuration, wherein each face 32-37 is perpendicular to an adjacent face. It is contemplated that refractory block 30 need not be an exact cube, i.e., need not have identical dimensions along each face. In other words, the height, width and depth of refractory block 30 may not be equal.

A projection 42 extends upwardly from top face 34 of refractory block 30. In the embodiment shown, projection 42 is in the shape of an elongated rail that extends across top face 34 of refractory block 30 from side face 36 to side face 37. Rail-like projection 42 extends generally parallel to front face 32 and back face 33 of refractory block 30. A recess 44 is formed on the opposing face of refractory block 30, i.e., in bottom face 35. Recess 44 is dimensioned to matingly receive projection 42 on top face 34 of refractory block 30, as heretofore described. In the embodiment shown, recess 44 is in a shape of a channel that extends along bottom face 35 of refractory block 30 from side face 36 to side face 37. Channel-shaped recess 44 is parallel to front face 32 and back face 33, and is disposed to receive a projection 42 on a like refractory block 30 disposed below, as shall be described in greater detail below.

A refractory anchor 52 is embedded within the body of refractory block 30. A portion 52a of anchor 52 extends from refractory block 30 through back face 33 thereof. In the embodiment shown, anchor 52 has an end 52b that extends to front face 32 of refractory block 30, as best seen in FIG. 6. End 52b of anchor 52 is dimensioned and positioned to be coplanar, i.e., flush, with front face 32 of refractory block 30. In the embodiment shown, anchor 52 has a slight wedge shape, as best seen in FIG. 7, and includes a plurality of protrusions 52c and recesses 52d formed along the surface thereof.

Surface means 54 are formed on extending portion 52a of anchor 52. In the embodiment shown, surface means 54 is a vertically-oriented opening extending through extending portion 52a of anchor 52. Opening 54 in anchor 52 is preferably cylindrical in shape, and includes chamfered ends 56, as best seen in FIG. 6. In a preferred embodiment, anchor 52 is a pre-formed, power-pressed shape, formed by conventional hydraulic or mechanical means. The body of refractory block 30 is cast around anchor 52 in a conventionally known casting process to embed anchor 52 within refractory block 30.

A lifting device 62 is also embedded within refractory block 30. In the embodiment shown, lifting device 62 is comprised of a pipe coupling 64 that is disposed within the body of refractory block 30. One end of coupling 64 extends to the surface of top face 34 of refractory block 30. A clip 66 is welded to coupling 64 to help lock coupling 64 within refractory block 30. Coupling 64 has internal threads 64a dimensioned to receive a conventionally known lifting eyebolt 68, shown in phantom in FIG. 6.

Referring now to FIGS. 9-11, refractory block 70 is best seen. Refractory block 70 is similar to refractory block 30. Refractory block 70 includes a front face 72, a back face 73, a top face 74, a bottom face 75 and two opposing side faces 76, 77. Refractory block 70 includes a rail-like projection 82 along top face 74 thereof, and a mating recess 84 along bottom face 75 thereof. Refractory block 70 also includes an anchor 92 having an extending portion 92a, an end portion 92b that is flush with front face 72 and protrusions 92c and recesses 92d. Opening 94 is formed in extending portion 92a. Refractory block 70 also includes a lifting device 62 embedded therein similar to that previously described. The basic difference between refractory block 70 and refractory block 30 is that refractory block 70 is thinner than refractory block 30, i.e., the dimension between front face 72 and back face 73 of refractory block 70 is less than the dimension from front face 32 to back face 33 of refractory block 30.

Referring now to refractory wall structure 10, refractory block 30 and refractory block 70 are used to form a vertical, refractory wall 20. Refractory wall 20 is comprised of a plurality of refractory blocks 30, 70 that are stacked one on another. Refractory wall 20 is spaced a predetermined distance “X” from metallic panel 100.

Refractory wall 20 is connected to metallic panel 100 by a connection system 110 comprising mounting brackets 122 and connectors 132. In the embodiment shown, mounting brackets 122 are generally C-shaped elements having a body portion 122a and two, spaced-apart leg portions 122b. Leg portions 122b of mounting brackets 122 are attached to metallic panel 100 such that body portion 122a of bracket 122 is spaced from metallic panel 100. An upwardly facing opening 124 (best seen in FIG. 3) is defined between mounting brackets 122 and metallic panel 100. Opening 124 is generally rectangular in shape. In a preferred embodiment, mounting bracket 122 is formed from a section of a conventional C-channel or similarly bent plate, and leg portions 122b of each mounting bracket 122 are welded to metallic panel 100.

As best seen in FIG. 1, mounting brackets 122 are mounted to metallic panel 100, and arranged in vertically spaced-apart, horizontal rows 126. The vertical spacing between rows 126 is established such that each mounting bracket 122 is in horizontal alignment with extending portions 52a, 92a of refractory blocks 30, 70 when refractory blocks 30, 70 are stacked to form wall structure 20, as best seen in FIG. 4.

Connectors 132 are provided to connect refractory blocks 30, 70 forming refractory wall 20 to metallic panel 100. Connectors 132 are generally U-shaped elements having parallel end portions 132a. Each end portion 132a is dimensioned to be received in opening 124 defined by mounting brackets 122 and metallic panel 100, and in openings 54, 94 in extension portions 52a, 92a of anchors 52, 92. In the embodiment shown, each connector 132 is a cylindrical rod that has been bent or otherwise formed, into a U-shape, as best seen in FIG. 5.

Referring now to the use and operation of refractory blocks 30, 70 and the formation of refractory wall 20, mounting brackets 122 are first attached to metallic panel 100 of the clinker shell. As indicated above, mounting brackets 122 are aligned and vertically spaced in horizontal rows 126 that are generally parallel to refractory floor 14. As seen in FIG. 1, mounting brackets 122 in adjacent, horizontal rows 126 are preferably staggered from mounting brackets 122 above and below to facilitate staggered stacking of refractory blocks 30, 70 in a staggered arrangement. With mounting brackets 122 attached to metallic panel 100, a first lower course 142 of refractory block 30 is set in place a predetermined distance “X” from metallic panel 100. A refractory mortar 152 is preferably placed below and between each refractory block 30. In view of the weight of each refractory block 30, lifting eyebolt 68 is inserted into lifting device 62 embedded within each refractory block 30. Lifting eyebolt 68 is preferably used in conjunction with a crane (not shown), to move and position each refractory block 30 in place to form a first course 142 of refractory blocks 30. Each block 30 in first course 142 is positioned such that extending portion of refractory anchor 52 is adjacent to mounting bracket 122. A connector 132 is attached to mounting block 30 and metallic panel 100 by inserting one end of connector 132 in opening 124 defined by mounting bracket 122 and another end portion 132a in opening 54 formed in extending portion 52a of anchor 52 in refractory block 30, as illustrated in FIG. 4. Each refractory block 30 is preferably attached to metallic panel 100 by inserting connector 132 between mounting bracket 122 and extending portion 52a of anchor 52. Once all of connectors 132 have been inserted for first course 142 of refractory blocks 30, a second course 144 of refractory blocks 30 is then set upon first course 142 of refractory blocks 30. As indicated above, mounting brackets 122 in the second row are preferably offset from mounting brackets 122 in the first row, such that refractory blocks 30, when aligned with an associated mounting bracket 122, rest upon two refractory blocks 30 in first course 142. In other words, refractory blocks 30 in second course 144 are staggered and offset, such that vertical joint lines between adjacent refractory blocks do not align. Refractory mortar 152 is preferably applied to top face 34 of first course 142 of refractory blocks 30 prior to the laying of second course 144 of refractory blocks 30. As illustrated in FIGS. 1 and 4, rail-like projection 42 on top face 34 of refractory blocks 30 forming first course 142 are received in recesses 44 in bottom face 35 of refractory blocks 30 forming second course 144. In this respect, rail-like projections 42 and elongated recesses 44 in respective refractory blocks 30, allow for lateral positioning of upper refractory blocks 30 on two refractory blocks 30 therebelow. Again, lifting device 62 embedded within each refractory block 30, together with lifting eye bolt 68 and an overhead lifting device (not shown), are preferably used to set refractory blocks 30 in second course 144. Once second course 144 of refractory blocks 30 is in place, refractory blocks 30 are attached to metallic panel 100 by inserting connectors 132 in extending portion 52a of anchors 52 in refractory blocks 30 and into openings 124 defined between mounting brackets 122 and metallic panel 100. In a similar manner, successive courses 146, 148 of refractory blocks 70 may be stacked one upon another. In FIG. 1, first and second courses 142, 144 of refractory blocks 30 are shown. Courses 146, 148 are comprised of refractory blocks 70. As best seen in FIG. 4, projections 42, 82 and recesses 44, 84 on refractory blocks 30 and 70 are such that back faces 33 of refractory blocks 30 and back faces 73 of refractory blocks 70 align when refractory blocks 70 are stacked on refractory blocks 30.

By stacking one course of refractory blocks 30, 70 upon another, entire refractory wall 20 may be formed. A lightweight refractory material 162 is preferably inserted in space “X” defined between refractory wall 20 and metallic panel 100, as illustrated in FIG. 4.

The present invention thus provides unique refractory blocks 30, 70 that lend themselves to quick and easy assembly and disassembly of refractory wall 20. Refractory blocks 30, 70 from front faces 32, 72 to back faces 33, 73 are comprised of refractory material 162, thereby eliminating a metal heat sink within refractory blocks 30, 70, and reducing heat transfer from refractory wall 20 to metallic panel 100. Any heat transferred from front faces 32, 72 to back faces 33, 73 of refractory blocks 30, 70 is also partially dissipated by refractory material 162 in space “X,” and by anchors 52, 92 embedded in refractory material 162 of refractory blocks 30, 70. As a result, connectors 132 are exposed to less heat and are less likely to conduct heat to metallic panel 100. As will be appreciated, rectangular openings 124 defined between mounting brackets 122 and metallic panel 100 allow for partial misalignment of refractory blocks 30, 70 relative to mounting bracket 122, and likewise can accommodate deformations in metallic panel 100, as illustrated in FIG. 3. In this respect, a shorter connector 132 can be used where major deformation exists in metallic panel 100. Moreover, rectangular openings 124 defined between mounting brackets 122 and metallic panel 100 allow connectors 132 to be canted to one side and still attach anchors 52, 92 in refractory blocks 30, 70 to metallic panel 100. The foregoing furnace wall structure 10 provides a refractory wall 20 for metallic panel 100 wherein refractory wall 20 has lateral support through its connection to metallic panel 100.

Another advantage of the present invention results from the use of ceramic anchors 52, 92, in place of the metal clips and rods in refractory blocks 30, 70. The use of the ceramic anchors allows the blocks to be cured at a much higher temperature than could be used if metallic clips and rods were used in the refractory block. Curing at higher temperatures reduces the likelihood of moisture being trapped and retained in refractory blocks 30, 70, thereby providing stronger, more durable, refractory blocks 30, 70 having longer use life.

The foregoing description is a specific embodiment of the present invention. It should be appreciated that this embodiment is described for purposes of illustration only, and that numerous alterations and modifications may be practiced by those skilled in the art without departing from the spirit and scope of the invention. It is intended that all such modifications and alterations be included insofar as they come within the scope of the invention as claimed or the equivalents thereof.