CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application is based on and claims domestic priority benefits under 35 USC §1 19(e) from U.S. Provisional Patent Application Serial No. 62/138,615 filed on March 26, 2015, and may be deemed to be related to commonly owned copending U.S. Patent Application Serial Nos. 14/947,320 filed on November 20, 2015 and --/—,— filed concurrently herewith (Atty. Dkt. No. 6141 -52), the entire content of each prior filed application being expressly incorporated hereinto by reference.

FIELD

[0002] The embodiments disclosed herein relate generally to coke ovens, especially corbel structures associated with coke ovens. In preferred embodiments, the corbel structures disclosed herein are formed of an assembly of monolithic refractory blocks.

BACKGROUND

[0003] Coke ovens traditionally comprise massive refractory brick structures in which there are batteries of adjacent parallel walls

constructed from a large variety of differently shaped refractory bricks. The bricks must be able to withstand high temperatures and strong mechanical loading. At the same time, the interior of the walls contains flue ducts, burners, flue gas control passages and the like. The detailed design of the oven is usually quite complicated in order to obtain the necessary heat distribution within the oven and gas flows through the walls.

[0004] It follows from the above that coke ovens are relatively costly structures and any downtime for servicing and repairs can represent a significant economic loss for an operator. [0005] Further, the production of ceramic bricks from which the walls are made is relatively costly and there is accordingly a need to generally reduce the number of different types of bricks which are used in a wall. It is undesirable, however, to have a design concept which utilizes relatively large ceramic bricks in the construction. Excessively large bricks cannot be handled without the use of specialized mechanical lifting devices. Additionally, bricks having a dimension greater than 650 mm machine pressed to form a fused silica product are generally unavailable. Bricks greater than this size can be hand cast but these are much more expensive. Large bricks can be machine pressed from conventional silica, but conventional silica bricks would have a very serious

disadvantage in that a wall made therefrom would need a heat-up time which is many times greater than that for fused silica bricks.

[0006] U.S. Patent Nos. 6,066,236, 8,266,853 and 8,640,635 (the entire content of each such patent being expressly incorporated hereinto be reference) have proposed that relatively large-sized monolithic refractory blocks may be assembled to form the corbel structures of coke ovens. In general, the assembly of such large-sized monolithic refractory blocks enables the coke ovens to be constructed and/or repaired with much less production down time.

[0007] While such prior proposals for coke oven corbel structures are satisfactory for their intended purpose, continual improvements are sought. It is towards providing such improvements that the embodiments disclosed herein are directed.

SUMMARY

[0008] The coke oven corbel structures of the embodiments disclosed herein include an assembly of multiple stacked tiers of refractory blocks defining a plurality of substantially vertically oriented central flues and a plurality of diagonally oriented lateral flues. At least one tier of refractory blocks in the assembly includes an assembly of multiple stacked tiers of refractory blocks defining a plurality of

substantially vertically oriented central flues and a plurality of generally diagonally oriented lateral flues provided by an alternating plurality of saddle blocks and central diagonal flue blocks. The saddle blocks comprise a laterally opposed pair of upright columns which define therebetween a rectangular channel, and a substantially vertically oriented cylindrical flue extending from a bottom surface of the saddle blocks to the rectangular channel thereof. The central diagonal flue blocks comprise an arcuately concave flue channel defined between top and bottom surfaces thereof so that an upper opening to the flue channel at the top surface is inwardly offset relative to a lower opening thereof at the bottom surface.

[0009] According to some embodiments, the saddle blocks and the central diagonal flue blocks are generally trapezoidal having step surfaces on opposed lateral edges thereof. The saddle blocks may alternatively or additionally comprise a cylindrical boss which is received within a correspondingly configured cylindrical recess of another block in subjacent tier of the corbel structure. The central diagonal flue blocks may be alternately oppositely oriented in the at least one tier of refractory blocks so that the lower openings thereof are positioned on alternately opposite laterals sides of the corbel structure.

[0010] The at least one tier of refractory blocks may also comprise a series of substantially Z-shaped blocks having a central post section and oppositely oriented ledge sections at each end of the central post section. One of the ledge sections of the Z-shaped blocks may thus be received and supported by a respective one of the step surfaces of the saddle blocks and the central diagonal flue blocks.

[0011] At least one tier of refractory blocks may also comprise a series of substantially T-shaped blocks laterally adjacent to the series of Z-shaped blocks. If present, the T-shaped blocks include a central column and opposed outwardly projecting ledge sections at an upper end of the central column, wherein one of the outwardly projecting ledge sections of the T-shaped blocks is received and supported by a respective oppositely oriented ledge section of the Z-shaped blocks.

[0012] Certain embodiments will include at least one generally trapezoidal spacer block positioned adjacent one of the saddle blocks and central diagonal flue blocks in the at least one tier of blocks.

[0013] At least one of the saddle blocks in the tier of blocks may further comprise a pair of oppositely oriented arcuate lateral flues on respective lateral sides of the substantially vertically oriented cylindrical flue.

[0014] The rectangular channel defined by the saddle blocks may comprise a cylindrical recess at an upper end of the substantially oriented vertical flue. Alternatively or additionally, the bottom surface of the saddle blocks may include a cylindrical boss at a lower end of the substantially vertical cylindrical flue. The at least one tier of refractory blocks may also be provided with substantially rectangular flue blocks received within a respective one of the rectangular channels of the saddle blocks.

[0015] The assembly of multiple stacked tiers of refractory blocks according to some embodiments of the corbel structure may further comprise a second tier of refractory blocks subjacent to the at least one tier of refractory blocks which includes an alternating series of central flue blocks and diagonal flue blocks. The central flue blocks may thus define a substantially vertical flue section in fluid communication with the substantially vertically oriented cylindrical flue of the saddle blocks. The diagonal flue blocks may define a downwardly and outwardly inclined surface at one end thereof in fluid communication with the lower opening of the arcuately concave flue channel defined by a respective one of the central diagonal flue blocks in the at least one tier of refractory blocks. [0016] The central diagonal flue blocks of the at least one tier of refractory blocks may be alternately oppositely oriented so that the lower openings of the arcuately concave flues are positioned on alternately opposite laterals sides of the corbel structure. In such embodiments, the diagonal flue blocks of the second tier of refractory blocks may be alternately oppositely oriented so that the inclined surface at one end thereof is in fluid communication with a respective one of the arcuately concave flue channels of the central diagonal flue blocks of the at least one tier of refractory blocks.

[0017] Certain embodiments herein will include at least one additional tier comprised of a plurality of tongue-and-groove

interconnected refractory blocks. The plurality of interconnected refractory blocks of the at least one tier may comprise mutually

substantially orthogonal faces defining an edge and respectively including an elongate tongue protruding outwardly therefrom and an elongate groove recessed therein. The elongate tongue and groove include respective adjacent ends which co-terminate with one another at the edge defined by the mutually orthogonal faces of the refractory blocks.

[0018] The multiple stacked tiers of refractory blocks may optionally include a respective end block having a front face, wherein the front face includes a substantially vertically oriented tongue and a substantially vertically oriented groove parallel with the tongue, the tongue and groove of the front face being interconnected with a groove and tongue, respectively, of a substantially vertical face of an adjacent block in the tier.

[0019] These and other aspects and advantages of the present invention will become more clear after careful consideration is given to the following detailed description of the preferred exemplary embodiments thereof. BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS

[0020] The disclosed embodiments of the present invention will be better and more completely understood by referring to the following detailed description of exemplary non-limiting illustrative embodiments in conjunction with the drawings of which:

[0021] FIG. 1 is a perspective view showing an exemplary corbel structure in accordance with an embodiment of the present invention supported on a coke oven pier;

[0022] FIGS. 2 and 3 are top plan and front end elevational views, respectively, of the corbel structure shown in FIG. 1 ;

[0023] FIG. 4 is an enlarged perspective assembled view of the first tier of blocks forming the corbel structure shown in FIG. 1 ;

[0024] FIGS. 4A-1 through 4A-3 show an end block associated with the first tier of blocks forming the corbel structure, wherein FIG. 4A-1 is a perspective view thereof, FIG. 4A-2 is a top plan view thereof and FIG. 4A-3 is a front elevational view thereof;

[0025] FIGS. 4B-1 through 4B-3 show a first channel block associated with the first tier of blocks forming the corbel structure, wherein FIG. 4B-1 is a perspective view thereof, FIG. 4B-2 is a top plan view thereof and FIG. 4B-3 is an end elevational view thereof;

[0026] FIGS. 4C-1 through 4C-3 show a second channel block associated with the first tier of blocks forming the corbel structure, wherein FIG. 4C-1 is a perspective view thereof, FIG. 4C-2 is a top plan view thereof and FIG. 4C-3 is an end elevational view thereof;

[0027] FIG. 5 is an enlarged perspective assembled view of the second tier of blocks forming the corbel structure as viewed from above; [0028] FIG. 5A is an enlarged perspective assembled view of the second tier of blocks depicted in FIG. 5 as viewed from below;

[0029] FIGS. 5A-1 through 5A-5 show a central end block associated with the second tier of blocks forming the corbel structure, wherein FIG. 5A-1 is a perspective view thereof, FIG. 5A-2 is a bottom plan view thereof, FIG. 5A-3 is a side elevational view thereof, FIG. 5A-4 is a rear end elevational view thereof, and FIG. 5A-5 is a cross-sectional elevational view thereof as taken along line 5A-5 in FIG. 5A-1 ;

[0030] FIGS. 5B-1 through 5B-4 show a first lateral end block associated with the second tier of blocks forming the corbel structure, wherein FIG. 5B-1 is a perspective view thereof, FIG. 5B-2 is a top plan view thereof, FIG. 5B-3 is a front elevational view thereof, and FIG. 5B-4 is an end elevational view thereof;

[0031] FIGS. 5C-1 through 5C-4 show a second lateral end block associated with the second tier of blocks forming the corbel structure, wherein FIG. 5C-1 is a perspective view thereof, FIG. 5C-2 is a top plan view thereof, FIG. 5C-3 is a front elevational view thereof, and FIG. 5C-4 is an end elevational view thereof;

[0032] FIGS. 5D-1 through 5D-4 show a central flue block associated with the second tier of blocks forming the corbel structure, wherein FIG. 5D-1 is a perspective view thereof, FIG. 5D-2 is a top plan view thereof, FIG. 5D-3 is a bottom plan view thereof, and FIG. 5D-4 is an end elevational view thereof;

[0033] FIGS. 5E-1 through 5E-4 show a central spacer block associated with the second tier of blocks forming the corbel structure, wherein FIG. 5E-1 is a perspective view thereof, FIG. 5E-2 is a top plan view thereof, and FIG. 5E-3 is a bottom plan view thereof, and FIG. 5E-4 is an end elevational view thereof; [0034] FIGS. 5F-1 through 5F-4 show a first type of elongate key block associated with the second tier of blocks forming the corbel structure, wherein FIG. 5F-1 is a perspective view thereof, FIG. 5F-2 is a top plan view thereof, FIG. 5F-3 is a side elevational view thereof, and FIG. 5F-4 is a front elevational view thereof;

[0035] FIGS. 5G-1 through 5G-4 show a second type of elongate key block associated with the second tier of blocks forming the corbel structure, wherein FIG. 5G-1 is a perspective view thereof, FIG. 5G-2 is a top plan view thereof, FIG. 5G-3 is a rear end elevational view thereof, and FIG. 5F-4 is a front end elevational view thereof;

[0036] FIG. 6 is an enlarged perspective assembled view of the third tier of blocks forming the corbel structure;

[0037] FIGS. 6A-1 through 6A-5 show a central end block associated with the third tier of blocks forming the corbel structure, wherein FIG. 6A-1 is a perspective view thereof, FIG. 6A-2 is a top plan view thereof, FIG. 6A-3 is a bottom plan view thereof, FIG. 6A-4 is a front elevational view thereof, and FIG. 6A-5 is a side elevational view thereof;

[0038] FIGS. 6B-1 through 6B-4 show a lateral end block associated with the third tier of blocks forming the corbel structure, wherein FIG. 6B-1 is a perspective view thereof, FIG. 6B-2 is a top plan view thereof, FIG. 6B-3 is a bottom plan view thereof, FIG. 6B-4 is a side elevational view thereof and FIG. 6B-5 is an end elevational view thereof;

[0039] FIGS. 6C-1 through 6C-4 show a first type of central flue block providing both vertical and diagonally lateral flue sections associated with the third tier of blocks forming the corbel structure, wherein FIG. 6C-1 is a perspective view thereof, FIG. 6C-2 is a top plan view thereof, FIG. 6C-3 is a front elevational view thereof, FIG. 6C-4 is a latitudinal cross-sectional elevational view thereof taken along line 6C-4 in FIG. 6C-2;

[0040] FIGS. 6D-1 through 6D-3 show a diagonal flue block associated with the third tier of blocks forming the corbel structure, wherein FIG. 6D-1 is a perspective view thereof, FIG. 6D-2 is a top plan view thereof, and FIG. 6D-3 is an end elevational view thereof;

[0041] FIGS. 6E-1 through 6E-5 show a second type of central flue block associated with the third tier of blocks forming the corbel structure, wherein FIG. 6E-1 is a perspective view thereof, FIG. 6E-2 is a top plan view thereof, FIG. 6E-3 is a bottom plan view thereof, FIG. 6E-4 is cross- sectional view thereof as taken along line 6E-4 in FIG. 6E-2, and FIG. 6E- 5 is an end elevational view thereof;

[0042] FIGS. 6F-1 through 6F-3 show a spacer block associated with the third tier of blocks forming the corbel structure, wherein FIG. 6F-1 is a perspective view thereof, FIG. 6F-2 is a top plan view thereof and FIG. 6F-3 is a bottom plan view thereof;

[0043] FIG. 7 is an enlarged perspective assembled view of the fourth tier of blocks forming the corbel structure as viewed from above;

[0044] FIG. 7A is an enlarged perspective assembled view of the fourth tier of blocks depicted in FIG. 7 as viewed from below;

[0045] FIGS. 7A-1 through 7A-3 show an end block associated with the fourth tier of blocks forming the corbel structure, wherein FIG. 7A-1 is a perspective view thereof, FIG. 7A-2, is a top plan view thereof, and FIG. 7A-3 is a front elevational view thereof;

[0046] FIGS. 7B-1 through 7B-4 show a first type of saddle block associated with the fourth tier of blocks forming the corbel structure, wherein FIG. 7B-1 is a front perspective view thereof, FIG. 7B-2 is a rear perspective view thereof; FIG. 7B-3 is a top plan view thereof and FIG. 7B-4 is a cross-sectional view thereof as taken along line 7B-4 of FIG.7B-

3;

[0047] FIGS. 7C-1 through 7C-4 show a second type of saddle block associated with the fourth tier of blocks forming the corbel structure, wherein FIG. 7C-1 is a front perspective view thereof, FIG. 7C-2 is a top plan view thereof, FIG. 7C-3 is a front elevational view thereof and FIG. 7C-4 is a cross-sectional view thereof as taken along line 7C-4 of FIG.7C- 2;

[0048] FIGS. 7D-1 through 7D-4 show a central diagonal flue block associated with the fourth tier of blocks forming the corbel structure, wherein FIG. 7D-1 is a perspective view thereof, FIG. 7D-2 is a top plan view thereof, and FIG. 7D-3 is a front elevational view thereof, and FIG. 7D-4 is a cross-sectional elevational view thereof as taken along line 7D-4 in FIG. 7D-2;

[0049] FIGS. 7E-1 through 7E-3 show a central spacer flue block associated with the fourth tier of blocks forming the corbel structure, wherein FIG. 7E-1 is a perspective view thereof, FIG. 7E-2 is a top plan view thereof, and FIG. 7E-3 is a front elevational view thereof;

[0050] FIGS. 7F-1 through 7F-3 show an elongate upper edge block associated with the fourth tier of blocks forming the corbel structure, wherein FIG. 7F-1 is a perspective view thereof, FIG. 7F-2 is a top plan view thereof, FIG. 7F-3 is a side elevational view thereof, and FIG. 7F-4 is a front elevational view thereof;

[0051] FIGS. 7G-1 and 7G-2 depict a first type of central shelf block associated with the fourth tier of blocks forming the corbel structure, wherein FIG. 7G-1 is a perspective view thereof and FIG. 7G-2 is a front elevational view thereof; [0052] FIGS. 7H-1 and 7H-2 depict a second type of central shelf block associated with the fourth tier of blocks forming the corbel structure, wherein FIG. 7H-1 is a perspective view thereof and FIG. 7H-2 is a front elevational view thereof; and

[0053] FIGS. 71-1 through 7I-3 depict a lateral shelf block associated with the fourth tier of blocks forming the corbel structure, wherein FIG. 71-1 is a perspective view thereof, FIG. 7I-2 is a top plan view thereof, and FIG. 7I-3 is a front elevational view thereof.

DETAILED DESCRIPTION

[0054] Accompanying FIGS. 1 -3 shows an exemplary corbel structure 10 in accordance with an embodiment of the present invention supported on a pier P associated with a coke oven battery. In this regard, it will be understood that a conventional coke oven battery will include a number of spaced apart piers P, each supporting a corbel structure 10 and defining therebetween regenerator regions provided with checker bricks (not shown). The corbel structures 10 in turn support the refractory walls and floors of the individual coke ovens (not shown).

[0055] The corbel structure 10 is generally comprised of essentially four courses 100, 200, 300 and 400 assembled from especially configured refractory blocks (to be described in greater detail below) which are stacked one on top of another. The courses 100, 200, 300 and 400 collectively define central substantially vertically oriented flues 60 and lateral substantially diagonally oriented flues 72 which communicate with corresponding flues within the walls of the coke oven walls (not shown) to allow for the burning of air and gas therein and the transport of heated waste gas to and from the regenerator regions.

[0056] FIG. 4 is a perspective assembled view of the

interconnected refractory blocks forming the first tier 100 of the corbel structure, with FIGS. 4A-1 through 4C-3 showing respective views of the individual refractory blocks thereof. In this regard, it will be observed that the first tier 100 of blocks is formed of an assembly of an end block 102 and first and second channel blocks 104, 106, respectively, forming an elongate substantially horizontal channel 108 to allow gas to flow from one end of the corbel structure 10 to the opposite end thereof.

[0057] FIGS. 4A-1 through 4A-3 depict the end block 102 of the first tier 100. As shown, the end block 102 defines a substantially horizontal plateau surface 102a to allow a gas to enter into the channel 108 defined collectively by the assembled first and second channel blocks 104, 106, respectively. The end block 102 includes a latitudinally separated pair of raised profile sections 105, 107, respectively. The section 107 has a lesser dimension in the longitudinal direction of the block 102 as compared to the section 105 so as to establish a lateral inlet channel defined by the plateau surface 102a which fluid communicates with the longitudinal channel 108. Each of the sections 105, 107 includes a raised longitudinally oriented central ridge 105a, 107a positioned between a pair of longitudinally oriented U-shaped grooves 105b, 107b, respectively.

[0058] A representative one of the first channel blocks 104 is depicted in FIGS. 4B-1 through 4B-3. As is seen by comparing the front profiles of the elevational views of FIG. 4B-3 and FIG. 4A-3, the latter defines the same upper surface profile as the latter. Thus, the block 104 will include a central longitudinally oriented section of the channel 108 positioned between a pair of opposed longitudinally oriented raised profile sections 1 10, 1 12. Each of the sections 1 10, 1 12 includes a raised longitudinally oriented central ridge 1 10a, 1 12a positioned between a pair of longitudinally oriented U-shaped grooves 1 10b, 1 12b, respectively, which as noted above are longitudinally coincident with the ridges 105a, 107a and the grooves 105b, 107b, respectively. [0059] The second type of channel block 106 shown by FIG. 4C-1 through FIG. 4C-3 is substantially identical to the block 104 as describe previously with a principal exception being that the dimension as measured in the longitudinal direction of the first tier 100 of blocks is less as compared to the same dimension of the second type of channel block 104. Thus, the relative thickness of the block 106 is less as compared to the block 104 thereby enabling the blocks 104 and 106 to be assembled adjacently as may be needed to accommodate varying longitudinal dimensional requirements for the first tier 100 of blocks associated with the corbel structure 10. Thus, similar structural components of the block 106 have been identified with the same reference numeral as those employed for block 104 with an added prime (') designation.

[0060] FIGS. 5 and 5A show perspective assembled views from above and below, respectively, of the interconnected refractory blocks forming the second tier 200 of the blocks associated with the corbel structure 10, with FIGS. 5A-1 through 5G-4 showing respective views of the individual refractory blocks thereof. In this regard, the second tier 200 of blocks is provided by an end assembly which includes a central block 202 and lateral blocks 204, 206 and a series of central flue blocks 208 which in the embodiment shown are alternately disposed adjacent to central spacer blocks 210. Elongate interior key blocks 212, 214 are provided (see FIG. 5B) so as to positionally lock and support the central end block 202.

[0061] The central end block 202 is shown in greater detail by FIGS. 5A-1 through 5A-5. As shown the central end block 202 is generally a rectangular parallelepiped with a ledge projection 202a extending outwardly from an end thereof. The bottom surface of the central end block includes a pair of elongate tongues 202b which mate with corresponding grooves on a subjacent block (e.g., one of the interior key blocks 212, 214). A semi-cylindrical recess 202c is formed in the bottom surface of the block 202 and is open toward the rear end thereof.

[0062] A first lateral end block 204 associated with the second tier 200 of blocks forming the corbel structure 10 is shown in FIGS. 5B-1 through 5B-4. As shown, the block 204 is generally in the form two conjoined rectangular parallelepiped sections 204a, 204b with the section 204a being laterally off-set relative to section 204b so as to protrude laterally therefrom. The top and bottom surfaces are provided with an elongate groove 204c and tongue 204d to mate with a corresponding tongue and groove of a superjacent and subjacent block, respectively.

[0063] The second lateral end block 206 which is positioned on a side of the central block 202 opposite to the lateral end block 204 is depicted in FIGS. 5B-1 through 5B-4. As shown, the block 206 is provided with essentially a central square parallelepiped section 206a and a pair of parallelepiped sections 206b, 206c protruding outwardly therefrom at a forward and rearward end thereof. The section 206c is joined to the section 206a at an end thereof by a vertically oriented slanted surface 206d. The top surface of the section 206a is provided with a groove 206e while the forward end and bottom surface thereof are provided with coextensive tongues 206f, 206g, respectively.

[0064] FIGS. 5D-1 through 5D-4 show a central flue block 208 associated with the second tier 200 of blocks forming the corbel structure 10. As depicted in such drawings, the central flue block 208 is generally a rectangular parallelepiped shape provided with an upper raised platform section 208a defining a section of the substantially vertical flue 60. A cylindrical recess 208a1 is formed on the upper surface of the raised platform section so as to accommodate appropriately sized ceramic gas nozzles 220 (see FIG. 5). An elongate inverted U-shaped channel 208b is formed on the bottom side of the block 208. Each of the lateral side sections 208c, 208d of the block 208 includes a respective lateral inverted U-shaped channel 208c1 , 208d1 , respectively, between which the channel 208b is positioned. Elongate grooves 208e1 , 208f1 and 208e2, 208f2 on the top and bottom surfaces are paired with coextensive tongues 208g, 208h and grooves 208i, 208j on opposed front and rear surfaces of the sections 208c, 208d, respectively.

[0065] The central spacer block 210 depicted in FIGS. 5E-1 through 5E-4is substantially identical to the central flue block 208 but does not include the cylindrical section of flue 60 or the recess 208a1 . As such, the block 210 has a lesser thickness dimension (i.e., the dimension of the block 210 as measured in the longitudinal direction of the corbel structure 10). Corresponding structure in block 210 has therefore been identified by the same reference numeral with a prime (') designator.

[0066] A first type of key block 212 associated with the second tier 200 of the corbel structure 10 is depicted in FIGS. 5F-1 through 5F-4. As shown, the key block 212 is a generally elongate parallelepiped having a groove and tongue 212a, 212b on its top and bottom surfaces that are each coextensive with a tongue and groove 212c, 212d on its front and rear surfaces, respectively. The key block 212 may be provided in varying lengthwise dimensions so as to accommodate the particular design attributes of the corbel structure 10.

[0067] The second type of key block 214 is similar to block 212 in that a top and bottom grove and tongue 214a, 214b are provided on the top and bottom surfaces which are coextensive with a tongue 214c formed on a rear face thereof. Unlike block 212, however, the block 214 includes a planar beveled front face 214d.

[0068] FIG. 6 shows a perspective assembled view from above of the interconnected refractory blocks forming the third tier 300 of the blocks associated with the corbel structure 10, with FIGS. 6A-1 through 5F-3 showing respective views of the individual refractory blocks thereof. In this regard, the third tier 300 of blocks is provided by an end assembly which includes a central end block 302 and a pair of lateral end blocks 304. The third tier 300 is also comprised of a series of first and second central flue blocks 308, 312 and diagonal flue bocks 310 interposed therebetween in oppositely alternating orientations. A spacer block 314 may also be provided as needed in the corbel structure 10 design.

[0069] FIGS. 6A-1 through 6A-5 show the central end block 302 associated with the third tier 300 of blocks forming the corbel structure 10. The central end block 302 is a trapezoidal solid structure having opposed downwardly converging planar side surfaces 302a, 302b and opposed substantially vertical front and rear surfaces 302c, 302d, respectively. A raised central platform 302e is formed on the top surface thereof while an inverted U-shaped channel 302f is formed in the bottom surface thereof opposite the platform 302e. A trapezoidal channel 303a, 303b is formed in each of the side surfaces 302a, 302b.

[0070] As shown in FIGS. 6B-1 through 6B-4, the lateral end blocks 304, like the central end block 302, is a trapezoidal structure. However, the lateral end blocks 304 include opposed planar downwardly divergent side surfaces 304a, 304b having elongate trapezoidal bosses 305a, 305b which are received within the correspondingly configured channels 303a, 303b of the central end block 302. A series of cylindrical apertures 304-1 are formed in the block 304 between the substantially vertical front and rear faces 304c, 304d, respectively. The top and bottom surfaces 304e, 304f, respectively, are planar and substantially parallel to one another. A latitudinal heel 304g extends outwardly from the bottom surface 304f between the side surfaces 304a, 304b.

[0071] A first type of central flue block 308 providing both vertical and diagonally lateral flue sections 60, 72, respectively, associated with the third tier 300 of blocks forming the corbel structure 10 is depicted in accompanying FIGS. 6C-1 through 6C-4. As shown, the block 308 is a generally trapezoidal solid structure having opposed downwardly convergent planar side surfaces 308a, 308b, opposed vertically planar front and rear surfaces 308c, 308d and opposed horizontally planar top and bottom surfaces 308e, 308f, respectively. Each of the side surfaces 308a, 308b includes a lateral diagonal U-shaped channel 308a1 , 308b1 . The bottom surface 308f defines a central inverted U-shaped channel 308f1 . The upper surface 308e defines a central cylindrical recess 309a which communicates with a conical recess 309b defining the vertical flue section 60 (see FIG. 6C-4).

[0072] A diagonal flue block 310 associated with the third tier 300 of blocks forming the corbel structure 10 is depicted in FIGS. 6D-1 through 6D-3. As shown, the block 310 includes an upwardly and inwardly inclined surface 310a at one end and a downwardly and inwardly inclined surface 310b at the other end. The block 310 otherwise has substantially parallel vertically planar front and rear surfaces 310c, 31 Od and substantially parallel horizontally planar top and bottom surfaces 31 Oe, 31 Of, respectively. The upwardly and inwardly inclined surface 310 forms an acute interior angle with respect to the bottom surface 31 Of, whereas the downwardly and inwardly inclined surface forms an obtuse interior angle with respect to the bottom surface 31 Of.

[0073] The second type of central flue block 312 depicted in FIGS. 6E-1 through 6E-5 is substantially identical to the first type of central flue block 308 but does not include the lateral diagonal U-shaped channel 308a1 , 308b1 . As such, the block 312 has a lesser thickness dimension (i.e., the dimension of the block 312 as measured in the longitudinal direction of the corbel structure 10). Corresponding structure in block 312 to that shown in block 308 has therefore been identified by the same reference numeral with a prime (') designator.

[0074] Likewise, the spacer block 314 depicted in FIGS. 6F-1 through 6F-3 is substantially identical to the second type of central flue block 312 but does not include the cylindrical recess 309a' or the conical recess 309b'. As such, the block 314 has a lesser thickness dimension (i.e., the dimension of the block 314 as measured in the longitudinal direction of the corbel structure 10). Corresponding structure in block 314 to that shown in block 312 has therefore been identified by the same reference numeral with a double prime (") designator.

[0075] FIGS. 7 and 7A show perspective assembled views from above and below, respectively, of the interconnected refractory blocks forming the fourth tier 400 of the blocks associated with the corbel structure 10, with FIGS. 7A-1 through 7I-3 showing respective views of the individual refractory blocks thereof. In this regard, the fourth tier 400 of blocks is provided by a adjacently positioned series central end block 402, first and second types of saddle flue blocks 404, 406, respectively, central diagonal flue blocks 408, spacer blocks 410, elongate upper edge blocks 412, first and second types of central shelf blocks (a representative few of which are identified by reference numerals 414, 416, respectively), and lateral shelf blocks (a representative few of which re identified by reference numeral 418).

[0076] The end block 402 associated with the fourth tier 400 of blocks forming the corbel structure 10 is depicted in greater detail in FIGS. 7A-1 through 7A-3. As shown, the end block 402 is generally a

trapezoidal structure having upper and lower step surfaces 402a, 402b on each lateral side thereof. A generally rectangular boss 402c1 projects outwardly from the substantially horizontal front face 402c opposed to a substantially planar rear face 402d. The top and bottom faces 402e and 402f, respectively, are substantially planar rectangular surfaces.

[0077] FIGS. 7B-1 through 7B-4 depict the first type of saddle block 404 associated with the fourth tier 400 of blocks forming the corbel structure 10. As shown, the block 404, is generally a trapezoidal structure having upper and lower step surfaces 404a, 404b on each lateral side thereof, opposed front and rear substantially vertical planar surfaces 404c, 404d and opposed top and bottom substantially horizontal planar surfaces 404e, 404f, respectively. An open ended rectangular recess 405 is formed in the top and rear faces 404e and 404d, respectively, so as to receive a correspondingly configured flue block 407 (see FIG. 7). The bottom of each flue block 407 includes a cylindrical boss (not shown) which is received within a correspondingly configured cylindrical recess 405a communicating with a substantially vertically oriented cylindrical flue 405b of the block 404 (see FIG. 7B-4). As noted in the drawings, the flue blocks 407 may be of different vertical heights. The bottom surface 404f includes a cylindrical boss 405c which is received within the

correspondingly configured cylindrical recess 309a of the block 308 when stacked thereon (see FIGS. 6C-1 through 6C-4). An opposed pair of arcuately concave flue channels 404-1 , 404-2 are defined within the block 404 between the top and bottom surfaces 404e, 404f, respectively, so that the upper opening to each flue channel 404-1 , 404-2 is inwardly offset relative to the lower opening thereof.

[0078] The second type of saddle block 406 associated with the fourth tier 400 of blocks forming the corbel structure 10 is depicted in FIGS. 7C-1 through 7C-4. As shown, the block 406, like blocks 402 and 404, includes upper and lower step surfaces 406a, 406b on each lateral side thereof. The block 406 also includes a laterally opposed pair of upright columns 406-1 , 406-2 which define therebetween a rectangular channel 409 for receiving a correspondingly configured flue block 407. As noted previously, the bottom of each flue block 407 includes a cylindrical boss (not shown) which is received within a correspondingly configured cylindrical recess 409a communicating with a substantially vertically oriented cylindrical flue 409b of the block 406 (see FIG. 7C-4). The bottom surface 406f includes a cylindrical boss 409c which is received within the correspondingly configured cylindrical recess 309a' of the flue block 312 of the third tier 300 of blocks when stacked thereon (see FIGS. 6E-1 through 6E-5).

[0079] FIGS. 7D-1 through 7D-4 depict a central diagonal flue block 408 associated with the fourth tier 400 of blocks forming the corbel structure 10. As shown, the flue block 408, like the blocks 402, 404 and 406, is generally a trapezoidal structure having upper and lower step surfaces 408a, 408b on each lateral side thereof, opposed front and rear substantially vertical planar surfaces 408c, 408d and opposed top and bottom substantially horizontal planar surfaces 408e, 408f, respectively. An arcuately concave flue channel 408-1 is defined within the block 408 between the top and bottom surfaces 408e, 408f, respectively, so that the upper opening to the flue channel 408-1 is inwardly offset relative to the lower opening thereof.

[0080] A central spacer block 410 that may be employed in the fourth tier 400 of blocks forming the corbel structure 10 is depicted in FIGS. 7E-1 through 7E-3. As shown, the spacer block 410, like the blocks 402, 404, 406 and 408, is generally a trapezoidal structure having upper and lower step surfaces 410a, 410b on each lateral side thereof, opposed front and rear substantially vertical planar surfaces 410c, 41 Od and opposed top and bottom substantially horizontal planar surfaces 41 Oe, 41 Of, respectively.

[0081] An elongate upper edge block 412 associated with the fourth tier 400 of blocks forming the corbel structure 10 is shown in FIGS. 7F-1 through 7F-3. As shown the edge block 412 is structurally similar to the key block 212 described previously in connection with the second tier 200 of blocks. As shown, the edge block 412 is a generally elongate parallelepiped having a groove and tongue 412a, 412b on its top and bottom surfaces that are each coextensive with a tongue and groove 412c, 412d on its front and rear surfaces, respectively. The edge block 412 may be provided in varying lengthwise dimensions so as to

accommodate the particular design attributes of the corbel structure 10.

[0082] FIGS. 7G-1 and 7G-2 depict a first type of central shelf block 414 employed in the fourth tier 400 of the corbel structure 10. As shown, the block 414 is substantially a T-shaped structure having a central column section 414a and opposed outwardly projecting ledge sections 414b, 414c.

[0083] FIGS. 7H-1 and 7H-2 depict a second type of central shelf block 416 employed in the fourth tier 400 of the corbel structure 10. As shown, the block 416, like the block 414, is substantially a T-shaped structure having a central column section 416a and opposed outwardly projecting ledge sections 416b, 416c. In addition, the block 416 also includes a pair of downwardly projecting feet 416-1 , 416-2 which define therebetween an inverted U-shaped channel 416-3.

[0084] FIGS. 71-1 through 7I-3 depict a lateral shelf block 418 associated with the fourth tier 400 of blocks forming the corbel structure 10. As shown, the block 418 is substantially a Z-shaped structure having a central post section 418a and oppositely oriented ledge sections 418b, 418c at each end thereof. As is shown in FIGS. 7 and 7A, an oppositely oriented pair of the Z-shaped shelf blocks 418 is associated with one of the T-shaped shelf blocks 414 or 416 so that the outwardly projecting ledge sections 414b, 414c or 416b, 416c are received and supported by a ledge section 418c of a respective block 418. In addition, it will be observed from FIGS. 7 and 7A that the ledge sections 418b of the interior series of blocks 418 are received and supported by a respective lower step surface 402b, 404b, 406b, 408b and 410b of a respectively associated adjacent block 402, 404, 406, 408 and 410. The collective top surfaces of blocks 412, 414 and 418 therefore provide a coplanar support surface for supporting a row of generally rectangular edge blocks 420 (see FIGS. 7 and 7A). [0085] The various blocks as described above which comprise the corbel structure 10 are preferably provided with interlocking tongue and groove structures such as described in U.S. Provisional Patent Application Serial No. 62/082,922.

[0086] It will be understood that the description provided herein is presently considered to be the most practical and preferred embodiments of the invention. Thus, the invention is not to be limited to the disclosed embodiments, but on the contrary, is intended to cover various

modifications and equivalent arrangements included within the spirit and scope thereof.