JP3689000B2 - Fireproof tiled construction for boiler tube / heat exchanger protection - Google Patents

Abstract

A refractory tile system (60) includes a barrier layer coating (61) applied to the wall (16) of a boiler. Refractory tiles (66) are then fastened to the tu be wall (16) utilizing a floating attachment mechanism (68) to provide a relatively high degree of freedom of movement relative to the tube wall to accommodate micro-scale bowing of the tile generated by the relatively large temperature gradient and mean temperature typically experienced by such tile s. Each tile (66) is also isolated from adjacent tiles by providing a predetermined gap (70) therebetween of sufficient size to effectively preven t macro-scale bowing. Moreover, a compressible fibrous mortar is disposed in t he gap between each adjacent tile to prevent contaminants from passing therethrough.

Description

[0001]
1. Field of Invention
The present invention is directed to a refractory tube block that protects metal flow wall tubes from hot and highly corrosive furnace gases while maintaining good thermal conductivity.
[0002]
2. Background information
Refractory tiles have long been used to protect boiler walls in waste incinerators and other application heat exchangers. The main function of this tile is to make the steel alloy boiler wall, typically comprising a water flow tube and a membrane or web (belt plate) disposed therebetween, acid, associated with temperature, erosion, and boiler action. It was to protect against corrosion due to the action of steam. These conditions are generated by the combustion process that takes place inside the boiler. For example, municipal solid waste (MSW) facilities incinerate litter and waste in furnaces at temperatures up to about 1400 ° C. In order to regenerate valuable energy generated in these MSW facilities, water is passed through a metal wall tube adjacent to the furnace and converted to steam by this high temperature. The steam generated in the tube assembly is then used to power a turbine driven generator. However, the MSW facility also produces a gas product that, when in contact with a metal wall, chemically corrodes this wall. The purpose of the refractory tile was to prevent direct corrosion of the wall by the gas product and the tube was still fully heated to efficiently generate water vapor. The primary purpose of this tile is therefore to increase the durability of the tube wall.
[0003]
Refractory tiles for boiler tube protection have traditionally been made from materials such as silicon carbide (SiC). These tiles are typically provided with a substantially planar surface with a back surface formed in a size and shape that matches the outer shape of the tube wall. Such tiles are generally variations of one of the three structures: bolted tiles, glued tiles as disclosed in U.S. Pat. No. 4,768,447 to Loumegua, and Aiken et al. US Pat. No. 5,243,801 of the US Patent No. 5,243,801 and one of the modified glazed tiles known as grooved or T-grooved tiles as disclosed in WO 97/095757 to Zampel Advanced Reflexory Technology Company It has been configured as one modification. U.S. Pat. No. 4,768,447, U.S. Pat. No. 5,243,801 and WO 97/09577 are fully incorporated herein by reference.
[0004]
As shown in FIGS. 1 and 2, the bolted tile 10 is generally provided with a square or rectangular surface 12 adapted to be arranged towards the interior of the boiler. One hole penetrates the thickness of the tile approximately at the center of the surface 12. Countersunk portion 34 is typically present within hole or hole 30 and serves as a seat for nut 28. In a typical mounting structure, a stud (plant bolt) or threaded bolt 24 is welded to the membrane portion 16 between the two tubes 18 of the boiler wall 62. The formed back surface 14 of the tile 10 includes an accurate portion 20 that is sized and shaped to fit and closely contact the contour of the tube wall 19.
[0005]
The tiles are mounted by passing the studs through the holes and fixing the mounting tiles in place with washers 28 and nuts 26 threaded into the studs. A cap (not shown) is then typically mortared over the hole in place to minimize the amount of gas that can flow to the back of the tile through the gap between the standard holes. . A layer of mortar (not shown) is typically applied between the tile and the wall 62 and between adjacent tiles to help fix the tile in place and gas between the tiles and / or the backside. A rigid structure is formed which acts to substantially prevent the flow of water.
[0006]
The advantage of using a bolted tile structure is that this tile is relatively easy to install and can be mounted on virtually any surface of the boiler, including vertical overhanging surfaces.
[0007]
The disadvantages of such bolted tiles are related to tile defects. These tiles typically have a useful life of 2 to 4 years due to the deterioration of the stud function. When the stud deteriorates, the tile will fall off the wall and the boiler tube will be exposed to the incinerator atmosphere. The cause of stud deterioration was previously thought to be due to high temperature acid corrosion. In particular, it was thought that acid would penetrate the tiles through the stud holes and attack the studs. This corrosion was considered severe for the stud due to its high working temperature (considered 1000 ° C. or higher). In addition, tile cracks were a normal phenomenon and were thought to occur due to excessive stress applied to the studs.
[0008]
One attempt to solve the shortcomings associated with bolted tile construction has included the use of glued tiles. As shown in FIGS. 3 and 4, the glued tile 45 typically uses anchors / hooks or short studs 37 to glue the tile to the membrane of the boiler wall 62, and gravity is used to bring the tile in close contact with the boiler wall 62. To maintain good heat conduction. The tile 45 is a variation of a bolted tile in that one or more holes 30 'protrude from the tile back surface 14' toward the hot surface but do not completely penetrate the hot surface. This provides a close surface to the tile and theoretically improves resistance to acid corrosion. A layer of mortar (not shown) is typically attached between the tile 45 and the boiler wall 62 and between adjacent tiles to form a rigid, substantially gas and ash impermeable structure.
[0009]
This variation of the tiled construction uses the tile 45 in conjunction with an air blow-through device. In this modification, the mortar is not attached to the back side of the tile, leaving a gap between the tile and the boiler wall. Air flow is supplied through this gap to help minimize wall acid corrosion.
[0010]
The advantage of glued tiles is that they are generally relatively easy to install and replace. A disadvantage of this tiled tile structure is that the tile cannot be mounted on a non-vertical wall because it tends to fall away from its fixed part. It is also known that these tiles are lifted away from their fixed part during operation due to thermal expansion and the like. Furthermore, the air blow-off device described above disadvantageously increases the cost of the tile structure over structures using mortar. Heat transfer between the tile and the wall is also disadvantageously reduced due to the insulating (ie, relatively low thermal conductivity) properties of the air layer.
[0011]
Referring to FIG. 5, a modified glazing tile 50 has been developed in an attempt to eliminate the drawbacks associated with glazing tiles that become detached from their anchors or hooks. Examples of this modified structure are commonly known as mushroom bolts, tube weld fin anchors, and T-groove tiles. These tiles 50 are typically composites of bolted tiles and glued tiles that combine the closely tiled surface 12 'with anchors 52 having a substantially T-shape to effectively capture the tiles. To be mounted on vertical and overhanging surfaces.
[0012]
These tiles 50 are generally fitted with a layer of mortar between the tile and the boiler wall and between adjacent tiles. The purpose of the mortar is to help secure these tiles by providing a rigid attachment, and to provide a barrier that resists ash and corrosive gases from penetrating between and behind the tiles.
[0013]
The advantage of these modified tiles 50 is that they can be mounted on any apparent boiler surface. The disadvantage of tile 50 is that it is difficult to manufacture because it incorporates a dead-end (ie, discontinuous) groove 54 that projects laterally into the tile from its edge. Also, these tiles are physically weak due to the complexity of this dead-end groove (growing groove) 54. Furthermore, individual tiles generally cannot be replaced without removing the middle row tiles.
[0014]
Other methods intended to eliminate the disadvantages of the above structure include the use of a glued tile 45 in combination with an elastic material 48 mounted between opposed recesses or grooves 49 shown in FIGS. Yes. This method tends to facilitate the installation and replacement of tiles as compared to a tiled structure using conventional hard mortar. While this method works satisfactorily in certain applications, the elastic material 48 can disadvantageously resist little to the flow of corrosive gases, so that it can be used in particularly corrosive environments such as those found in MSW boilers. It becomes undesirable.
[0015]
Furthermore, many of the methods described above use a fiber compressible material or mortar over the life of the tile to act as an expansion joint. For example, this material is used every 7 to 15 tiles in a manner well known to those skilled in the art of brickwork (i.e., as commonly used in the construction of concrete walkways, etc.). These joints, however, disadvantageously cause acid and other corrosive materials to pass and corrode the underlying boiler wall. Furthermore, the useful life of a tiled structure with such an expansion joint has not been shown to be much longer than a similar tile structure without such an expansion joint.
[0016]
Therefore, there is a need for an improved refractory tiled structure that eliminates the disadvantages associated with the prior art.
[0017]
Overview
An important aspect of the present invention is the recognition of problems corresponding to many of the prior art structural defects. These defects include individual tile bends ("minor scale" bends used here) and many tile accumulated bends (as used herein "interrelated" or "large scale") as shown in FIG. It was recognized that this was caused by “bending”. Referring to FIG. 9, a micro-scale bend generates a force F that is transmitted to an adjacent tile via a rigid mortar (not shown), thus producing a large-scale bend effect. This large bend applies sufficient tensile stress to the stud to cause degradation. In this regard, it has previously been thought that the large dimensional instability of the tile is mainly limited to the thermal expansion that occurs due to exposure to elevated boiler temperatures. Furthermore, bending was thought to be limited to individual tiles.
[0018]
In contrast, the present invention provides a thermal gradient caused by individual tiles during operation of the boiler (ie, the difference between the temperature of the hot surface 112 'and the back surface 114' shown in FIG. 7, for example) previously predicted. And is based on the recognition that it has had a greater impact on tile dimensional instability than previously discussed thermal expansion. And the bending caused by the thermal gradient transfers the stress through a rigid mortar placed between adjacent tiles, effectively changing the effect of individual tile bending as a function of the square of the length of the tiled structure. It was understood that This phenomenon is expressed by the following equation.
δ = αL² ΔT / (8t)
Where δ = cumulative deflection, α = thermal expansion coefficient, L is the length of the tile row, ΔT is the difference between the temperatures of the opposing faces of the tile, and t is the thickness of the tile.
[0019]
It has also been found that oxidation of hot surfaces on the tile that occurs over a long period of time forms "thermal spots" that further intensify the temperature gradient across the tile and further increase the micro-scale bending effect. In this regard, it has been found that large-scale bends initiate a self-permanent cycle that acts to accelerate oxidation and thus accelerate tile degradation. For example, the optimum working temperature of the hot surface of the SiC tile can be about 500 to 600 ° C. It has been found that oxidation at this temperature is minimal and does not substantially affect the lifetime of the tile. However, it has been found that the oxidation proceeds rapidly when the hot surface reaches about 750 ° C. or exceeds this temperature and continues to accelerate rapidly as the temperature is further increased. Accordingly, it was an aspect of the present invention to recognize that large bends act to separate the tile from the boiler wall and generally form an air gap that reduces heat transfer from the back of the tile to the wall. This reduction in heat transfer actually increases the temperature at the hot surface beyond the preferred operating temperature range. This large bend ultimately has the effect of raising the temperature of the hot surface to an oxidation promoting temperature of 750 ° C. or higher. This oxidation also increases the temperature gradient which will further exacerbate large-scale bends as described above, thereby creating a self-permanent deleterious cycle.
[0020]
Thus, since prior art tile structures have been developed to minimize acid penetration (ie, laying and modifying tiles 45 and 50 with hole growth), this tile structure does not confirm the above bending conditions. Nor is it intended. These conventional structures still use stiff mortar around the tiles, thereby causing large-scale bends.
[0021]
Similarly, some of the above-described expansion joint defects that would produce any substantial benefit may be recognized as partly due to this defect and an attempt to compensate for the overall bending phenomenon and relatively good thermal expansion effects. Understood. This defect is not only due to relatively small or rare expansion joints (ie, only used once every 7 to 15 tiles), but also usually disposed within at least a portion of the expansion joint. Also shown by frequent use of mortar.
[0022]
The first step in developing the present invention was to assess the cause of cracking of the tile in operation, including the completion of a first limited element model (FEM) of a regular 18 cm x 18 cm bolted tile. This analysis indicated the presence of tile stress due to thermal gradients. It was also shown that individual tiles bend as a function of thermal gradient. The initial result of this analysis was to increase the thickness of the tile and increase the strength of the tile.
[0023]
After this initial analysis was completed, a second limited element model was completed to predict a thermal diagram across the tile and along the length of the stud. With a predicted incinerator operating temperature of 1370 ° C., this model predicted that the stud would operate at temperatures above 800 ° C., the highest operating temperature for most stainless steels.
[0024]
Deteriorated studs were recovered from the incinerator. Stud analysis showed that these studs were stretched about 6 mm before they deteriorated. This indicated that the stud was placed under a tensile load and therefore was not degraded by acid corrosion alone but rather by stress-corrosion. Therefore, it was decided to investigate the cause of stud stress.
[0025]
Furthermore, it was observed that there was a blistering portion of the tile during the recovery of the deteriorated stud. These blisters were approximately 10 tiles × 10 tiles in this area and were displaced into the boiler.
[0026]
A third limited element model was started to study the phenomenon of tile bending and tensile stress. As previously mentioned, the first FEM showed that individual tile bends or large bends were caused by thermal gradients. However, this bend was not large enough (0.3 mm) to cause the 6 mm deformation seen in the stud.
[0027]
In the third FEM, 7 × 7 rows of tiles were modeled and the mortar was expected to act as a stiff material. The results of this analysis showed the overall effect in tiles that generate large bends exceeding 25 mm. In addition, stress analysis showed that the entire (large scale) bend applied sufficient tensile force on the stud to stretch the stud to the point of failure.
[0028]
To ensure a limited element model, a test panel fitted with tiles was installed in the incinerator. Data collected from the test panel showed that the tiles bent extensively during operation, and the bend magnitude was about 4 mm after one year of use. An estimate of the bending speed indicates that the tile will be displaced by 8 mm in about 2.5 years from the start of the test (displacement deemed necessary for stud deterioration). This corresponds well with observations of previous service life from bolted tiles.
[0029]
  Therefore, the present inventionFirstAccording to the aspect, used for boiler wallIsResistanceFireIlluminated structureA plurality of tiles having a floating mounting mechanism engageable with the wall, and a corrosion barrier disposed between the plurality of tiles and the wall, wherein the floating mounting mechanism includes a plurality of tiles on the wall. Keeping them in a distantly movable relationship with each other, the tiles form gaps between adjacent tiles that are sufficient to allow dimensional changes of the tiles to occur while exposed to the boiler operating temperature A refractory tiled structure characterized in that the corrosion barrier is a coating applied to the wall and formed from a coating that adheres to the wall but does not adhere to the plurality of tiles Will be provided.
[0030]
  The second of the present inventionAccording to the aspectUsed for boiler wallsIsResistanceFireIlluminated structureA plurality of tiles disposed on the wall and movably spaced apart from each other, and a corrosion barrier disposed between the plurality of tiles and the wall and substantially preventing corrosion of the wall, The tile has a size and shape that forms a gap between adjacent tiles that is sufficient to substantially prevent large-scale bending of the plurality of tiles while exposed to the operating temperature of the boiler; Is provided with a refractory tiled structure characterized in that it is formed from a coating applied to a wall that adheres to the wall but does not adhere to a plurality of tiles..
[0031]
  The third of the present inventionAccording to the aspect, How to improve the useful life of boiler wall(A) providing a plurality of tiles having a floating attachment mechanism engageable with a wall, wherein the tiles are held in spaced relation to each other on the wall by the floating attachment mechanism; (B) the size and shape of the tiles so that a sufficient gap is formed between adjacent tiles to allow for dimensional changes of the tiles that occur during exposure to the operating temperature of the boiler; And (c) forming a coating that adheres to the wall but does not adhere to the plurality of tiles by coating on the wall, and disposing a corrosion barrier made of the coating on the wall; Engaging the floating mounting mechanism with the wall such that the tiles are superimposed on the wall and the corrosion barrier is disposed between the plurality of tiles and the wall..
[0032]
These and other features and advantages of the present invention will become more readily apparent upon reading the following detailed description of the various forms of the present invention in conjunction with the accompanying drawings.
[0033]
Detailed Description of the Preferred Embodiment
Exemplary embodiments of the present invention are described in detail below with reference to the figures described in the accompanying drawings. For the sake of clarity, the same features shown in the accompanying drawings are indicated with the same reference numerals, and similar features shown in other embodiments in the drawings are indicated with the same reference numerals.
[0034]
As used in this disclosure, the term “axial” when used in connection with the elements described herein refers to the direction relative to this element, which is shown in FIGS. The central axis of the tube 18 when placed in engagement with the tube 18a(Ie, FIG. 7). The term “transverse direction” refers to a direction substantially perpendicular to the axial direction.
[0035]
Referring now to FIG. 6, in one embodiment of the present invention, the refractory tiled structure 60 is a barrier layer applied to an incinerator or heat exchanger boiler wall 62 (ie, membrane 16 and tube wall 19). A coating 61 is included. This barrier layer 61 is adapted to provide acid and salt corrosion resistance at the normal operating temperature of the boiler. An example of such a coating is a phosphate bonded SiC barrier layer such as PC-1022® available from the Norton company of Worcester, Massachusetts. Advantageously, this material provides relatively good corrosion resistance and thermal conductivity. The refractory tile 66 is then fastened to the tube wall 62 in a superimposed relationship with the tube wall 62 using a floating mounting mechanism 68. Tile 66 is known to those skilled in the art, such as silicon carbide (SiC) or other ceramic materials, such as silicon carbide (SiC) or other ceramic materials that can withstand the temperatures experienced inside MSW incinerators / heat exchangers and other boilers (as high as about 1400 ° C.). Consists of any suitable refractory material.
[0036]
The floating attachment mechanism 68 provides the tile 66 with a relatively high degree of freedom of movement relative to the tube wall 62 so that it can accommodate the small bends of the tile. As mentioned above, small bends have been found to be caused by the relatively large temperature gradients (typically about 200 to 600 ° C. or higher) experienced by these tiles. Furthermore, as mentioned above, this temperature gradient is particularly inconsistent with the dimensional instability of the tile, which is substantially greater than the elevated temperature itself, especially in light of the overall effect that the bending increases as the square of the length of the row of tiles. Is known to have the effect of Each tile 66 is effectively isolated from adjacent tiles by providing a predetermined gap 70 large enough to effectively prevent large bends between adjacent tiles that are known to occur due to the overall configuration. Is done. As shown in FIG. 9, this overall phenomenon is the pressure or force applied to each other by the tiles through a hard mortar (not shown) when bent to a small scale.FCaused by.
[0037]
Referring again to FIG. 6, the gap 70 is preferably formed by a peripheral edge 72 that is sized and shaped to form a spaced and interengaged joint between adjacent tiles 66. This interengaging structure advantageously serves to provide a closed row between the tiles and prevents ash or other contaminants from penetrating through this gap 70 during boiler operation. Furthermore, a compressible fiber mortar (not shown) is placed in the gaps or passages 70 between each adjacent tile to further prevent ash or other contaminants from penetrating. An example of such a suitable compressible fiber mortar is known as Topcoat 2600® available from Uniflux Company of Niagara Falls, New York. When this compressible fiber mortar is used, the gap 70 is sized in combination with the known compressibility of the selected special compressible mortar, thereby maximizing the transfer of force between the tiles. When it is arranged in the state of a small-scale bend, the size is kept low enough to substantially prevent the occurrence of a large-scale bend. For example, a tile having a rectangular surface 112 ′ formed substantially as shown in FIG. 7 and extending about 30 cm × 20 cm has a gap 70 ′ extending at least about 6 mm from an adjacent tile.
[0038]
In the illustrated embodiment, the floating attachment mechanism 68 includes a plurality of flexible arms 76 having a convex termination 78 adapted to engage a similarly sized recess 80 disposed in the tile 66. A rail 74 is included. The arm 76 is thus biased into releasable engagement with the tile 66 to facilitate its installation and removal. Furthermore, the elasticity of the arm 76 causes the tile 66 to move or “float” relative to the wall 62 in response to a change in the size of the tile 66 caused by the thermal gradient and the increased average temperature. It acts to fasten. In this regard, the floating mounting mechanism 68 moves the tile 66 with respect to the wall 62 with at least three degrees of freedom (ie, three mutually perpendicular axes X, Y, Z shown). Furthermore, in addition to translational movement along the X, Y, and Z lines, the tiles can rotate around the tube 18 and / or bend toward or away from the tube 18. Rail 74, including arm 76 and convex end 78, is preferably constructed from a flexible, corrosion resistant material such as stainless steel.
[0039]
Also, as shown, the surface 112 of the tile 66 has a geometric shape that substantially matches the contour of the wall 62 and has a relatively uniform thickness on the tile.tTo be able to give.
[0040]
  Referring to FIG. 7, another embodiment of the present invention is shown as a tiled structure 60 '. This embodiment is substantially similar to the tiled structure 60 shown in FIG.TanSurface 112 'and other floatsMountingMechanism 68'And are used. As shown, thisFloating mounting mechanism68 'uses about 50% fewer arms 76', but in many respects,Floating mounting mechanismSimilar to 68.
[0041]
  floatingMountingMechanism 68,68'EmbodimentExplainedHowever, for those skilled in the art, the tiles expand on a small scale without causing a large-scale bending action as described above.OrSongOrVirtually any attachment mechanism capable of securing the tile to the boiler wall 62 so that it can be used without departing from the spirit and scope of the present invention.IsUnderstoodLike. In this regard, for example,Adequate clearance is installedmechanismAnd between the tilesAndExcessive dimensional change aboveNaInstall force or stressMechanismIn addition to adjacent tilesWithoutAs it happensOn the assumption that, Flexible arm 76,76 'HuhTheA rigid mounting mechanismCan be used.
[0042]
Examples of such other structures are made of stainless steel or the like and can be inserted into a substantially large hole 84 (shown in phantom) disposed within the tile and substantially parallel to the tile surface 112. Installation of one or more pins 82 (indicated by phantom lines) extending to Pin 82 is also secured to wall 62 in a conventional manner known to those skilled in the art (not shown). In this manner, the tile is secured to the wall 62 with sufficient clearance to effectively “float” with respect to the wall as described above.
[0043]
  Figure10And figure11, yet another embodiment of the present invention is shown as a tiled structure 60 ". This tiled structure 60" is illustrated in FIG.And figureIs substantially similar to the tiled structures 60 and 60 'shown in FIG.MountingMechanism 68 "is used.Floating mounting mechanism68 "is substantially" C "shaped so that the arm 76" engages the semi-cylindrical groove or recess 80 "of the tile 66" as shown, but in many respects FIG. ofFloating mounting mechanism68 '.
[0044]
Referring to Fig. 11, the groove 80 "of the tile 66" includes an upper groove 81 and a lower groove 83 extending axially inward from the upper and lower edges 116 and 118 of the tile 66 ", respectively. Preferably the axial distance d of the lower groove 83₂ Larger axial distance d₁ Only extends from the upper edge 116 to facilitate attachment of the tile 66 "as described below. Also, as shown, the upper and lower surfaces 116 and 118 are at the intersection of the grooves 81 and 83. Chamfered at an angle α of about 30 to 60 degrees to further facilitate the mounting of tile 66 ″ as described below. In the preferred embodiment, the angle α is about 45 degrees as shown.
[0045]
Referring now to FIGS. 12-15, a method of attaching a tile 66 ″ is shown. Referring to FIG. 12, the tile 66 ″ is substantially between the upper surface 116 of the tile and the upper and lower arms 76 ″. It is mounted by positioning it in a substantially axial alignment with this, by positioning a portion of the upper surface 116 in face-to-face engagement with the tube 18 as shown. 13. Referring to Figure 13, the surface 116 of the tile 66 "is an arrow.aIs moved axially upward as indicated by and the lower surface 118 is shown by an arrowbAs shown, the tube 18 is rotated closer. This action serves to cause the upper groove 81 (FIG. 11) to slide into receiving engagement with a set of (ie, uppermost) arms 76 "as shown. This movement causes the tile to move to the lower arm 76. The "pass through tile 66" continues until it can move in substantially parallel alignment with the tube 18 as shown in FIG. 14. The tile is then adjacent to the previously mounted tile 66 ". In the axial direction (iecIs translated and engaged so as to be received within the lower groove 83 (FIG. 11). This translational movement preferably continues until the lower arm 76 "engages the proximal end 120 (Fig. 11) of the groove 83. At this point, the adjacent tile 66" has its desired spacing as shown in FIG. The arrangement is interengaged and the installation is complete. Another tile 66 "(not shown) is then attached in a similar manner.
[0046]
The following illustrative examples are intended to illustrate certain aspects of the present invention. These examples are not to be construed as limiting.
[0047]
Example
Example 1-Comparison
  FIG.And figureA series of ordinary bolted tiles of the general type shown in 2 were installed in the furnace in the pattern shown in FIG. On tiles displayed in A, B, C and DRespectivelyLVDT (A linear variable-displacement transducer) was attached to measure the displacement of these tiles away from the tube wall during normal furnace operation. As shown, tiles B and D were placed in a tile row section containing ordinary flexible mortar [Topcoat 2600® above] between adjacent tiles. Referring to FIG. 17, LVDT'sThe output shows that the mounted tiles were displaced almost simultaneously with each other, providing evidence that a large bend occurred. (The difference in displacement shown in the chart is clearly the LVD inside the tile.T'sThis was due to the change in position. ) LVD placed on tile BT isNote that it does not work well and is therefore not shown in FIG.
[0048]
Example 2
An array of tiles of the present invention was attached to a boiler for testing. These tiles are constructed and attached to the boiler in a manner substantially as shown in FIG. 7 and described above for that figure, with the barrier material between the boiler wall and the tile and the Topcoat 2600® between the adjacent tiles. Included use. Selected tiles designated as A, B, C, D, E, and G were mounted with LVDTs in the manner described in Example 1. As shown in FIG. 17, the outputs of these LVDTs indicate that the tiles were displaced independently of each other as opposed to that shown in Example 1. These test results thus show that these tiles of the present invention could be adapted to individual (microscale) bends without producing large bends.
[0049]
  floatingThe attachment mechanisms 68, 68 ′ and 68 ″ move the tiles 66, 66 ′ and 66 ″ relative to the wall 62.(Ie“Floating”)However, those skilled in the artfloatingIt will be appreciated that the attachment mechanisms 68, 68 'and 68 "preferably hold the tile 66 as close as possible to the surface of the tube 18 so that heat transfer through the tile 66 to the tube is maximized. .
[0050]
Furthermore, the above-mentioned pasted tile and the above-mentioned modified pasted tile structure can be used in combination with the present invention. Furthermore, the conventional bolted tile fastening device as described above is modified to provide an extra gap between the stud and the hole so that the tile can float with respect to the wall, thereby providing a space between adjacent tiles of the present invention. It can be used in combination with a corrosion barrier and a gap.
[0051]
The above description is primarily intended for illustrative purposes. While the invention has been illustrated and described in terms of exemplary embodiments thereof, it will be apparent to those skilled in the art that various modifications, omissions, and additions in form and detail may be made without departing from the spirit and scope of the invention. It should be understood that
Although the present invention has been described above, what is claimed is as follows.
[Brief description of the drawings]
FIG. 1 is a plan view of a prior art bolted refractory tile.
2 is a cross-sectional view of the refractory tile of FIG. 1 taken along line 2-2.
FIG. 3 is a cut-away side view of a prior art glued refractory tile.
4 is a cut top view of the glued refractory tile of FIG. 3. FIG.
FIG. 5 is a partially exploded perspective view in which a portion of a prior art modified refractory tile is collapsed and arranged to engage a boiler wall.
FIG. 6 is a view similar to FIG. 2, including a top view of an embodiment of the fireproof tiled structure of the present invention.
FIG. 7 is a view similar to FIG. 6 of another embodiment of the fireproof tiled structure of the present invention.
FIG. 8 is a perspective view of a row of prior art refractory tiles bent to a large scale established according to the present invention.
FIG. 9 is a schematic cross-sectional view similar to FIG. 2 of a portion of a pair of adjacent refractory tiles of the prior art, with portions shown in phantom lines to show improvements due to bending.
FIG. 10 is a view similar to FIGS. 6 and 7 of yet another embodiment of the fireproof tiled structure of the present invention.
11 is an exploded side view of a portion of the refractory tiled structure of FIG.
12 is a perspective view of the refractory tiled structure of FIGS. 10 and 11 at a stage performed during installation of the refractory tile of the present invention. FIG.
13 is a perspective view of the refractory tiled structure of FIGS. 10 and 11 at a stage performed during installation of the refractory tile of the present invention. FIG.
FIG. 14 is a perspective view of the refractory tiled structure of FIGS. 10 and 11 at a stage performed during installation of the refractory tile.
FIG. 15 is a perspective view of the refractory tiled structure of FIGS. 10 and 11 at a stage performed during the installation of the refractory tile.
FIG. 16 is a schematic front view of a series of conventional bolted tiles of FIGS. 1 and 2 attached to a boiler for testing.
17 is a graph of test results produced by the bolted tile of FIG.
FIG. 18 is a graph similar to FIG. 17 of the test results produced by the tile of the present invention.

Claims (5)

That are used on the walls of the boiler Te fire tiled structure smell,
And multiple tiles that have a engageable floating attachment mechanism to said wall,
A corrosion barrier disposed between the plurality of tiles and the wall ;
The floating mounting mechanism holds the plurality of tiles in a spaced apart relationship on the wall;
Wherein the plurality of tiles, have a size and shape to form a sufficient gap between adjacent said tiles to allow dimensional changes of the plurality of tiles arising during exposure to operating temperatures of boiler And
The corrosion barrier is a coating applied to the wall and formed from a coating that adheres to the wall but does not adhere to the plurality of tiles ;
Fireproof tiled structure characterized by It said floating attachment mechanism for holding the plurality of tiles in pairs City move possible spaced relation to the wall, the refractory tile structure according to claim 1. Wherein the plurality of tiles, between at least a portion and the wall thereof tile has a size and shape to form a sufficient second gap to allow the dimensional change, refractory tile according to claim 2 Upholstery structure. That are used on the walls of the boiler Te fire tiled structure smell,
A plurality of tiles disposed on the wall and movably spaced from each other ;
A corrosion barrier disposed between the plurality of tiles and the wall and substantially preventing corrosion of the wall ;
Wherein the plurality of tiles, the size and shape to form a sufficient clearance to substantially prevent bending large plurality of tiles during exposure to operating temperatures of boiler, between adjacent said tiles Have
The corrosion barrier is a coating applied to the wall and formed from a coating that adheres to the wall but does not adhere to the plurality of tiles ;
Fireproof tiled structure characterized by The useful life of the wall of the boiler Te method odor of enhancing,
(A) a plurality of tiles having engageable floating attachment mechanism to the wall, the steps of providing a plurality of tiles held in relation spaced movable to each other on the walls by the floating attachment mechanism ,
(B) such that a sufficient clearance to allow dimensional changes of the plurality of tiles that occurs during exposure to operating temperatures of the boiler is formed between adjacent said tiles, the dimensions of the plurality of tiles And setting the shape ;
(C) a coating which does not adhere to the plurality of tiles while adhering to the wall, comprising the steps of forming a coating on the wall, placing a corrosion barrier comprising a coating film on the wall,
(D) as the plurality of tiles is superimposed on the wall and the corrosion barrier is disposed between the plurality of tiles and wall, comprising the steps of engaging the floating attachment mechanism on the wall ,
Having a method.

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