JP2019173089A - Skid post - Google Patents

Abstract

To provide a skid post in which thermal insulation efficiency to a cooling pipe is increased, further, the movement of cyclic blocks is suppressed, and the peeling damage caused by the cracking of the cyclic blocks is suppressed.SOLUTION: A skid post 40 comprises: a water cooling pipe 50; a plurality of cyclic block parts 71 surrounding the cooling pipe 50 and provided so as to be laminated in the longitudinal direction of the water cooling pepe 50; and cyclic sheets 72 provided between the cyclic block parts 71 adjacent in the longitudinal direction of the water cooling pipe 50 and adhesively fixed between the cyclic block parts 71. Each cyclic block part 71 is a block made of a refractory with a height of 100 mm or lower. The height of the cyclic sheet 72 is 5 to 20 mm.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a skid in a heating furnace, and more particularly to a skid post in a heating furnace in a steel production process.

  In a steel production process, a heating furnace for rolling is equipment that reheats to a target temperature (usually about 1200 ° C.) in order to hot-roll a piece of steel that has been subjected to ingot rolling or continuously cast. For example, in a walking beam type heating furnace, a movable skid and a fixed skid are provided to convey a steel piece in the furnace, and the steel piece is forwardly conveyed intermittently by repeating a rectangular motion of the movable skid. .

  The skid includes a skid beam corresponding to a beam, and a skid post that supports the skid beam and corresponds to a column. For the skid post, a metal water-cooled pipe is used for the purpose of maintaining strength for supporting heavy objects, and the outer periphery thereof is covered and protected by an irregular refractory. If the skid post does not insulate the water-cooled pipe, heat removal from the heating furnace to the cooling water flowing in the water-cooled pipe increases, and heat loss increases. Therefore, heat insulation of the skid post in the heating furnace in the slab heating process is one of the important issues in an efficient energy saving process, that is, it is important that the refractory covering the skid post has good heat insulation. It becomes.

  As a heat insulating structure of a skid post, conventionally, a heat insulating structure in which a fire-resistant and heat-insulating castable (unshaped refractory) is supported by a metal support fitting (stud) welded and fixed to a water-cooled pipe is used. It is possible to reduce the heat removal from the heating furnace to the water-cooled pipe to some extent by using the fireproof heat insulating castable having a low thermal conductivity. However, since the thermal conductivity of the metal stud is high, heat removal from the stud cannot be ignored, which is one of the factors that increase heat loss. Further, in the structure in which the irregular refractory is supported on the skid post, a large number of studs are required for each skid post. For this reason, a lot of time and labor are required for the construction, and the construction cost becomes high.

  Therefore, for example, Patent Document 1 proposes a skid post that is made studless. The skid post has a configuration in which a plurality of annular block portions are stacked on the outer periphery of the water-cooled pipe in the longitudinal direction of the water-cooled pipe. The annular block portion is formed by connecting three or more divided blocks in the circumferential direction via joints, and the divided block is a CA6 precast block formed by precasting a refractory heat insulating castable containing CA6 aggregate. Consists of. Further, an expansion allowance is provided to absorb expansion of the annular block portion in the longitudinal direction of the water-cooled pipe by sandwiching an expansion absorbent between the annular block portions adjacent to each other in the longitudinal direction of the water-cooled pipe.

JP 2013-111282 A

  However, in the skid post described in Patent Document 1, an expansion allowance is provided between the annular block portions, but no restraining force acts on the annular block portion and the expansion allowance. As a result, during operation of the heating furnace, due to vibrations when carrying steel slabs or vibrations when the movable skid moves in a rectangular manner, the annular block portions (hereinafter referred to as a laminated structure) stacked in the outer diameter direction. There is a possibility that the divided blocks gradually move, and eventually the laminated structure collapses.

  Further, in the skid post described in Patent Document 1, CA6 quality precast blocks are used for the divided blocks. In the case of this material, cracks may occur in the divided blocks due to thermal spalling of the divided blocks due to furnace temperature fluctuations during operation of the heating furnace. If this crack develops and an intersection of cracks is generated, the divided blocks may be peeled off from around the intersection and damaged. Further, there is a concern that the energy saving performance is lowered due to the continuation of the peeling damage and the laminated structure is collapsed.

  The present invention has been made in view of the above circumstances, and in the skid post in the heating furnace, while improving the heat insulation efficiency for the cooling pipe, the movement of the annular block is suppressed, and the peeling damage caused by the crack of the annular block is caused. The purpose is to suppress.

  In the skid post, the present inventors install an annular sheet between annular blocks adjacent to each other in the longitudinal direction of the cooling pipe, and improve the heat insulation efficiency for the cooling pipe by bonding and fixing the annular block and the annular sheet. It was considered that the movement of the annular block can be suppressed and the peeling damage due to the crack of the annular block can be suppressed.

  In the skid post having the above-described configuration, the studless structure without using the support metal (stud) is realized, so that the heat insulation efficiency for the cooling pipe can be increased over a long period of time. Moreover, since the annular block and the annular sheet are bonded and fixed, the movement of the annular block in the outer diameter direction due to various vibrations or the like can be suppressed. Furthermore, even if the crack of the annular block develops due to the adhesive fixing to the annular sheet, the peeling damage of the annular block can be suppressed. And in order to implement | achieve appropriately that the movement of an annular block can be suppressed in this way and the peeling damage resulting from the crack of an annular block can be suppressed, the height of an annular block is 100 mm or less, and the height of an annular sheet Was found to require a condition of 5 mm or more and 20 mm or less, and the present invention was made. The basis for this numerical value will be described in the following embodiments and examples.

  The present invention is a skid post installed in a heating furnace, and includes a cooling pipe, a plurality of annular blocks that surround the cooling pipe and are stacked in the longitudinal direction of the cooling pipe, and the cooling pipe. An annular sheet provided between the annular blocks adjacent to each other in the longitudinal direction and bonded and fixed to the annular block. The annular block is a block made of a refractory having a height of 100 mm or less. The height of the annular sheet is 5 mm or more and 20 mm or less.

  In the skid post, the annular block may be a block manufactured by a vacuum forming method using a ceramic fiber as a base material.

  In the skid post, the annular sheet may be a mullite ceramic fiber blanket.

  In the skid post, the heat insulating layer further includes a heat insulating layer provided between an inner peripheral surface of the laminated structure including the plurality of annular blocks and the annular sheet, and an outer peripheral surface of the cooling pipe. May consist of any one or a combination of fumed siliceous, microporous, and ceramic fibers.

  In the skid post, an outer peripheral surface of the laminated structure including the plurality of annular blocks and the annular sheet may be covered with a mortar-shaped refractory.

  In the skid post, the annular block may be divided into a plurality in the circumferential direction.

  ADVANTAGE OF THE INVENTION According to this invention, while improving the heat insulation efficiency with respect to a cooling pipe in the skid post in a heating furnace, the movement of an annular block can be suppressed and the peeling damage resulting from the crack of an annular block can be suppressed.

It is a figure which shows the outline of a structure of the skid of the walking beam type heating furnace to which the skid post of this embodiment is applied. It is a figure which shows the structure of the skid post concerning this embodiment, (a) is a vertical sectional view, (b) is a partial vertical cross section and a partial side view, (c) is a horizontal sectional view. It is a figure which shows the structure of the laminated structure concerning this embodiment, (a) is a perspective view of a laminated structure, (b) is sectional drawing of an annular block part, (c) is a cross section of an annular sheet FIG. It is explanatory drawing which shows the effect of the laminated structure of this embodiment.

  Embodiments of the present invention will be described below with reference to the drawings. In the present specification and drawings, elements having substantially the same functional configuration are denoted by the same reference numerals, and redundant description is omitted.

  Based on FIGS. 1-3, the structure of the skid post concerning embodiment of this invention is demonstrated. FIG. 1 is a diagram showing a schematic configuration of a skid of a walking beam heating furnace to which the skid post of the present embodiment is applied. FIG. 2 is a diagram showing a configuration of the skid post according to the present embodiment. FIG. 3 is a view showing a configuration of a laminated structure of skid posts according to the present embodiment.

  As shown in FIG. 1, a plurality of rows of skids 20 for supporting and transporting the steel slab 10 are provided in the heating furnace. The skid 20 includes a movable skid 21 and a fixed skid 22, and the movable skid 21 repeats a rectangular motion in a vertical plane to intermittently convey the steel piece 10 forward. Each skid 20 (movable skid 21 and fixed skid 22) includes a skid beam 30 corresponding to a beam, and a skid post 40 that supports the skid beam 30 and corresponds to a pillar. Although a walking beam type heating furnace has been described as an example here as a typical heating furnace, a heating furnace to which the Kid Post of the present invention is applied is not limited to such an example. For example, the skid post of the present invention can be applied to a pusher-type heating furnace.

  The inside of the heating furnace becomes a high temperature of 1000 ° C. or more, for example. Therefore, as shown in FIG. 2, the skid post 40 includes a metal-made cylindrical water-cooled pipe 50 (corresponding to the cooling pipe of the present invention) made of steel or the like, and a heat insulating layer provided on the outer periphery of the water-cooled pipe 50. It is comprised by the part 60 (equivalent to the heat insulation layer of this invention) and the laminated structure 70 provided in the outer periphery of the heat insulation layer part 60 further. With this configuration, the skid post 40 can ensure the strength as a pillar even at high temperatures, and can suppress the heat in the heating furnace from being taken away through the cooling water in the water-cooled pipe 50. The cooling water in the water cooling pipe 50 is supplied and discharged through the skid beam 30. Note that the cooling pipe according to the present embodiment is configured by a water cooling pipe 50 that circulates cooling water as a refrigerant. However, the cooling pipe of the present invention is not limited to this example, and a liquid other than water or cooling as the refrigerant. Gas or the like may be circulated.

  The heat insulating layer 60 is provided in a cylindrical shape along the longitudinal direction of the water-cooled pipe between the inner peripheral surface of the laminated structure 70 and the inner peripheral surface of the water-cooled pipe 50. Note that a predetermined gap may be provided between the outer peripheral surface of the heat insulating layer 60 and the inner peripheral surface of the laminated structure 70. By providing such a gap, for example, even if a construction error or the like occurs in the water-cooled pipe 50 or the heat insulating layer 60, the construction error or the like can be absorbed by the gap, and then the laminated structure 70 can be appropriately constructed. . For example, even if a crack occurs in the laminated structure 70 (divided block 73 described later) and the heat insulating layer 60 partially thermally expands, the expansion can be absorbed by the gap.

  The heat insulation layer part 60 may be a single layer formed of one kind of heat insulating material, or may be a multiple layer formed by laminating a plurality of kinds of heat insulating materials. Insulating materials generally tend to have poor heat insulating performance as they can withstand high temperatures. For this reason, in order to improve the heat insulation performance of the heat insulation layer part 60, the heat insulation material of the comparatively low-temperature part near the water cooling pipe 50 uses a thing with high heat insulation performance, and the heat insulation performance is inferior to the outside, but heat resistance It is preferable to form the heat insulation layer part 60 using a high heat insulating material.

  In the present embodiment, as shown in FIG. 2, the heat insulating layer 60 has a two-layer structure including an inner layer 61 and an outer layer 62 laminated in the radial direction of the skid post 40 (water-cooled pipe 50). The inner layer 61 and the outer layer 62 are formed of a material having a lower thermal conductivity than the laminated structure 70 (a divided block 73 described later) while ensuring heat resistance in the temperature range at each installation position. With the heat insulating layer 60 having such a structure, the heat insulating performance of the skid post 40 can be improved. As the heat insulating material forming such a heat insulating layer portion 60, for example, fumed silica or microporous material having low heat resistance but high heat insulating property is used for the inner layer 61, and the outer layer 62 is used for protecting the inner layer 61. For example, ceramic fiber is used which has lower heat insulation than fumed siliceous but high heat resistance.

  As an example of the formation method of the heat insulation layer part 60, when using shaped materials, such as a heat insulation sheet or a ceramic fiber, if a shaped material is wound around a to-be-constructed body (water cooling pipe 50 grade | etc.,), And it fixes with an adhesive material etc. Good. In addition, when using an irregular shaped material, the irregular shaped material may be applied to or sprayed on the workpiece, or the installed laminated structure 70 is used as a mold, An indeterminate shape material may be poured between the peripheral surface and the outer peripheral surface of the water-cooled pipe 50.

  The laminated structure 70 surrounds the water cooling pipe 50 and the heat insulating layer 60, and is provided in a cylindrical shape along the longitudinal direction of the water cooling pipe on the outer periphery of the heat insulating layer 60. The laminated structure 70 includes a plurality of annular block portions 71 (corresponding to the annular block of the present invention) provided by being laminated in the longitudinal direction of the water-cooled pipe 50 (vertical direction in FIG. 2A), and water cooling. The pipe 50 includes a plurality of annular sheets 72 provided between the annular block portions 71 adjacent to each other in the longitudinal direction. That is, in the laminated structure 70, the annular block portions 71 and the annular sheets 72 are alternately stacked. FIG. 2A shows a lower portion of the laminated structure 70, and shows a state where the annular block portion 71 and the annular sheet 72 are laminated in four stages on the hearth 80 of the heating furnace.

  The annular block 71 and the annular sheet 72 adjacent to each other in the longitudinal direction of the water cooling pipe 50 are bonded and fixed. Although the method of this adhesion fixation is not specifically limited, For example, the said annular block part 71 and the annular sheet 72 are fixed by apply | coating a fireproof mortar to the contact surface of the annular block part 71 and the annular sheet 72. .

  As shown in FIGS. 2 and 3, the annular block portion 71 is divided into, for example, two divided blocks 73. The two divided blocks 73 are provided adjacent to each other in the circumferential direction via the joint portion 74 and constitute an annular block portion 71 that is an annular body. In the present embodiment, the divided blocks 73 have the same size and shape, but each divided block 73 may have a different size or shape as long as the annular block portion 71 can be formed. Absent. Further, the number of divided blocks 73 is not limited to this example, and may be three or more. However, the annular block portion 71 may be a single annular body without being divided. However, in consideration of workability, the annular block portion 71 is preferably divided into a plurality of pieces.

  The joint portion 74 is a joint portion of the divided blocks 73 adjacent to each other in the circumferential direction, and is provided between the circumferential end surfaces of the divided blocks 73. For the joint part 74, for example, a refractory mortar is used. Further, the joint portions 74 of the annular block portions 71 adjacent to each other in the longitudinal direction of the water-cooled pipe 50 are arranged at positions shifted in the circumferential direction so as not to overlap each other. For example, the joint portions 74 of the annular block portions 71 adjacent to each other in the vertical direction are arranged at positions where the angle from the center of the annular block portion 71 is shifted by 30 degrees in plan view. In each divided block 73, stress concentrates on the central position, and thus the joint 74 is stressed by shifting the position of the joint 74 from the central position of the divided block 73. Can be suppressed.

  As the material of the divided block 73 (annular block portion 71), a material having little thermal shrinkage even under a high temperature environment and having low thermal conductivity characteristics (high heat insulation characteristics) is used. An example of such a material is ceramic fiber. In particular, in a high temperature environment exceeding 1000 ° C., it is preferable to use a crystalline fiber. Crystalline fiber is a kind of ceramic fiber, and for example, thermal contraction in a high temperature environment exceeding 1000 ° C. is further less than that of amorphous fiber. The divided block 73 is preferably manufactured by a vacuum forming (VF) method using a ceramic fiber as a base material. The VF method is a dense ceramic fiber block produced by suspending a defibrated ceramic fiber in a solution of an organic binder and an inorganic binder, introducing the suspension into a vacuum forming mold, removing the frame and drying it. It is a manufacturing method. By the VF method, it is possible to suppress elastic deformation, which was a drawback when the ceramic fiber was used for a structure. In the following description, a block manufactured by the VF method may be referred to as a VF block.

  In addition, the block which precast the castable of normal fireproof property or fireproof heat insulation quality (for example, CA6 quality) is applicable to the division block 73. FIG. However, compared with such a block, the above-described VF block can suppress the thermal conductivity to about half, and the heat insulation is improved. For this reason, heat removal from the water-cooled pipe 50 can be suppressed.

  The height H1 of the divided block 73 (annular block portion 71) shown in FIG. 3B is 100 mm or less. When the height H1 of the divided block 73 is larger than 100 mm, the crack generated in the divided block 73 develops during operation of the heating furnace, and is further connected to the crack generated from another position, so There is a concern that a small piece of the divided block 73 that is in an adhesive state is generated, and that the small piece may be peeled off and damaged. The reason why the upper limit value is 100 mm will be described in an example described later. In addition, when the height H1 of the divided blocks 73 is small, the number of the divided blocks 73 in the laminated structure 70 increases and the construction becomes complicated. Therefore, the height H1 is desirably 40 mm or more.

  The annular sheet 72 is a single annular body (sheet). The annular sheet 72 has a fissure portion 75 penetrating from the inner peripheral surface to the outer peripheral surface. The crevice 75 is formed in consideration of construction. That is, since the annular sheet 72 is flexible due to the material described later, the annular sheet 72 is installed on the outer periphery of the water-cooled pipe 50 and the heat insulating layer part 60 so as to open the slit 75.

  As the material of the annular sheet 72, a material having a small thermal shrinkage even in a high temperature environment is used as in the divided block 73. Specifically, for example, a ceramic fiber blanket sheet (hereinafter referred to as a CFB sheet) made of mullite or the like is used for the annular sheet 72. However, in a high temperature environment where the operating temperature of the heating furnace is 1000 ° C. or more, the amorphous fiber blanket of the CFB sheet is thermally contracted, and a gap is generated between the annular block portions 71, and the inside of the heating furnace is generated from the gap. There is a concern that the water-cooled pipe 50 is heated by the intrusion of high-temperature hot air, and is oxidized and damaged. For this reason, in a high temperature environment exceeding 1000 ° C., it is desirable to apply a crystallized fiber blanket having an extremely small thermal shrinkage rate to the annular sheet 72.

  The height H2 of the annular sheet 72 shown in FIG. 3C is 5 mm or more and 20 mm or less. When the height H2 of the annular sheet 72 is smaller than 5 mm, the drop of the tensile strength of the annular sheet 72 itself prevents the movement of the divided blocks due to various vibrations during operation of the heating furnace, and the annular sheet 72 breaks. There is a fear. Here, in this embodiment, since the annular sheet 72 adheres and fixes the divided block 73 (annular block portion 71) as will be described later, there is an effect of suppressing the movement of the divided block 73 in the outer diameter direction due to various vibrations. is there. In this regard, if the annular sheet 72 is broken, the effect of suppressing the movement of the divided block 73 (annular block portion 71) cannot be enjoyed. Moreover, when the height H2 of the annular sheet 72 is larger than 20 mm, the working surface area of the annular sheet 72 is enlarged, and the contact area with the scale scattered in the heating furnace is increased. Silica contained in the annular sheet 72 reacts with the scale to produce a low melting point compound. For this reason, there is a concern that infiltration damage due to the low melting point compound proceeds from the surface of the annular sheet 72. The grounds for these lower limit value 5 mm and upper limit value 20 mm will be described in the examples described later.

  In addition, the outer diameter D1 and the inner diameter D2 of the divided block 73 (annular block portion 71) shown in FIGS. 3B and 3C are the same as the outer diameter D1 and the inner diameter D2 of the annular sheet 72, respectively. The thickness of the divided block 73 and the annular sheet 72 (difference between the outer diameter D1 and the inner diameter D2) depends on the diameter of the water-cooled pipe 50, the heat insulating performance of the laminated structure 70 (fireproof heat insulating material), and the heat insulating layer 60 (back heat insulating material). ) Is determined in consideration of the heat-resistant temperature.

  When constructing the laminated structure 70, after forming the heat insulating layer portion 60 on the outer periphery of the water-cooled pipe 50, the annular sheet 72 is installed on the outer periphery of the heat insulating layer portion 60 so as to open the fissure portion 75. . The annular sheet 72 is bonded and fixed to the hearth 80 by applying a refractory mortar between the lower surface of the annular sheet 72 and the fixed surface of the hearth 80 (absolute fixing part), for example. Subsequently, on the upper surface of the annular sheet 72, two divided blocks 73 are installed from both sides of the outer periphery of the heat insulating layer portion 60. And a fireproof mortar is apply | coated to the joint part 74 of these two division | segmentation blocks 73, and the annular block part 71 is formed. Further, by applying a refractory mortar to the contact surface between the annular block portion 71 and the annular sheet 72, the annular block portion 71 and the annular sheet 72 are bonded and fixed. In this way, the annular sheets 72 and the annular block portions 71 are alternately laminated to form an integrated laminated structure 70.

  Next, the effect of the skid post 40 of the present embodiment configured as described above will be described.

  According to the skid post 40 of the present embodiment, the heat insulation efficiency with respect to the water-cooled pipe 50 is increased because the heat-insulating layer portion 60 and the laminated structure 70 each having the above-described material are provided on the outer periphery of the water-cooled pipe 50. . In addition, since the studless structure without using the support fitting (stud) is realized, the heat insulation performance for the water-cooled pipe 50 can be enhanced over a long period of time. As a result, it is possible to suppress heat removal from the heating furnace to the cooling water, enjoy the maximum heat loss reduction effect, and improve energy saving performance.

  In addition, as in the conventional case described above, when no restraining force is applied between the annular block portions, the divided blocks may gradually move in the outer diameter direction due to various vibrations during operation of the heating furnace. In this respect, in the laminated structure 70 of the present embodiment, the divided block 73 (annular block portion 71) is bonded and fixed to the annular sheet 72, and the lowermost annular sheet 72 is bonded and fixed to the hearth 80. The divided block 73 does not move in the outer diameter direction. As a result, collapse of the laminated structure 70 can be suppressed and durability can be improved.

  Moreover, in the laminated structure 70 of this embodiment, the progress of the crack from the division | segmentation block 73 can be suppressed and the peeling damage of the division | segmentation block 73 can be suppressed. This effect will be described with reference to FIG. FIG. 4 is an explanatory view showing the effect of the laminated structure 70 of the present embodiment.

  As described above, during operation of the heating furnace, cracks C may occur in the divided block 73 due to thermal spalling of the divided block 73 due to temperature fluctuation in the furnace. The crack C generated in the divided block 73 develops and is connected to a crack generated from another position, thereby generating a small piece of the divided block 73 that is in an unbonded state with the annular sheet 72, and the small piece is peeled off. Damage may occur.

  As shown in FIG. 4, when the laminated structure 70 of the present embodiment is used, even if the crack C generated in the divided block 73 develops and is connected to a crack generated from another position, a small piece is generated. Since it is adhesively fixed to 72, peeling of small pieces can be suppressed. As a result, the thickness of the laminated structure 70 in the radial direction hardly changes, and high energy saving performance can be maintained over a long period of time. Further, it is possible to improve the durability by suppressing the collapse of the laminated structure 70.

  In addition, as described above, the annular sheet 72 of the present embodiment suppresses the movement of the divided block 73 in the outer diameter direction due to various vibrations and the like. Although there is an effect that the peeling damage can be suppressed, there is also an effect that the thermal expansion in the height direction of the divided block 73 is absorbed.

  Next, the configuration of a skid post according to another embodiment of the present invention will be described. The outer peripheral surface of the laminated structure 70 is exposed to the atmosphere in the heating furnace and comes into contact with a scale that scatters in the heating furnace. In order to suppress damage due to the scale, the outer peripheral surface of the laminated structure 70 may be covered with a mortar-like refractory material having high scale resistance such as alumina or spinel (hereinafter referred to as refractory mortar). Good. In particular, a VF block with low scale resistance is used for the divided block 73 of the present embodiment, and it is useful to coat the outer peripheral surface of the divided block 73 with refractory mortar in this way. In addition, although the thickness of the radial direction of this refractory mortar is not specifically limited, For example, it is 2 mm-3 mm.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to this example. It is obvious for those skilled in the art that various changes or modifications can be conceived within the scope of the technical idea described in the claims. It is understood that it belongs to.

  Examples of the present invention will be described below. The present invention is applied to a heat insulating structure of a skid post in a walking beam type heating furnace. This heating furnace is a furnace in which the inside of the furnace is maintained at 1100 to 1300 ° C and the steel slab is heated to 1000 to 1200 ° C. COG (Coke Even Gas) is used as fuel, and the inside of the furnace is heated by a burner on the side wall.

  Table 1 shows heat insulating structures (heat insulating layer portions and laminated structures) of skid posts according to examples and comparative examples of the present invention. Table 1 shows two items as evaluation items.

  The first evaluation item is to evaluate the heat insulation characteristics of the skid post structure, and is the overall thermal resistance index. The overall thermal resistance index is calculated from the thermal conductivity λ of the material constituting the heat insulating structure, and the overall thermal resistance index of Comparative Example 1 is set to 1.00 (reference).

The second evaluation item is to evaluate the durability of the heat insulating structure, and shows the condition of the split block and the annular sheet of the skid post one year after the operation of the heating furnace. Specific evaluation items are the following (1) to (4). In Table 1, when it is determined that all of these items are “none”, “◯” is indicated. On the other hand, when it is determined that at least one is “present”, “x” and items corresponding to the “x” are indicated.
(1) Is there any movement in the outer diameter direction of the divided blocks due to various vibrations during heating furnace operation?
(2) Is there a partial separation of the divided block due to the progress of cracks in the divided block?
(3) Is there damage to the annular sheet due to scale infiltration into the annular sheet?
(4) Is there a break in the annular sheet due to various vibrations during heating furnace operation?

  In Comparative Examples 1 to 5 and Examples 1 to 5, a 15 mm thick fumed siliceous heat insulating sheet is fixed to a water-cooled pipe with a nylon band as the first layer of the heat insulating structure (the inner layer 61 of the heat insulating layer 60). Then, a crystallized fiber sheet having a thickness of 12.5 mm was attached and fixed as a second layer (the outer layer 62 of the heat insulating layer 60) on the surface. On the other hand, in the comparative examples 1-5 and Examples 1-5, the structure of the 3rd layer (the said laminated structure 70) of a heat insulation structure differs, respectively.

  Comparative Example 1 is a conventional laminated structure, and a CA6 castable precast block having a height of 300 mm is used as a divided block, and no annular sheet is provided. In this case, in the durability evaluation, in the item (1), the divided blocks adjacent to each other in the height direction are not fixed, and thus the divided blocks have moved in the outer diameter direction. In item (2), the height of the divided block was 300 mm larger than the upper limit value of 100 mm, and partial separation of the divided block occurred.

  In Comparative Example 2, a VF block having a height of 200 mm was used as a divided block, and a crystallized fiber blanket having a height of 20 mm was used as an annular sheet, and these divided blocks and the annular sheet were bonded and fixed. In such a case, in the heat insulation property evaluation, since the material having high heat insulation is used for the divided block and the annular sheet, the overall thermal resistance index is larger than 1, and the heat insulation is improved. In the durability evaluation, in the item (1), the divided block did not move because the divided block and the annular sheet were bonded and fixed. Further, in items (3) and (4), since the height of the annular sheet 20 mm was within the predetermined range 5 mm to 20 mm, the annular sheet was neither damaged nor broken. On the other hand, in item (2), the height of the divided blocks of 200 mm was larger than the upper limit value of 100 mm, and partial separation of the divided blocks occurred.

  In Comparative Example 3, a VF block having a height of 50 mm was used as a divided block, and a crystallized fiber blanket having a height of 30 mm was used as an annular sheet, and these divided blocks and the annular sheet were bonded and fixed. In such a case, in the heat insulation property evaluation, since the material having high heat insulation is used for the divided block and the annular sheet, the overall thermal resistance index is larger than 1, and the heat insulation is improved. In the durability evaluation, in the item (1), the divided block did not move because the divided block and the annular sheet were bonded and fixed. In item (2), the height of the divided blocks was 50 mm smaller than the upper limit value of 100 mm, and partial separation of the divided blocks did not occur. On the other hand, in item (3), the height of the annular sheet 30 mm was larger than the upper limit 20 mm, and the annular sheet was damaged due to the infiltration of the scale.

  In Comparative Example 4, a VF block having a height of 50 mm was used as the divided block, and a crystallized fiber blanket having a height of 4 mm was used as the annular sheet, and these divided blocks and the annular sheet were bonded and fixed. In such a case, in the heat insulation property evaluation, since the material having high heat insulation is used for the divided block and the annular sheet, the overall thermal resistance index is larger than 1, and the heat insulation is improved. In the durability evaluation, in item (2), the height of the divided block was 50 mm smaller than the upper limit value of 100 mm, and the partial separation of the divided block did not occur. On the other hand, in item (4), the height of the annular sheet was 4 mm smaller than the lower limit of 5 mm, and the annular sheet was broken. As a result, also in item (1), movement of the divided blocks in the outer diameter direction was recognized.

  In Comparative Example 5, a VF block having a height of 50 mm was used as the divided block, a crystallized fiber blanket having a height of 10 mm was used as the annular sheet, and the divided block and the annular sheet were not bonded and fixed. In such a case, in the heat insulation property evaluation, since the material having high heat insulation is used for the divided block and the annular sheet, the overall thermal resistance index is larger than 1, and the heat insulation is improved. In the durability evaluation, in the item (1), the divided block moved because the divided block and the annular sheet were not bonded and fixed. On the other hand, in item (2), the height of the divided block was 50 mm smaller than the upper limit value of 100 mm, and partial separation of the divided block did not occur. Further, in items (3) and (4), since the height of the annular sheet 10 mm was within the predetermined range 5 mm to 20 mm, the annular sheet was not damaged and did not break.

  In each of Examples 1 to 5, the height of the divided blocks was set to an upper limit value of 100 mm or less, the height of the annular sheet was set within a predetermined range of 5 mm to 20 mm, and these divided blocks and the annular sheet were bonded and fixed. In such a case, none of items (1) to (4) corresponded to the durability evaluation. That is, the divided block did not move in item (1), partial separation of the divided block did not occur in item (2), and the annular sheet was not damaged or broken in items (3) and (4). From the above results, it was confirmed that the skid post of the present invention was excellent in durability.

  In the second to fifth embodiments, a VF block is used as a divided block, whereas in the first embodiment, CA6 castable is used as a divided block. In addition, the crystallized fiber blanket was used for the annular sheet in common with Examples 1-5. In such a case, in Example 1, since the heat insulation property of CA6 castable was low, the overall thermal resistance index of the heat insulation property evaluation was 1.02, which was almost the same heat insulation property as Comparative Example 1. In addition, it is speculated that the heat insulation was slightly improved because a crystallized fiber blanket having a lower thermal conductivity than the CA6 castable was used for the annular sheet. On the other hand, in Examples 2-5, since the material with high heat insulation was used for the division | segmentation block and the cyclic | annular sheet | seat, the overall thermal resistance index became larger than 1, and heat insulation improved. From the above results, it was confirmed that the skid post of the present invention was excellent in heat insulation.

  The present invention can be applied to a skid post installed in a heating furnace.

DESCRIPTION OF SYMBOLS 10 Steel bill 20 Skid 21 Movable skid 22 Fixed skid 30 Skid beam 40 Skid post 50 Water cooling pipe 60 Heat insulation layer part 61 Inner layer 62 Outer layer 70 Laminated structure 71 Annular block part 72 Annular sheet 73 Divided block 74 Joint part 75 Crevice part 80 Hearth

Claims (6)

A skid post installed in a heating furnace,
Cooling pipes,
A plurality of annular blocks that surround the cooling pipe and are stacked in the longitudinal direction of the cooling pipe; and
An annular sheet provided between the annular blocks adjacent to each other in the longitudinal direction of the cooling pipe and bonded and fixed between the annular blocks;
The annular block is a block made of a refractory having a height of 100 mm or less,
The skid post, wherein the annular sheet has a height of 5 mm or more and 20 mm or less. The skid post according to claim 1, wherein the annular block is a block manufactured by a vacuum forming method using a ceramic fiber as a base material. The skid post according to claim 1, wherein the annular sheet is a mullite ceramic fiber blanket. A heat insulating layer provided between an inner peripheral surface of the laminated structure including the plurality of annular blocks and the annular sheet, and an outer peripheral surface of the cooling pipe;
The skid post according to any one of claims 1 to 3, wherein the heat insulating layer is made of any one or a combination of fumed siliceous, microporous, and ceramic fibers. The outer peripheral surface of the laminated structure including the plurality of annular blocks and the annular sheet is covered with a mortar-like refractory, according to any one of claims 1 to 4. Skid post. The skid post according to any one of claims 1 to 5, wherein the annular block is divided into a plurality in the circumferential direction.

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