Expansion structure for absorbing thermal expansion and contraction

Abstract

To disclose an expansion structure for absorbing thermal expansion and contraction capable of maintaining sealing performance without deforming a sealing material during absorption of thermal expansion and contraction.SOLUTION: An expansion structure is provided at a connection portion of a facility where a connection portion between a primary side and a secondary side thermally expands relatively in a vertical direction and a horizontal direction. The primary-side connection portion comprises a downward opening at a separated position separated by a gap that absorbs the vertical thermal expansion of the secondary-side connection portion. An outward-facing flange is provided on an outer periphery of an end part of the opening, and a holding frame made of a sealing material that closes the gap is attached to a lower surface side of the flange. The flange has a mounting shaft for the holding frame protruding from the lower surface side, and the holding frame is provided with a long hole through which the mounting shaft is slidably inserted. The long hole has a length and / or a width that absorb the horizontal thermal expansion of the primary-side connection portion.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an expansion structure that absorbs thermal expansion and contraction of a furnace, and more particularly to a structure that suppresses deformation and movement of a sealing material portion when absorbing thermal expansion and contraction. [Background technology]

[0002] Expansion structures that absorb the thermal expansion and contraction of furnaces are known (see, for example, Patent Documents 1 and 2).

[0003] On the other hand, Fig. 5 shows an outline of a waste treatment facility consisting of a rotary kiln incinerator, which is an associated facility of the present applicant. Thermal energy (waste heat) generated in a secondary combustion furnace 20 is recovered in a boiler 22 through a flue 21 to generate electricity and to be effectively utilized. An expansion structure 23 is provided at the connection between the flue 21 and the waste heat boiler 22 to absorb furnace thermal expansion and contraction. Fig. 6 shows a vertical cross-sectional view (Fig. 6(a)) and a horizontal cross-sectional view (Fig. 6(b)) of the expansion structure 23 and the vicinity thereof. As shown in the enlarged cross-sectional view of Fig. 7, a ceramic yarn rope is used as a sealing material 24, and in order to accommodate this inside the vertical part and flange 26 of an L-shaped cross-sectional angle metal fitting 27 fixed to a flange 26 of a can body 25 on the secondary combustion furnace side of the flue 21, a pressing plate 28 is attached to the horizontal part of the angle metal fitting 27 by combining a bolt 29 with a washer and a nut to prevent the sealing material 24 from falling. The heads of the bolts 29 are welded to the horizontal parts of the angle fittings 27, while the retaining plate 28 has slots 30 through which the shafts of the bolts 29 are inserted and a nut is manually screwed in via a washer, supporting the retaining plate 28 from below while allowing the secondary combustion furnace side body 25 to move horizontally relative to one another. Also, between the refractories 31 and 32 provided on the inner walls of the secondary combustion furnace side body and the boiler side body is a space 33 that is appropriate for thermal expansion and contraction, and at the beginning of construction, a ceramic hardboard (not shown) is inserted into this space 33 to reliably prevent leakage of heat and gas.

[0004] Because the end of the pressure plate 28 on the boiler side is free, if the boiler 22 thermally expands in the vertical direction, the vertical gap of the space 33 shrinks, absorbing the vertical thermal expansion (Fig. 8). Note that as such vertical thermal expansion and contraction is repeated, the ceramic hard board disappears, leaving the space 33, but the sealing material 24 continues to prevent leakage of gas, etc.

[0005] On the other hand, if the secondary combustion furnace side boiler body 25 expands horizontally due to heat, the angle bracket 27 also moves horizontally, and the bolts 29 slide along the long holes 30 provided in the pressure plate 28, absorbing the horizontal thermal expansion (Fig. 9). Here, the pressure plate 28 is held without moving horizontally by its own weight and the weight of the sealing material 24. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Utility Model Application Publication No. 4-115205 [Patent Document 2] Japanese Patent Application Publication No. 11-304126 Summary of the Invention [Problem to be solved by the invention]

[0007] As described above, the conventional expansion structure absorbs thermal expansion and contraction in both the vertical and horizontal directions, but when the secondary combustion furnace side can body 25 thermally expands (moves) in the horizontal direction, the sealing material 24 is compressed and deformed on one side of the expansion structure (the right side in Fig. 9), and as this process is repeated, the sealing material 24 deteriorates. Also, on the opposite side to where the sealing material 24 is compressed (the left side in Fig. 9), a gap is generated between the sealing material 24 and the angle fitting 27 (vertical part) in proportion to the horizontal movement distance, and the sealing performance of this part decreases.

[0008] As described above, conventional expansion structures absorbed furnace thermal expansion and contraction by utilizing the deformation of the sealing material, and therefore had the problem of deterioration of sealing performance over time.

[0009] The present invention has been made to solve the above-mentioned problems, and its purpose is to disclose an expansion structure for absorbing furnace thermal expansion that maintains sealing performance without deforming the sealing material when absorbing furnace thermal expansion. [Means for solving the problem]

[0010] In order to achieve the above-mentioned object, the expansion structure of the present invention is provided at a connection part of equipment in which the connection part between the primary side and secondary side expands and contracts relatively in the vertical and horizontal directions due to heat, and the primary side connection part has a downward opening at a spaced position separated by a gap that absorbs the vertical thermal expansion of the secondary side connection part, and an outward flange is provided on the outer periphery of the end of the opening, and a retaining frame of a sealing material that closes the gap is attached to the underside of the flange, and a mounting shaft of the retaining frame protrudes from the underside of the flange, and the retaining frame is provided with a long hole through which the mounting shaft can be slidably inserted, and the long hole has a length and / or width that absorbs the horizontal thermal expansion of the primary side connection part.

[0011] As described above, the present invention is based on the premise that it is applied to a connection part where one moves vertically and horizontally relative to the other due to thermal expansion. More specifically, it is provided at the connection part between the flue connecting the combustion furnace and the boiler and the boiler. In this case, it is an expansion structure that absorbs the vertical thermal expansion of the boiler and the horizontal thermal expansion of the flue. The absorption of the horizontal thermal expansion is to absorb the phenomenon in which the end of the flue, i.e., the central axis of the opening, is displaced horizontally. The flue is provided with an opening facing downward, which discharges waste heat from the combustion furnace to the boiler, at a position separated from the upper end of the boiler by a gap that absorbs the vertical thermal expansion of the boiler, and an outward flange is provided on the outer periphery of the end of the opening, and a retaining frame of a seal material with a rectangular cross section that closes the gap is attached to the underside of the flange. In this means, the holding frame includes a top plate portion attached to the underside of the flange, a side plate portion extending downward from the top plate portion to sandwich the sealing material with the boiler in the thickness direction, and a jaw portion extending inward from the side plate portion to sandwich the sealing material with the flange in the up-down direction. The flange has a mounting shaft for the holding frame protruding from its underside, and the top plate portion has a long hole through which the mounting shaft is slidably inserted. In particular, the long hole has a length and / or width that absorbs the thermal expansion of the flue in the horizontal direction. As a result, when the flue thermally expands in the horizontal direction, the opening moves horizontally independently within the range of the long hole while the boiler remains fixed, and as a result, it is possible to suppress the displacement of the holding frame and the sealing material from their original positions and the deformation of the sealing material. Of course, such an effect is exerted not only during thermal expansion (thermal expansion) but also during subsequent contraction due to cooling.

[0012] As a preferred configuration to be added to the above means, refractories with convex and concave surfaces facing each other across a gap are provided on the inner wall of the flue opening and the upper end of the boiler. This prevents the heat radiation from the furnace from directly hitting the flue opening and the upper end of the boiler, and also reduces the effect of the heat radiation from the furnace on the sealing material because the gap between the refractories is bent.

[0013] Moreover, it is preferable that the jaw portion of the holding frame is detachable from the side plate portion, because by removing the jaw portion, maintenance such as replacement or repair of the sealing material can be easily performed.

[0014] Furthermore, the sealing material is preferably made by covering a heat insulating blanket with a heat resistant cloth, since this makes it possible to achieve a high degree of both sealing performance and durability.

[0015] Furthermore, it is preferable to provide a rainwater protection part with an L-shaped cross section that covers at least the top plate part of the holding frame on the extension of the flange, because this can prevent the long hole and the mounting shaft from rusting due to rainwater, etc., and hindering the horizontal movement of the flue opening. Effect of the Invention

[0016] According to the present invention, the movement and deformation of the sealing material when a furnace or the like repeatedly undergoes thermal contraction is significantly suppressed compared to conventional methods, and the gap in the sealing portion is maintained constant, thereby significantly improving the deterioration of sealing performance. [Brief description of the drawings]

[0017] [Figure 1] A cross-sectional view of the main part of a facility to which an expansion structure according to one embodiment of the present invention is applied. [Diagram 2] Partially enlarged cross-sectional view [Diagram 3] Operation diagram (vertical thermal expansion) [Figure 4] Operation diagram (horizontal thermal expansion) [Diagram 5] Schematic diagram of existing waste treatment facility [Figure 6] Cross-sectional view of the existing expansion structure in the existing facility. [Figure 7] Enlarged cross-sectional view of the conventional expansion structure. [Figure 8] An explanatory diagram of the operation of the conventional expansion structure (vertical thermal expansion) [Figure 9]An explanatory diagram of the operation of the conventional expansion structure (horizontal thermal expansion) DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] A preferred embodiment of the present invention will be described below with reference to the attached drawings. The expansion structure of the present invention can be applied to the connection between the flue and the boiler, as in the facility shown in Figures 5 and 6, so the description of the entire facility will be omitted and the main parts will be described in detail. Figure 1 is a cross-sectional view of an expansion structure according to one embodiment of the present invention, in which 1 is a secondary combustion furnace body, 2 is a boiler body, and 3 is an expansion structure. The secondary combustion furnace body 1 is a part of the flue that connects the secondary combustion furnace and the boiler described in Figures 5 and 6, and means a downward opening that discharges waste heat from the secondary combustion furnace to the boiler. The boiler body 2 means an opening that is connected to the boiler body, and is a part that faces the secondary combustion furnace body 1 and introduces the above-mentioned waste heat into the boiler body. These bodies 1 and 2 are provided with refractories 4 and 5 on the inner walls to suppress the influence of heat radiation inside the furnace.

[0019] The refractories 4 and 5 are spaced apart from each other with a predetermined gap between them, i.e., a vertical clearance C1 that absorbs the thermal expansion of the boiler body in the vertical direction due to furnace heat. In this embodiment, the opposing surfaces are provided with convex and concave portions in a congruent shape as a more effective heat countermeasure. The opposing surfaces may be flat, but by making the surfaces convex and concave in a congruent shape, the gap shape is bent, making it difficult for thermal radiation to be transmitted to the boiler body. The vertical distance between the convex parts 4a and 5a and the concave parts 4b and 5b is set to the above-mentioned vertical clearance C1, and the horizontal distance between the convex parts 4a and 5a on one side (left side in Fig. 2) is set to a left-right clearance C2 that absorbs the thermal expansion of the secondary combustion furnace body 1 in the horizontal direction. The extent to which the secondary combustion furnace body 1 and the boiler body 2 expand due to heat can be calculated in advance by calculations related to thermal expansion, etc., so the clearances C1 and C2 can also be calculated at the design stage.

[0020] Next, further configuration of the expansion structure 3 will be described in detail. This structure is uniformly provided around the entire circumference of the secondary combustion furnace body 1 as the main mounting destination, so for convenience of explanation, the configuration will be described in detail with reference to Fig. 2 showing a partially enlarged cross-sectional view. First, an outward flange 1a is integrally provided around the outer circumference of the lower end of the secondary combustion furnace body 1. Then, the head of the bolt B is welded to the upper surface while being inserted from the upper surface until it protrudes from the lower surface. The lower surface of the flange 1a is flush with the recess 4b of the refractory 4.

[0021] A retaining frame 7 that holds a sealing material 6 is attached to the flange 1a. The sealing material 6 closes the upper and lower clearances C1 between the refractories 4 and 5 directly below the flange 1a, preventing heat, gas, and the like inside the furnace from leaking to the outside. In this embodiment, a ceramic fiber heat-insulating blanket covered with a heat-resistant cloth made of the same ceramic fiber and having a rectangular cross section is used as the sealing material 6, but other configurations can be used as long as they have equivalent heat resistance or heat insulation properties.

[0022] Meanwhile, the retaining frame 7 is attached to the flange 1a with the bolt B as the mounting shaft. In this embodiment, a top plate portion 7a, a side plate portion 7b, and a jaw portion 7c are configured to hold the sealing material 6 in the above-mentioned closed position. A long hole 7d is formed in the top plate portion 7a, and the retaining frame 7 is attached to the underside of the flange 1a by inserting the bolt B into the long hole 7d, passing a washer 8 through the bolt B, and screwing a double nut 9 into the bolt B. The long hole 7d allows the insertion portion of the bolt B to move, and allows the secondary combustion furnace body 1 to move horizontally relative to the boiler body 2. Therefore, the dimension (length and / or width) of the long hole 7d is set to be equal to or greater than the thermal elongation of the secondary combustion furnace body 1.

[0023] The side plate portion 7b of the retaining frame 7 sandwiches the sealing material 6 with the boiler body 2 in the thickness direction, and the jaw portion 7c sandwiches the sealing material 6 with the flange 1a in the vertical direction. The jaw portion 7c prevents the sealing material 6 from falling, and the end portion on the boiler body 2 side is cut off with a gap g provided between the boiler body 2 and the jaw portion 7c.

[0024] In the holding frame 7, the top plate 7a, the side plate 7b, and the jaw 7c can be integrally formed by bending a single steel plate, or the steel plates for each part may be joined together by welding or the like. In this respect, in this embodiment, the side plate 7b is bent to have an L-shaped cross section, and the extension of the jaw 7c is fixed to the lower horizontal part with a bolt nut 10. In this case, it is preferable to fix the jaw 7c at two or more points as in this embodiment. If it is fixed at only one point, the jaw 7c will rotate around the fixed part, which may lead to the seal material 6 falling off or the fluid leaking. With this configuration, the jaw 7c can be removed to easily perform maintenance such as replacing the seal material 6.

[0025] Furthermore, in consideration of the fact that a combustion facility to which this expansion structure is applied is constructed outdoors and is exposed to rainwater, in this embodiment, a rainwater protection part 11 with an L-shaped cross section is provided on the extension of the flange 1a as a canopy to protect the holding frame 7 from rainwater. This rainwater protection part 11 allows rainwater on the flange 1a to flow out to the outside of the holding frame 7, preventing the top plate part 7a (especially the long hole 7d) from rusting.

[0026] According to the expansion structure of the embodiment described above, if the boiler body 2 thermally expands in the vertical direction, it can continue to expand up and down as it is, as shown in Fig. 3. At this time, the movement of the sealing material 6 and its retaining frame 7 is suppressed.

[0027] In addition, since the secondary combustion furnace body 1 and the holding frame 7 are attached via the elongated hole 7d, as shown in Figure 4, if the secondary combustion furnace body 1 thermally expands in the horizontal direction, it can continue to expand to the left and right. At this time, the movement of the sealing material 6 and its holding frame 7 is suppressed. Also, the compressive deformation of the sealing material 6 is suppressed.

[0028] As described above, the expansion structure of the present invention suppresses the movement of the sealing material 6 when absorbing thermal expansion, so no gaps are generated during thermal expansion and the sealing performance is always good. In addition, deformation of the sealing material 6 is suppressed, so the performance of the sealing material 6 itself is maintained.

[0029] In the above embodiment, a waste heat boiler is provided as a device connected to the secondary side of the expansion structure. This is because, in response to the increasing need for reuse of thermal energy (waste heat) in recent years, the thermal energy (waste heat) discharged from the secondary combustion furnace is recovered and reused by the waste heat boiler. However, in the present invention, the secondary side device of the expansion structure is not limited to the waste heat boiler. In other words, if waste heat recovery is not performed, the waste heat boiler may be replaced with another device. For example, even if it is replaced with a quenching tower device, the expansion structure of the present invention can absorb the thermal expansion and contraction in the vertical and horizontal directions that occurs at the connection end (can body) of the replaced device, and the deterioration of the sealing performance can be significantly improved. [Explanation of symbols]

[0030] 1 Secondary combustion furnace body 1a Flange 2 Boiler body 3 Expansion structure 4 Refractories (secondary combustion furnace body side) 4a Refractory protrusion (secondary combustion furnace body side) 4b Refractory recess (secondary combustion furnace body side) 5 Refractories (boiler body side) 5a Refractory protrusion (boiler body side) 5b Refractory recess (boiler body side) 6. Sealing materials 7 Holding frame 7a Top plate 7b Side plate part 7c Jaw 7d long hole 8 Washer 9 Double Nut 10 Bolts and nuts 11 Rainwater Protection Department C1 Vertical clearance C2 Left and right clearance B Bolt g Gap 20 Secondary Combustion Furnace 21 Flue 22 Waste heat boiler 24 Sealing material 25 Secondary combustion furnace side boiler body 26 Flange 27 Angle bracket 28 Presser plate 29 Volts 30 long hole 31 Refractories (secondary combustion furnace body side) 32 Refractories (boiler body side) 33 Space

Claims

1. An expansion structure provided at a connection portion between a primary side and a secondary side of equipment in which the connection portion relatively expands vertically and horizontally, the primary side connection portion has a downward opening at a spaced position separated by a gap for absorbing thermal expansion of the secondary side connection portion in the vertical direction; an outward flange is provided on the outer periphery of the end of the opening, and a retaining frame for a seal material that closes the gap is attached to the underside of the flange; The flange has a mounting shaft for the holding frame protruding from its lower surface side, The holding frame is provided with a long hole through which the mounting shaft is slidably inserted, An expansion structure characterized in that the long hole has a length and / or width sufficient to absorb horizontal thermal expansion of the primary side connection portion.

2. An expansion structure is provided at a connection between a flue connecting a combustion furnace and a boiler and the boiler, and absorbs the vertical thermal expansion of the boiler and the horizontal thermal expansion of the flue, the flue has an opening facing downward, at a position separated from an upper end of the boiler by a gap for absorbing thermal expansion of the boiler in the vertical direction, for discharging waste heat from the combustion furnace to the boiler; an outward flange is provided on the outer periphery of the end of the opening, and a retaining frame of a sealing material having a rectangular cross section that closes the gap is attached to the underside of the flange; the retaining frame includes a top plate portion attached to the underside of the flange, a side plate portion extending downward from the top plate portion to sandwich the sealing material with the boiler in a thickness direction, and a jaw portion extending inward from the side plate portion to sandwich the sealing material with the flange in a top-bottom direction, The flange has a mounting shaft for the holding frame protruding from its lower surface side, The top plate portion is provided with a long hole through which the mounting shaft is slidably inserted, An expansion structure for absorbing furnace thermal expansion and contraction, characterized in that the long hole has a length and / or width sufficient to absorb the thermal expansion of the flue in the horizontal direction.

3. 3. The expansion structure for absorbing furnace thermal expansion and contraction according to claim 2, wherein the opening of the flue and the inner wall at the upper end of the boiler are provided with refractory materials having convex and concave portions on their opposing surfaces separated by a gap.

4. 3. The expansion structure for absorbing furnace thermal expansion and contraction according to claim 2, wherein the jaw portion of the holding frame is detachable from the side plate portion.

5. 3. The expansion structure for absorbing furnace thermal expansion and contraction according to claim 2, wherein the sealing material is a heat insulating blanket covered with a heat resistant cloth.

6. 3. An expansion structure for absorbing furnace thermal expansion and contraction according to claim 2, further comprising a rainwater protection section having an L-shaped cross section and covering at least the top plate section of the retaining frame on the extension of the flange.

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