Through-wall pipe heat preservation sealing structure
By setting a combined structure of inner expansion joints and outer expansion joints on the inner and outer sides of the through-wall pipe, the flue gas leakage caused by insufficient thermal expansion of the expansion joints and the over-temperature problems of wall-through areas are solved, achieving a more stable insulation and sealing effect and safer boiler operation.
Patent Information
- Application Number
- CN202510374881.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-27
- Publication Date
- 2025-06-17
AI Technical Summary
In the existing thermal insulation and sealing structure of the wall-through pipe, the thermal expansion of the expansion joints is insufficient, which causes the corrugated pipe to be easily deformed and cracked, causing flue gas leakage and overheating of the wall-through area, which poses safety risks.
The combined structure of inner expansion joint and outer expansion joint is adopted. The inner expansion joint is composed of a metal insulation box, corrugated pipe and slip ring. Through the sliding connection between the sliding ring and the metal insulation box, the wall pipe can stretch or compress the corrugated pipe to release the thermal expansion displacement; the outer expansion joint adopts non-metallic expansion joints, which are sealed between the furnace wall flange, outer flange and skin to achieve the release of thermal expansion displacement.
It effectively increases the compensation amount of expansion joints in the wall-through area, solves the problem of insufficient thermal expansion, ensures the stability and reliability of insulation and sealing performance, avoids flue gas leakage and over-temperature in the wall-through area, and reduces the safety risks of boiler operation.
Smart Images
Figure CN120160001A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a thermal insulation and sealing structure for a wall-piercing pipe, belonging to the technical field of boiler equipment. Background Art
[0002] A waste heat boiler generally has a multi-pressure working medium system, and the pipeline system is complexly arranged. It is generally necessary for the connecting pipes of the heating surface to penetrate through the boiler flue. In order to prevent flue gas leakage and heat loss of the working medium inside the wall-piercing pipe, a thermal insulation and sealing structure needs to be provided at the part where the wall-piercing pipe passes through the furnace wall panel. Due to the thermal expansion and contraction of the heating surface pipes caused by the start-up and shutdown of the boiler, thermal expansion displacement will occur in the wall-piercing pipe. Therefore, an expansion joint needs to be configured in the thermal insulation and sealing structure at the wall-piercing part to release the thermal expansion displacement of the wall-piercing pipe through the expansion joint. The expansion joint usually adopts a metal bellows. The existing thermal insulation and sealing structure for wall-piercing pipes often has the following defects in actual use: due to the frequent start-up and shutdown of power station boilers and the large thermal expansion displacement of the wall-piercing pipes in the high-temperature area, and the insufficient thermal expansion of the expansion joint, the bellows are prone to deformation and cracking, resulting in flue gas leakage and overheating at the wall-piercing part, bringing certain risks to the safe and stable operation of the unit. Summary of the Invention
[0003] The present invention mainly solves the technical problem that the insufficient thermal expansion of the expansion joint in the prior art leads to easy deformation and cracking of the bellows, resulting in flue gas leakage and overheating at the wall-piercing part, and provides a thermal insulation and sealing structure for a wall-piercing pipe with sufficient thermal expansion and stable and reliable thermal insulation and sealing performance.
[0004] The present invention mainly solves the above technical problems through the following technical solutions: The present invention includes a wall-piercing pipe passing through the furnace wall panel at a through hole, and an expansion joint sleeved on the wall-piercing pipe. The expansion joint is characterized in that it includes an inner expansion joint installed on one side inside the furnace and an outer expansion joint installed on one side outside the furnace. The inner expansion joint and the outer expansion joint respectively cover the through hole on the inner and outer sides of the furnace wall panel and are used to release the thermal expansion displacement of the wall-piercing pipe; The inner expansion joint includes a metal heat preservation box sleeved on the outside of the wall-piercing pipe, a bellows sleeved on the wall-piercing pipe inside the metal heat preservation box, a slip ring sealingly and fixedly connected to the wall-piercing pipe. One end of the metal heat preservation box is sealingly and fixedly connected to the furnace wall panel on the outer periphery of the through hole, and the end far from the furnace wall panel is provided with a slip hole matching the outer diameter of the slip ring. One end of the bellows is fixedly connected to the metal heat preservation box, and the other end is fixedly connected to the slip ring. The slip ring forms a sliding connection with the metal heat preservation box in the slip hole. When the wall-piercing pipe generates thermal expansion displacement, the bellows is stretched or compressed through the slip ring.
[0005] Preferably, the outer expansion joint includes a furnace wall flange covering the through hole and sealingly and fixedly connected to the furnace wall panel, an outer side flange sealingly and fixedly connected to the wall-piercing pipe. The furnace wall flange and the outer side flange are sealingly connected through a skin, and the wall-piercing pipe can drive the outer side flange to move relatively away from or close to the furnace wall flange.
[0006] Preferably, a first heat insulation pillow is filled in the gap between the furnace wall flange and the outer wall of the through-wall pipe. In the cavity between the skin and the outer wall of the through-wall pipe, there are a second heat insulation pillow wrapping the through-wall pipe and a third heat insulation pillow wrapping the outside of the second heat insulation pillow.
[0007] Preferably, the skin is fixed to the outer circumferential surfaces of the furnace wall flange and the outer flange by clamps.
[0008] Preferably, it further includes a U-shaped steel hook disposed between the second heat insulation pillow and the third heat insulation pillow for hooking the third heat insulation pillow. The U-shaped steel hook is fixedly connected to the furnace wall flange through a connecting member.
[0009] Preferably, the second heat insulation pillow and the third heat insulation pillow are fixed by steel belts.
[0010] The structure of the present invention is simple, reasonably configured and has the following advantages: In the present invention, an inner expansion joint and an outer expansion joint are sleeved on the through-wall pipe. The inner expansion joint and the outer expansion joint release the thermal expansion displacement of the through-wall pipe on both sides inside and outside the furnace, so as to increase the compensation amount of the expansion joint at the through-wall part and solve the problem of insufficient thermal expansion. The inner expansion joint and the outer expansion joint cover the through holes on the furnace wall panel, which can prevent flue gas leakage at the through holes to meet the sealing requirements of the through-wall structure. Among them, the inner expansion joint is composed of a corrugated pipe sleeved on the through-wall pipe, a metal heat preservation box surrounding the corrugated pipe and covering the through hole on the furnace wall panel, and a sliding ring slidably connected to the metal heat preservation box. The sliding ring is fixed to the through-wall pipe, and the through-wall pipe can stretch or compress the corrugated pipe through the sliding ring to release the thermal expansion displacement. In the inner expansion joint, the metal heat preservation box is used to block the flue gas, avoid the direct scouring of the high-temperature flue gas on the corrugated pipe and prevent flue gas leakage at the through hole position of the furnace wall panel. The sliding connection is adopted between the sliding ring and the metal heat preservation box, and the through-wall pipe generates relative sliding with the metal heat preservation box through the sliding ring, so that the thermal expansion displacement can be released more smoothly. At the same time, this sliding connection also has a sealing function and can prevent the flue gas from entering the metal heat preservation box through the connection part between the sliding ring and the metal heat preservation box.
[0011] Further, the outer expansion joint adopts a non-metallic expansion joint and includes a furnace wall flange and an outer flange. The through-wall pipe releases its thermal expansion displacement on the outside of the furnace by driving the outer flange to move relatively close to or away from the furnace wall flange. The furnace wall flange is hermetically connected to the furnace wall panel, the outer flange is hermetically fixed to the through-wall pipe, and the furnace wall flange and the outer flange are hermetically connected by a telescopic skin to form a closed sealing structure, which can effectively prevent flue gas leakage at the through hole and further improve the sealing effect of the through-wall structure.
[0012] Further, the outer expansion joint is filled with a first heat insulation pillow, a second heat insulation pillow and a third heat insulation pillow. The heat insulation effect can be enhanced through multi-layer heat insulation, and the heat loss of the working medium in the through-wall pipe can be effectively prevented.
[0013] Furthermore, the skin is fixed by a clamp, which is simple and firm, and it is relatively convenient to disassemble and replace the skin.
[0014] Furthermore, a U-shaped steel hook is arranged between the second heat insulation pillow and the third heat insulation pillow. The third heat insulation pillow is hooked by the U-shaped steel hook to prevent it from slipping, thereby avoiding the formation of a cavity due to the separation of the third heat insulation pillow from the first heat insulation pillow above, which affects the heat preservation effect.
[0015] Furthermore, by bundling with steel belts, the second heat insulation pillow and the third heat insulation pillow can be fixed more tightly to the wall-piercing pipe.
[0016] Therefore, the present invention has the advantages of stable and reliable structure, sufficient thermal expansion, and good heat preservation and sealing effects, avoiding smoke leakage and overheating at the wall-piercing part, and reducing the safety risks during the operation of the boiler. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Attached Figure 1 is a schematic diagram of a preferred embodiment of the present invention.
[0018] Attached Figure 2 is a schematic diagram of the outer expansion joint in a preferred embodiment of the present invention.
[0019] Description of the reference numerals: 1. furnace wall panel; 11. through hole; 2. wall-piercing pipe; 3. inner expansion joint; 31. metal heat preservation box; 311. sliding hole; 32. corrugated pipe; 33. sliding ring; 4. outer expansion joint; 41. furnace wall flange; 42. outer flange; 43. skin; 44. first heat insulation pillow; 45. second heat insulation pillow; 46. third heat insulation pillow; 47. clamp; 48. U-shaped steel hook; 49. steel belt. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0020] The technical solutions of the present invention will be further specifically described below through embodiments in combination with the drawings.
[0021] Embodiment 1: As shown in Attached Figure 1 and Attached Figure 2 , the present invention includes a wall-piercing pipe 2 passing through the furnace wall panel 1 at the through hole 11, an inner expansion joint 3 and an outer expansion joint 4 sleeved on the wall-piercing pipe 2. The inner expansion joint 3 and the outer expansion joint 4 respectively cover the through hole 11 on the inner and outer sides of the furnace wall panel 1 and are used to release the thermal expansion displacement of the wall-piercing pipe 2; The inner expansion joint 3 includes a metal heat preservation box 31 sleeved outside the wall-piercing pipe 2, a corrugated pipe 32 arranged in the inner cavity of the metal heat preservation box 31 and sleeved outside the wall-piercing pipe 2, and a sliding ring 33 with one end sealed and fixedly connected to the wall-piercing pipe 2 and the other end extending into the inner cavity of the metal heat preservation box 31. The wall-piercing pipe 2 releases the thermal expansion displacement through the relative sliding of the sliding ring 33 and the metal heat preservation box 31 on the inner side of the furnace; One end of the metal heat preservation box 31 is fixedly connected to the furnace wall panel 1 in a sealed manner on the outer periphery of the through hole 11, and a sliding hole 311 matching the outer diameter of the slip ring 33 is provided at the end far from the furnace wall panel; One end of the corrugated pipe 32 is fixedly connected to the metal heat preservation box 31, and the other end is fixedly connected to the slip ring 33. The wall thickness of the corrugated pipe 32 is 1 mm; The slip ring 33 is slidably connected to the metal heat preservation box 31 in the sliding hole 311. When the slip ring 33 slides along the sliding hole 311 with the through-wall pipe 2, the corrugated pipe 32 is stretched or compressed; The outer expansion joint 4 includes a furnace wall flange 41 fixedly connected to the furnace wall panel 1 in a sealed manner on the outer periphery of the through hole 11, an outer flange 42 fixedly connected to the through-wall pipe 2 in a sealed manner. The furnace wall flange 41 and the outer flange 42 are sealed and connected by a skin 43. The through-wall pipe 2 releases the thermal expansion displacement by driving the outer flange 42 to move away from or close to the furnace wall flange 41 on the outside of the furnace; The space between the furnace wall flange 41 and the outer wall of the through-wall pipe 2 is filled with a first heat insulation pillow 44, and the space between the skin 43 and the outer wall of the through-wall pipe 2 is filled with a second heat insulation pillow 45 and a third heat insulation pillow 46; The skin 43 is fixed between the furnace wall flange 41 and the outer flange 42 by a clamp 47; The second heat insulation pillow 45 wraps the through-wall pipe 2 and is bound by a steel strip 49; The third heat insulation pillow 46 wraps the second heat insulation pillow 45 and is bound by a steel strip 49; The U-shaped steel hook 48 is fixedly connected to the outer flange 42 through a connecting piece and hooks the third heat insulation pillow 46.
[0022] Of course, the above-mentioned drawings and embodiments are only used to explain and illustrate the present invention and cannot be used as an improper limitation of the present invention. All technical solutions obtained by those skilled in the art through equivalent adjustments and changes based on the present invention fall within the protection scope of the present invention.
Claims
1. A through-wall pipe thermal insulation sealing structure, comprising a through-wall pipe (2) passing through a furnace wall plate (1) at a through hole (11), and an expansion joint sleeved on the through-wall pipe (2), characterized in that: The expansion joint comprises an inner expansion joint (3) installed on one side inside the furnace and an outer expansion joint (4) installed on one side outside the furnace, the inner expansion joint (3) and the outer expansion joint (4) respectively covering the through hole (11) on the inner and outer sides of the furnace wall plate (1) and used to release the thermal expansion displacement of the through-wall pipe (2); The inner expansion joint (3) comprises a metal insulation box (31) sleeved on the outside of the through-wall pipe (2), a bellows (32) sleeved on the through-wall pipe (2) inside the metal insulation box (31), and a slip ring (33) sealed and fixedly connected to the through-wall pipe (2); one end of the metal insulation box (31) is sealed and fixedly connected to the furnace wall plate (1) at the periphery of the through hole (11), and a sliding hole (311) matching the outer diameter of the slip ring (33) is provided at one end away from the furnace wall plate (1); one end of the bellows (32) is fixedly connected to the metal insulation box (31) and the other end is fixedly connected to the slip ring (33); the slip ring (33) forms a sliding connection with the metal insulation box (31) at the sliding hole (311); when the through-wall pipe (2) generates thermal expansion displacement, the bellows (32) is stretched or compressed through the slip ring (33).
2. A wall-penetrating pipe thermal insulation sealing structure according to claim 1, characterized in that: The external expansion joint (4) comprises a furnace wall flange (41) covering the through hole (11) and being sealed and fixedly connected to the furnace wall plate (1), and an outer flange (42) being sealed and fixedly connected to the through-wall pipe (2). The furnace wall flange (41) and the outer flange (42) are sealedly connected via a covering (43), and the through-wall pipe (2) can drive the outer flange (42) to move relative to or away from the furnace wall flange (41).
3. A wall-penetrating pipe thermal insulation sealing structure according to claim 2, characterized in that: The gap between the furnace wall flange (41) and the outer wall of the through-wall pipe (2) is filled with a No. 1 insulation pillow (44), and the cavity between the skin (43) and the outer wall of the through-wall pipe (2) is provided with a No. 2 insulation pillow (45) wrapping the through-wall pipe (2) and a No. 3 insulation pillow (46) wrapping the outside of the No. 2 insulation pillow (45).
4. A wall-penetrating pipe insulation sealing structure according to claim 2, characterized in that: The skin (43) is fixed to the outer peripheral surfaces of the furnace wall flange (41) and the outer flange (42) via a clamp (47).
5. A wall-penetrating pipe insulation sealing structure according to claim 3, characterized in that: It also includes a U-shaped steel hook (48) arranged between the No. 2 insulation pillow (45) and the No. 3 insulation pillow (46) for hooking the No. 3 insulation pillow (46), and the U-shaped steel hook (48) is fixedly connected to the furnace wall flange (41) via a connecting piece.
6. A wall-penetrating pipe thermal insulation sealing structure according to claim 3, characterized in that: The No. 2 thermal insulation pillow (45) and the No. 3 thermal insulation pillow (46) are bound and fixed by a steel belt (49).