High-temperature-resistant boiler slag discharge pipe

Abstract

The utility model relates to a boiler field, more specifically, relate to a kind of high-temperature-resistant boiler deslagging pipe. Including deslagging pipe, outer sleeve pipe, heat insulation layer, limit stop block system, intelligent detector and bevel deslagging end, deslagging pipe is the core internal pipeline of boiler deslagging, outer sleeve pipe coaxially is set in the outside of deslagging pipe, and annular gap is formed between the two, bevel deslagging end is set in the bottom outlet of deslagging pipe, and it is extended outer sleeve pipe downward, heat insulation layer is filled in annular gap, limit stop block system is installed in annular gap, and it is embedded in heat insulation layer, its inside and deslagging pipe outer wall are connected, outside and the inner wall of outer sleeve pipe are connected, intelligent detector sensor head is set in the outer wall of deslagging pipe, and located the inside of heat insulation layer. The device is synergistically improved the anti-blocking performance of deslagging pipe, high-temperature structural stability, thermal stress adaptability and overall service life through the above multilevel, integrated structural innovation. The utility model is mainly applied to the aspect of boiler deslagging.

Description

Technical Field

[0001] This utility model relates to the field of boilers, and more specifically, to a high-temperature resistant boiler slag discharge pipe. Background Technology

[0002] In the field of boiler equipment technology, slag discharge pipes are key components responsible for the transportation and discharge of high-temperature slag. However, with the continuous improvement of boiler operating parameters, especially the widespread application of high-efficiency boilers such as circulating fluidized bed boilers, the thermal load, mechanical load, and slag impact conditions faced by the slag discharge system are becoming increasingly severe, placing higher demands on the high-temperature resistance, structural integrity, and long-term operational reliability of the slag discharge pipes.

[0003] Currently, a common core problem in the industry is that ash discharge ports are easily blocked by large pieces of slag or detached refractory castable, severely affecting the continuity of ash discharge and leading to decreased boiler efficiency or even unplanned shutdowns. Furthermore, traditional ash discharge pipes are mostly manufactured in sections and assembled by welding. Under high temperatures and thermal cycling, stress concentration easily occurs at the weld joints, leading to cracks or fractures. Simultaneously, there is a significant temperature difference between the inner and outer walls of the ash discharge pipe. The high-temperature slag flow inside raises the pipe wall temperature to several hundred degrees Celsius. When the external environment or cooling conditions are insufficient, the thermal stress caused by the temperature difference can lead to pipe deformation, accelerated creep, and even rupture, seriously threatening system safety. While existing solutions attempt to alleviate these problems by optimizing materials, adding insulation, or improving supports, significant shortcomings remain. For example, the flat-mouth slag discharge design cannot effectively guide slag blocks, easily leading to blockages; the segmented tube structure introduces multiple weld joints, becoming weak points in the structure; conventional limiting devices mostly use fixed supports, restricting the freedom of thermal expansion of the tube body and increasing friction and wear between it and the outer casing; the insulation measures are simplistic, lacking an active cooling mechanism, making it difficult to control the temperature difference within a safe range. These pain points not only increase maintenance frequency and costs but also restrict the overall operating efficiency of the boiler. Utility Model Content

[0004] To overcome the shortcomings of the existing technology, this utility model provides a high-temperature resistant boiler slag discharge pipe. This slag discharge pipe provides a slag discharge pipe system with anti-clogging oblique openings, an integral high-temperature resistant pipe body, integrated high-efficiency heat insulation and cooling, low-friction limiting support, and intelligent monitoring functions. This significantly improves its reliability, durability, and ease of maintenance under high-temperature and high-wear conditions, meeting the urgent needs of modern boiler equipment for efficient and stable slag discharge.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows: A high-temperature resistant boiler ash discharge pipe includes an ash discharge pipe, an outer sleeve, a heat insulation layer, a limiting block system, an intelligent detector, an inclined ash discharge end, and an air-cooling channel. The outer sleeve is coaxially sleeved outside the ash discharge pipe, forming an annular gap between the ash discharge pipe and the outer sleeve. The inclined ash discharge end is located at the bottom outlet of the ash discharge pipe and extends downwards out of the outer sleeve. The heat insulation layer fills the annular gap. The limiting block system is installed between the ash discharge pipe and the outer sleeve and embedded in the heat insulation layer. The inner side of the limiting block system is connected to the outer wall of the ash discharge pipe, and the outer side is connected to the inner wall of the outer sleeve. The sensing head of the intelligent detector is located on the inner side of the outer sleeve of the outer sleeve and does not contact the outer sleeve. The air-cooling channel is located on the outer wall of the outer sleeve.

[0006] The slag discharge pipe is an integral bimetallic composite pipe. Its pipe wall consists of a wear-resistant and corrosion-resistant inner lining and an outer layer that provides structural strength, from the inside out. The inner lining is made of high-chromium cast iron, and the outer layer is made of austenitic stainless steel.

[0007] The slag discharge end of the pipe is cut into a 30° to 45° bevel to form a bevel structure, and the surface of the bevel structure is sprayed with a tungsten carbide wear-resistant coating.

[0008] The limiting block system includes a bracket and a roller. The bracket is disposed on the outer wall of the slag discharge pipe, and the roller is disposed on the bracket via a rotating shaft. The roller makes rolling contact with the inner wall of the outer sleeve.

[0009] The insulation layer is filled with ceramic fiber material, and the outer tube has an integrated annular air-cooling channel on its wall. The inlet and outlet of the air-cooling channel are used to connect to the boiler's primary air system.

[0010] The intelligent detector is a high-temperature thermocouple embedded in the outer wall of the slag discharge pipe, and the signal output end of the high-temperature thermocouple is connected to the boiler control system.

[0011] The slag discharge pipe, the heat insulation layer, and the outer jacket are arranged coaxially from the inside to the outside, forming a multi-layered composite tubular structure.

[0012] Compared with the prior art, the beneficial effects of this utility model are as follows: Structurally, the slag discharge pipe has been optimized from a segmented design to a monolithic structure, fundamentally eliminating structural weaknesses caused by welded joints and significantly improving the pipe's structural integrity and load-bearing capacity under high-temperature conditions. The coaxial outer sleeve design, together with the internal slag discharge pipe, forms an effective double-layer protection system. In key structural areas, the slag discharge port has been improved to a beveled structure at a specific angle, supplemented by a flow guide channel design. This structure effectively alters the flow path and direction of the slag, greatly reducing the risk of large slag blocks or foreign objects accumulating and covering the discharge port, ensuring a continuous and smooth slag discharge process.

[0013] An innovative system of limiting blocks and a thermal insulation layer is integrated within the annular gap between the slag discharge pipe and the outer casing. The limiting blocks employ a rolling contact support method, providing necessary radial positioning and support for the internal slag discharge pipe while transforming the solid friction between it and the outer casing into rolling friction. This ensures structural stability while allowing the slag discharge pipe to freely expand and contract axially under thermal expansion, effectively releasing thermal stress. Simultaneously, the filled ceramic fiber insulation layer and the air-cooling channel integrated into the outer casing together constitute a highly efficient composite thermal management system. This system effectively controls the temperature difference within the slag discharge pipe wall within a safe range, fundamentally suppressing deformation, creep, and fracture caused by excessive temperature differences.

[0014] At the material structure level, the slag discharge pipe adopts a bimetallic composite structure, with an inner lining of high-chromium cast iron and an outer layer of austenitic stainless steel, each leveraging their respective advantages in wear resistance, corrosion resistance, and high strength. Wear-resistant coatings are sprayed onto key wear areas such as the beveled edges, forming a tiered material protection system. An intelligent monitoring structure embedded in the pipe wall provides the hardware foundation for condition monitoring and predictive maintenance. Through these multi-layered, integrated structural innovations, this device synergistically improves the slag discharge pipe's anti-clogging performance, high-temperature structural stability, thermal stress adaptability, and overall service life, significantly enhancing operational reliability and ease of maintenance. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the overall assembly of the present utility model; Figure 2 This is a schematic diagram of the structure of this utility model from another angle; Figure 3 This is a schematic cross-sectional view of the structure of this utility model; Figure 4 This is a schematic diagram of the limiting block system of this utility model; In the diagram: 1 is the slag discharge pipe, 2 is the outer casing, 3 is the insulation layer, 4 is the limit block system, 41 is the support, 42 is the roller, 5 is the intelligent detector, 6 is the inclined slag discharge end, and 7 is the air-cooling channel. Detailed Implementation

[0016] To better understand the above-mentioned objectives, features, and advantages of this utility model, the present utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0017] Many specific details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the scope of protection of the present invention is not limited to the specific embodiments disclosed below.

[0018] like Figures 1 to 4 As shown, a high-temperature resistant boiler ash discharge pipe includes an ash discharge pipe 1, an outer sleeve 2, a heat insulation layer 3, a limiting block system 4, an intelligent detector 5, an inclined ash discharge end 6, and an air-cooling channel 7. The outer sleeve 2 is coaxially sleeved outside the ash discharge pipe 1, forming an annular gap between the ash discharge pipe 1 and the outer sleeve 2. The inclined ash discharge end 6 is located at the bottom outlet of the ash discharge pipe 1 and extends downwards out of the outer sleeve 2. The heat insulation layer 3 fills the annular gap. The limiting block system 4 is installed between the ash discharge pipe 1 and the outer sleeve 2 and is embedded in the heat insulation layer 3. The inner side of the limiting block system 4 is connected to the outer wall of the ash discharge pipe 1. The outer side is connected to the inner wall of the outer sleeve 2. The sensor head of the intelligent detector 5 is set on the inner side of the outer sleeve 2 of the outer wall of the slag discharge pipe 1, and does not contact the outer sleeve 2. The air-cooling channel 7 is set on the outer wall of the outer sleeve 2. The slag discharge pipe 1 is hoisted into place, and then the outer sleeve 2 is coaxially fitted on it, ensuring that the inclined slag discharge end 6 extends out of the bottom of the outer sleeve 2. The limiting block system 4 is installed in the annular gap and connected to the inner and outer pipe walls. Then, the heat insulation layer 3 material is filled to fill the gap and wrap the limiting block system 4. The sensor head of the intelligent detector 5 is fixed at the designated position on the outer wall of the slag discharge pipe 1 and the lead wire is connected.

[0019] Preferably, the slag discharge pipe 1 is an integral bimetallic composite pipe with a wall consisting of a wear-resistant and corrosion-resistant inner lining and an outer layer that provides structural strength. The inner lining is made of high-chromium cast iron, and the outer layer is made of austenitic stainless steel. The slag discharge pipe 1 is manufactured using a centrifugal casting process. First, the high-chromium cast iron lining is cast to form the inner layer. Then, the outer layer of austenitic stainless steel pipe blank is wrapped with it through metallurgical bonding. Finally, it is cold-rolled or stretched into an integral pipe without longitudinal weld seams, thus possessing both high wear resistance and high structural strength.

[0020] Preferably, the pipe opening of the slag discharge end 6 is cut into a 30° to 45° bevel to form a bevel structure. The surface of the bevel structure is sprayed with a tungsten carbide wear-resistant coating. After the slag discharge pipe 1 is integrally formed, its bottom port is cut into a 30° to 45° bevel using a plasma cutting device. After cutting, the bevel surface is roughened by sandblasting, and then a dense tungsten carbide coating is sprayed onto the bevel surface to significantly enhance its wear resistance.

[0021] Preferably, the limiting block system 4 includes a bracket 41 and a roller 42. The bracket 41 is disposed on the outer wall of the slag discharge pipe 1, and the roller 42 is disposed on the bracket 41 through a rotating shaft. The roller 42 rolls in contact with the inner wall of the outer sleeve 2. First, the bracket 41 is welded and fixed at multiple positions evenly distributed around the outer wall of the slag discharge pipe 1. The roller 42 with built-in high-temperature bearing is installed on the lug of the bracket 41 through a pin shaft to ensure that the roller 42 can rotate flexibly.

[0022] Preferably, the insulation layer 3 is filled with ceramic fiber material, and the outer tube 2 has an integrated annular air-cooling channel 7 on its tube wall. The inlet and outlet of the air-cooling channel 7 are used to connect to the boiler primary air system. The insulation layer 3 is filled with ceramic fiber blanket. During construction, it needs to be filled and compacted in layers. During manufacturing, the outer tube 2 is formed by welding a special profile around its tube wall to form the annular air-cooling channel 7.

[0023] Preferably, the intelligent detector 5 is a high-temperature thermocouple embedded in the outer wall of the slag discharge pipe 1. The signal output end of the high-temperature thermocouple is connected to the boiler control system. An installation hole is opened at a designated position on the outer wall of the slag discharge pipe 1, the temperature measuring end of the high-temperature thermocouple is inserted and sealed and fixed by welding. Its compensation wire is laid along the pipe wall, passes through the insulation layer 3 and the outer sleeve 2, and is connected to the system in the boiler main control room to realize real-time temperature monitoring and over-limit alarm.

[0024] Preferably, the slag discharge pipe 1, the heat insulation layer 3, and the outer sleeve 2 are arranged coaxially from the inside to the outside, forming a multi-layer composite tubular structure. With the slag discharge pipe 1 as the axis, the limiting block system 4 is installed, the heat insulation layer 3 is filled, and the outer sleeve 2 is coaxially fitted. All components ultimately form a stable multi-layer composite tubular structure.

[0025] Prepare the core component, the slag discharge pipe 1. This slag discharge pipe 1 is a monolithically manufactured bimetallic composite pipe, with an inner layer of high-chromium cast iron and an outer layer of austenitic stainless steel. Inspect the pipe body and the specially designed beveled slag discharge end 6 to ensure that the bevel cutting angle is correct and the tungsten carbide coating on the surface is uniform and intact. Weld and fix multiple limit stop systems 4 to the predetermined positions on the outer wall of the slag discharge pipe 1 via their brackets 41. The rollers 42 on each limit stop system 4 should rotate flexibly, which is crucial to ensure free rolling later. Embed and fix the sensor head of the intelligent detector 5 to the designated position on the outer wall of the slag discharge pipe 1. Its signal cable needs to be temporarily fixed along the pipe wall, leaving sufficient length for later connection to the external control system.

[0026] After preparation, begin assembling the outer sleeve 2. Slowly and coaxially fit the outer sleeve 2 onto the outside of the ash discharge pipe 1, which has already been fitted with the limit stop system 4 and the intelligent detector 5. During this process, ensure that the ash discharge pipe 1 is centered on the outer sleeve 2, that the annular gap is uniform, and that the rollers 42 of the limit stop system 4 are in good contact with the inner wall of the outer sleeve 2. After the relative positions of the ash discharge pipe 1 and the outer sleeve 2 are adjusted and temporarily fixed, evenly fill the annular gap between them with the ceramic fiber insulation layer 3. Ensure the filling is compacted, while taking care to avoid damaging the cables of the installed limit stop system 4 and the intelligent detector 5. Connect the inlet and outlet of the air-cooled channel 7 integrated on the wall of the outer sleeve 2 to the primary air system piping of the boiler. Finally, hoist the assembled multi-layer composite tubular structure to the preset position at the bottom of the boiler. After fixing the outer sleeve 2, connect the signal output terminal of the intelligent detector 5 to the boiler control system, completing the entire installation and wiring process.

[0027] The above description only details the preferred embodiments of the present utility model. However, the present utility model is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present utility model, and all such changes should be included within the protection scope of the present utility model.

Claims

1. A high-temperature resistant boiler slag discharge pipe, characterized in that: The system includes a slag discharge pipe (1), an outer sleeve (2), a heat insulation layer (3), a limiting block system (4), an intelligent detector (5), an inclined slag discharge end (6), and an air-cooling channel (7). The outer sleeve (2) is coaxially sleeved outside the slag discharge pipe (1), forming an annular gap between the slag discharge pipe (1) and the outer sleeve (2). The inclined slag discharge end (6) is located at the bottom outlet of the slag discharge pipe (1) and extends downwards out of the outer sleeve (2). The heat insulation layer (3) fills the gap between the outer sleeve and the slag discharge pipe (1). The limiting block system (4) is installed between the slag discharge pipe (1) and the outer sleeve (2) and embedded in the heat insulation layer (3). The inner side of the limiting block system (4) is connected to the outer wall of the slag discharge pipe (1), and the outer side is connected to the inner wall of the outer sleeve (2). The sensing head of the intelligent detector (5) is set on the outer wall of the slag discharge pipe (1) and does not contact the outer sleeve (2). The air-cooling channel (7) is set on the outer wall of the outer sleeve (2).

2. The high-temperature resistant boiler slag discharge pipe according to claim 1, characterized in that: The slag discharge pipe (1) is an integral bimetallic composite pipe. Its pipe wall consists of a wear-resistant and corrosion-resistant inner lining and an outer layer that provides structural strength, from the inside to the outside. The inner lining is made of high-chromium cast iron and the outer layer is made of austenitic stainless steel.

3. The high-temperature resistant boiler slag discharge pipe according to claim 1, characterized in that: The pipe opening of the slag discharge end (6) is cut into a 30° to 45° bevel to form a bevel structure, and the surface of the bevel structure is sprayed with a tungsten carbide wear-resistant coating.

4. The high-temperature resistant boiler slag discharge pipe according to claim 1, characterized in that: The limiting block system (4) includes a bracket (41) and a roller (42). The bracket (41) is disposed on the outer wall of the slag discharge pipe (1), and the roller (42) is disposed on the bracket (41) via a rotating shaft. The roller (42) makes rolling contact with the inner wall of the outer sleeve pipe (2).

5. A high-temperature resistant boiler slag discharge pipe according to claim 1, characterized in that: The insulation layer (3) is filled with ceramic fiber material, and the outer sleeve (2) has an integrated annular air-cooling channel (7) on its wall. The inlet and outlet of the air-cooling channel (7) are used to connect to the boiler primary air system.

6. The high-temperature resistant boiler slag discharge pipe according to claim 1, characterized in that: The intelligent detector (5) is a high-temperature thermocouple embedded in the outer wall of the slag pipe (1), and the signal output end of the high-temperature thermocouple is connected to the boiler control system.

7. A high-temperature resistant boiler slag discharge pipe according to claim 1, characterized in that: The slag discharge pipe (1), the heat insulation layer (3) and the outer jacket pipe (2) are arranged coaxially from the inside to the outside, forming a multi-layer composite tubular structure.

Images