Dry quenching chamber outlet arch preassembly method

Abstract

The invention relates to the technical field of dry quenching processes, and particularly discloses a dry quenching chamber outlet arch pre-assembly method for dry quenching, which adopts a mullite brick layer and staggered slab brick layer composite masonry process, and specifically comprises the following steps: S1, pre-assembly early-stage preparation and reference calibration; s2, reference masonry of a bottom mullite brick layer; S3, composite masonry and occlusion positioning of a slab staggering brick layer; s4, carrying out layered prepressing and defect detection; and S5, integrally fixing and transferring the identification. The pre-assembled arch body is remarkable in comprehensive performance, high in compressive strength at the temperature of 25 DEG C and high temperature, high in thermal shock resistance and low in high-temperature creep rate, preheating treatment of mullite bricks, a staggered slab brick concave-convex meshing structure and reasonable staggered joint arrangement are adopted, and a layered progressive increase pre-pressing mode from arch feet to an arch crown is matched, so that the attaching compactness and the structural stability of the brick body are improved. The arch body prepared by the method is high in high-temperature resistance, deformation resistance and thermal shock resistance, and can adapt to harsh working conditions of the dry quenching chamber, and the service life of the arch body is prolonged.

Description

Technical Field

[0001] This application relates to the field of dry quenching coke technology, and more specifically, it relates to a method for pre-assembling the arch at the outlet of the dry quenching chamber. Background Technology

[0002] Dry quenching technology, as an energy-saving and environmentally friendly coke cooling process, relies heavily on the dry quenching furnace, its core equipment, whose operational stability directly impacts production efficiency and safety. The outlet arch of the dry quenching chamber, a key load-bearing and airflow guiding component of the furnace's outer wall, is shaped like an arch bridge. It must conform to the curvature of the furnace's outer wall edge and meet the arch span requirements for the gas flow from the annular duct to the primary dust collector. Its assembly precision directly determines the subsequent gas flow efficiency and equipment sealing performance. This outlet arch is typically constructed of two layers: mullite bricks and staggered bricks, with an overall weight of approximately 18 tons. The large weight of each individual brick makes assembly extremely difficult.

[0003] Current pre-assembly processes generally use wooden jigs for positioning and support. To prevent the masonry from slipping at both ends, additional fixing tools are required at both ends of the jig, and a special tool platform needs to be built for laying the upper masonry. This not only makes the construction process complex and labor-intensive, but also results in high manufacturing costs because the wooden jigs must meet high-strength load-bearing requirements. Furthermore, wood is susceptible to deformation due to environmental humidity and temperature, making it difficult to accurately control the pre-assembly dimensions. Problems such as brick joint misalignment and arc deviation frequently occur, leading to insufficient sealing performance during on-site installation, increasing the risk of high-temperature gas leakage, and affecting the overall operational stability and service life of the dry quenching furnace. In addition, the poor foundation stability of wooden jigs makes them prone to collapse during high-altitude operations, posing a high safety risk. Therefore, there is an urgent need for a low-cost, high-precision, and high-safety pre-assembly method for the arch at the outlet of the dry quenching chamber to address the pain points of existing technologies. Summary of the Invention

[0004] To address the technical problems mentioned in the background art, this application provides a method for pre-assembling the arch at the outlet of the dry quenching chamber.

[0005] A pre-assembly method for the arch of the dry quenching chamber outlet is adopted, which uses a composite masonry process of mullite brick layer and staggered brick layer, specifically including the following steps: S1, pre-assembly preparation and benchmark calibration; S2, benchmark masonry of the bottom mullite brick layer; S3, composite masonry and interlocking positioning of staggered brick layer; S4, layered pre-compression and defect detection; S5, overall fixing and marking and transportation.

[0006] Preferably, in step S1, an arc-shaped pre-assembly platform matching the actual working conditions of the arch at the outlet of the quenching chamber is constructed. The surface of the platform is covered with a high-temperature resistant and anti-slip pad, and the bottom of the platform is equipped with a fine-adjustable lifting mechanism.

[0007] Preferably, the high-temperature resistant anti-slip pad has a Shore hardness of 65-75HA, a compressive strength of >15MPa at 25℃, a compressive strength retention rate of ≥80% at 300℃, and a friction coefficient of ≥0.8.

[0008] Preferably, in step S2, the mullite bricks need to be kept at 80-100℃ for 1.5-2 hours, heated to 150-200℃ at a heating rate of 1-3℃ / min, kept at 1-3℃ / min for 2-3 hours, and cooled to 120-140℃ at a cooling rate of 1-2℃ / min for 0.5-1 hours.

[0009] Preferably, in step S2, the bottom layer of mullite bricks is laid using a symmetrical method from the arch foot to the arch top, based on the masonry reference surface. Every 3-5 bricks are laid, the flatness of the brick layer is checked with a straightedge, and the flatness deviation does not exceed 0.4mm / m. After the masonry reaches the arch top, a temporary positioning reference pile is set at the center of the arch top. High-temperature refractory mortar is used to fill the gaps between adjacent mullite bricks, and the mortar thickness is controlled at 2-3mm.

[0010] Preferably, the high-temperature refractory slurry has a refractoriness >1750℃, a compressive strength at 25℃ >30MPa, and a high-temperature compressive strength >25MPa. The slurry needs to be stirred evenly during construction.

[0011] Preferably, in step S3, the overlapping surfaces of the staggered bricks are provided with a concave-convex interlocking structure that matches the mullite brick layer, and the concave-convex interlocking depth is 8-12mm.

[0012] Preferably, the center line of the staggered brick is staggered from the center line of the brick joint of the bottom mullite brick layer, and the stagger distance is 1 / 3 to 1 / 2 of the brick width. The radial displacement and circumferential curvature are calibrated by a laser positioning instrument after each layer of staggered bricks is laid.

[0013] Preferably, in step S4, the preloading pressure gradually increases from the arch foot to the arch crown. The specific increase method is as follows: starting from the arch foot, a reference preload of 0.3-0.5 MPa is applied first, and then pressure is applied in segments along the arch curvature towards the arch crown. The pressure gradient of each segment is controlled at 0.1-0.2 MPa, gradually transitioning to the arch crown area. Finally, the preloading pressure at the arch crown stabilizes at 0.8-1.0 MPa. The preloading time for each area of ​​the entire arch is controlled at 30-40 minutes. After the preloading is completed, an ultrasonic flaw detector is used to check the brick layer adhesion.

[0014] Preferably, in step S5, a detachable clamp is used to fix the arch as a whole, and a flexible protective pad is set at the contact part between the clamp and the brick. After the arch is divided into sections and numbered, it is horizontally transported to the storage area to avoid collision and vibration.

[0015] In summary, this application has the following beneficial effects: This application employs a gradient heating preheating treatment on mullite bricks, allowing for uniform moisture release from the brick body. This effectively eliminates internal stress generated during brick production and storage, preventing cracking and damage due to uneven thermal expansion and contraction during subsequent masonry and high-temperature conditions. Simultaneously, it improves the compatibility between the bricks and the high-temperature refractory mortar, laying a solid foundation for the quality of the underlying brick layers. By using a layered pre-compression treatment that gradually increases from the arch foot to the arch crown, the bonding between bricks and between mullite brick layers and staggered brick layers becomes denser. The filling high-temperature refractory mortar can fully penetrate the gaps, completely eliminating defects such as interlayer voids and loose brick joints. This significantly improves the compressive bearing capacity of the overall arch structure and effectively reduces the risk of high-temperature creep. By combining mullite gradient heating preheating, staggered brick interlocking structure masonry, and layered incremental preloading process, the arch body possesses both excellent structural stability and outstanding high-temperature adaptability. It can effectively resist the high-temperature erosion and frequent thermal shock at the outlet of the dry quenching chamber, and significantly improve the arch body's resistance to thermal shock and high-temperature compressive strength. Detailed Implementation

[0016] The present application will be further described in detail below with reference to the embodiments.

[0017] The mullite brick layer used in the embodiments and comparative examples of this invention was purchased from Zhengzhou Siji Huo Refractory Materials Co., Ltd.; the staggered brick was purchased from Zhengzhou Zhongjian Refractory Materials Co., Ltd.; the high-temperature resistant anti-slip pad layer was purchased from Dongguan Jinma Silicone Products Co., Ltd.; and the high-temperature refractory slurry was purchased from Gongyi Yuying Refractory Materials Co., Ltd.

[0018] Example 1 A method for pre-assembling the arch at the outlet of a dry quenching chamber, employing a composite masonry technique of mullite brick layers and staggered brick layers, specifically includes: S1. Pre-assembly Preparation and Benchmark Calibration: Construct an arc-shaped pre-assembly platform that matches the actual working conditions of the arch at the outlet of the quenching chamber. The platform surface is covered with a high-temperature resistant, anti-slip pad, and the bottom of the platform is equipped with a fine-tuning lifting mechanism to ensure that the platform's curvature and height can be adjusted as needed to meet the pre-assembly benchmark requirements. The high-temperature resistant, anti-slip pad must meet the following performance parameters: Shore hardness of 65HA, compressive strength at 25℃ > 15MPa, compressive strength retention rate at 300℃ ≥ 80%, and friction coefficient of the pad ≥ 0.8 to ensure the stability of the bricks during pre-assembly and prevent slippage or damage. S2. Baseline Construction of the Mullite Brick Layer: The mullite bricks need to be preheated. The preheating process parameters are as follows: hold at 80℃ for 1.5 hours, then heat to 150℃ at a rate of 1℃ / min and hold for 2 hours, then cool to 120℃ at a rate of 1℃ / min and hold for 0.5 hours. After preheating, allow to cool naturally to room temperature for later use. Using the base surface as a reference, lay the base layer of mullite bricks symmetrically from the arch foot to the arch crown. During the construction process, check the flatness of the brick layer with a straightedge every 3 bricks to ensure that the flatness deviation does not exceed 0.4mm / m. After reaching the arch crown, set a temporary positioning reference pile at the center of the arch crown to ensure the positioning accuracy of subsequent construction. High-temperature refractory mortar is used to fill the gaps between adjacent mullite bricks, and the mortar thickness is strictly controlled to 2mm. The high-temperature refractory mortar must meet the following performance requirements: refractoriness > 1750℃, compressive strength at 25℃ > 30MPa, and compressive strength at 300℃ > 25MPa. During construction, the mortar must be stirred evenly to ensure that it is filled densely without gaps.

[0019] S3. Composite Masonry and Interlocking Positioning of Staggered Brick Layers: After the bottom layer of mullite bricks is completed and passes inspection, the composite masonry of staggered brick layers is carried out. The overlapping surfaces of the staggered bricks are pre-set with a concave-convex interlocking structure that matches the mullite brick layer. The depth of the concave-convex interlocking is controlled at 8mm to ensure that the two layers of bricks can be tightly interlocked, thereby improving the overall structural stability. During masonry, the center line of the staggered bricks is staggered from the center line of the brick joint of the bottom layer of mullite bricks by 1 / 3 of the brick width, effectively preventing the brick joints of the upper and lower layers from being connected. After each layer of staggered bricks is laid, the radial displacement and circumferential curvature are immediately calibrated by a laser positioning instrument to ensure that the masonry accuracy of the staggered brick layer meets the design requirements.

[0020] S4. Layered Preloading and Defect Detection: The entire arch is subjected to layered preloading. The preloading pressure gradually increases from the arch foot to the arch crown. The specific increase method is as follows: Starting from the arch foot, a reference preloading pressure of 0.3 MPa is applied first. Then, pressure is applied in segments along the arch curvature towards the arch crown, with the pressure gradient of each segment controlled at 0.1 MPa, gradually transitioning to the arch crown area. Finally, the preloading pressure at the arch crown stabilizes at 0.8 MPa. The preloading time for each area of ​​the entire arch is controlled at 30 minutes. The deformation of the arch is monitored in real time during the preloading process. After the preloading is completed, an ultrasonic flaw detector is used to check the brick layer adhesion, focusing on the tightness of the adhesion between bricks and between brick layers. If defects such as substandard adhesion or gaps are found, the bricks must be demolished and rebuilt in a timely manner until the inspection is qualified.

[0021] S5. Overall Fixing and Marking for Transportation: After the defect inspection is passed, the arch is fixed as a whole using detachable clamps. Flexible protective pads are set at the contact points between the clamps and the bricks to prevent the clamps from damaging the brick surface. After fixing, the arch is marked with clear and accurate numbers to facilitate subsequent on-site installation and connection. Finally, the pre-assembled arch is horizontally transported to the storage area. Collisions and vibrations should be avoided during transportation. The storage area should be flat and dry, and protective measures should be taken to prevent the arch from getting damp or damaged.

[0022] Example 2 A method for pre-assembling the arch at the outlet of a dry quenching chamber, employing a composite masonry technique of mullite brick layers and staggered brick layers, specifically includes: S1. Pre-assembly Preparation and Benchmark Calibration: Construct an arc-shaped pre-assembly platform that matches the actual working conditions of the arch at the outlet of the quenching chamber. The platform surface is covered with a high-temperature resistant, anti-slip pad, and the bottom of the platform is equipped with a fine-tuning lifting mechanism to ensure that the platform's curvature and height can be adjusted as needed to meet the pre-assembly benchmark requirements. The high-temperature resistant, anti-slip pad must meet the following performance parameters: Shore hardness of 70HA, compressive strength at 25℃ > 15MPa, compressive strength retention rate at 300℃ ≥ 80%, and friction coefficient of the pad ≥ 0.8 to ensure the stability of the bricks during pre-assembly and prevent slippage or damage. S2. Baseline Construction of the Mullite Brick Layer: The mullite bricks need to be preheated. The preheating process parameters are as follows: hold at 90℃ for 1.8 hours, then heat to 180℃ at a rate of 2℃ / min and hold for 2.5 hours, then cool to 130℃ at a rate of 1.5℃ / min and hold for 0.8 hours. After preheating, allow to cool naturally to room temperature for later use. Using the base surface as a reference, lay the base layer of mullite bricks symmetrically from the arch foot to the arch crown. During the construction process, check the flatness of the brick layer with a straightedge every 4 bricks to ensure that the flatness deviation does not exceed 0.4mm / m. After reaching the arch crown, set a temporary positioning reference pile at the center of the arch crown to ensure the positioning accuracy of subsequent construction. High-temperature refractory mortar is used to fill the gaps between adjacent mullite bricks, and the mortar thickness is strictly controlled at 2.5mm. The high-temperature refractory mortar must meet the following performance requirements: refractoriness > 1750℃, compressive strength at 25℃ > 30MPa, and compressive strength at 300℃ > 25MPa. During construction, the mortar must be stirred evenly to ensure that it is filled densely without gaps.

[0023] S3. Composite Masonry and Interlocking Positioning of Staggered Brick Layers: After the bottom layer of mullite bricks is completed and passes inspection, the composite masonry of staggered brick layers is carried out. The overlapping surfaces of the staggered bricks are pre-set with a concave-convex interlocking structure that matches the mullite brick layer. The depth of the concave-convex interlocking is controlled at 10mm to ensure that the two layers of bricks can be tightly interlocked, thereby improving the overall structural stability. During masonry, the center line of the staggered bricks is staggered from the center line of the brick joint of the bottom layer of mullite bricks by 5 / 12 of the brick width, effectively preventing the brick joints of the upper and lower layers from being connected. After each layer of staggered bricks is laid, the radial displacement and circumferential curvature are immediately calibrated by a laser positioning instrument to ensure that the masonry accuracy of the staggered brick layer meets the design requirements.

[0024] S4. Layered Preloading and Defect Detection: The entire arch is subjected to layered preloading. The preloading pressure gradually increases from the arch foot to the arch crown. The specific increase method is as follows: Starting from the arch foot, a reference preloading pressure of 0.4 MPa is applied first. Then, pressure is applied in segments along the arch curvature towards the arch crown, with the pressure gradient of each segment controlled at 0.15 MPa, gradually transitioning to the arch crown area. Finally, the preloading pressure at the arch crown stabilizes at 0.9 MPa. The preloading time for each area of ​​the entire arch is controlled at 35 minutes. The deformation of the arch is monitored in real time during the preloading process. After the preloading is completed, an ultrasonic flaw detector is used to test the brick layer adhesion, focusing on the tightness of the adhesion between bricks and between brick layers. If defects such as substandard adhesion or gaps are found, the bricks must be demolished and rebuilt in a timely manner until the test is qualified.

[0025] S5. Overall Fixing and Identification During Transportation: After passing defect inspection, the arch is fixed as a whole using detachable clamps. Flexible protective pads are placed at the contact points between the clamps and the bricks to prevent damage to the brick surface. After fixing, the arch is divided into sections and labeled clearly and accurately for easy on-site installation and connection. Finally, the pre-assembled arch is horizontally transported to the storage area, avoiding collisions and vibrations during transportation. The storage area must be flat and dry, and protective measures must be taken to prevent the arch from getting damp or damaged.

[0026] Example 3 A method for pre-assembling the arch at the outlet of a dry quenching chamber, employing a composite masonry technique of mullite brick layers and staggered brick layers, specifically includes: S1. Pre-assembly Preparation and Benchmark Calibration: Construct an arc-shaped pre-assembly platform that matches the actual working conditions of the arch at the outlet of the quenching chamber. The platform surface is covered with a high-temperature resistant, anti-slip pad, and the bottom of the platform is equipped with a fine-adjustable lifting mechanism to ensure that the platform's curvature and height can be adjusted as needed to meet the pre-assembly benchmark requirements. The high-temperature resistant, anti-slip pad must meet the following performance parameters: Shore hardness of 75HA, compressive strength at 25℃ > 15MPa, compressive strength retention rate at 300℃ ≥ 80%, and friction coefficient of the pad ≥ 0.8 to ensure the stability of the bricks during pre-assembly and prevent slippage or damage. S2. Baseline Construction of the Mullite Brick Layer: The mullite bricks need to be preheated. The preheating process parameters are as follows: hold at 100℃ for 2 hours, then heat to 200℃ at a rate of 3℃ / min and hold for 3 hours, then cool to 140℃ at a rate of 2℃ / min and hold for 1 hour. After preheating, allow to cool naturally to room temperature for later use. Using the base surface as a reference, lay the base layer of mullite bricks symmetrically from the arch foot to the arch top. During the construction process, check the flatness of the brick layer with a straightedge every 5 bricks to ensure that the flatness deviation does not exceed 0.4mm / m. After reaching the arch top, set a temporary positioning reference pile at the center of the arch top to ensure the positioning accuracy of subsequent construction. High-temperature refractory mortar is used to fill the gaps between adjacent mullite bricks, and the mortar thickness is strictly controlled at 3mm. The high-temperature refractory mortar must meet the following performance requirements: refractoriness > 1750℃, compressive strength at 25℃ > 30MPa, and compressive strength at 300℃ > 25MPa. During construction, the mortar must be stirred evenly to ensure that it is filled densely without gaps.

[0027] S3. Composite Construction and Interlocking Positioning of Staggered Brick Layers: After the bottom layer of mullite bricks is completed and passes inspection, the composite construction of staggered brick layers is carried out. The overlapping surfaces of the staggered bricks are pre-set with a matching interlocking structure to the mullite brick layer, with the interlocking depth controlled at 12mm to ensure a tight interlock between the two layers, improving overall structural stability. During construction, the centerline of the staggered bricks is offset from the centerline of the brick joints in the bottom layer of mullite bricks by a distance equal to half the width of the brick, effectively preventing the joints from being continuous between the upper and lower layers. After each layer of staggered bricks is laid, the radial displacement and circumferential curvature are immediately calibrated using a laser positioning instrument to ensure that the construction accuracy of the staggered brick layer meets design requirements.

[0028] S4. Layered Preloading and Defect Detection: The entire arch is subjected to layered preloading. The preloading pressure gradually increases from the arch foot to the arch crown. The specific increase method is as follows: Starting from the arch foot, a reference preloading pressure of 0.5 MPa is applied first. Then, pressure is applied in segments along the arch curvature towards the arch crown, with the pressure gradient of each segment controlled at 0.2 MPa, gradually transitioning to the arch crown area. Finally, the preloading pressure at the arch crown stabilizes at 1.0 MPa. The preloading time for each area of ​​the entire arch is controlled at 40 minutes. The deformation of the arch is monitored in real time during the preloading process. After the preloading is completed, an ultrasonic flaw detector is used to check the brick layer adhesion, focusing on the tightness of the adhesion between bricks and between brick layers. If defects such as substandard adhesion or gaps are found, the bricks must be demolished and rebuilt in a timely manner until the inspection is qualified.

[0029] S5. Overall Fixing and Identification During Transportation: After passing defect inspection, the arch is fixed as a whole using detachable clamps. Flexible protective pads are placed at the contact points between the clamps and the bricks to prevent damage to the brick surface. After fixing, the arch is divided into sections and labeled clearly and accurately for easy on-site installation and connection. Finally, the pre-assembled arch is horizontally transported to the storage area, avoiding collisions and vibrations during transportation. The storage area must be flat and dry, and protective measures must be taken to prevent the arch from getting damp or damaged.

[0030] Comparative Example 1 A method for pre-assembling the arch at the outlet of a dry quenching chamber, employing a composite masonry technique of mullite brick layers and staggered brick layers, specifically includes: S1. Pre-assembly Preparation and Benchmark Calibration: Construct an arc-shaped pre-assembly platform that matches the actual working conditions of the arch at the outlet of the quenching chamber. The platform surface is covered with a high-temperature resistant, anti-slip pad, and the bottom of the platform is equipped with a fine-tuning lifting mechanism to ensure that the platform's curvature and height can be adjusted as needed to meet the pre-assembly benchmark requirements. The high-temperature resistant, anti-slip pad must meet the following performance parameters: Shore hardness of 65HA, compressive strength at 25℃ > 15MPa, compressive strength retention rate at 300℃ ≥ 80%, and friction coefficient of the pad ≥ 0.8 to ensure the stability of the bricks during pre-assembly and prevent slippage or damage. S2. Baseline Mullite Brick Laying: Using the base surface as a reference, the baseline mullite bricks are laid symmetrically from the arch foot to the arch crown. During construction, the flatness of the brick layer is checked with a straightedge every three bricks to ensure a flatness deviation of no more than 0.4 mm / m. After reaching the arch crown, a temporary positioning reference stake is set at the center of the crown to ensure the positioning accuracy of subsequent bricklaying. High-temperature refractory mortar is used to fill the spaces between adjacent mullite bricks, with the mortar thickness strictly controlled at 2 mm. The high-temperature refractory mortar must meet the following performance requirements: refractoriness > 1750℃, compressive strength at 25℃ > 30 MPa, and compressive strength at 300℃ > 25 MPa. The mortar must be thoroughly mixed during construction to ensure a dense and void-free filling.

[0031] S3. Composite Construction and Interlocking Positioning of Staggered Brick Layers: After the bottom layer of mullite bricks is completed and passes inspection, the composite construction of staggered brick layers begins. The overlapping surfaces of the staggered bricks are pre-set with a matching interlocking structure to the mullite brick layer, with the interlocking depth controlled at 8mm to ensure a tight fit between the two layers and improve overall structural stability. During construction, the centerline of the staggered bricks is offset from the centerline of the joints in the bottom layer of mullite bricks by one-third of the brick width, effectively preventing the joints from being continuous between layers. After each layer of staggered bricks is laid, the radial displacement and circumferential curvature are immediately calibrated using a laser positioning instrument to ensure the construction accuracy of the staggered brick layer meets design requirements.

[0032] S4. Layered Preloading and Defect Detection: The entire arch is preloaded in layers, with the preloading pressure gradually increasing from the arch foot to the arch crown. The specific increase is as follows: Starting from the arch foot, a baseline preload of 0.3 MPa is applied first. Then, pressure is applied in segments along the arch's curvature towards the arch crown, with each segment's pressure gradient controlled at 0.1 MPa, gradually transitioning to the arch crown area. Finally, the preloading pressure at the arch crown stabilizes at 0.8 MPa. The preloading time for each area of ​​the entire arch is controlled at 30 minutes. During the preloading process, the arch deformation is monitored in real time. After preloading is completed, an ultrasonic flaw detector is used to check the brick layer adhesion, focusing on the tightness of the adhesion between bricks and between brick layers. If defects such as substandard adhesion or gaps are found, the bricks must be removed and rebuilt until the inspection is passed.

[0033] S5. Overall Fixing and Identification During Transportation: After passing defect inspection, the arch is fixed as a whole using detachable clamps. Flexible protective pads are placed at the contact points between the clamps and the bricks to prevent damage to the brick surface. After fixing, the arch is clearly and accurately labeled with zone numbers to facilitate subsequent on-site installation and connection. Finally, the pre-assembled arch is horizontally transported to the storage area, avoiding collisions and vibrations during transportation. The storage area must be flat and dry, and protective measures must be taken to prevent the arch from getting damp or damaged.

[0034] Comparative Example 2 A method for pre-assembling the arch at the outlet of a dry quenching chamber, employing a composite masonry technique of mullite brick layers and staggered brick layers, specifically includes: S1. Pre-assembly Preparation and Benchmark Calibration: Construct an arc-shaped pre-assembly platform that matches the actual working conditions of the arch at the outlet of the quenching chamber. The platform surface is covered with a high-temperature resistant, anti-slip pad, and the bottom of the platform is equipped with a fine-tuning lifting mechanism to ensure that the platform's curvature and height can be adjusted as needed to meet the pre-assembly benchmark requirements. The high-temperature resistant, anti-slip pad must meet the following performance parameters: Shore hardness of 65HA, compressive strength at 25℃ > 15MPa, compressive strength retention rate at 300℃ ≥ 80%, and friction coefficient of the pad ≥ 0.8 to ensure the stability of the bricks during pre-assembly and prevent slippage or damage. S2. Construction of the Base Mullite Brick Layer: The mullite bricks are preheated at 80℃ for 1.5 hours, then heated to 150℃ at a rate of 1℃ / min and held for 2 hours. They are then cooled to 120℃ at a rate of 1℃ / min and held for 0.5 hours. After preheating, they are allowed to cool naturally to room temperature. Using the base surface as a reference, the base mullite brick layer is laid symmetrically from the arch foot to the arch crown. During construction, the flatness of the brick layer is checked with a straightedge every three bricks to ensure a flatness deviation of no more than 0.4mm / m. After reaching the arch crown, a temporary positioning reference stake is set at the center of the crown to ensure the positioning accuracy of subsequent bricklaying. High-temperature refractory mortar is used to fill the spaces between adjacent mullite bricks, with the mortar thickness strictly controlled to 2mm. The high-temperature refractory mortar must meet the following performance requirements: refractoriness > 1750℃, compressive strength at 25℃ > 30MPa, and compressive strength at 300℃ > 25MPa. During construction, the mortar must be stirred evenly to ensure that it is filled densely without gaps.

[0035] S3. Composite Construction and Interlocking Positioning of Staggered Brick Layers: After the bottom layer of mullite bricks is completed and passes inspection, the composite construction of staggered brick layers begins. The overlapping surfaces of the staggered bricks are pre-set with a matching interlocking structure to the mullite brick layer, with the interlocking depth controlled at 8mm to ensure a tight fit between the two layers and improve overall structural stability. During construction, the centerline of the staggered bricks is offset from the centerline of the joints in the bottom layer of mullite bricks by one-third of the brick width, effectively preventing the joints from being continuous between layers. After each layer of staggered bricks is laid, the radial displacement and circumferential curvature are immediately calibrated using a laser positioning instrument to ensure the construction accuracy of the staggered brick layer meets design requirements.

[0036] S4. Layered Preloading and Defect Detection: The entire arch is preloaded in layers, with the preloading pressure gradually increasing from the arch foot to the arch crown. The specific increase is as follows: Starting from the arch foot, a baseline preload of 0.3 MPa is applied first. Then, pressure is applied in segments along the arch's curvature towards the arch crown, with each segment's pressure gradient controlled at 0.1 MPa, gradually transitioning to the arch crown area. Finally, the preloading pressure at the arch crown stabilizes at 0.8 MPa. The preloading time for each area of ​​the entire arch is controlled at 30 minutes. During the preloading process, the arch deformation is monitored in real time. After preloading is completed, an ultrasonic flaw detector is used to check the brick layer adhesion, focusing on the tightness of the adhesion between bricks and between brick layers. If defects such as substandard adhesion or gaps are found, the bricks must be removed and rebuilt until the inspection is passed.

[0037] S5. Overall Fixing and Identification During Transportation: After passing defect inspection, the arch is fixed as a whole using detachable clamps. Flexible protective pads are placed at the contact points between the clamps and the bricks to prevent damage to the brick surface. After fixing, the arch is clearly and accurately labeled with zone numbers to facilitate subsequent on-site installation and connection. Finally, the pre-assembled arch is horizontally transported to the storage area, avoiding collisions and vibrations during transportation. The storage area must be flat and dry, and protective measures must be taken to prevent the arch from getting damp or damaged.

[0038] Comparative Example 3 A method for pre-assembling the arch at the outlet of a dry quenching chamber, employing a composite masonry technique of mullite brick layers and staggered brick layers, specifically includes: S1. Pre-assembly Preparation and Benchmark Calibration: Construct an arc-shaped pre-assembly platform that matches the actual working conditions of the arch at the outlet of the quenching chamber. The platform surface is covered with a high-temperature resistant, anti-slip pad, and the bottom of the platform is equipped with a fine-tuning lifting mechanism to ensure that the platform's curvature and height can be adjusted as needed to meet the pre-assembly benchmark requirements. The high-temperature resistant, anti-slip pad must meet the following performance parameters: Shore hardness of 65HA, compressive strength at 25℃ > 15MPa, compressive strength retention rate at 300℃ ≥ 80%, and friction coefficient of the pad ≥ 0.8 to ensure the stability of the bricks during pre-assembly and prevent slippage or damage. S2. Construction of the Base Mullite Brick Layer: The mullite bricks need to be preheated. The preheating process parameters are as follows: hold at 80℃ for 1.5 hours, then heat to 150℃ at a rate of 1℃ / min and hold for 2 hours, then cool to 120℃ at a rate of 1℃ / min and hold for 0.5 hours. After preheating, allow to cool naturally to room temperature for later use. Using the masonry reference surface as a guide, lay the base mullite brick layer symmetrically from the arch foot to the arch crown. During the masonry process, check the flatness of the brick layer with a straightedge every 3 bricks to ensure that the flatness deviation does not exceed 0.4mm / m. After reaching the arch crown, set a temporary positioning reference pile at the center of the arch crown to ensure the positioning accuracy of subsequent masonry. High-temperature refractory mortar is used to fill the gaps between adjacent mullite bricks, and the mortar thickness is strictly controlled to 2mm. The high-temperature refractory mortar must meet the following performance requirements: refractoriness > 1750℃, compressive strength at 25℃ > 30MPa, and compressive strength at 300℃ > 25MPa. During construction, the mortar must be stirred evenly to ensure that it is filled densely without gaps.

[0039] S3. Composite Construction and Interlocking Positioning of Staggered Brick Layers: After the bottom layer of mullite bricks is completed and passes inspection, the composite construction of staggered brick layers begins. The overlapping surfaces of the staggered bricks are pre-set with a matching interlocking structure to the mullite brick layer, with the interlocking depth controlled at 8mm to ensure a tight fit between the two layers and improve overall structural stability. During construction, the centerline of the staggered bricks is offset from the centerline of the joints in the bottom layer of mullite bricks by one-third of the brick width, effectively preventing the joints from being continuous between layers. After each layer of staggered bricks is laid, the radial displacement and circumferential curvature are immediately calibrated using a laser positioning instrument to ensure the construction accuracy of the staggered brick layer meets design requirements.

[0040] S4. Layered preloading and defect detection: Apply a uniform preload of 0.6 MPa to the entire arch and control the preloading time to 30 minutes. Monitor the deformation of the arch in real time during the preloading process. After the preloading is completed, use an ultrasonic flaw detector to check the brick layer adhesion. Focus on checking the tightness of the adhesion between bricks and between brick layers. If defects such as substandard adhesion or gaps are found, the bricks must be demolished and rebuilt in time until the test is qualified.

[0041] S5. Overall Fixing and Identification During Transportation: After passing defect inspection, the arch is fixed as a whole using detachable clamps. Flexible protective pads are placed at the contact points between the clamps and the bricks to prevent damage to the brick surface. After fixing, the arch is clearly and accurately labeled with zone numbers to facilitate subsequent on-site installation and connection. Finally, the pre-assembled arch is horizontally transported to the storage area, avoiding collisions and vibrations during transportation. The storage area must be flat and dry, and protective measures must be taken to prevent the arch from getting damp or damaged.

[0042] Comparative Example 4 A method for pre-assembling the arch at the outlet of a dry quenching chamber, employing a composite masonry technique of mullite brick layers and staggered brick layers, specifically includes: S1. Pre-assembly Preparation and Benchmark Calibration: Construct an arc-shaped pre-assembly platform that matches the actual working conditions of the arch at the outlet of the quenching chamber. The platform surface is covered with a high-temperature resistant, anti-slip pad, and the bottom of the platform is equipped with a fine-tuning lifting mechanism to ensure that the platform's curvature and height can be adjusted as needed to meet the pre-assembly benchmark requirements. The high-temperature resistant, anti-slip pad must meet the following performance parameters: Shore hardness of 65HA, compressive strength at 25℃ > 15MPa, compressive strength retention rate at 300℃ ≥ 80%, and friction coefficient of the pad ≥ 0.8 to ensure the stability of the bricks during pre-assembly and prevent slippage or damage. S2. Construction of the Base Mullite Brick Layer: The mullite bricks need to be preheated. The preheating process parameters are as follows: hold at 80℃ for 1.5 hours, then heat to 150℃ at a rate of 1℃ / min and hold for 2 hours, then cool to 120℃ at a rate of 1℃ / min and hold for 0.5 hours. After preheating, allow to cool naturally to room temperature for later use. Using the masonry reference surface as a guide, lay the base mullite brick layer symmetrically from the arch foot to the arch crown. During the masonry process, check the flatness of the brick layer with a straightedge every 3 bricks to ensure that the flatness deviation does not exceed 0.4mm / m. After reaching the arch crown, set a temporary positioning reference pile at the center of the arch crown to ensure the positioning accuracy of subsequent masonry. High-temperature refractory mortar is used to fill the gaps between adjacent mullite bricks, and the mortar thickness is strictly controlled to 2mm. The high-temperature refractory mortar must meet the following performance requirements: refractoriness > 1750℃, compressive strength at 25℃ > 30MPa, and compressive strength at 300℃ > 25MPa. During construction, the mortar must be stirred evenly to ensure that it is filled densely without gaps.

[0043] S3. Composite Construction and Interlocking Positioning of Staggered Brick Layers: After the bottom layer of mullite bricks is completed and passes inspection, the composite construction of staggered brick layers begins. The overlapping surfaces of the staggered bricks are pre-set with a matching interlocking structure to the mullite brick layer, with the interlocking depth controlled at 8mm to ensure a tight fit between the two layers and improve overall structural stability. During construction, the centerline of the staggered bricks is offset from the centerline of the joints in the bottom layer of mullite bricks by one-third of the brick width, effectively preventing the joints from being continuous between layers. After each layer of staggered bricks is laid, the radial displacement and circumferential curvature are immediately calibrated using a laser positioning instrument to ensure the construction accuracy of the staggered brick layer meets design requirements.

[0044] S4. Layered Preloading and Defect Detection: The entire arch is subjected to layered preloading. The preloading pressure gradually increases from the arch crown to the arch foot. The specific increase method is as follows: Starting from the arch crown, a reference preload of 0.3 MPa is applied first. Then, pressure is applied in segments along the arch curvature towards the arch foot, with the pressure gradient of each segment also controlled at 0.1 MPa. Finally, the preloading pressure at the arch foot is stabilized at 0.8 MPa. The preloading time for each area of ​​the entire arch is still 30 minutes. During the preloading process, the deformation of the arch is monitored in real time. After the preloading is completed, an ultrasonic flaw detector is used to check the brick layer adhesion, focusing on the tightness of the adhesion between bricks and between brick layers. If defects such as substandard adhesion or gaps are found, the bricks must be demolished and rebuilt in a timely manner until the inspection is qualified.

[0045] S5. Overall Fixing and Identification During Transportation: After passing defect inspection, the arch is fixed as a whole using detachable clamps. Flexible protective pads are placed at the contact points between the clamps and the bricks to prevent damage to the brick surface. After fixing, the arch is clearly and accurately labeled with zone numbers to facilitate subsequent on-site installation and connection. Finally, the pre-assembled arch is horizontally transported to the storage area, avoiding collisions and vibrations during transportation. The storage area must be flat and dry, and protective measures must be taken to prevent the arch from getting damp or damaged.

[0046] Comparative Example 5 A method for pre-assembling the arch at the outlet of a dry quenching chamber, employing a composite masonry technique of mullite brick layers and staggered brick layers, specifically includes: S1. Pre-assembly Preparation and Benchmark Calibration: Construct an arc-shaped pre-assembly platform that matches the actual working conditions of the arch at the outlet of the quenching chamber. The platform surface is covered with a high-temperature resistant, anti-slip pad, and the bottom of the platform is equipped with a fine-tuning lifting mechanism to ensure that the platform's curvature and height can be adjusted as needed to meet the pre-assembly benchmark requirements. The high-temperature resistant, anti-slip pad must meet the following performance parameters: Shore hardness of 65HA, compressive strength at 25℃ > 15MPa, compressive strength retention rate at 300℃ ≥ 80%, and friction coefficient of the pad ≥ 0.8 to ensure the stability of the bricks during pre-assembly and prevent slippage or damage. S2. Construction of the Base Mullite Brick Layer: The mullite bricks need to be preheated. The preheating process parameters are as follows: hold at 80℃ for 1.5 hours, then heat to 150℃ at a rate of 1℃ / min and hold for 2 hours, then cool to 120℃ at a rate of 1℃ / min and hold for 0.5 hours. After preheating, allow to cool naturally to room temperature for later use. Using the masonry reference surface as a guide, lay the base mullite brick layer symmetrically from the arch foot to the arch crown. During the masonry process, check the flatness of the brick layer with a straightedge every 3 bricks to ensure that the flatness deviation does not exceed 0.4mm / m. After reaching the arch crown, set a temporary positioning reference pile at the center of the arch crown to ensure the positioning accuracy of subsequent masonry. High-temperature refractory mortar is used to fill the gaps between adjacent mullite bricks, and the mortar thickness is strictly controlled to 2mm. The high-temperature refractory mortar must meet the following performance requirements: refractoriness > 1750℃, compressive strength at 25℃ > 30MPa, and compressive strength at 300℃ > 25MPa. During construction, the mortar must be stirred evenly to ensure that it is filled densely without gaps.

[0047] S3. Composite Construction and Interlocking Positioning of Staggered Brick Layers: After the bottom layer of mullite bricks is completed and passes inspection, the composite construction of staggered brick layers begins. The overlapping surfaces of the staggered bricks are pre-set with a matching interlocking structure to the mullite brick layer, with the interlocking depth controlled at 8mm to ensure a tight fit between the two layers and improve overall structural stability. During construction, the centerline of the staggered bricks is offset from the centerline of the joints in the bottom layer of mullite bricks by one-third of the brick width, effectively preventing the joints from being continuous between layers. After each layer of staggered bricks is laid, the radial displacement and circumferential curvature are immediately calibrated using a laser positioning instrument to ensure the construction accuracy of the staggered brick layer meets design requirements.

[0048] S4. Pre-compression and defect detection: The entire arch is subjected to a one-time sudden pressure increase, directly raising the pressure from 0MPa to the target pressure of 0.8MPa at the top of the arch. This pressure is then maintained for 30 minutes. During the pre-compression process, the deformation of the arch is monitored in real time. After the pre-compression is completed, an ultrasonic flaw detector is used to check the brick layer adhesion, focusing on the tightness of the adhesion between bricks and between brick layers. If defects such as substandard adhesion or gaps are found, the bricks must be demolished and rebuilt in a timely manner until the inspection is qualified.

[0049] S5. Overall Fixing and Identification During Transportation: After passing defect inspection, the arch is fixed as a whole using detachable clamps. Flexible protective pads are placed at the contact points between the clamps and the bricks to prevent damage to the brick surface. After fixing, the arch is clearly and accurately labeled with zone numbers to facilitate subsequent on-site installation and connection. Finally, the pre-assembled arch is horizontally transported to the storage area, avoiding collisions and vibrations during transportation. The storage area must be flat and dry, and protective measures must be taken to prevent the arch from getting damp or damaged.

[0050] Performance testing The performance of the pre-assembled arches prepared by the pre-assembly method for the dry quenching chamber outlet arch provided in Examples 1-3 and Comparative Examples 1-5 of this application was tested. The specific test items are as follows: Compressive strength: The compressive strength of the specimens was tested at 25℃ and 300℃, in accordance with the national standard GB / T 5072-2023 "Test Method for Compressive Strength of Refractory Materials at Room Temperature". High-temperature stability: Tested according to national standard GB / T 30873-2014 "Test Method for Thermal Shock Resistance of Refractory Materials"; Deformation resistance: Tested according to national standard GB / T 5073-2022 "Refractories - Test Method for Compression Creep"; The specific statistical results are shown in Table 1.

[0051] Table 1 Performance parameters of the pre-assembled arches in Examples 1-3 and Comparative Examples 1-5 As shown in Table 1, the pre-assembled arch prepared by the pre-assembly method for the outlet arch of the dry quenching chamber provided in this application exhibits significant comprehensive performance. It possesses high compressive strength at both room temperature and high temperature, strong thermal shock resistance, and low high-temperature creep rate. The use of mullite brick preheating treatment, staggered brick interlocking structure, and reasonable staggered joint settings, combined with a layered increasing pre-compression method from the arch foot to the arch top, enhances the brick bonding density and structural stability. The pre-assembled arch prepared by this method exhibits high temperature resistance, deformation resistance, and strong thermal shock resistance, making it suitable for the harsh working conditions of the dry quenching chamber and extending the service life of the arch.

[0052] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A method for pre-assembling the arch at the outlet of a dry quenching chamber, characterized in that, The composite masonry process using mullite brick layers and staggered brick layers includes the following steps: S1, pre-assembly preparation and benchmark calibration; S2, benchmark masonry of the bottom mullite brick layer; S3, composite masonry and interlocking positioning of the staggered brick layer; S4, layered pre-loading and defect detection; S5, overall fixing and marking for transportation.

2. The method for pre-assembling the arch at the outlet of the dry quenching chamber according to claim 1, characterized in that, In step S1, an arc-shaped pre-assembly platform matching the actual working conditions of the arch at the outlet of the quenching chamber is constructed. The surface of the platform is covered with a high-temperature resistant and anti-slip pad, and a fine-adjustable lifting mechanism is installed at the bottom of the platform.

3. The method for pre-assembling the arch at the outlet of the dry quenching chamber according to claim 1, characterized in that, In step S2, the mullite bricks need to be kept at 80-100℃ for 1.5-2 hours, heated to 150-200℃ at a heating rate of 1-3℃ / min, kept at 1-3℃ / min for 2-3 hours, and cooled to 120-140℃ at a cooling rate of 1-2℃ / min for 0.5-1 hours.

4. The method for pre-assembling the arch at the outlet of the dry quenching chamber according to claim 2, characterized in that, The high-temperature resistant anti-slip pad has a Shore hardness of 65-75HA, a compressive strength of >15MPa at 25℃, a compressive strength retention rate of ≥80% at 300℃, and a friction coefficient of ≥0.

8.

5. The method for pre-assembling the arch at the outlet of the dry quenching chamber according to claim 1, characterized in that, In step S2, the bottom layer of mullite bricks is laid using the masonry reference surface as a reference, and the masonry is carried out symmetrically from the arch foot to the arch top. Every 3-5 bricks are laid, the flatness of the brick layer is checked with a straightedge. The flatness deviation does not exceed 0.4mm / m. After the masonry reaches the arch top, a temporary positioning reference pile is set at the center of the arch top. High-temperature refractory mortar is used to fill the gaps between adjacent mullite bricks, and the mortar thickness is controlled at 2-3mm.

6. The method for pre-assembling the arch at the outlet of the dry quenching chamber according to claim 5, characterized in that, The high-temperature refractory slurry has a refractoriness of >1750℃, a compressive strength of >30MPa at 25℃, and a high-temperature compressive strength of >25MPa. The slurry must be stirred evenly during construction.

7. The method for pre-assembling the arch at the outlet of the dry quenching chamber according to claim 1, characterized in that, In step S3, the overlapping surfaces of the staggered bricks are provided with a concave-convex interlocking structure that matches the mullite brick layer, with a concave-convex interlocking depth of 8-12mm.

8. The method for pre-assembling the arch at the outlet of the dry quenching chamber according to claim 7, characterized in that, The center line of the staggered brick is staggered from the center line of the brick joint of the bottom mullite brick layer, and the stagger distance is 1 / 3 to 1 / 2 of the width of the brick. The radial displacement and circumferential curvature are calibrated by a laser positioning instrument after each layer of staggered brick is laid.

9. The method for pre-assembling the arch at the outlet of the dry quenching chamber according to claim 1, characterized in that, In step S4, the preloading pressure gradually increases from the arch foot to the arch crown. The specific increase method is as follows: starting from the arch foot, a reference preload of 0.3-0.5 MPa is applied first, and then pressure is applied in segments along the arch curvature towards the arch crown. The pressure gradient of each segment is controlled at 0.1-0.2 MPa, gradually transitioning to the arch crown area. Finally, the preloading pressure at the arch crown stabilizes at 0.8-1.0 MPa. The preloading time for each area of ​​the entire arch is controlled at 30-40 minutes. After the preloading is completed, an ultrasonic flaw detector is used to check the brick layer adhesion.

10. The method for pre-assembling the arch at the outlet of the dry quenching chamber according to claim 1, characterized in that, In step S5, a detachable clamp is used to fix the arch as a whole. A flexible protective pad is set at the contact part between the clamp and the brick. After the arch is divided into sections and numbered, it is horizontally transported to the storage area to avoid collision and vibration.

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