Metallurgical guide tube lining construction tool and method

Abstract

The application discloses a metallurgical flow guide pipe lining masonry tool and method, and relates to the field of steel metallurgical continuous casting equipment. The tool comprises a circular base plate, a main load-bearing rod, four auxiliary load-bearing rods, multiple connecting steel plates, a ring-shaped lifting buckle and a positioning ring. The construction method cooperating with the tool comprises the following steps: laying bottom layer block bricks along the outer side of the positioning ring on the ground and stacking the block bricks layer by layer to form a pre-masonry brick body; lifting the pre-masonry brick body into the flow guide pipe as a whole through the lifting buckle, wherein the pre-masonry brick body is blocked by the circular base plate, and the base plate is separated from the brick body by penetrating the center hole of the base plate; then lifting the flow guide pipe out, and leaving the tool on the ground. The application realizes the ground pre-masonry and rapid whole-pipe entering of the lining, greatly improves the masonry efficiency and quality, and supports multiple-tool circulating flow operation.

Description

Technical Field

[0001] This invention relates to the field of continuous casting equipment in iron and steel metallurgy, and more specifically, to a tooling and method for lining a metallurgical guide pipe. Background Technology

[0002] In the vacuum casting process of the metallurgical industry, the guide pipe is used to transport molten steel from the ladle to the casting chamber or tundish in a vacuum environment. The refractory brick lining of the guide pipe is in direct contact with the high-temperature molten steel and is subject to long-term erosion and chemical corrosion by the molten steel. It is a periodic consumable part and needs to be replaced regularly.

[0003] Currently, the industry generally adopts the assembly process of "laying bricks first, then sleeve" for the inner lining of the diversion pipe: first, refractory bricks are laid layer by layer on the base of the diversion pipe. After the brick height and verticality are tested and found to meet the standards, the outer wall of the diversion pipe (steel cylinder) is then inserted from above, and the bottom outer edge of the cylinder is welded and fixed to the base.

[0004] The inherent drawback of this process is that when the refractory bricks reach the end of their service life and need to be replaced, because the bricks are enclosed within the cavity formed by the cylinder and the base, it is necessary to use methods such as gas cutting to cut open the weld between the base and the cylinder in order to remove the old bricks and rebuild the structure. Repeated welding and cutting operations lead to a series of problems: (1) Accumulation of component damage. Each cutting and re-welding will generate heat effects in the weld area of ​​the base and the cylinder, causing the material metallographic structure to deteriorate and residual stress to accumulate. After long-term use, weld cracking or cylinder deformation is likely to occur.

[0005] (2) Deformation of the cylinder increases the difficulty of masonry. After the cylinder is deformed, the roundness and verticality of the inner diameter decrease, and it is difficult to guarantee the fit between the cylinder and the newly laid refractory bricks, which affects the masonry quality and the service life of the bricks.

[0006] (3) The maintenance cycle is long and the labor intensity is high. A series of processes such as cutting old welds, cleaning welding slag, re-laying bricks, and re-welding all require a lot of time. Moreover, the smoke and arc light generated by cutting and welding operations are detrimental to the health of workers and seriously affect the normal production rhythm on site.

[0007] (4) Production rhythm is disrupted. Vacuum casting is a key process in steel smelting. If the maintenance time of the guide pipe is too long, it will directly slow down the entire production rhythm and cause production capacity loss. Summary of the Invention

[0008] The purpose of this invention is to solve the problems mentioned in the background art, and to propose a tooling and method for lining a metallurgical guide pipe.

[0009] The technical solution adopted by this invention to solve its technical problem is: A quick-laying tooling for the inner lining of a metallurgical diversion pipe includes a circular base, a main load-bearing rod, four secondary load-bearing rods, multiple connecting steel plates, a ring-shaped lifting buckle, and a positioning ring. The main load-bearing rod is vertically installed at the center of the upper surface of the circular base, and the bottom end of the main load-bearing rod is fixed to the circular base; four secondary load-bearing rods are evenly distributed around the main load-bearing rod, and the bottom end of each secondary load-bearing rod is fixed to the upper surface of the circular base. Each secondary load-bearing rod is connected to the main load-bearing rod by a connecting steel plate, and the two sides of the connecting steel plate are fixed to the side wall of the secondary load-bearing rod and the side wall of the main load-bearing rod, respectively. The ring-shaped hook is fixed to the top of the main load-bearing rod; The positioning ring is fixed to the upper surface of the circular base. The positioning ring is arranged around the outside of the four auxiliary load-bearing rods, and the inner side wall of the positioning ring is tangent to the outer side wall of each auxiliary load-bearing rod. The diameter of the circular base is larger than the outer diameter of the positioning ring; The masonry tool is used in conjunction with the guide pipe, and the guide pipe has a circular base on the inner side of its bottom. The diameter of the circular base is smaller than the inner diameter of the circular ring base, and the outer diameter of the positioning ring is larger than the outer tangent circle diameter of each secondary load-bearing rod. The masonry tool is used to pre-lay the ground with the bottom layer of segmented refractory bricks and the integral ring-shaped refractory bricks. The bottom layer of segmented refractory bricks is assembled to form a ring-shaped bottom layer, and the integral ring-shaped refractory bricks are stacked layer by layer on the ring-shaped bottom layer.

[0010] Furthermore, the four auxiliary load-bearing rods are distributed at equal angles around the main load-bearing rod to ensure balanced force distribution and uniform brick positioning.

[0011] Furthermore, the circular base, positioning ring, bottom segmented refractory bricks, and guide pipe annular base satisfy a three-level dimensional chain constraint formula: in The outer diameter is the result of assembling the bottom layer of refractory bricks. The inner diameter of the circular base at the bottom of the guide tube. The diameter of the circular base is... The outer diameter of the positioning ring; this dimension chain simultaneously realizes the three functions of brick blocking, tooling protrusion, and hoisting support, and is the core design basis of the gravity separation mechanism; The outer edge of the circular base extends beyond the radial width of the outer edge of the positioning ring, which is greater than half the radial width of the overall annular refractory brick, in order to provide sufficient support area and prevent the pre-laid bricks from slipping during hoisting.

[0012] Furthermore, the axial height of the secondary load-bearing rod is greater than the axial height of the positioning ring, ensuring that the secondary load-bearing rod can provide lateral restraint for the multi-layer brickwork.

[0013] Furthermore, the lower part of the outer circumference of the positioning ring is provided with a guide cone surface that gradually decreases from top to bottom, and the cone angle of the guide cone surface is 15° to 45°.

[0014] Based on the above tooling, the present invention also provides a construction method, which is used in conjunction with a guide pipe, wherein a circular ring support is fixedly connected to the outer side of the upper part of the guide pipe in a circumferential direction, and a circular ring base is fixedly connected to the inner side of the bottom of the guide pipe in a circumferential direction. The construction method includes the following steps: S1. Place the masonry tool horizontally on the ground, and stack the bottom layer of refractory bricks along the outer side of the positioning ring to form a complete ring bottom layer; stack the whole ring refractory bricks layer by layer on top of the ring bottom layer to form a pre-built brick body. S2. Using a lifting device connected to a ring-shaped hoist, the masonry workpiece together with the pre-laid bricks is lifted as a whole and vertically placed into the inside of the guide pipe from the upper opening. S3. The pre-laid bricks fall to a point where their outer diameter is larger than the inner diameter of the circular base and they are blocked by the upper surface of the circular base. The circular base of the masonry tool, because its diameter is smaller than the inner diameter of the circular base, relies on its own weight to pass through the central hole of the circular base and separate from the pre-laid bricks. S4. Using lifting equipment, lift the circular support of the guide pipe, and lift the guide pipe together with the pre-laid bricks inside, leaving the masonry equipment on the ground.

[0015] Furthermore, the bottom layer of refractory bricks is a 1 / 5 ring structure, with five bottom layer refractory bricks assembled into a complete ring. The inner diameter of the assembled bottom layer refractory bricks is larger than the inner diameter of the overall ring refractory bricks, and the outer diameter of the assembled bottom layer refractory bricks is larger than the outer diameter of the overall ring refractory bricks, thus forming a stepped bottom layer that can both be secured to the circular base and support the upper layer of bricks.

[0016] Furthermore, when stacking the integral annular refractory bricks layer by layer, the inner wall of the integral annular refractory bricks and the outer wall of each secondary load-bearing rod are in a clearance fit with a preset radial gap; the preset radial gap Based on the pre-calculated high-temperature thermal expansion of refractory bricks, the following formula is satisfied:

[0017] in Let be the coefficient of linear thermal expansion of the refractory brick; for aluminosilicate refractory bricks, the value is [value missing]. , The inner diameter of the integral annular refractory brick. The value is the difference between the highest baking temperature and the room temperature; this design ensures that the tooling can be separated smoothly without jamming at room temperature, and that the thermal expansion of the brick body at high temperature can just eliminate the gaps and ensure the sealing performance of the inner lining.

[0018] Furthermore, in step S3, the masonry fixture must meet the critical condition of static self-weight separation: the total self-weight of the fixture must be greater than the maximum static friction force between the secondary load-bearing rod and the inner wall of the pre-laid brickwork, and the corresponding formula is: in The total weight of the masonry equipment. This is the sum of the maximum static friction forces. The static friction coefficient between the refractory brick and the steel sub-supporting rod is 0.15~0.3 under normal temperature and dry conditions. This is the sum of the radial normal forces acting on each of the secondary load-bearing rods; When the weight of the tooling does not meet the critical condition, forced separation by impact is performed: after the pre-laid brick body is stopped, the sling is loosened to allow the tooling to fall freely, using impulse to overcome adhesive resistance, and the minimum falling height satisfies the impulse formula:

[0019] in It is the acceleration due to gravity. The height of free fall. The impact time is 0.01~0.03s; this quantitative design can ensure the success rate of separation and avoid the risk of jamming.

[0020] After step S3 is completed, quartz sand is filled into the gap between the pre-laid brick body and the inner wall of the guide pipe. The quartz sand is compacted by vibration filling. The preferred particle size of the quartz sand is 0.5-2mm. Refractory mortar is then covered on the top layer of the pre-laid brick body to fix the brick lining and seal the gaps.

[0021] Furthermore, the detached guide tube is transferred to the baking oven for gradient high-temperature baking based on thermal expansion compensation, employing a three-stage precise heating system: 1. Room temperature heating stage: The temperature is raised from room temperature to 200℃, and the heating rate is controlled within 30℃ / h. The bricks expand slowly to gradually eliminate the gaps in the pre-built assembly and avoid the bricks being squeezed and broken due to rapid expansion. 2. Medium-temperature heating stage: The temperature is raised from 200℃ to 600℃, and the heating rate is controlled within 80℃ / h. The brick joint binder gradually pyrolyzes and carbonizes, and the quartz sand filling layer begins to expand and fill the radial gaps due to heat. 3. High-temperature insulation stage: The temperature is raised to above 800℃ and kept for 2-4 hours. The bricks are fully sintered and interlocked, and the quartz sand is fully expanded to seal the gaps. After the insulation is completed, the bricks are cooled with the furnace to complete the sintering and curing of the inner lining.

[0022] Furthermore, the construction method, used for continuous assembly line masonry operations on multiple diversion pipes, also includes the following steps: Step S5: After the masonry tooling in step S4 is left on the ground or a pre-set bottom receiving platform, the masonry tooling is lifted and moved out, and another set of masonry tooling that has pre-completed the pre-laid brickwork described in step S1 is lifted into the work position. Step S6: Use the second set of masonry tools to perform steps S2 to S4 on the next diversion pipe to form a parallel flow operation of "ground pre-masonry - hoisting and separation - tool removal - cyclic reuse"; wherein, multiple sets of the masonry tools are used alternately, so that the masonry cycle of the diversion pipe is decoupled from the pre-masonry preparation cycle, and continuous operation is achieved.

[0023] Compared with the prior art, the beneficial effects of the present invention are: I. Completely end the vicious cycle of "cutting-welding". The weld between the guide tube cylinder and the base is permanently preserved and does not require cutting. The maintenance time for a single tube is reduced from 6.5 hours in the traditional process to 1.2 hours. It eliminates the thermal damage and stress deformation caused by repeated hot cutting and welding to the cylinder, and significantly extends the service life of the equipment.

[0024] II. A Separation Mechanism That Delivers a Qualitative Efficiency Change Compared to Traditional Solutions. This invention breaks through the technical inertia of "tooling returning upwards along the same path," creatively adopting a "gravity-driven downward exit" separation method. After the pre-laid brickwork is stopped by the base, the tooling naturally exits through the central hole of the base under its own weight. The separation time is reduced from 5-8 minutes in the traditional core mold method to 3-5 seconds, and the downward separation causes zero disturbance to the already positioned brickwork, significantly improving the quality of the masonry. This mechanism requires no additional power, sensors, or control systems, achieving a fully automated effect of "separation upon placement."

[0025] III. Redefining the Functional Positioning of the Circular Base. In traditional processes, the welding structure between the circular base and the cylinder is the direct cause of the cutting and welding process; this invention transforms it into a dual-function component of "brick retention block" and "tool separation trigger," eliminating the need for temporary brackets and simultaneously completing the two opposite tasks of brick support and tool protrusion.

[0026] The positioning ring serves three functions simultaneously: pre-built benchmark, hoisting bracket, and separation guide. The tooling requires no moving parts or fasteners, resulting in a simplified structure and high reliability.

[0027] Fourth, a complete quantitative design system has been established, freeing us from reliance on experience.

[0028] This invention breaks through the traditional experience-based design mode of tooling, and constructs a three-level dimensional chain design criterion, critical mechanical conditions for self-weight separation, and a method for calculating impact separation impulse for the gravity separation mechanism. Furthermore, it links the pre-assembled gap and high-temperature baking regime through a thermal expansion formula to form a coordinated control. The entire solution has complete theoretical support and quantifiable engineering replicability. The above-mentioned quantitative design is a dedicated method for the "downward self-weight separation" technical route, and has no application scenarios or technical inspiration in traditional upward disassembly techniques, further enhancing the non-obviousness of the solution. Attached Figure Description

[0029] Figure 1 This is a schematic diagram showing the fit between the tooling and the guide tube of the present invention; Figure 2 This is a three-dimensional structural schematic diagram of the tooling of the present invention; Figure 3 This is a schematic diagram of the flow guide tube structure in this invention; Figure 4 This is the overall flow logic diagram of the present invention; Figure Labels 1. Circular base; 2. Main load-bearing rod; 3. Secondary load-bearing rod; 4. Connecting steel plate; 5. Ring-shaped hook; 6. Positioning ring; 7. Guide cone surface; 8. Flow guide pipe; 9. Circular ring base; 10. Circular ring support; 11. Bottom layer segmented refractory bricks; 12. Integral ring-shaped refractory bricks; 13. Flow guide pipe hook. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0031] The core concept of this invention lies in providing a masonry tooling and construction method that allows for the pre-laying of refractory bricks on the ground, the overall hoisting and placement of the diversion pipe 8, and automatic separation of the tooling. Through a precise dimensional chain design, a collaborative relationship is formed between the tooling, the refractory bricks, and the diversion pipe 8, enabling them to be "lifted, placed, and separated," fundamentally solving the industry problem of the traditional diversion pipe 8 requiring repeated cutting and welding to replace the refractory bricks.

[0032] One of the key design considerations: separation mechanism 1. Understanding of technical issues When faced with the problem of "how to put the refractory bricks into the guide pipe 8 and take out the tooling", the conventional technical approach is to hoist the bricks into the guide pipe 8 and then take the tooling out from the top of the guide pipe 8. The tooling is taken out in the same direction as it is put in or requires additional disassembly. Therefore, it is inevitable that complex clamping mechanisms, fasteners or additional operating steps are required.

[0033] 2. The design of this invention differs from conventional technical approaches. This invention completely changes the inertia of this technology and creatively adopts the separation direction of "penetrating downwards"—after the tooling puts the pre-laid brick body into the upper part of the guide pipe 8, instead of taking the tooling out upwards, the tooling is allowed to continue to move downwards under the action of gravity and naturally pass through the central hole of the circular base 9 at the bottom of the guide pipe 8.

[0034] This design differs from conventional technical approaches in that: First, the change in direction of movement. In conventional thinking, the tool is a means of "feeding bricks into the pipe," and after being fed in, it should naturally return along the same path (to be taken out upwards).

[0035] This invention extends the movement path of the tooling—changing it from "feeding in" to "passing through," allowing the tooling to exit directly from the bottom after completing the transfer of refractory bricks. This "passing through" rather than "returning" movement mode is not recorded in the field of lining construction of the guide pipe 8.

[0036] Second, a redefinition of "gravity." In conventional designs, gravity is an obstacle that needs to be overcome—the tooling must be prevented from falling after being hoisted in. This invention, however, transforms gravity into a force for separation—after the tooling completes the transfer of refractory bricks, separation can be achieved solely by its own weight, without any external intervention. This design concept of "turning resistance into power" reflects a creative application of physical laws.

[0037] Third, the separation process is fully automated. The separation process of this invention requires no human intervention or additional power source; the tooling and bricks are naturally separated during the reversing and transporting process of the guide pipe 8.

[0038] (I) Example 1: Foundation Construction Method The present invention proposes a rapid lining construction tool for a metallurgical guide pipe 8, which includes a circular base plate 1, a main load-bearing rod 2, four secondary load-bearing rods 3, multiple connecting steel plates 4, a ring-shaped lifting buckle 5, and a positioning ring 6.

[0039] The circular base 1 is a circular steel plate, and its diameter is determined according to the inner diameter of the circular annular base 9 at the bottom of the guide pipe 8.

[0040] The main load-bearing rod 2 is vertically welded to the geometric center of the upper surface of the circular base plate 1, and the bottom end of the main load-bearing rod 2 is fully welded to the circular base plate 1.

[0041] Four secondary load-bearing rods 3 are evenly distributed around the main load-bearing rod 2 at 90° angles, and the bottom end of each secondary load-bearing rod 3 is welded and fixed to the upper surface of the circular base plate 1.

[0042] To improve overall rigidity and stability, a connecting steel plate 4 is provided between each secondary load-bearing rod 3 and the main load-bearing rod 2. The two sides of the connecting steel plate 4 are welded to the side wall of the secondary load-bearing rod 3 and the side wall of the main load-bearing rod 2, respectively.

[0043] The ring-shaped hook 5 is welded to the top of the main load-bearing rod 2 and is used to connect the hook or sling of the lifting equipment.

[0044] The positioning ring 6 is a circular steel plate or section steel, which is horizontally welded to the upper surface of the circular base plate 1. The positioning ring 6 is arranged around the outside of the four auxiliary load-bearing rods 3. The inner sidewall of the positioning ring 6 is tangent to the outer sidewall of each auxiliary load-bearing rod 3, forming a circumferential positioning and support for the auxiliary load-bearing rods 3.

[0045] The critical dimensional relationships satisfy the three-level dimensional chain constraint formula: The meanings of each parameter and the design logic are as follows: The outer diameter of the bottom layer of refractory bricks 11 is larger than the inner diameter of the circular base 9, ensuring that the pre-laid bricks are reliably stopped by the circular base 9 when they fall, thus achieving brick retention. The diameter of the circular base 1 is smaller than the inner diameter of the circular base 9, ensuring that the tooling can pass through the center hole of the circular base 9 downwards to achieve automatic separation; The circular base provides radial support to the entire annular refractory brick 12, which is greater than half the radial width of the brick. This ensures stable support of the brick during ground pre-laying and hoisting, eliminating the risk of slippage.

[0046] The above dimensional relationships are necessary structural conditions for achieving the separation action of "tooling going downward and bricks being blocked," and none of them can be omitted.

[0047] (II) Construction Steps In this embodiment, a circular ring support is fixed to the outer circumference of the upper part of the guide pipe to be replaced, which is used for docking with the vacuum equipment; a circular ring base is welded to the inner circumference of the bottom of the guide pipe, which plays the role of supporting the inner lining brick during normal use of the guide pipe.

[0048] It should be noted that in the method of the present invention, the original weld between the outer wall (cylinder) of the guide tube and the annular base does not need to be cut, and the two remain as a permanently connected integral structure. This is one of the core differences between the method of the present invention and the traditional method - the present invention fundamentally eliminates the repeated "cutting-welding" process.

[0049] Step S1: Ground Pre-laying. Place the masonry tool horizontally on the ground, ensuring the circular base is on the ground. Stack the bottom layer of refractory bricks circumferentially along the outer wall of the positioning ring.

[0050] In this embodiment, the bottom layer of refractory bricks is a 1 / 5 ring structure, and five pieces are assembled to form a complete ring bottom layer. The inner arc surface of the bottom layer of refractory bricks fits the outer circumference of the positioning ring, which serves as the positioning reference to ensure the inner diameter accuracy and roundness of the bottom layer.

[0051] The inner diameter of the assembled bottom layer of refractory bricks is larger than the inner diameter of the overall annular refractory brick, and the outer diameter is larger than the outer diameter of the overall annular refractory brick. This dimensional relationship ensures that the bottom layer bricks can reliably sit on the annular base of the guide tube in subsequent steps, without being leaked by the inner hole of the annular base.

[0052] Above the annular base layer, monolithic annular refractory bricks are stacked layer by layer. The inner wall of the monolithic annular refractory bricks fits into the outer wall of each secondary load-bearing rod, forming a pre-built brick body. Multiple layers of refractory bricks are stacked one after another until the designed height is reached.

[0053] Step S2: Overall hoisting. Using a lifting device connected to the ring-shaped hook at the top of the main load-bearing rod, the masonry fixture and the pre-laid brickwork are lifted smoothly as a whole and placed vertically downwards into the inside of the diversion pipe from the upper opening.

[0054] Step S3: Gravity Separation. The pre-laid brick body continues to fall with the tooling. When the bottom surface of the bottom layer of refractory bricks contacts the upper surface of the bottom ring base of the guide pipe, the pre-laid brick body is blocked by the ring base and stops falling because the outer diameter of the bottom layer of refractory bricks is larger than the inner diameter of the ring base.

[0055] Meanwhile, the circular base of the masonry tool, because its diameter is smaller than the inner diameter of the annular base, continues to move downwards under its own gravity, passing through the central hole of the annular base and separating from the pre-laid bricks. At this point, the pre-laid bricks are retained on the annular base inside the guide pipe, while the tool detaches from the bricks.

[0056] This step is the core feature that distinguishes the method of this invention from all existing technologies: the separation direction of the tooling is downward, the separation driving force is the weight of the tooling itself, and the separation triggering mechanism is the inherent circular base of the guide tube. The entire process requires no additional power or manual intervention, achieving an automated effect of "separation upon arrival".

[0057] Step S4: Tooling Retention. Using lifting equipment, lift the outer ring support at the top of the guide pipe, and then lift the guide pipe along with the pre-laid brickwork inside. Since the tooling has been separated from the brickwork and the diameter of the circular base is smaller than the inner hole of the ring base, the tooling will naturally remain on the ground or a pre-set bottom support platform when lifting the guide pipe, and will not be lifted along with the guide pipe.

[0058] Step S5: Filling and Gradient Baking. Fill the annular gap between the outer wall of the pre-laid brickwork and the inner wall of the guide pipe with quartz sand. Use vibration filling to compact the quartz sand. The preferred quartz sand particle size is 0.5-2mm, which serves to provide heat insulation, buffering, and radial positioning. Seal the top layer of the pre-laid brickwork with refractory mortar.

[0059] The detached guide tube is then transferred into the baking oven for gradient high-temperature baking based on thermal expansion compensation, employing a three-stage precise heating system: During the ambient temperature heating stage (ambient temperature → 200℃): the heating rate is controlled within 30℃ / h, the bricks expand slowly to gradually eliminate the gaps in the pre-built assembly, avoid the bricks being squeezed and broken due to rapid thermal expansion, and at the same time slowly drain the residual moisture inside the bricks. Medium-temperature heating stage (200℃→600℃): The heating rate is controlled within 80℃ / h. The brick joint binder gradually pyrolyzes and carbonizes to form a carbon network. The quartz sand filling layer begins to expand under heat and gradually fills the radial gap between the brick body and the cylinder wall. High-temperature insulation stage (above 800℃): Insulation for 2-4 hours, the bricks are fully sintered and interlocked to form an integral structure, and the quartz sand completely expands thermally to seal all gaps; after the insulation is completed, the furnace is cooled to complete the sintering and solidification of the inner lining, and it can be put back into vacuum casting for use.

[0060] Typical calculation example: using aluminosilicate refractory bricks (α=6.5×10) -6 ℃ -1 Taking a brick with an inner diameter D of 500 mm and a baking temperature of 800℃ (ΔT = 780℃) as an example, the calculated δ = 6.5 × 10⁻⁶. -6 ×500×780≈2.54mm, meaning that the preset radial gap between the secondary load-bearing rod and the inner wall of the brick at room temperature is 2.5~3.0mm, which can simultaneously meet the requirements of smooth separation at room temperature and sealing compensation at high temperature.

[0061] Example 2: Assembly Line Cyclic Operation Method Based on Example 1, this embodiment expands the core advantage of the method of the present invention—that the tooling is separated from the brick and left on the ground, and that the guide tube and the base remain as an integral structure that does not require cutting—into an industrialized assembly line operation mode.

[0062] The construction method described herein is used for continuous, assembly-line lining replacement of multiple guide pipes. At least two sets of identical masonry fixtures are required, designated as fixture number one and fixture number two, respectively.

[0063] Step S5: Tooling Switching. After the first masonry tooling from Step S4 is left on the ground or a pre-set bottom receiving platform, the lifting equipment lifts the first tooling out of the work area and sends it to the pre-masonry station for the next pre-masonry preparation. At the same time, the second set of masonry tools, which has already completed the pre-masonry of the bricks described in Step S1 at another station, is lifted into the station.

[0064] Step S6: Cyclic Operation. Using the second set of masonry tools, perform steps S2 to S4 on the next guide pipe to be replaced with lining. Repeat this cycle to form a parallel flow operation mode of "ground pre-masonry - hoisting and separation - tooling removal - cyclic reuse".

[0065] In this mode, multiple sets of masonry tools are used alternately, decoupling the masonry cycle of the diversion pipe (from hoisting to filling completion) from the pre-masonry preparation cycle (stacking refractory bricks on the ground), eliminating waiting time between them and enabling continuous operation. This is equivalent to transforming the traditional "serial" construction process into a "parallel" assembly line, significantly improving overall maintenance efficiency.

[0066] Example 3: Separation Reliability Optimization This embodiment provides a quantitative optimization method to address the problem of poor separation in step S3, which may be caused by slight adhesion or misalignment of the refractory mortar in the brick joints.

[0067] In step S3, the static self-weight separation critical condition is first verified: the total self-weight of the tooling. It must be greater than the maximum static friction force between the secondary load-bearing rod and the inner wall of the pre-laid brickwork. That is, it satisfies the formula:

[0068] in The static friction coefficient between the refractory brick and the steel sub-supporting rod is 0.15~0.3 under normal temperature and dry conditions. This is the sum of the radial normal forces acting on the four secondary load-bearing rods.

[0069] When the weight of the tooling meets the critical condition, natural separation can be achieved by its own weight; when the weight does not meet the critical condition or there is slight adhesion of mortar in the brick joints, forced separation by impact is performed. After the pre-laid brickwork is stopped, the crane operator slacks the slings connecting the ring-shaped hoist, allowing the masonry fixture to move downwards in a near-free-fall manner. According to the impulse theorem, the minimum fall height required to ensure complete separation satisfies the formula:

[0070] in It is the acceleration due to gravity. The height of free fall. The impact time is 0.01~0.03s. This quantitative design can ensure the success rate of separation and avoid the risk of jamming. In engineering applications, the drop height is usually 50-200mm, which can be precisely adjusted by formula according to the weight of the tooling and the actual working conditions.

[0071] The impact inertia generated by the free fall motion is sufficient to overcome the static frictional resistance or slight adhesion between the inner wall of the pre-built brickwork and the outer wall of the secondary load-bearing rod, forcing the circular base to pass through the central hole of the circular base completely and cleanly, achieving reliable forced separation.

[0072] Once the tool has fallen to the bottom receiving platform or the ground, it can be re-hooked and removed.

[0073] Example 4: Tooling with guiding function This embodiment features an optimized design for the positioning ring structure, which is considered a preferred solution.

[0074] The lower part of the outer circumference of the positioning ring is provided with a guide cone surface that gradually decreases from top to bottom, and the cone angle of the cone surface is preferably in the range of 15° to 45°.

[0075] In step S2, when the masonry tooling and the pre-laid bricks are hoisted into the guide pipe, the hoisting speed is slowed down when the pre-laid bricks approach the circular base at the bottom of the guide pipe.

[0076] The guide cone surface first contacts the upper edge of the inner hole of the ring base. During the sliding engagement between the two, the coaxiality of the pre-laid brick axis and the ring base axis is automatically corrected to ensure that the bricks are evenly and accurately placed on the ring base.

[0077] In step S3, after the pre-laid bricks are placed on the circular base and before the final separation of the masonry fixture, the masonry fixture is lifted at least once (lifting height of about 5-15mm) by a lifting device and then released. This allows the gaps between the entire ring of refractory bricks to be adjusted by gravity, eliminating any possible local gaps or tilts between the brick layers, achieving a tight fit and horizontal stability between the brick layers, and then the fixture separation action is performed.

[0078] Comparison and effect data To verify the beneficial effects of the technical solution of the present invention, the method of the present invention is compared with two traditional methods, taking the replacement of the lining of a vacuum casting guide pipe (with an inner diameter of about 600 mm and a height of about 1200 mm) actually used in a steel plant as an example.

[0079] Comparative Example 1: Traditional "cut-weld" replacement method. That is, the conventional process described in the background art: cut the old weld between the outer wall of the guide tube and the base with an oxy-acetylene torch → remove the old bricks → manually lay new bricks layer by layer on the base → insert the tube → re-weld the tube and the base.

[0080] Comparative Example 2: Conventional core mold pre-laying method. After pre-laying bricks on the ground core mold, the entire core is hoisted into the cylinder. The core mold is pulled out from the top. Temporary supports or brackets need to be set under the bricks. Only after the core mold is completely pulled out can the bricks be placed on the bottom circular base.

[0081] The comparison data is shown in the table below:

[0082] Data Analysis: As can be seen from the table above, the technical solution of the present invention has achieved a qualitative breakthrough compared with traditional methods in terms of maintenance efficiency, equipment life protection, operational safety, and quality stability.

[0083] Specifically: 1. It fundamentally eliminates the vicious cycle of "cutting-welding". In Comparative Example 1, each liner replacement requires a cutting and a welding process, which is the root cause of cylinder deformation, weld cracking, and long maintenance cycles - a single maintenance takes up to 6.5 hours, of which welding preparation, welding, post-weld cooling, and weld inspection take up a lot of time.

[0084] Both the method of this invention and Comparative Example 2 avoid this step, but this invention achieves even greater efficiency. The single-tube maintenance time of Example 1 is only 48% of that of Comparative Example 2 and 18% of that of Comparative Example 1. In the assembly line mode of Example 2, the offline replacement time of the guide tube is shortened to about 0.5 hours (including only the hoisting, separation, and filling processes), and the daily output can reach 16 tubes, which is 5 times that of Comparative Example 2 and more than 13 times that of Comparative Example 1. The fundamental reason for this leap in efficiency is that the "gravity downward separation" mechanism compresses the tooling separation time from "minutes" to "seconds", and the tooling is immediately left outside after separation and can be directly put into the next cycle.

[0085] 2. Significant innovation in the separation mechanism. Comparative Example 2 uses an "upward extraction" method, which requires the full cooperation of lifting equipment during the separation process. Furthermore, the friction between the core mold and the inner wall of the brick during extraction can easily cause disturbance and misalignment of the brick layers, and the separation time is approximately 5-8 minutes.

[0086] This invention employs a "downward gravity-driven separation" method, where the separation occurs naturally the instant the brick is stopped by the circular base, requiring no additional operation. The separation time is only 3-5 seconds, and the process causes zero disturbance to the brick. This shift in separation direction, which differs from conventional techniques, is the core innovation of the entire technical solution.

[0087] 3. Ingenious functional transformation of the original structure. In Comparative Example 1, the circular base at the bottom of the guide pipe is the root cause of the closed process that "must be welded to the cylinder and must be cut to replace it". In Comparative Example 2, the base cannot provide axial support for the brick before the core mold is removed, and a temporary bracket needs to be added, which increases the complexity and uncertainty of construction.

[0088] This invention redefines this structure as a "brick retention block" and a "tool separation trigger," requiring no additional components. It perfectly solves the two key problems of brick axial positioning and automatic tool separation, demonstrating a creative expansion of the original structure's function and ending the destructive cycle of "cutting-welding" at its root.

[0089] 4. The dual function of the positioning ring reduces system complexity. During the ground pre-laying stage, the positioning ring serves as the outer mold reference for stacking the bottom layer of bricks, ensuring the accuracy of the inner diameter of the bottom layer; During the hoisting and separation phase, the same structure is transformed into a brick-supported step. This "dual-purpose" design reduces the number of specialized molds, making the tooling structure extremely streamlined while maintaining complete functionality.

[0090] In summary, the rapid lining tooling and construction method for metallurgical diversion pipes proposed in this invention provide a technical solution that significantly differs from traditional construction methods through the organic combination of three core innovative points: a gravity-driven downward separation mechanism that differs from conventional technical approaches, the functional transformation of the original structure, and the dual-functional design of the positioning ring that serves two purposes.

[0091] Its non-obviousness lies in the fact that, under the inherent thinking pattern, a person skilled in the art would not think of allowing the tooling to detach downwards, let alone using the circular base, which is regarded as a construction obstacle, as a key functional component of the separation mechanism. Once this mindset is broken, not only will the efficiency and safety improvements be beyond expectations, but the long-standing problem of "repeated cutting and welding" will also be fundamentally eliminated, and the resulting technical effects will be difficult for those skilled in the art to anticipate.

[0092] Meanwhile, this application also underwent a sealing test after high-temperature baking. The sealing performance of the guide pipe constructed using the method of this invention and baked at a high temperature of over 800°C was tested, and the results are shown in the table below.

[0093]

[0094] During the baking process, the quartz sand expands due to heat, further compressing the gaps. The brick binder pyrolyzes and carbonizes to form a continuous carbon network that fills the brick joints. High-temperature sintering causes the bricks to interlock tightly, forming an integral sealed structure. Test results show that the lining of the guide pipe constructed using the method of this invention has excellent sealing performance.

[0095] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A rapid lining construction tool for a metallurgical guide pipe, characterized in that, It includes a circular base (1), main load-bearing rod (2), four secondary load-bearing rods (3), multiple connecting steel plates (4), ring-shaped hook (5) and positioning ring (6); The main load-bearing rod (2) is vertically set at the center of the upper surface of the circular base plate (1), and the bottom end of the main load-bearing rod (2) is fixedly connected to the circular base plate (1); Four secondary load-bearing rods (3) are evenly distributed around the main load-bearing rod (2), and the bottom end of each secondary load-bearing rod (3) is fixed to the upper surface of the circular base plate (1). Each secondary load-bearing rod (3) is connected to the main load-bearing rod (2) by a connecting steel plate (4). The two sides of the connecting steel plate (4) are fixed to the side wall of the secondary load-bearing rod (3) and the side wall of the main load-bearing rod (2), respectively. The ring-shaped hook (5) is fixed to the top of the main load-bearing rod (2); The positioning ring (6) is fixed to the upper surface of the circular base (1). The positioning ring (6) is arranged around the outside of the four auxiliary load-bearing rods (3). The inner sidewall of the positioning ring (6) is tangent to the outer sidewall of each auxiliary load-bearing rod (3). The diameter of the circular base (1) is larger than the outer diameter of the positioning ring (6); The masonry tool is used in conjunction with the guide pipe (8), and the guide pipe (8) has a circular base (9) on the inner side of its bottom. The diameter of the circular base (1) is smaller than the inner diameter of the circular ring base (9), and the outer diameter of the positioning ring (6) is larger than the outer diameter of the outer circle of each auxiliary load-bearing rod (3); The masonry tool is used to pre-lay the ground with the bottom layer of segmented refractory bricks (11) and the integral ring refractory bricks (12). The bottom layer of segmented refractory bricks (11) is assembled to form an annular bottom layer, and the integral ring refractory bricks (12) are stacked layer by layer on the annular bottom layer.

2. The rapid lining installation tool for a metallurgical guide pipe according to claim 1, characterized in that, The four auxiliary load-bearing rods (3) are distributed at equal angles around the main load-bearing rod (2) in the circumference.

3. The rapid lining tooling for a metallurgical guide pipe according to claim 1, characterized in that, The circular base (1), positioning ring (6), bottom segmented refractory bricks (11), and guide pipe (8) and circular base (9) satisfy the three-level dimensional chain constraint formula: in The outer diameter of the bottom layer of refractory bricks (11) after assembly. The inner diameter of the bottom annular base of the guide tube (8) is... The diameter of the circular base (1) is The outer diameter of the positioning ring (6); The outer edge of the circular base (1) extends beyond the radial width of the outer edge of the positioning ring (6), which is greater than half the radial width of the overall annular refractory brick (12); The lower part of the outer circumference of the positioning ring (6) is provided with a guide cone surface (7) that gradually decreases from top to bottom, and the cone angle of the guide cone surface (7) is 15° to 45°.

4. The rapid lining installation tool for a metallurgical guide pipe according to claim 1, characterized in that, The axial height of the secondary load-bearing rod (3) is greater than the axial height of the positioning ring (6).

5. A construction method using the rapid lining tooling for the metallurgical guide pipe as described in claim 1, characterized in that, When used in conjunction with a guide tube, a circular ring support is circumferentially fixed to the upper outer side of the guide tube, and a circular ring base is circumferentially fixed to the bottom inner side of the guide tube; the construction method includes the following steps: S1. Place the masonry tool horizontally on the ground, and stack the bottom layer of refractory bricks along the outer side of the positioning ring to form a complete ring bottom layer; stack the whole ring refractory bricks layer by layer on top of the ring bottom layer to form a pre-built brick body. S2. Using a lifting device connected to a ring-shaped hoist, the masonry workpiece together with the pre-laid bricks is lifted as a whole and vertically placed into the inside of the guide pipe from the upper opening. S3. The pre-laid bricks fall to a point where their outer diameter is larger than the inner diameter of the circular base and they are blocked by the upper surface of the circular base. The circular base of the masonry tool, because its diameter is smaller than the inner diameter of the circular base, relies on its own weight to pass through the central hole of the circular base and separate from the pre-laid bricks. S4. Using lifting equipment, lift the circular support of the guide pipe, and lift the guide pipe together with the pre-laid bricks inside, leaving the masonry equipment on the ground.

6. The construction method of the rapid lining tooling for a metallurgical guide pipe according to claim 5, characterized in that, The bottom layer of refractory bricks has a 1 / 5 ring structure, and the five bottom layer refractory bricks are assembled into a complete ring. The inner diameter of the assembled bottom layer refractory bricks is larger than the inner diameter of the overall ring refractory bricks, and the outer diameter of the assembled bottom layer refractory bricks is larger than the outer diameter of the overall ring refractory bricks.

7. The construction method of the rapid lining tooling for a metallurgical guide pipe according to claim 5, characterized in that, When stacking the monolithic annular refractory bricks layer by layer, the inner wall of the monolithic annular refractory bricks and the outer wall of each secondary load-bearing rod are fitted with a preset radial clearance; the preset radial clearance Based on the pre-calculated high-temperature thermal expansion of refractory bricks, the following formula is satisfied: in The coefficient of linear thermal expansion of refractory bricks is given. The inner diameter of the integral annular refractory brick. This is the difference between the highest baking temperature and the room temperature.

8. The construction method of the rapid lining tooling for a metallurgical diversion pipe according to claim 5, characterized in that, In step S3, the masonry fixture must meet the critical condition of static self-weight separation: the total self-weight of the fixture must be greater than the maximum static friction force between the secondary load-bearing rod and the inner wall of the pre-laid brickwork. The corresponding formula is: in The total weight of the masonry equipment. This is the sum of the maximum static friction forces. The static friction coefficient between the refractory brick and the steel sub-support rod is given. This is the sum of the radial normal forces acting on each of the secondary load-bearing rods; When the weight of the tooling does not meet the critical condition, forced separation by impact is performed: after the pre-laid brick body is stopped, the sling is loosened to allow the tooling to fall freely, using impulse to overcome adhesive resistance, and the minimum falling height satisfies the impulse formula: in It is the acceleration due to gravity. The height of free fall. The impact duration (value ranges from 0.01 to 0.03 s). After step S3 is completed, quartz sand is filled into the gap between the pre-built brick body and the inner wall of the guide pipe, and refractory mortar is covered on the top layer of the pre-built brick body.

9. A construction method for a rapid lining installation fixture for a metallurgical guide pipe according to claim 5, characterized in that, The detached guide tube is then transferred to the baking oven for gradient high-temperature baking based on thermal expansion compensation, using a three-stage heating process: Room temperature heating stage: The temperature is raised from room temperature to 200℃, and the heating rate is controlled within 30℃ / h. The bricks expand slowly to eliminate the pre-laid gaps. Medium-temperature heating stage: The temperature is raised from 200℃ to 600℃, and the heating rate is controlled within 80℃ / h. The brick joint binder gradually carbonizes, and the quartz sand filling layer begins to thermally expand. High-temperature heat preservation stage: heat up to above 800℃ and keep it at that temperature for 2-4 hours. After the heat preservation is completed, cool it down with the furnace.

10. The construction method of the rapid lining tooling for a metallurgical guide pipe according to claim 5, characterized in that, The construction method is used for continuous, assembly-line masonry work on multiple diversion pipes, and also includes the following steps: Step S5: After the masonry tooling in step S4 is left on the ground, the masonry tooling is lifted and moved out, and another set of masonry tooling that has been pre-laid with bricks as described in step S1 is lifted into the work position; Step S6: Use the second set of masonry tools to perform steps S2 to S4 on the next diversion pipe to form a parallel flow operation of "ground pre-masonry - hoisting and separation - tooling removal - recycling". The alternating use of multiple sets of masonry tools decouples the masonry cycle of the diversion pipe from the pre-masonry preparation cycle, enabling continuous operation.

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