Construction method suitable for variable cross-section furnace body maintenance platform

Abstract

The invention relates to a construction method suitable for a variable cross-section furnace body maintenance platform, which comprises the following steps of: S1, preparing accessories such as standard layer rod pieces, variable cross-section rod pieces, temporary cross rods and transfer layer truss pieces according to parameter specifications of a variable cross-section furnace body; s2, proper standard layer rod pieces are selected, and a disc type scaffold is erected in the furnace to the variable cross-section position of the furnace body; s3, selecting variable cross-section vertical rods, connecting the variable cross-section vertical rods to joint positions of the standard layer vertical rods, and assembling variable cross-section cross rods between two adjacent variable cross-section vertical rods to form two independent annular frames; s4, the whole layer of temporary transverse rods are installed between the variable cross-section vertical rods of the two annular frames through bolts and connecting disc insertion holes; s5, transfer layer truss piece installation operation areas are sequentially selected according to preset subareas, temporary transverse rods in the operation areas are released and disassembled, and variable cross-section vertical rods in the operation areas are bidirectionally pulled open towards the furnace wall and the interior of the furnace to form horn mouth structures; s6, a transfer layer truss piece is installed at the horn mouth structure, the temporary transverse rod released in the step S5 is re-installed and reset, and the plug pin is completely pinned tightly in a hammering mode; and S7, the operation steps from the step S5 to the step S6 are repeated till all the transfer layer truss pieces are installed. The platform has the effect of improving the construction efficiency and the space utilization rate of the variable cross-section furnace body maintenance platform.

Description

Technical Field

[0001] This application relates to the field of maintenance platform construction technology, and in particular to a construction method applicable to a variable cross-section furnace maintenance platform. Background Technology

[0002] The digester tank is usually a cylindrical structure with a variable cross-section, which is larger at the bottom and smaller at the top. During operation, it is subjected to complex conditions such as high temperature and high pressure for a long time. Regular maintenance is required to ensure the stability of equipment operation and production safety. Therefore, a maintenance platform needs to be built around the furnace body to meet the basic needs of personnel standing, tool placement and material transportation. At the same time, it needs to be adapted to the size changes of the furnace body's variable cross-section to ensure that the platform fits tightly with the furnace body's outline, providing reliable protection for maintenance operations.

[0003] Currently, the construction of circular maintenance platforms for variable cross-section furnaces in my country generally relies on coupler-type scaffolding. During construction, steel pipes, couplers, scaffold boards, and safety protection accessories of suitable specifications are prepared based on the approximate parameters such as the overall height and outer diameter of the furnace. Then, the platform is erected layer by layer from the ground: steel pipe uprights are erected at preset intervals, and horizontal steel pipes are connected and fixed to the uprights point by point using right-angle couplers and swivel couplers to form the basic frame. When the platform reaches the variable cross-section area of ​​the furnace, the workers measure the actual inner diameter and the slope of the cross-section change on-site, and cut and splice the steel pipes as needed. By adjusting the connection angle of the couplers or using diagonal steel pipe splicing, the frame gradually adapts to the dimensional shrinkage of the furnace from bottom to top, and finally forms a circular maintenance platform surrounding the furnace. At the same time, scaffold boards are fully laid on the frame, guardrails and safety nets are installed, and the overall construction of the maintenance platform is completed.

[0004] However, this traditional construction technique has many shortcomings when dealing with variable cross-section furnace bodies. On the one hand, the components of the coupler-type scaffolding are independent of each other, and all connection nodes need to be bolted one by one during the assembly stage. In addition, the irregularity of the variable cross-section furnace body requires frequent on-site adjustments to the size of the members. Moreover, this process mainly relies on the on-site performance of the laborers. The entire erection process requires repeated adjustments to the position and connection angle of the members to barely adapt to the variable cross-section profile of the furnace body, which directly leads to low construction efficiency and extended construction period. On the other hand, due to the connection characteristics of steel pipes and couplers, it is impossible to plan the arrangement of members in the variable diameter area before construction. After the erection is completed, members often stand in a crisscross pattern at the variable cross-section, which seriously occupies the working passage, making it difficult for inspection, material transportation and maintenance operations to pass, and greatly increasing the complexity of the operation.

[0005] In summary, the existing coupler-type scaffolding construction technology is no longer suitable for the erection requirements of variable cross-section furnace body maintenance platforms. The problems of low construction efficiency and poor space utilization urgently require a construction method specifically for variable cross-section furnace body maintenance platforms. Summary of the Invention

[0006] In order to improve the construction efficiency and space utilization of the variable cross-section furnace body maintenance platform, this application provides a construction method applicable to the variable cross-section furnace body maintenance platform.

[0007] The construction method for a variable cross-section furnace body maintenance platform provided in this application adopts the following technical solution: A construction method for a maintenance platform for a variable cross-section furnace body includes the following steps: S1: Based on the parameters and specifications such as the inner diameter, height, and load requirements of the variable cross-section furnace body, prepare matching accessories such as standard layer members, variable cross-section members, temporary crossbars, and transition layer truss plates. The standard layer members include standard layer uprights and standard layer crossbars, and the variable cross-section members include variable cross-section uprights and variable cross-section crossbars. The standard layer uprights and the variable cross-section uprights are provided with multiple connecting plates at equal intervals along the length direction. S2: Select the appropriate standard layer members from step S1 and erect a disc-type scaffold inside the furnace up to the position of the furnace body's variable cross-section; S3: Select the variable cross-section upright and connect it to the joint position of the standard floor upright. Assemble and fix the variable cross-section crossbar between two adjacent variable cross-section uprights. All the variable cross-section uprights are connected by the variable cross-section crossbar to form two independent ring frames, and the two ring frames are symmetrically arranged on both sides of the working surface. S4: Reserve a plate spacing for installing the conversion layer truss plate. Between the variable cross-section uprights of the two ring frames, select a position with the same height as the standard layer crossbar, and install the entire layer of temporary crossbars through pins and connecting plate holes. S5: Select the installation area of ​​the conversion layer truss piece according to the preset partition, release and disassemble the temporary crossbar in the work area, and use the assembly gap between the variable cross-section upright and the variable cross-section crossbar to pull the variable cross-section upright in the work area to the furnace wall and the furnace in both directions to form a funnel structure. S6: Install the transition layer truss plate at the flared structure where the variable cross-section upright opens. After fixing the transition layer truss plate to the variable cross-section upright, reinstall and reset the temporary crossbar released in step S5, and fully tighten the pin by hammering. S7: Repeat steps S5 to S6 until all the transition layer truss pieces at the variable cross-section location are installed, forming a circular maintenance platform at the variable cross-section location.

[0008] By adopting the above technical solution, during construction, the standard floor uprights are first extended using variable cross-section uprights, and all variable cross-section uprights are then connected to a ring frame using variable cross-section horizontal members, constructing a reliable support foundation for construction in the variable cross-section area. Then, through the overlapping installation and zoned release and disassembly of temporary horizontal members, the overall stability of the scaffolding in non-operational areas is ensured. Furthermore, the assembly gaps between the variable cross-section uprights and horizontal members create a funnel-shaped structure, providing convenient installation space for the transfer floor truss panels. Finally, the temporary horizontal members, after being hammered and tightened, become permanent load-bearing components, completing the lateral support system in the variable cross-section area. Simultaneously, the transfer floor truss panels serve as… Standardized prefabricated components adapted to the variable cross-section parameters of the furnace body eliminate the need for on-site cutting, splicing, or adjustment of connection angles of the members. The construction method of this application replaces traditional on-site adjustments with standardized prefabricated accessories, replaces bolt tightening with quick-connect pins, replaces overall dismantling and modification with zoned operation mode, and replaces oblique overlapping of steel pipes with integrated standard layer truss panels. This shortens the construction cycle of the variable cross-section furnace body maintenance platform, improves construction efficiency, avoids the phenomenon of intersecting members in the variable cross-section area, effectively optimizes the space utilization of the operation channel, and solves the technical problems of low construction efficiency and poor space utilization in the existing construction process.

[0009] Optionally, in step S1, the variable cross-section upright is one plate distance higher than the standard floor upright, and the temporary crossbar has the same size and specifications as the standard floor crossbar.

[0010] By adopting the above technical solution, the height difference of one plate spacing provides sufficient installation space for the truss plate of the transfer layer, ensuring that the truss plate can form a continuous and flat maintenance platform with the standard layer working surface after installation, avoiding unevenness of the working surface due to misalignment of installation height; at the same time, the size and specifications of the temporary crossbar are consistent with those of the standard layer crossbar, which eliminates the need for additional customization of crossbar accessories of different specifications, and ensures the compatibility of the temporary crossbar with the standard layer crossbar and the variable cross-section crossbar.

[0011] Optionally, when erecting the disc scaffold in step S2, wall ties and working platform treads need to be installed simultaneously. The wall ties are reliably anchored to the furnace body, and the working platform treads are fully laid out and fixedly connected to the standard floor horizontal bars, so that the standard floor scaffold forms a complete closed force support area.

[0012] By adopting the above technical solution, wall ties are installed simultaneously and reliably anchored to the furnace body when erecting the disc scaffold. This provides a stable lateral constraint for the standard floor scaffold, resisting the horizontal loads on the scaffold during construction and use. At the same time, the working surface is fully covered with treads and fixedly connected to the horizontal bars of the standard floor, forming a continuous and flat working foundation, which provides basic support for the subsequent installation of variable cross-section members.

[0013] Optionally, in step S4, when installing the temporary crossbar, it is only necessary to overlap the pin with the connector plate socket, without additional hammering to tighten it.

[0014] By adopting the above technical solution, the temporary installation process is simplified in step S4, saving the time of hammering each one for fixation. In the subsequent step S5, when releasing the temporary crossbars in the work area, there is no need to disassemble the fastening structure. Disassembly can be completed simply by pulling out the pin, which reduces the difficulty and time of disassembly and assembly operations and improves the construction efficiency of zoned operations.

[0015] Optionally, in step S5, when releasing and dismantling the temporary crossbars in the work area, it is necessary to maintain the overlapping state of the temporary crossbars in the non-work area.

[0016] By adopting the above technical solution, there is no need to completely stop or dismantle the scaffold. Only the crossbars are released in the work area, so that multiple areas can be carried out in sequence, improving the continuity of construction. At the same time, the remaining temporary crossbars maintain the integrity of the complete ring structure and the lateral restraint capacity, reducing the safety hazards caused by the instability of the scaffold due to the partial removal of temporary crossbars, and ensuring the safety of the scaffold during the zoned operation.

[0017] Optionally, the opening size of the flared structure is 100mm-150mm.

[0018] By adopting the above technical solution, this size range can provide sufficient space for the insertion of the truss panels of the transition layer without the need for secondary cutting and adjustment of the truss panels or uprights; it can also avoid excessive offset or permanent deformation of the variable cross-section uprights due to excessive opening, thus maintaining the structural stability of the ring frame.

[0019] Optionally, the conversion layer truss plate in step S6 includes a truss body. The upper opposite sides of the truss body are provided with fasteners adapted to the connecting holes on the connecting plate, and the lower opposite sides are provided with fasteners connected to the outer surface of the variable cross-section upright. The side of the truss body close to the furnace wall is provided with an upright extension sleeve, and the stress nodes of the truss body are provided with shear-resistant haunches.

[0020] By adopting the above technical solution, the fasteners and couplers are connected to the variable cross-section uprights through plug-in joints, forming a double fixing structure of upper docking and lower clamping. At the same time, it eliminates the need for bolt fastening as in traditional scaffolding, improving construction efficiency. The upright extension sleeve can be connected to the joints of the subsequent standard layer uprights, ensuring the continuous extension of the maintenance platform along the variable cross-section profile of the furnace body. The shear-enhanced structure strengthens the shear and bending load-bearing capacity of the transfer layer truss, enabling the truss to stably bear the loads of personnel, tools, and materials during maintenance operations, thus improving the overall safety of the maintenance platform.

[0021] Optionally, in step S6, when installing the transition layer truss piece, first confirm the installation direction of the transition layer truss piece so that the extension sleeve of the upright faces the side closer to the furnace wall; then connect one side of the truss body to the variable cross-section column through the fastener and the fastener, adjust the spacing of the variable cross-section column by retracting the flared structure inward, and then install the fastener and the fastener on the other side of the truss body to complete the fixing of the transition layer truss piece to the variable cross-section uprights on both sides.

[0022] By adopting the above technical solution, during installation, the installation direction of the transition layer truss panels is first clarified so that the extension sleeves of the uprights face the furnace wall, ensuring the fit between the truss panels and the variable cross-section profile of the furnace body. Then, one side of the truss main body is fixed to the variable cross-section uprights using fasteners and couplings. Next, the spacing is adjusted by retracting the variable cross-section uprights inwards using the allowance of the flared structure. This avoids component damage or connection misalignment caused by forced installation, and the alignment of the truss main body with the variable cross-sections on both sides can be achieved through fine-tuning of the spacing, greatly reducing the difficulty of installation. Finally, the fasteners and couplings on the other side are fixed to connect the truss main body with the variable cross-section uprights as a whole, ensuring uniform load transfer. The entire installation process does not require on-site adjustments by laborers, making the installation steps of the transition layer truss panels uniform and avoiding the problem of disordered alignment of the members in traditional processes.

[0023] In summary, this application includes at least one of the following beneficial technical effects: 1. This construction method replaces traditional on-site cutting and splicing with standardized prefabricated components, replaces bolt tightening with quick-connect pins, and combines with a standardized process of zoned operation and flared installation. This eliminates the tedious procedures of on-site adjustment and repeated dismantling and modification, shortens the erection period, and eliminates the reliance on on-site personnel experience, achieving orderly and efficient construction and improving the construction efficiency of the variable cross-section furnace body maintenance platform. 2. This construction method utilizes the integrated design of the transfer layer truss panels and the regular arrangement of the ring frame to avoid the phenomenon of intersecting members in the variable cross-section area, and reserves a regular working passage and inspection space to ensure smooth personnel passage and material transportation, thereby improving the space utilization rate of the maintenance platform. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the standard layer members and variable cross-section members in the embodiments of this application.

[0025] Figure 2 This is a front view of the conversion layer truss plate in the embodiment of this application.

[0026] Figure 3 This is a front view of the temporary crossbars erected in steps S3 and S4 of this application embodiment.

[0027] Figure 4 This is a top view of the temporary crossbars erected in steps S3 and S4 of this application embodiment.

[0028] Figure 5 This is a front view of the temporary crossbar after it is disassembled and the flared structure is formed in step S5 of this application embodiment.

[0029] Figure 6 This is a top view of the temporary crossbar after it is disassembled and the flared structure is formed in step S5 of this application embodiment.

[0030] Figure 7 This is a front view of the temporary crossbars after the installation of the transfer layer truss plate in step S6 of this application embodiment is completed and tightened in the embodiment.

[0031] Figure 8 This is a process flow diagram of a construction method applicable to a variable cross-section furnace body maintenance platform in the embodiments of this application.

[0032] Explanation of reference numerals in the attached drawings: 01, furnace body; 1, standard layer member; 101, standard layer upright; 102, standard layer horizontal member; 2, variable cross-section member; 21, variable cross-section upright; 22, variable cross-section horizontal member; 3, connecting plate; 31, plate spacing; 4, temporary horizontal member; 5, transfer layer truss plate; 51, truss main body; 52, fastener; 53, fastener; 54, upright extension sleeve; 55, shear-loaded haunch structure; 6, wall tie; 7, working surface tread; 8, ring frame; 9, bell mouth structure. Detailed Implementation

[0033] The following is in conjunction with the appendix Figure 1-7 This application will be described in further detail.

[0034] This application discloses a construction method applicable to a variable cross-section furnace body maintenance platform.

[0035] Reference Figure 1 A construction method for a maintenance platform for a variable cross-section furnace includes the following steps: Step S1: Based on the parameters and specifications such as the inner diameter, variable cross-section height and load requirements of the variable cross-section furnace body 01, prepare matching accessories such as standard layer members 1, variable cross-section members 2, temporary crossbars 4 and transition layer truss pieces 5; Reference Figure 1 , Figure 2 and Figure 3The standard layer member 1 includes standard layer uprights 101 and standard layer horizontal members 102 that make up the disc scaffold. The variable cross-section member 2 includes variable cross-section uprights 21 and variable cross-section horizontal members 22. The standard layer uprights 101 and the variable cross-section uprights 21 are evenly spaced along their length with multiple connecting discs 3. The distance between two connecting discs 3 is called the disc spacing. The variable cross-section uprights 21 are higher than the standard layer uprights 101 by a disc spacing 31. In this embodiment, the standard layer uprights 101 have three disc spacings 31 and the variable cross-section uprights 21 have four disc spacings. The height difference of one disc spacing provides sufficient installation space for the transition layer truss plate 5. The size and specifications of the temporary horizontal members 4 are consistent with those of the standard layer horizontal members 102 to ensure the compatibility of the temporary horizontal members 4 with the standard layer horizontal members 102 and the variable cross-section horizontal members 22. Reference Figure 2 The transition layer truss plate 5 includes a truss body 51. On the upper part of the truss body 51, opposite sides along the length direction, are installed fasteners 52 that are compatible with the connecting holes on the connecting plate 3. On the lower part, opposite sides along the length direction, are fasteners 53 that connect to the outer surface of the variable cross-section upright 21. The fasteners 52, fasteners 53, and connecting plate 3 are all existing technologies commonly used in the scaffolding field, and their specific structures will not be described in detail in this embodiment. On the side of the truss body 51 closest to the furnace wall, an upright extension sleeve 54 is installed. The upright extension sleeve 54 can connect with the joints of the subsequently extended standard layer uprights 101, ensuring the continuous extension of the maintenance platform along the variable cross-section profile of the furnace body 01. Shear-resistant haunch structures 55 are installed at the stress nodes of the truss body 51, thereby enhancing the shear and bending bearing capacity of the transition layer truss plate 5, enabling the truss body 51 to stably withstand the loads of personnel, tools, and materials during maintenance operations, and improving the overall safety of the maintenance platform.

[0036] Reference Figure 3 Step S2: Select a suitable standard layer member 1 from step S1 and erect a disc-type scaffold inside the furnace up to the variable cross-section position of the furnace body 01. During the erection process, wall ties 6 and working surface treads 7 need to be installed simultaneously. The wall ties 6 are reliably anchored to the furnace body 01 to provide a stable lateral constraint for the standard layer frame and resist the horizontal load of the frame during construction and use. The working surface treads 7 are fully laid and fixedly connected to the standard layer horizontal bar 102, so that the standard layer scaffold forms a complete closed force support area, providing a basic support for the subsequent installation of variable cross-section members 2.

[0037] Reference Figure 3 and Figure 4 Step S3: Select the variable cross-section upright 21 and connect it to the joint position of the standard floor upright 101. Assemble and fix the variable cross-section crossbar 22 between two adjacent variable cross-section uprights 21. All variable cross-section uprights 21 are connected by the variable cross-section crossbar 22 to form two independent ring frames 8, and the two ring frames 8 are symmetrically arranged on both sides of the working surface.

[0038] Reference Figure 5 and Figure 6 Step S4: Reserve a plate spacing 31 for installing the conversion layer truss plate 5. Between the variable cross-section uprights 21 of the two annular frames 8, select a position with the same height as the standard layer horizontal bar 102 to install the entire layer temporary horizontal bar 4. In this embodiment, it is at the third plate spacing 31 of the variable cross-section upright 21. When installing the temporary horizontal bar 4, it is only necessary to overlap the pin with the insertion hole of the connecting plate 3 without additional hammering to tighten it. This simplifies the temporary installation process, saves the time spent hammering to fix each one, and facilitates the repeated disassembly and assembly of the temporary horizontal bar 4 in the future.

[0039] Reference Figure 6 and Figure 7 Step S5: Select the installation work area of ​​the conversion layer truss piece 5 in sequence according to the preset partitions, release and dismantle the temporary crossbars 4 in the work area, and at the same time, keep the temporary crossbars 4 in the unworked area in an overlapping state. Maintain the integrity of the complete ring structure and the lateral constraint capacity through the remaining temporary crossbars 4, reduce the safety hazards caused by the instability of the frame due to the partial dismantling of the temporary crossbars 4, and ensure the safety of the frame during the partitioned operation. Reference Figure 6 and Figure 7 By utilizing the assembly gap between the variable cross-section uprights 21 and the variable cross-section crossbars 22, the variable cross-section uprights 21 in the working area are pulled open in both directions towards the furnace wall and the furnace interior, forming a flared structure 9 with an opening size of 100mm-150mm. This size range can provide sufficient embedding and operation space for the conversion layer truss plate 5, eliminating the need for secondary cutting and adjustment of the conversion layer truss plate 5 or the variable cross-section uprights 21, thus shortening the construction cycle of the variable cross-section furnace body 01 maintenance platform and improving construction efficiency; it can also avoid excessive offset or permanent deformation of the variable cross-section uprights 21 due to excessive opening, maintaining the structural stability of the ring frame 8. Reference Figure 6 and Figure 7 Step S6: Install the transition layer truss plate 5 at the flared structure 9 of the variable cross-section upright 21. During installation, first confirm the installation direction of the transition layer truss plate 5 so that the upright extension sleeve 54 faces the side closer to the furnace wall. Then, connect one side of the truss body 51 to the variable cross-section upright through the fastener 52 and fastener 53. Specifically, fasten the fastener 52 to the connecting hole on the connecting plate 3, and install the fastener 53 on the outer surface of the variable cross-section upright 21. After the installation of one side is completed, retract the flared structure 9 inward to adjust the spacing of the variable cross-section uprights. Then, install the fastener 52 and fastener 53 on the other side of the truss body 51 to complete the fixing of the transition layer truss plate 5 to the two variable cross-section uprights 21. After the upper fastener 52 is connected, it forms the transition layer working surface with the scaffold body. After the lower fastener 53 is connected, it improves the shear and bending resistance of the transition layer working surface. Finally, the temporary crossbar 4 released in step S5 is reinstalled and reset, and the pin is fully tightened by hammering. At this point, the temporary crossbar 4 is transformed into a permanent load-bearing component, completing the transverse support system of the variable cross-section area.

[0040] Step S7: Repeat steps S5 to S6 until all the transition layer truss pieces 5 at the variable cross-section location are installed, forming a circular maintenance platform at the variable cross-section location.

[0041] The implementation principle of a construction method applicable to a variable cross-section furnace body maintenance platform according to an embodiment of this application is as follows: During construction, the standard floor uprights 101 are first extended using the variable cross-section uprights 21, and all the variable cross-section uprights 21 are connected to the ring frame 8 through the variable cross-section crossbars 22, thus constructing a reliable support foundation for construction in the variable cross-section area; then, through the overlapping installation and zoned release and disassembly of the temporary crossbars 4, the overall stability of the frame in the non-operation area is ensured, and the assembly gap between the variable cross-section uprights 21 and the variable cross-section crossbars 22 is used to open up the funnel structure 9, providing convenient installation and operation space for the transfer layer truss panels 5. Finally, the temporary crossbars 4 are hammered and tightened, transforming into permanent load-bearing components, thus completing the variable cross-section area. The transverse support system, along with the conversion layer truss plate 5 serving as a standardized prefabricated component adapted to the variable cross-section parameters of the furnace body 01, eliminates the need for on-site cutting, splicing, or adjustment of connection angles for the members. The construction method of this application replaces traditional on-site adjustments with standardized prefabricated components, replaces bolt tightening with quick-connect pins, replaces overall dismantling and modification with a zoned operation mode, and replaces oblique overlapping of steel pipes with integrated standard layer truss plates. This shortens the erection cycle of the maintenance platform for the variable cross-section furnace body 01, improves construction efficiency, avoids the phenomenon of intersecting members in the variable cross-section area, effectively optimizes the space utilization of the work passage, and solves the technical problems of low construction efficiency and poor space utilization in existing construction processes.

[0042] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A construction method suitable for a maintenance platform for a variable cross-section furnace body, characterized in that, Includes the following steps: S1: Based on the parameters and specifications such as the inner diameter, height and load requirements of the variable cross-section furnace body, prepare matching accessories such as standard layer members (1), variable cross-section members (2), temporary crossbars (4) and transition layer truss pieces (5). The standard layer members (1) include standard layer uprights (101) and standard layer crossbars (102). The variable cross-section members (2) include variable cross-section uprights (21) and variable cross-section crossbars (22). The standard layer uprights (101) and the variable cross-section uprights (21) are provided with multiple connecting plates (3) at equal intervals along the length direction. S2: Select the appropriate standard layer rod (1) from step S1 and erect a disc scaffold inside the furnace to the variable cross-section position of the furnace body (01); S3: Select the variable cross-section upright (21) and connect it to the joint position of the standard floor upright (101). Assemble the variable cross-section crossbar (22) between two adjacent variable cross-section uprights (21) and fix it. All the variable cross-section uprights (21) are connected by the variable cross-section crossbar (22) to form two independent ring frames (8), and the two ring frames (8) are symmetrically arranged on both sides of the working surface. S4: Reserve a plate spacing (31) for installing the conversion layer truss plate (5). Between the variable cross section uprights (21) of the two ring frames (8), select a position with the same height as the standard layer crossbar (102), and install the entire layer of temporary crossbars (4) through the pin and the connecting plate (3) insertion hole. S5: Select the installation area of ​​the conversion layer truss piece (5) in sequence according to the preset partition, release and disassemble the temporary crossbar (4) in the work area, and use the assembly gap between the variable cross-section upright (21) and the variable cross-section crossbar (22) to pull the variable cross-section upright (21) in the work area to the furnace wall and the furnace in both directions to form a funnel structure (9). S6: Install the transition layer truss piece (5) at the flared structure (9) of the variable cross-section upright (21). After fixing the transition layer truss piece (5) to the variable cross-section upright (21), reinstall and reset the temporary crossbar (4) released in step S5, and use a hammering method to fully tighten the pin. S7: Repeat steps S5 to S6 until all the transition layer truss pieces (5) at the variable cross-section position are installed to form a circular maintenance platform at the variable cross-section.

2. The construction method for a variable cross-section furnace body maintenance platform according to claim 1, characterized in that, In step S1, the variable cross-section upright (21) is higher than the standard floor upright (101) by a plate spacing (31), and the temporary crossbar (4) has the same size and specifications as the standard floor crossbar (102).

3. The construction method for a variable cross-section furnace body maintenance platform according to claim 1, characterized in that, When erecting the disc scaffold in step S2, the wall tie (6) and the working surface tread (7) need to be installed simultaneously. The wall tie (6) is reliably anchored to the furnace body (01). The working surface tread (7) is fully laid and fixedly connected to the standard floor crossbar (102), so that the standard floor scaffold forms a complete closed force support area.

4. The construction method for a variable cross-section furnace body maintenance platform according to claim 1, characterized in that, In step S4, when installing the temporary crossbar (4), it is only necessary to overlap the pin with the socket of the connecting plate (3) without additional hammering to tighten it.

5. The construction method for a variable cross-section furnace body maintenance platform according to claim 1, characterized in that, In step S5, when releasing and dismantling the temporary crossbar (4) in the work area, it is necessary to keep the temporary crossbar (4) in the non-work area in an overlapping state.

6. The construction method for a variable cross-section furnace body maintenance platform according to claim 1, characterized in that, The opening size of the flared structure (9) is 100mm-150mm.

7. The construction method for a variable cross-section furnace body maintenance platform according to claim 1, characterized in that, The conversion layer truss plate (5) in step S6 includes a truss body (51). The upper two opposite sides of the truss body (51) are provided with fasteners (52) that are adapted to the connecting holes on the connecting plate (3). The lower two opposite sides are provided with fasteners (53) that are connected to the outer surface of the variable cross section upright (21). The side of the truss body (51) close to the furnace wall is provided with an upright extension sleeve (54). The stress nodes of the truss body (51) are provided with shear armhole structures (55).

8. A construction method for a variable cross-section furnace body maintenance platform according to claim 7, characterized in that, In step S6, when installing the transition layer truss piece (5), first confirm the installation direction of the transition layer truss piece (5) so that the extension sleeve (54) of the upright faces the side closer to the furnace wall; then connect one side of the truss body (51) to the variable cross-section column through the fastener (52) and the fastener (53), adjust the spacing of the variable cross-section column by retracting the flared structure (9) inward, and then install the fastener (52) and the fastener (53) on the other side of the truss body (51) to complete the fixing of the transition layer truss piece (5) to the variable cross-section uprights (21) on both sides.

Images