Construction method for replacing whole belt of blast furnace shell

Abstract

The invention discloses a construction method for replacing a whole belt of a blast furnace shell. The construction method comprises the steps that construction preparation is conducted, an auxiliary platform is erected, and a hanging scaffold operation platform is erected in a blast furnace; a simple operation platform is installed on an original bustle pipe platform outside a blast furnace and used for construction and installation of a furnace shell. An oxygen blowing pipe oxygen blowing method is adopted for dismantling, the topmost layer of local furnace shell is dismantled, and the area of the local furnace shell is specifically one sixth of the area of the furnace shell needing to be dismantled; the furnace shell is transferred and hoisted, specifically, a set of electric chain hoists are installed on a supporting structure arranged around the blast furnace shell in advance, when the partial furnace shell is replaced, a hoisting steel wire rope is connected with a water pipe hole in the new furnace shell through a shackle, and the hoisting position of the new furnace shell is determined; fourthly, the remaining local furnace shell is sequentially replaced from top to bottom, welded and reinforced; checking and accepting after the inspection is qualified, and dismounting the auxiliary platform and the electric chain hoist. According to the method, the whole section of furnace shell is locally detached and replaced, the hoisting pressure existing in an existing method can be effectively reduced, and the working safety is improved.

Description

Technical Field

[0001] The invention relates to the technical field of steel structure installation, in particular to a construction method for replacing the entire shell of a blast furnace. Background Art

[0002] The blast furnace is the most important link in the ironmaking process. During the long-term production process, the furnace shell in the high-temperature zone is prone to deformation under long-term high-temperature conditions, and the furnace shell needs to be replaced as a whole belt. Before removing the furnace shell, the upper and lower layers of the furnace shell to be removed need to be reinforced to avoid tilting of the upper and middle blast furnace bodies during the replacement of the furnace shell. The existing furnace shell replacement plan is to remove the whole belt, and the whole belt lifting technology is currently a more common method for replacing blast furnace shells. The replacement of the blast furnace shell as a whole belt is a complex and technically demanding project. Its purpose is to extend the service life of the blast furnace, improve production efficiency and ensure safe operation. For example, in the renovation of a hot blast furnace in Panzhihua Iron and Steel, the method of lifting the furnace shell as a whole belt was adopted. It was pre-assembled and welded into a whole belt on an elevated platform, and then hoisted into place in sections using a tower crane. This method significantly reduced on-site construction time and the risk of high-altitude operations.

[0003] However, in the actual replacement process, the replacement of the entire blast furnace shell may cause the blast furnace to tilt and collapse, resulting in a safety accident. Therefore, developing a method that can effectively reduce the blast furnace tilting problem during the shell replacement process is one of the important issues that need to be solved. Summary of the Invention

[0004] In view of the above problems existing in the prior art, the object of the present invention is to provide a construction method for replacing the entire belt of a blast furnace shell.

[0005] To solve the above problems, the present invention adopts the following technical solution: a construction method for replacing the entire belt of a blast furnace shell, comprising the steps of:

[0006] Step 1: Construction preparation: set up an auxiliary platform and a hanging plate operating platform inside the blast furnace; install a simple operating platform on the original surrounding pipe platform outside the blast furnace for the construction and installation of the furnace shell;

[0007] Step 2: Use oxygen blowing method to dismantle the furnace shell from top to bottom, and dismantle the partial furnace shell from top to bottom. The partial furnace shell is specifically one-sixth of the furnace shell area to be dismantled;

[0008] Step 3: Transport and hoist the furnace shell. A set of electric chain hoists is pre-installed on the support structure surrounding the blast furnace shell. When replacing the partial furnace shell described in step 2, the hoisting wire rope is connected to the water pipe hole on the new furnace shell through a shackle to adjust the hoisting position of the new furnace shell.

[0009] Step 4: Remove and replace the remaining partial furnace shell from top to bottom and reinforce it by welding;

[0010] Step 5: After passing the inspection, the project is handed over for acceptance and the auxiliary platform and electric chain hoist are removed.

[0011] The hoisting described in step 3 specifically includes the following steps:

[0012] S31. Install an electric chain hoist above the position of the removed furnace shell. Use the simple operating platform to coordinate the pre-installed electric chain hoist with the newly installed electric chain hoist. Use wire ropes to hoist the new furnace shell to the designated position. Use clips and wedges to clamp and secure the upper part of the new furnace shell. Operators on the hoisting platform use wire ropes to adjust the position of the new furnace shell so that it matches the position of the old furnace shell above.

[0013] S32. After confirming that the upper portion of the newly installed furnace shell corresponds to the position of the old furnace shell above, control the electric chain hoist to further correct its position;

[0014] S33. Simple operating platform: Coordinate the preset electric chain hoist with the newly installed electric chain hoist, use clips and wedges to clamp and fix the lower part of the new furnace shell. The staff adjusts the lower position of the new furnace shell on the hoisting platform to match the position of the old furnace shell below, thereby completing the hoisting of the new furnace shell and the installation and positioning of the upper and lower parts.

[0015] The dismantling described in step 2 is specifically to push the dismantled furnace shell into the furnace and use an excavator to clean it to the iron-making yard.

[0016] The hoisting wire rope described in step 3 is connected to the water pipe hole on the new furnace shell through the shackle, and the new furnace shell is hoisted. After the hoisting is completed, the wire rope is pulled out from the water pipe hole.

[0017] The newly installed furnace shell is fixed to the old furnace shell above it by a clamping ring; specifically, the clamping ring passes through the water pipe holes of the new furnace shell and the old furnace shell respectively, and is fixed at the end by a fixing piece to fix the new furnace shell to the old furnace shell.

[0018] The simple operating platform is constructed using 20a and 16a channel steels.

[0019] The replacement positions of the new furnace shells are staggered.

[0020] The simple operating platform is paved with 4mm patterned plates.

[0021] Compared with the prior art, the beneficial technical effects of the present invention are:

[0022] 1. This application replaces the existing method of removing and replacing the entire belt with the partial removal and replacement of the entire furnace shell, which can effectively reduce the lifting pressure existing in the existing method, and basically avoid the occurrence of dangers such as furnace shell tilting, thereby improving work safety;

[0023] 2. This application uses a top-down approach to gradually dismantle and replace the old furnace shell, thereby ensuring the stability of the base structure of the furnace shell during the replacement process as much as possible, further improving the safety of the replacement operation;

[0024] 3. The newly installed furnace shell of the present application is fixed to the old furnace shell arranged above it by a clamping ring; specifically, the clamping ring passes through the water pipe holes of the new furnace shell and the old furnace shell respectively, and is fixed at the end by a fixing piece. The fixed connection between the new furnace shell and the old furnace shell can effectively improve the overall structural stability of the furnace shell. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a process flow chart of replacing the entire belt of the furnace shell according to the embodiment of the application;

[0026] Figure 2 This is a schematic diagram of the structure of a simple platform set up in an embodiment of the application;

[0027] Figure 3 This is a schematic diagram of the new furnace shell installation structure of the embodiment of the present application;

[0028] Figure 4 This is a schematic diagram of the connection structure between the new furnace shell and the old furnace shell in an embodiment of the present application;

[0029] In the picture, 1. New furnace shell, 2. Electric chain hoist, 3. Clip, 4. Old furnace shell, 5. Snap ring, 21. Wire rope, 22. Wedge, 23. Clip. DETAILED DESCRIPTION

[0030] The technical solution of the present invention will be further described in detail below with reference to the embodiments and drawings.

[0031] Example

[0032] See also Figure 1 A construction method for replacing the entire belt of a blast furnace shell comprises the following steps:

[0033] Step 1: Set up the auxiliary platform:

[0034] Before maintenance, a hoisting platform is set up inside the blast furnace;

[0035] Before dismantling the furnace shell, a simple operation platform 6 is installed on the original surrounding pipe platform outside the blast furnace to facilitate the installation and construction of the furnace shell. Figure 2 As shown, in some embodiments, the simple operation platform 6 is made of main beams 20a and 16a channel steel, and 4mm patterned plates are laid on the platform; the simple operation platform 6 is moved up and down by borrowing the original platform. For example, in some embodiments, the simple platform is 8 meters wide and 5.75 meters long, extending 2.3 meters from the original platform, and the simple operation platform 6 is moved up and down by borrowing the original platform;

[0036] Step 2: Use oxygen blowing with an oxygen lance to dismantle the furnace shell from top to bottom. The partial furnace shell is specifically one-sixth of the furnace shell area to be dismantled. In some embodiments, the dismantling is to push the dismantled furnace shell into the furnace and use an excavator to clean it to the iron-making yard.

[0037] Step 3: transport and hoist the furnace shell. Install a set of chain electric hoists 2 on the supporting structure around the blast furnace shell in advance. When replacing the partial furnace shell described in step 2, the hoisting wire rope 21 is connected to the water pipe hole on the new furnace shell 1 through the shackle to determine the hoisting position of the new furnace shell 1. For example, install 12 chain electric hoists 2 (with a load capacity of 5T or 10T) on the supporting structure around the blast furnace shell with a diameter of 26m in advance, and install two 5T hand hoists or chain electric hoists on the upper part of the new furnace shell 1, that is, on the old furnace shell 4. The hoisting wire rope 21 is connected to the water pipe hole on the new furnace shell 1 through the shackle to adjust the hoisting position of the new furnace shell, such as Figure 3 As shown;

[0038] Step 4: Remove and replace the remaining partial furnace shell from top to bottom and reinforce it by welding. In some embodiments, in order to further improve the welding effect, multi-layer and multi-pass welding joints are used, and segmented jump welding is used to reduce heat concentration; in some preferred embodiments, it can be preheated to 150~200℃ before welding, and slowly cooled after welding to eliminate stress, so as to further improve the welding effect.

[0039] Step 5: After passing the inspection, the project is handed over for acceptance and the auxiliary platform and electric chain hoist 2 are removed.

[0040] In some embodiments, the hoisting described in step 3 specifically includes the steps of:

[0041] S31. Install the chain electric hoist 2 above the position of the dismantled furnace shell. The simple operating platform 6 matches the preset chain electric hoist 2 with the newly installed chain electric hoist 2. Use the wire rope 21 to hoist the new furnace shell 1 to the specified position. Use the clamp 3 and the wedge 22 to clamp and fix the upper part of the new furnace shell 1. The operator adjusts the position of the new furnace shell 1 on the hoisting platform to match the position of the old furnace shell 4 above. Specifically, the clamp ring 5 passes through the water pipe holes of the new furnace shell 1 and the old furnace shell 4 respectively, and is fixed at the end by a fixing piece. The new furnace shell 1 and the old furnace shell 4 are fixedly connected, as shown in FIG. Figure 4 As shown;

[0042] S32, after confirming that the upper part of the newly installed furnace shell corresponds to the position of the upper furnace shell, control the electric chain hoist 2 to further correct it;

[0043] S33, the simple operating platform 6 matches the preset electric chain hoist 2 with the newly installed electric chain hoist 2, and uses the clip 3 and the wedge 22 to clamp and fix the lower part of the new furnace shell 1. The staff adjusts the lower position of the new furnace shell 1 on the hoisting platform to match the position of the old furnace shell 4 below, thereby completing the hoisting of the new furnace shell 1.

[0044] In some preferred embodiments, the partial replacement positions of the furnace shell are staggered, which can further ensure the stability of the overall structure of the furnace shell during the replacement process.

[0045] In actual operation, there are cases where a 5T electric chain hoist is not enough on site. Further explanation is needed. Only electric chain hoists with a capacity of 5T or above can be used as a replacement. The efficiency of the hand chain hoist is too low. It can be used for fine-tuning during the installation and adjustment stage.

[0046] In some embodiments, the simple operating platform 6 is constructed using materials such as steel 20a, 16a channel steel, and can also be replaced by larger-sized profiles or 355B steel.

[0047] Finally, it is necessary to point out here that the above is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by any technician familiar with the present invention within the technical scope disclosed by the present invention should be covered within the scope of protection of the present invention.

Claims

1. A construction method for replacing the entire belt of a blast furnace shell, characterized in that: Including steps: Step 1: Construction preparation, set up an auxiliary platform, set up a hanging plate operation platform inside the blast furnace; install a simple operation platform (6) on the original surrounding pipe platform outside the blast furnace for construction and installation of the furnace shell; Step 2: Use oxygen blowing method to dismantle the furnace shell from top to bottom, and dismantle the partial furnace shell from top to bottom. The partial furnace shell is specifically one-sixth of the furnace shell area to be dismantled; Step 3: transporting and hoisting the furnace shell. A set of electric chain hoists (2) are pre-installed on the support structure provided around the blast furnace shell. When replacing the partial furnace shell in step 2, the hoisting wire rope (21) is connected to the water pipe hole on the new furnace shell (1) through the shackle to adjust the hoisting position of the new furnace shell (1); Step 4: Remove and replace the remaining partial furnace shell from top to bottom and reinforce it by welding; Step 5: After passing the inspection, the project is handed over for acceptance and the auxiliary platform and the electric chain hoist (2) are removed.

2. A construction method for replacing the entire blast furnace shell according to claim 1, characterized in that: The hoisting described in step 3 specifically includes the following steps: S31. Install a chain electric hoist (2) above the position of the removed furnace shell. The simple operation platform (6) matches the preset chain electric hoist (2) with the newly installed chain electric hoist (2). Use the wire rope (21) to lift the new furnace shell (1) to the designated position. Use the clamp (3) and the wedge (22) to clamp and fix the upper part of the new furnace shell (1). The operator adjusts the position of the new furnace shell (1) through the wire rope (21) on the hoisting platform to match the position of the old furnace shell (4) above. S32, after confirming that the upper portion of the newly installed furnace shell corresponds to the position of the old furnace shell (4), the electric chain hoist (2) is controlled to further correct the position; S33, the simple operation platform (6) matches the preset electric chain hoist (2) with the newly installed electric chain hoist (2), and uses the clamp (3) and the wedge (22) to clamp and fix the lower part of the new furnace shell (1). The staff adjusts the position of the lower part of the new furnace shell (1) on the hoisting platform (6) so that it matches the position of the old furnace shell (4) below, thereby completing the hoisting of the new furnace shell (1) and the installation and positioning of the upper and lower parts.

3. A construction method for replacing the entire blast furnace shell according to claim 1, characterized in that: The dismantling described in step 2 is specifically to push the dismantled furnace shell into the furnace and use an excavator to clean it to the iron-making yard.

4. A construction method for replacing the entire blast furnace shell according to claim 1, characterized in that: In step 3, the hoisting wire rope (21) is connected to the water pipe hole on the new furnace shell (1) through the shackle, and the new furnace shell (1) is hoisted. After the hoisting is completed, the wire rope is pulled out from the water pipe hole.

5. The construction method for replacing the entire blast furnace shell according to claim 1, characterized in that: The newly installed furnace shell is fixed to the old furnace shell (4) arranged above it via a clamping ring (5); specifically, the clamping ring (5) passes through the water pipe holes of the new furnace shell (1) and the old furnace shell (4), respectively, and is fixed at the end by a fixing piece, so that the new furnace shell (1) and the old furnace shell (4) are fixedly connected.

6. A construction method for replacing the entire belt of a blast furnace shell according to claim 1, characterized in that: The simple operation platform (6) is constructed using 20a and 16a channel steels.

7. A construction method for replacing the entire belt of a blast furnace shell according to claim 1, characterized in that: The replacement position of the new furnace shell (1) is staggered.

8. A construction method for replacing the entire belt of a blast furnace shell according to claim 1, characterized in that: A 4mm patterned plate is laid on the simple operating platform (6).

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