Method for replacing whole belt of blast furnace shell without temporary measures

Abstract

The invention relates to a method for replacing a whole belt of a blast furnace shell without temporary measures, which comprises the following steps of: symmetrically dismounting and mounting the whole belt of the blast furnace shell in blocks, sequentially and symmetrically constructing to replace the furnace shell, and welding an upper circumferential weld and a lower circumferential weld on a first new furnace shell and a second new furnace shell which are replaced, and the third new furnace shell, the fourth new furnace shell, the fifth new furnace shell and the sixth new furnace shell are welded with vertical welding seams between the two replaced adjacent new furnace shells, then upper circumferential welding seams and lower circumferential welding seams of the new furnace shells are welded until all the split old furnace shells of the whole-belt furnace shell are replaced with the new furnace shells, and whole-belt replacement of the blast furnace shell is completed. The method has the beneficial effects that large temporary measures are not needed to assist in construction, the whole belt replacement speed of the blast furnace shell is increased, the operation efficiency is improved, the replacement time is shortened, the overall size and equipment of the blast furnace are not affected, the replacement cost is saved, and the safety of replacement operation is guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of metallurgical steel structure construction, and in particular to a method for replacing the entire belt of a blast furnace shell without using temporary measures. Background Art

[0002] At present, in the iron-making production process, affected by the production process, the furnace shell of the blast furnace body hearth is easily damaged due to complex working conditions and high temperature, which eventually leads to unsafe blast furnace production and has to be replaced and repaired.

[0003] Traditionally, the replacement of blast furnace shells is mostly done as a whole. In order to ensure the construction quality, a large blast furnace needs to use a lot of temporary measures to replace the entire belt shell of the blast furnace to be replaced. The upper part of the blast furnace shell to be replaced needs to be lifted as a whole and fixed on the furnace frame. After the shell is replaced, it is welded in a free state, and the temporary measures are removed after the shell is replaced and welded. Alternatively, the shell, cooling equipment, etc. are dismantled as a whole from top to bottom, and the whole shell is spliced ​​and replaced. This replacement method requires the reinstallation of a new shell, cooling equipment, etc., with a long replacement cycle, high replacement cost, complicated technology, difficult construction, and difficult to grasp the structural size of the blast furnace, which has many impacts on the subsequent production of the blast furnace. Summary of the invention

[0004] In order to overcome the shortcomings of the prior art, the present invention provides a method for replacing a whole belt of a blast furnace shell without adopting temporary measures. The whole belt of the blast furnace shell is symmetrically dismantled and installed in blocks, so as to speed up the replacement of the whole belt of the blast furnace shell. No large-scale temporary measures are required to assist the construction, thereby improving the operation efficiency, shortening the replacement time, and the overall size and equipment of the blast furnace are not affected, thus saving the replacement cost and ensuring the safety of the replacement operation.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A method for replacing the entire belt of a blast furnace shell without using temporary measures, the method comprising the following steps:

[0007] S1. Split the entire furnace shell into several parts along the circumference and radial direction, confirm the splitting cutting line on the furnace shell, and mark the reference line;

[0008] S2. Replace the furnace shell in a symmetrical manner, and use gas cutting to remove the most severely damaged area as the first piece of the old furnace shell to be replaced;

[0009] S3. Replace the old furnace shell with a new furnace shell according to its structural form. After the new furnace shell is in place, weld the upper and lower circumferential welds of the first new furnace shell to be replaced;

[0010] S4, determining the furnace shell at the diameter symmetrical position of the first old furnace shell as the second old furnace shell, removing the second old furnace shell by the same cutting method, and repeating the method of step S3 to weld the upper and lower girth welds of the replaced second new furnace shell;

[0011] S5, repeat the replacement methods of S2 to S4 in the order of symmetrical replacement, replace the third old furnace shell on the adjacent side of the first old furnace shell and the fourth old furnace shell at the symmetrical position of the third old furnace shell, after the third new furnace shell and the fourth new furnace shell are in place, first weld the vertical weld between the two adjacent new furnace shells that have been replaced, and then weld the upper and lower girth welds of the new furnace shell;

[0012] S6, repeat the replacement method of S5, replace the fifth old furnace shell adjacent to the other side of the first old furnace shell and the sixth old furnace shell symmetrically located to the fifth old furnace shell, after the fifth new furnace shell and the sixth new furnace shell are in place, first weld the vertical weld between the two adjacent new furnace shells, and then weld the upper and lower girth welds of the new furnace shell;

[0013] S7, repeat the replacement method of S5 to S6, and replace the old furnace shells at the adjacent two side positions and the two side symmetrical positions in turn, until all the old furnace shells that have been split into a whole strip of furnace shells are replaced with new furnace shells, and the replacement of the whole strip of blast furnace shells is completed.

[0014] Furthermore, the number of parts into which the whole furnace shell is split in step S1 is an even number.

[0015] Furthermore, the entire furnace shell in step S1 is split symmetrically according to the original welds of the furnace shell.

[0016] Furthermore, the vertical weld and the girth weld are welded by first welding the inner groove weld of the entire furnace shell and then welding the outer groove weld.

[0017] Furthermore, the girth weld and the vertical weld are welded by segmented back-welding.

[0018] Furthermore, after the vertical weld and the girth weld are welded for one layer, the weld area is tapped using a stress relief instrument.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1. The whole belt of blast furnace shell is replaced by dismantling and installing in blocks. The shell is replaced symmetrically in sequence to reduce the construction difficulty, and the damaged whole belt area is replaced in a centralized manner to improve the replacement efficiency and shorten the replacement time. The whole belt is replaced in different areas without affecting the overall size of the blast furnace and the connection status of the equipment, thus ensuring the subsequent production efficiency, saving a lot of construction costs, and ensuring the quality and safety of the construction work.

[0021] 2. Replace symmetrically in sequence to reduce stress concentration during replacement, reduce deformation during the process, reduce the difficulty of welding, reduce the risk of welding deformation, improve welding quality, improve welding effect, and ensure the quality of construction work. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the replacement sequence of the entire belt of the blast furnace shell according to the present invention.

[0023] Figure 2 It is a schematic diagram of the segmented back welding of the vertical seam of the furnace shell according to the present invention.

[0024] Figure 3 This is a schematic diagram of the furnace shell annular seam segmented welding back according to the present invention

[0025] In the figure: 1. The first new furnace shell; 2. The second new furnace shell; 3. The third new furnace shell; 4. The fourth new furnace shell; 5. The fifth new furnace shell; 6. The sixth new furnace shell; 7. The first section of desoldering; 8. The second section of desoldering; 9. The third section of desoldering. DETAILED DESCRIPTION

[0026] The specific embodiments of the present invention are further described below:

[0027] like Figure 1-Figure 3 As shown, a method for replacing the entire belt of a blast furnace shell without using temporary measures, the method for replacing the entire belt of a blast furnace shell comprises the following steps:

[0028] S1. The whole furnace shell is divided into 6 pieces. According to the original weld seams of the furnace shell, the furnace shell is dismantled and installed symmetrically. Before dismantling the furnace shell, the cutting line should be confirmed on the furnace shell to be dismantled, and the reference line should be marked;

[0029] S2. Replace the furnace shell in a symmetrical manner, and use gas cutting to remove the most severely damaged area as the first piece of the old furnace shell to be replaced;

[0030] S3, replacing the old furnace shell with a new furnace shell according to its structural form, installing the new furnace shell at the location where the old furnace shell was removed, and after the new furnace shell is in place, welding the upper and lower circumferential welds of the first new furnace shell 1 that is replaced;

[0031] S4, determining the furnace shell at the diameter symmetrical position of the first old furnace shell as the second old furnace shell to be replaced, removing the second old furnace shell by the same cutting method, and repeating the method of step S3 to weld the upper and lower girth welds of the second new furnace shell 2 to be replaced;

[0032] S5, in the order of symmetrical replacement, repeat the replacement method of S2 to S4, replace the third old furnace shell on the adjacent side of the first old furnace shell and the fourth old furnace shell at the symmetrical position of the third old furnace shell, after the third new furnace shell 3 and the fourth new furnace shell 4 are in place, first weld the vertical weld between the two adjacent new furnace shells that have been replaced, and then weld the upper and lower girth welds of the new furnace shell, the welding order of the third new furnace shell 3 is to first weld the vertical weld between the first new furnace shell 1 and the third new furnace shell 3, and then weld the upper and lower girth welds of the third new furnace shell 3; the welding order of the fourth new furnace shell 4 is to first weld the vertical weld between the second new furnace shell 2 and the fourth new furnace shell 4, and then weld the upper and lower girth welds of the fourth new furnace shell 4;

[0033] S6, repeat the replacement method of S5, replace the fifth old furnace shell on the other side adjacent to the first old furnace shell and the sixth old furnace shell in the symmetrical position of the fifth old furnace shell, after the fifth new furnace shell and the sixth new furnace shell are in place, first weld the vertical weld between the two adjacent new furnace shells, and then weld the upper and lower girth welds of the new furnace shell, the welding sequence of the fifth new furnace shell 5 is to first weld the vertical weld between the first new furnace shell 1 and the fifth new furnace shell 5, then weld the vertical weld between the fourth new furnace shell 4 and the fifth new furnace shell 5, and then weld the upper and lower girth welds of the fifth new furnace shell 5; the welding sequence of the sixth new furnace shell 6 is to first weld the vertical weld between the second new furnace shell 2 and the sixth new furnace shell 6, then weld the vertical weld between the sixth new furnace shell 6 and the third new furnace shell 3, and then weld the upper and lower girth welds of the sixth new furnace shell 6, and the whole belt replacement of the blast furnace shell is completed.

[0034] Furthermore, the number of parts into which the whole furnace shell is split in step S1 is an even number, and an even number results in symmetrical welding, which offsets welding stress and strain.

[0035] Furthermore, the entire furnace shell in step S1 is split symmetrically according to the original welds of the furnace shell.

[0036] Furthermore, the vertical weld and the girth weld are welded by first welding the inner groove weld of the entire furnace shell and then welding the outer groove weld.

[0037] like Figure 2-Figure 3 As shown, the circumferential weld and the vertical weld are welded by segmented back-welding. The vertical weld is divided into two segments of back-welding, the first segment of back-welding 7 and the second segment of back-welding 8 are back-welded from the middle to both sides, and the circumferential weld is divided into six segments of back-welding, starting from the middle and symmetrically back-welding to both sides, and the order of segmented back-welding is first segment of back-welding 7-second segment of back-welding 8-third segment of back-welding 9.

[0038] Furthermore, after welding one layer of the vertical weld and the girth weld, the weld area is tapped with a stress relief instrument to release stress.

[0039] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical solutions and concepts of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for replacing the entire belt of a blast furnace shell without using temporary measures, characterized in that: The method for replacing the entire belt of a blast furnace shell comprises the following steps: S1. Split the entire furnace shell into several parts along the circumference and radial direction, confirm the splitting cutting line on the furnace shell, and mark the reference line; S2. Replace the furnace shell in a symmetrical manner, and use gas cutting to remove the most severely damaged area as the first piece of the old furnace shell to be replaced; S3. Replace the old furnace shell with a new furnace shell according to its structural form. After the new furnace shell is in place, weld the upper and lower circumferential welds of the first new furnace shell to be replaced; S4, determining the furnace shell at the diameter symmetrical position of the first old furnace shell as the second old furnace shell, removing the second old furnace shell by the same cutting method, and repeating the method of step S3 to weld the upper and lower girth welds of the replaced second new furnace shell; S5, repeat the replacement methods of S2 to S4 in the order of symmetrical replacement, replace the third old furnace shell on the adjacent side of the first old furnace shell and the fourth old furnace shell at the symmetrical position of the third old furnace shell, after the third new furnace shell and the fourth new furnace shell are in place, first weld the vertical weld between the two adjacent new furnace shells that have been replaced, and then weld the upper and lower girth welds of the new furnace shell; S6, repeat the replacement method of S5, replace the fifth old furnace shell adjacent to the other side of the first old furnace shell and the sixth old furnace shell symmetrically located to the fifth old furnace shell, after the fifth new furnace shell and the sixth new furnace shell are in place, first weld the vertical weld between the two adjacent new furnace shells, and then weld the upper and lower girth welds of the new furnace shell; S7, repeat the replacement method of S5 to S6, and replace the old furnace shells at the adjacent two side positions and the two side symmetrical positions in turn, until all the old furnace shells that have been split into a whole strip of furnace shells are replaced with new furnace shells, and the replacement of the whole strip of blast furnace shells is completed.

2. A method for replacing the entire belt of a blast furnace shell without using temporary measures according to claim 1, characterized in that: The number of parts into which the whole furnace shell is divided in step S1 is an even number.

3. A method for replacing the entire belt of a blast furnace shell without using temporary measures according to claim 1, characterized in that: In step S1, the entire furnace shell is split symmetrically according to the original welds of the furnace shell.

4. A method for replacing the entire belt of a blast furnace shell without using temporary measures according to claim 1, characterized in that: The vertical weld and the girth weld are welded by first welding the inner groove weld of the whole furnace shell and then welding the outer groove weld.

5. A method for replacing the entire belt of a blast furnace shell without using temporary measures according to claim 1, characterized in that: The girth weld and the vertical weld are welded by segmented back-welding.

6. A method for replacing the entire belt of a blast furnace shell without using temporary measures according to claim 1, characterized in that: After welding one layer of the vertical weld and the girth weld, the weld area is tapped with a stress relief instrument.

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