Combined sealing cap for cooling wall of blast furnace

Abstract

The utility model discloses a combined sealing cap for a cooling wall of a blast furnace. The combined sealing cap comprises a semi-arc-shaped upper section and a semi-arc-shaped lower section, the upper valve outer diameter is smaller than the lower valve outer diameter and larger than or equal to the lower valve inner diameter, and the lower valve length is equal to or larger than the upper valve length; the two sides of the bottom of the upper section make contact with the two sides of the top of the lower section, the contact positions are connected through fillet welds, one ends of the upper section and the lower section are flush and connected to the furnace shell in a fillet welding mode, and the other ends are provided with closing-in plates. And the closing-in plates of the two closing-in plates form a pipe orifice matched with the cooling wall outer end water pipe sleeve on the radial surface and are connected to the cooling wall outer end water pipe sleeve in an angle welding manner. According to the structure, two butt welding seams of the two sealing caps are converted into fillet welding seams, the limitation of narrow operation space is solved, welding is convenient, and the welding quality can be improved.

Description

Technical Field

[0001] The utility model relates to a blast furnace cooling wall, in particular to a blast furnace cooling wall combined sealing cap. Background Art

[0002] The cooling stave is an important cooling device for the blast furnace body. It is installed on the inner side of the furnace shell. When working, cooling water enters the cooling stave through the inlet and outlet water pipes and then flows out, taking away the heat on the cooling stave body. The inner ends of the inlet and outlet water pipes are connected to the cooling stave body, and the inlet and outlet water pipes are connected to the peripheral water pipes after passing through the holes in the furnace shell. The inlet and outlet water pipes pass through the gaps at the holes in the furnace shell and are sealed with sealing caps at the places where they are exposed to the furnace shell. The sealing caps are used to prevent the high-temperature coal gas in the furnace from flowing out to the external space. The sealing caps are generally cylindrical, with one end welded to the outer wall of the furnace shell and the other end welded to the sleeve of the water pipe at the outer end of the cooling stave.

[0003] As the service life of the cooling wall increases, it will be affected by various factors and will experience deformation, thermal expansion, creep and other displacements. The water pipes on the cooling wall will also move with the displacement of the cooling wall, which will affect the sealing cap and cause it to deform or crack when it exceeds its stress limit. In addition, in the later period of the furnace service, due to increased rust and corrosion, the welds of the sealing cap will crack more frequently. Once the sealing cap cracks, the gas in the furnace will leak out, posing a great threat to safe production. The blast furnace needs to be shut down and production interrupted to deal with it.

[0004] The traditional sealing cap is an integrated structure. When deformation, damage, or gas leakage occurs, the sealing cap needs to be removed and replaced online. However, since the inlet and outlet water pipes need to be constantly flowing with water, the integrated sealing cap cannot be directly installed and welded.

[0005] In view of the above problems, the current solution is to cut the one-piece sealing cap into two halves, and use the wind down time to weld the two halves of the sealing cap online to their original position; this welding method has four welds to be welded, namely the annular fillet weld where the sealing cap connects to the furnace shell, the two butt welds on the bisecting line of the sealing cap, and the annular fillet weld between the sealing cap and the casing.

[0006] However, there are two problems with welding the two-piece sealing cap assembly: first, due to the obstruction of the adjacent water pipes and sealing caps, the working space is very narrow, and the welding quality of the two cross-section welds is difficult to guarantee; second, due to the limitation of the working space, the welding operation time is long, and the welding quality is prone to defects. During production, the welds are prone to cracking and deformation, which may cause gas leakage accidents again, and the air outage treatment is required, which increases the number of production interruptions. The long operation time also causes the air outage time to be extended. Utility Model Content

[0007] The utility model aims to provide a combined sealing cap for a blast furnace cooling wall. The structure transforms two butt welds of two-flap sealing caps into fillet welds, thereby solving the limitation of narrow working space, facilitating welding and improving welding quality.

[0008] The technical solution adopted by the utility model is:

[0009] A combined sealing cap for a blast furnace cooling wall comprises a semicircular upper flap and a lower flap; the outer diameter of the upper flap is smaller than the outer diameter of the lower flap and greater than or equal to the inner diameter of the lower flap, and the length of the lower flap is equal to or greater than the length of the upper flap; the bottom two sides of the upper flap are in contact with the top two sides of the lower flap and the contact points are connected by fillet welds, one end of the upper flap and the lower flap are flush and connected to the furnace shell by fillet welding, and the other end is provided with a closing plate, the closing plates of the two form a pipe opening on the radial surface that matches the water pipe sleeve at the outer end of the cooling wall and are connected to the water pipe sleeve at the outer end of the cooling wall by fillet welding.

[0010] Furthermore, arc transitions are used at the connections between the closing plate and the upper and lower petals.

[0011] Furthermore, the connection between the closing plate and the upper and lower lobes is directly at a right angle without transition.

[0012] Furthermore, the closing plates are respectively welded and fixed on the upper petal and the lower petal.

[0013] The beneficial effects of the utility model are:

[0014] This structure transforms the two butt welds of the two-petal sealing cap into fillet welds, solving the limitation of narrow working space (no need to weld flat next to the sealing cap, welding can be done on the upper side of the sealing cap facing downward), which not only facilitates welding, but also improves welding quality, and reduces the time and number of production interruptions caused by online processing of gas leakage from the sealing cap. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a front view of the combined sealing cap of the blast furnace cooling wall in the first embodiment of the utility model.

[0016] Figure 2 It is a side view of the combined sealing cap of the blast furnace cooling wall in the first embodiment of the utility model.

[0017] Figure 3 It is a front view of the combined sealing cap of the blast furnace cooling wall in the second embodiment of the utility model.

[0018] Figure 4 It is a side view of the combined sealing cap of the blast furnace cooling wall in the second embodiment of the utility model.

[0019] In the figure: 1-upper petal; 2-lower petal; 3-closing plate; 4-pipe opening. DETAILED DESCRIPTION

[0020] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0021] Embodiment 1

[0022] This embodiment discloses a combined sealing cap for a blast furnace cooling stave, such as Figure 1 and Figure 2 As shown, it includes a semicircular upper flap 1 and a lower flap 2; the outer diameter of the upper flap 1 is smaller than the outer diameter of the lower flap 2 and is greater than or equal to the inner diameter of the lower flap 2, and the length of the lower flap 2 is equal to or greater than the length of the upper flap 1; the bottom sides of the upper flap 1 are in contact with the top sides of the lower flap 2 and the contact points are connected by fillet welds, one end of the upper flap 1 and the lower flap 2 are flush and connected to the furnace shell by fillet welding, and the other end is provided with a closing plate 3, and the closing plates 3 of the two form a pipe mouth 4 on the radial surface that matches the water pipe sleeve at the outer end of the cooling wall and are connected to the water pipe sleeve at the outer end of the cooling wall by fillet welding. In this embodiment, as Figure 2 As shown, arc transition is adopted at the connection between the closing plate 3 and the upper petal 1 and the lower petal 2. In this embodiment, the closing plate 3 is welded and fixed on the upper petal 1 and the lower petal 2 respectively.

[0023] When the sealing cap needs to be replaced: 1) When the blast furnace is shut down, clean the old sealing cap, wrap the upper and lower petals 1 and 2 of the new sealing cap with the closing plate 3 to wrap the water pipe casing at the outer end of the cooling wall and spot weld them; 2) Weld the contact points of the upper and lower petals 1 and 2 with the furnace shell; 3) After checking that the positions of the welds are correct, use fillet welds to fully weld the contact ends of the upper and lower petals 1 and 2 with the furnace shell; 4) Use fillet welds to fully weld the bottom sides of the upper petal 1 and the top sides of the lower petal 2; 4) Use fillet welds to fully weld the closing plates 3 of the upper and lower petals 1 and 2 with the water pipe casing at the outer end of the cooling wall.

[0024] This structure transforms the two butt welds of the two-petal sealing cap into fillet welds, solving the limitation of narrow working space (no need to weld flat next to the sealing cap, welding can be done on the upper side of the sealing cap facing downward), which not only facilitates welding, but also improves welding quality, and reduces the time and number of production interruptions caused by online processing of gas leakage from the sealing cap.

[0025] Embodiment 2

[0026] This embodiment discloses a combined sealing cap for a blast furnace cooling stave, such as Figure 3 and Figure 4 As shown, its structure is similar to that of the first embodiment, except that the connection between the closing plate 3 and the upper petal 1 and the lower petal 2 is directly connected at right angles without transition. In this embodiment, the closing plate 3 is welded and fixed to the upper petal 1 and the lower petal 2 respectively.

[0027] Application Examples

[0028] A 2800m3 blast furnace, a casing of a furnace shell is leaking gas and needs to be replaced. The size of the on-site sealing cap is φ168×5mm, the length is 180mm, and the size of the outer end water pipe casing is φ89 (outer diameter φ95). The new sealing cap is prepared as follows: upper petal 1 - size φ160×5mm, radial length 180mm, one end reserved φ95 notch closing plate 3; lower petal 2 - size φ170×5mm, radial length 185mm, end reserved φ95 notch closing plate 3.

[0029] The embodiments described above are part of the embodiments of the present application, rather than all of the embodiments. The detailed description of the embodiments of the present application is not intended to limit the scope of the present application for protection, but merely represents the selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

Claims

1. A combined sealing cap for a blast furnace cooling stave, characterized in that: It comprises a semicircular upper lobe and a lower lobe; the outer diameter of the upper lobe is smaller than the outer diameter of the lower lobe and is greater than or equal to the inner diameter of the lower lobe, and the length of the lower lobe is equal to or greater than the length of the upper lobe; the bottom sides of the upper lobe are in contact with the top sides of the lower lobe and the contact points are connected by fillet welds, one end of the upper lobe and the lower lobe are flush and connected to the furnace shell by fillet welding, and the other end is provided with a closing plate, and the closing plates of the two form a pipe mouth matching the water pipe sleeve at the outer end of the cooling wall on the radial surface and are connected to the water pipe sleeve at the outer end of the cooling wall by fillet welding.

2. The combined sealing cap for a blast furnace cooling stave according to claim 1, characterized in that: Arc transition is adopted at the connection between the closing plate and the upper petal and the lower petal respectively.

3. The combined sealing cap for a blast furnace cooling stave according to claim 1, characterized in that: The connection between the closing plate and the upper and lower petals is directly at right angles without transition.

4. The combined sealing cap for blast furnace cooling stave according to any one of claims 1 to 3, characterized in that: The closing plates are respectively welded and fixed on the upper petal and the lower petal.

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