JPH01306513A - Cooling panel for shaft furnace - Google Patents

Abstract

PURPOSE: To provide a cooling panel for blast furnace capable of substantially increasing the service life by tightly connecting a thick layer made of refractory concrete to a main surface of a cast iron plate in which a cooling pipe is embedded through a casting profile structure.

CONSTITUTION: A cooling pipe 14 open in one main surface is embedded in a cast iron plate 12 to form a cooling panel 10 for blast furnace. In the cooling panel 10, a thick layer 16 made of refractory concrete is installed on the other main surface of the cast iron plate 12 before installation so as to be tightly connected to this surface. In order to improve adhesion of the layer 16 to the plate 12, a casting profile structure comprising a groove 18, etc., extending in the horizontal direction is arranged on the other main surface of the cast iron plate 12. The structure can comprise a cusp, etc., in addition to the groove 18, etc., of rectangular or circular section. The service life of the cooling panel can be increased, and the frequency of repairing works of a blast furnace wall can be reduced thereby.

COPYRIGHT: (C)1989,JPO

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cooling panel for a blast furnace in which cooling pipes opening in one of the main surfaces of a cast iron plate are embedded in the plate.

Two main types of cooling systems for blast furnaces are currently known. That is, a cooling box system and a system with a cooling plate, also now referred to as a "5tave cooler."

The cooling plate consists of cast iron panels made by casting. Cooling tubes or coils pass through these plates on the inside and also parallel to the main plane. Such a board is, for example, document DE-C2-2,90
3,104.

These tubes are generally bolted to the inside surface of the jacket, completely lining it. Its advantage over the cooling box is that it forms a thermal screen behind the jacket, ensuring more uniform cooling, thereby compensating for sudden local increases in temperature, but this is different from the local isolated cooling of the cooling box. to be contrasted, and even allows cooling by evaporation.

Considering the thermal conditions, conventionally using only a cooling plate is
It is necessary to relate refractory bricks to this, knowing that the compatibility between refractory bricks and cast iron is poor. Therefore, a thick brickwork of refractory bricks is usually formed inside the furnace after the installation of the plates. However, this brick structure is subject to significant wear due to mechanical, thermal and chemical causes. Furthermore, since the compatibility between cast iron and refractory bricks, especially in a thermal sense, is poor, due to vertical thermal expansion,
Firebrick masonry separates from cooling plate. Entire sections of refractory brickwork will collapse, tearing off or carrying away adjacent sections of brickwork during the fall.

When the brickwork disappears, a deposit called a ``lining'' re-forms on the inner surface of the cold plate, then disappears and forms again, periodically repeating the process; It's still easy to get hurt.

Attempts have been made to remedy these shortcomings by providing the boards with lugs that project from the inside surface of the board to more firmly bond the brickwork together. However, these lugs prove to be one of the weakest parts of the board.

Attempts have also been made to place refractory bricks on the inner surface of the plate in order to reduce the thermal stresses created in the cold plate and to assist in the formation and adhesion of a "lining" on the inner surface of the plate after the refractory brickwork has dissipated. ing.

None of these improvement measures achieved the desired results;
It has been impossible to extend the life of blast furnace walls and reduce the frequency of repair work.

It is an object of the invention to provide a new cooling panel making it possible to substantially extend the service life of the cooling panel.

To achieve this objective, the invention provides a panel of the type mentioned at the outset, which is characterized in that the other major side of the board is covered with a thick layer of refractory concrete before its installation. The other side of the cast iron plate is provided with a cast profile structure to provide a tight connection to the surface and to improve the adhesion of the layer to the plate.

An advantage of the present invention is that it radically departs from the preconceptions required for refractory brickwork and designs a composite cooling panel that retains fire protection but no longer requires brickwork inside the furnace. Unlike the prior art, where there are always two separate elements, the cast iron plate and the refractory masonry, which are not well compatible with each other, the present invention provides a single composite element, which can be of different types. However, it tightly connects two materials with complementary properties to each other.

In conventional cooling installations, the refractory brickwork is more or less self-supporting. That is, each brick must support all the bricks located on its L side. However, the panels according to the invention, in particular the layer of refractory concrete, are completely independent of the phase. That is, if the refractory concrete collapses locally, this will not adversely affect adjacent panels.

Since the panels are independent of each other, different thermal expansions do not significantly affect the connection between the refractory concrete and cast iron. By providing an expansion gap concrete layer oriented in a suitable manner by the direction of thermal and mechanical stresses, this problem can be virtually completely eliminated.

Another important advantage of the panels according to the invention is that they can be manufactured entirely in the factory and bolted to the furnace jacket in a single operation, whereas traditionally blast furnace repair involves two successive operations. It will be done.

That is, first install the boards and then add the refractory brickwork. Needless to say, the reduction in furnace downtime for the construction of furnace walls is of considerable economic benefit.

Historically, the preforming of panels, especially the laying of refractory concrete onto cast iron plates for bag-to-bag purposes, has been associated with the construction of fireproof walls and the lining of cast iron plates in the furnace. It can be carried out under the best conditions favorable for good adhesion of concrete.

Furthermore, it is preferred that the internal profile structure improves the adhesion between the concrete layer and the cast iron plate. This structure can consist of grooves, waves or fins of rectangular cross section which extend horizontally in the panel after installation. It can also be an isolated cusp of oval or round cross section.
It can also consist of

Other features will become apparent from the following description of advantageous embodiments with reference to the accompanying drawings.

FIGS. 1 to 4 are neutral cross-sectional perspective views, with cooling pipes and concrete layers partially cut out to show the profile of the inner surface of the cast iron plate.

FIG. 1 shows a cooling panel of the present invention, which consists of a cast iron plate 12
In this cast iron plate, pipes 14 for circulating cooling fluid are embedded in a well-known manner.

The inner surface of this plate 12 has horizontal grooves 18 of square or rectangular cross section comparable to the grooves present in known cooling plates.

The refractory concrete forming layer 16 contains cement.
1) It is high-density concrete with low. Its basic component is silicon carbide. Density is 2.5 or more, thermal conductivity is 5
Tested on concrete with w/m k or higher. A
It was CO low resistance class 8 according to STMc288.

In the test of resistance to alkali, K at 1000°C
, CO, vapors for 200 hours, no damage was observed. A Jourdan abrasion test was conducted, and the loss after 500 revolutions was less than 2%. The panel 20 of the embodiment shown in FIG. 2 is similar to the panel 10 shown in FIG. The inner groove 28 has a round cross-section and takes the form of a horizontal wave as a whole. Rounding the grooves helps prevent early failure in cast iron and concrete, which typically occurs at sharp edges and is caused by temperature gradients in the cast iron and concrete and thermal expansion of the concrete and cast iron. 7: Internal stress caused by differences.

In the embodiment of panel 30 of FIG. 3, the profile of panel 20 of FIG. It extends to The connection between the concrete layer and the plate 32 is therefore of the dovetail type with rounded corners, i.e. the plate 32
grooves defined between fins 38 that widen toward the inner surface of the fins.

This profile design of the inner surface of the plate 32 serves to provide a good bond of the refractory concrete to the plate 32.

The cooling panel 40 of the FIG. 4 embodiment has an inner surface profile of the plate 42 consisting of isolated cusps 48 arranged in a staggered manner and having substantially the cross-section of the fins 38 of the FIG. 3 embodiment. The advantage of this design over the embodiment of FIG. 3 is that the profile of plate 42 is less likely to crack vertically as a result of normal stresses. The risk of cracking is greatest in the area of cooling pipes. That is, it is greatest where the temperature gradient is greatest.

The panel 50 of the embodiment of FIG. 5 is similar to the panel 40 of the embodiment of FIG. That is what we are doing. The staggered distribution of cusp 58 is shown in Figure 5a.

This profile is therefore more pronounced in the embodiment of FIG. The distribution of cusps 58 provides uniform and balanced cooling of the layer of refractory concrete 56, thereby reducing the risk of cracking.

[Brief explanation of the drawing]

1 is a perspective view of a first embodiment of a cooling panel according to the invention; FIG. 2 is a similar view of a second embodiment of a cooling panel; FIG. 3 is a similar view of a third embodiment of a cooling panel; FIG. 4 is a diagram of a fourth embodiment of the cooling panel, and FIG. 5 is a vertical sectional view of the fifth embodiment of the cooling panel. 12.42. ,,board, 14. ,, cooling pipe, 18.28
10, groove, 38. ,, Fin, 48.58
．． ,, Cusp.

Claims (1)

[Claims] 1. A cooling pipe (1
4) is embedded in the plate (12), a thick layer of fire-resistant concrete is laid on the other main surface of the plate (12) before its installation, tightly connected to this surface, and the plate (12) is
12) A panel characterized in that it is provided with a cast profile structure on said other side of the cast iron plate (12) in order to improve the adhesion of said layer (16) to said layer (16). 2. The panel of claim 1, wherein the structure comprises a groove extending horizontally in the panel after installation. 3. Panel according to claim 2, characterized in that the groove (18) has a rectangular cross section. 4. Panel according to claim 2, characterized in that the grooves (28) have a round cross-section in the form of waves. 5. Panel according to claim 2, characterized in that the grooves are defined between fins (38) of oval cross-section and take the form of dovetail grooves with rounded corners. 6. The panel of claim 2, wherein the structure is formed by isolated cusps arranged in a staggered manner on the inner surface of the plate. 7. Panel according to claim 6, characterized in that the cusp (48) has a flat oval cross-section attached to the plate (42) by narrow ribs. 8. Panel according to claim 6, characterized in that the cusp (58) is in the form of a sphere. 9. Panel according to any one of claims 1 to 8, characterized in that the concrete layer has an expansion gap.