RU2258742C1 - Method of reconditioning cooling system of blast furnace shaft - Google Patents

Abstract

FIELD: metallurgy; reconditioning cooling systems of blast furnace shafts.

SUBSTANCE: proposed method includes replacement of defective horizontal coolers in height of blast furnace shaft; new cooling elements of "double pipe" type are mounted between joints of vertical coolers through holes provided in furnace jacket instead of inoperative horizontal coolers; inner water supply pipe of "double pipe" cooler is connected to pressure part of operating cooling system and outer water discharge pipe is extended to peripheral near-wall area of furnace.

EFFECT: increased service life of lining; reduced periods of reconditioning; low cost.

1 dwg, 1 ex

Description

The invention relates to ferrous metallurgy, in particular to methods for the repair of a cooling system for a mine shaft of a blast furnace.

Known for the typical design of the walls of the furnace, including steel outer armor, on the inside of which there are plate refrigerators and a multi-layer lining made of aggregate and refractory bricks (Pharmacist S.S. et al. Organization of repair of equipment of metallurgical enterprises. - Kiev: Technique, 1981, p. 89-92). In another embodiment of the wall structure (RU No. 2175982, IPC С 21 В 7/10, 2001), it is proposed to additionally fill the gaps between armor, refrigerators, and refractories with metal fillers having high thermal conductivity.

None of these methods takes into account the need for less time-consuming accelerated repairs of the existing blast furnace shaft cooling system, does not exclude excessive cutting of armor, and does not enhance the protective characteristics of the lining of walls in contact with the movable charge in the wall areas of the furnace working space.

A disadvantage of the known methods is that significant wear of the refractory lining with deterioration of the integrity of the armor is accompanied by expensive repair measures that are not focused on the operational buildup of an additional protective layer of the skull on the inner surface of the walls to extend the overhaul period of their operation.

The closest to the claimed method in terms of technical nature and the achieved effect is a method for the repair of a cooling system of a mine’s blast furnace shaft (RU No. 2170768, IPC C 21 V 7/10, 2001), in which new horizontal cooling elements are mounted between the casing of the shaft of the blast furnace and formwork, and then the gaps and openings are filled with refractory mortar.

The disadvantage of this method is that it provides for the implementation of additional holes and cutting parts of the armor to establish new refrigerators, and therefore, reducing the operational reliability of the casing. On the other hand, as in other analogues, the prototype does not provide enhanced protective characteristics of the refractory masonry of the inner part of the walls of the furnace.

The technical result of the invention is to create such a method of repair repair of the cooling system, which will increase the service life of the refractory lining with reduced time and cost of repair.

The specified technical result is achieved by the fact that in the method for the repair of the cooling system of the mine’s blast furnace shaft, which includes replacing the failed horizontal refrigerators in the height of the cooled part of the blast furnace shaft, in the spaces between the vertical refrigerators through the openings in the furnace casing, in place of the muffled inoperative horizontal refrigerators new cooling elements of the “pipe in pipe” type, while the internal water supply pipe is connected to the pressure part and the existing cooling system, and the external drain pipe - the glass is advanced into the peripheral wall region of the furnace.

The usefulness of the proposed method is due to the fact that lowering the temperature of the part of the refractory wall adjacent to the drain pipe-glass in the furnace contributes to the formation of a stable additional skull, which is also more reliably held by the protrusion of the pipe into the furnace.

The repair method is as follows. New cooling elements are made at the beginning of the furnace shutdown for repair. The remains of the muffled refrigerators of the mine cooling system on the furnace stopped for repair are removed to the furnace to free up the installation site of new cooling elements. As shown in the diagram, new pipe-in-pipe cooling elements, consisting of an external blanked drain pipe 1 and an internal pipe 2, are installed between the vertical refrigerators 3. The pipe 2 and the pipe 1 with a fitting 4 are connected to the cooling system mine, and the cooling element itself, passing through the gasket 5 and the remnants of cast-iron putty 6, are connected hermetically to the casing of the mine 7.

The proposed cooling element in the composition of the water supply pipe 2, water discharge pipe 1 and nozzle 4 is a convenient design in which the replacement of the water discharge pipe 1 can be made as necessary to clean the water supply pipe 2 without violating the integrity of the casing 7 of the shaft and the lining of the furnace.

In addition to the convenience of design and ease of manufacture of the proposed cooling element, the implementation of the inventive repair method simplifies the technology of its assembly, installation and installation on the furnace. A simplified set of mechanical devices, equipment and low weight of cooling elements can significantly reduce installation time and reduce the cost of the repair work as a whole. Using the proposed design provides the possibility of accelerated heat removal from the front of the pipe-cup, and also leads to the formation of a stable skull and higher resistance of the inner part of the lining of the furnace.

An example of a practical implementation of the method. At the blast furnace No. 3 with a volume of 2000 m ^{3 of} OJSC Severstal, during the period of restoration repair of the furnace of the third category in several rows around the shaft of the furnace, new cooling elements were installed to replace the failed horizontal refrigerators. The water inlet and outlet pipes were connected to a common shaft cooling system, the height of each tube-tube in the furnace was 100 mm.

The repair cost was reduced by 2 times compared with the standard solution. The durability of the mine and all refrigerators of the cooling system has increased - for 9 months of operation, not a single new cooling element has failed. As a result of the application of the method, the mine’s working profile stabilized, and the following decreased: thermal loads on the furnace’s armor, vertical refrigerators, circumferential unevenness according to peripheral thermocouple readings, and specific coke consumption.

Claims (1)

A method of reconditioning a cooling system of a blast furnace shaft mine, which includes replacing failed horizontal refrigerators in height of the cooled part of the blast furnace shaft, characterized in that new cooling elements are installed in the gap between the vertical coolers through openings in the furnace casing in place of the muffled horizontal refrigerators "pipe in pipe", while the internal water supply pipe is connected to the pressure part of the existing cooling system, and in The external drain pipe-glass is extended into the peripheral wall region of the furnace.