SU821496A1 - Air-heater of blast furnage - Google Patents

Description

(54) BOZjqyXOHAGPEBATELE DOMAIN FURNACE

one

The invention relates to ferrous metallurgy, in particular, to the design of an air heater for a blast furnace with a remote combustion chamber, and can be applied in all parts of the national economy, where high-temperature heating of gases is required.

The most (close to the technical essence and the achieved result of the invention is a blast furnace stove containing a nozzle and a combustion chamber freely suspended from a common dome connecting the chamber.

The occurrence of additional stresses due to temperature movements is eliminated. The combustion chamber / freely attached to the dome does not prevent the growth of the nozzle chamber.

However, the lack of fixing of the combustion chamber and the horizontal plane has the value of ni chambers of great length under long-flame burners; raest also occurs. The location of the joints to the combustion chamber of the hot air duct and the gas pipeline to the gas burner. The cyclic temperature change in the air duct, by hot blowing, causes its temperature displacements, which are transmitted to the combustion chamber, moving it in a horizontal plane. The constant movement of the chamber leads to cracking of the lining in its interface with the air duct, overheating of the metal and the appearance of cracks in it, which requires an immediate stop for repairs.

Similar phenomena occur in the place of interface between the combustion chamber and the gas pipeline to the gas burner. At the same time, the installation of a compensator on the air duct of the hot 5 blow does not exclude its effect on the combustion chamber. This is because the free-hanging chamber is not a fixed support for the air heater of the mountain to blow, but due to its deformability in the horizontal plane is shifted under the influence of the compensator stresses of the compensator. Moving the lower end of the horn chamber, in turn, causes significant effort and in the place of intersection with the dome. Constant alternating cyclic forces lead to the formation of cracks in this node, which in a critical situation can lead to a break in the combustion chamber. In addition to these effects, the combustion chamber senses the pressure of the wind, which causes its buildup in different directions. This contributes to the destruction of the junction of the combustion chamber with the dome, as well as the joints of gas and air ducts.

Thus / these disadvantages significantly reduce the resistance of the air heater.

The purpose of the invention is to increase the resistance of the air heater while increasing the temperature of the blow.

The goal is achieved by the fact that in the air heater, the combustion chamber of which is suspended through a box (about an annular beam) to a dome rigidly connected to the nozzle chamber, an additional annular beam is fixed in the lower part of the combustion chamber, rigidly fixed on the nozzle chamber and surrounding the combustion chamber with a gap, in which spring-loaded limiters for its horizontal displacement are placed at an angle of 120.

Thus, the combustion chamber, transferring the vertical load to the upper annular dome beam and freely moving in the vertical direction, is supported in the horizontal plane, which prevents horizontal displacements of the chamber. In this case, the structure becomes statically determinable and there is no force from thermal deformations.

The horizontal forces from the combustion chamber, caused by the movements of the hot air duct, are perceived by an additional (lower ring beam).

FIG. 1 shows the heater, a general view; FIG. 2, horizontal section of the air heater in the area of the lower annular beam (section AA in FIG. 1)

The heater contains the chambers of the nozzle 1 and 2 of the combustion, united by a common dome 3 located on the dome 4, in the lower part of the chamber 1 of the nozzle and 2 burning an additional (lower) annular beam 5 is installed, rigidly fixed to the casing of the chamber 1 of the nozzle by welding 6 and with respect to the chamber 2, the mount, or with a gap 7 (FIG. 2), in which, under the angle 120 °, limiters 8 are mounted for displacing the combustion chamber 2, Limiters 8 are fixed in the body of the additional annular beam 5.

The heater works as follows.

The combustion chamber 2 suspended from the dome 4 transfers to it the entire vertical load from the weight of refractories, metal structures and equipment. Horizontal effects from the combustion chamber 2 are transmitted through an additional annular beam 5 to the attachment chamber 1 mounted on the foundation. During the heating period, irregular thermal elongations of the combustion chambers 2 and 1 nozzles cause them to shift relative to each other. The free suspension of the combustion chamber 2 does not prevent its movement in the vertical direction, which completely eliminates the appearance of additional stresses and thereby increases the reliability of the design. The unrestricted movement of the combustion chamber 2 inside the annular beam 5 enclosing it is provided with spring-loaded stops. The radius of coverage of the spring-loaded stops is automatically changed depending on the radial thermal expansion of the casing of the combustion chamber 2 in the horizontal plane.

When switching to any heating mode, the operation scheme does not change, since the combustion chamber has complete freedom of movement along the vertical. Also, daily or seasonal changes in outdoor temperature can have no effect on the nature of the work.

The proposed technical solution allows to increase the reliability of the air heater and increase the durability of the casing and refractory lining, to simplify the design of the air heater. Improving the durability of the stove allows to increase the heating efficiency to blow without the device of special compensators. .

Claims (1)

Invention Formula A blast furnace air heater containing an external combustion chamber, a nozzle chamber, a refractory lining, a common dome above the chambers, mounted on an annular box girder, characterized in that, in order to increase the resistance of the air heater, an additional annular beam fixed on the bottom of the combustion chamber the nozzle chamber and the surrounding combustion chamber with a gap, in which spring-loaded stops are angled. Sources of information taken into account in the examination 1, RZh Metallurgi, 4, 5 4 V 168 (prototype).