RU2235134C1 - Plate type cooler for metallurgical furnaces - Google Patents

Abstract

FIELD: metallurgy, namely processes and apparatuses for cooling shafts of metallurgical furnaces, possibly systems for water and evaporation type cooling of jackets of blast furnace shafts and cupolas.

SUBSTANCE: plate type cooler for metallurgical furnaces includes plate with ribs on working surface and cast-in to plate cooling tubes. Ribs are intermittent ones; they have grooves with depth consisting 0.1 - 1.0 of rib height and length consisting 0.1 - 1.5 of thickness of rib base.

EFFECT: enhanced operational strength of plate type cooler.

10 cl, 2 dwg, 1 ex

Description

The invention relates to metallurgy, in particular to methods and devices for cooling mines of metallurgical furnaces, and can be used in systems for water and evaporative cooling of casings of mines of blast furnaces and cupolas.

Known cast iron stove fridge for a blast furnace, containing a cast iron plate, which may have horizontal fins on the working surface and cooling coils filled in a cast iron plate made of high-strength cast iron with spherical graphite (RF Patent No. 2151195, IPC 7 C 21 V 7/10, publ. 2000, Bull. No. 17). Such a refrigerator has a low resistance, because the ribs on the working surface of the plate are solid, which leads to the rapid formation of cracks on them and the premature exit of the refrigerator from operation.

Known plate refrigerator of a metallurgical furnace, the working surface of which is divided by ribs into cells of a hexagonal or oval shape (SU No. 1092177, IPC 3 C 21 V 7/10, publ. 1984). The disadvantage of this design of the outer surface is the low resistance of the refrigerator, because the ribs between the cells are solid; as a result, thermal fatigue cracks form in them, leading to breakdown of the refrigerator.

Known stove refrigerator blast furnace, consisting of a cast iron plate filled with cooling pipes, and the outer lining is made in the form of adjacent plates made of wear-resistant cast iron, mounted in the body of the plate as a “dovetail”, while between the plates and the body of the stove a layer of refractory paint was applied (AS USSR No. 545676, IPC 2 C 21 V 7/10, publ. 1977). The disadvantage of this refrigerator is its low durability, because plates isolated from the body of the refrigerator quickly overheat and wear out or fall out of the grooves, which are also prone to cracking.

Closest to the claimed is a plate refrigerator containing a plate with solid ribs on the working surface (AS USSR No. 222413, IPC 2 C 21 V 7/10, publ. 1978).

The disadvantage of the prototype is the low operational stability of the refrigerator when used in a blast furnace due to the rapid formation of cracks due to low-cycle fatigue in solid fins, leading to the destruction of the refrigerator plate.

EFFECT: increased operational stability of a plate refrigerator for metallurgical furnaces.

The technical result is achieved in that in a plate refrigerator for metallurgical furnaces containing a plate with fins on the working surface and cooling pipes poured into the plate, the fins are intermittent with a groove depth of 0.1-1.0 of the height of the rib and a groove length of 0, 1-1.5 of the thickness of the base of the ribs. The height of each rib is 0.10-0.95 of the thickness of the plate. The ribs are associated with the surface of the plate with a radius of 5-35 mm, and the distance between the rows of ribs is 0.1-1.9 of the thickness of the base of the ribs. The side walls of the ribs are inclined relative to the surface of the plate at an angle of 15-160 °. The grooves in each rib are located one above the other in height of the refrigerator. The stove and fins of the stove refrigerator can be made of ductile iron with spherical or vermicular graphite, as well as copper and / or its alloys or steel.

The fins in the stove refrigerators are used to hold the refractory mass, which fills the space between the fins, and they provide a more developed working surface, which allows for increased heat removal from the furnace casing. However, in the prototype plate, the ribs are made in continuous rows. During operation of the refrigerator, the fins will undergo periodic heating to high temperatures (600-900 ° C) and cooling, which leads to the rapid formation of thermal fatigue cracks in them. With further operation of the refrigerator, cracks propagate into the body of the plate, which leads to its breakdown. As a result, the refrigerator prematurely fails, often not having worked out the time prescribed for it.

In the claimed design of the plate refrigerator, the fins are intermittent, which provides each section of the fins with the possibility of free expansion and contraction during heating and cooling of the refrigerator. As a result, thermal fatigue cracks do not form in such ribs, which prevents plate destruction, since stresses arising in such a plate are below the conditional yield strength. It was found that the depth of each groove in the rib should be equal to 0.1-1.0 of the height of the ribs. With a smaller groove depth, cracks in the remains of the ribs are still possible, and with a larger value, the thickness of the plate decreases, which reduces its resistance. The length of each groove should be 0.1-1.5 of the thickness of the base of the rib, otherwise, cracks occur in the rib with a smaller groove length, and cracks do not form with a larger groove length, but the total length of the ribs decreases sharply, which reduces durability of the refrigerator.

To reduce the concentration of stresses and reduce the likelihood of ribs breaking off, they are conjugated to the surface of the plate with a radius of 5-35 mm, and the distance between the rows of ribs is 0.1-1.9 of the thickness of the base of the ribs. The height of the ribs is 0.10-0.95 of the thickness of the plate. With a smaller height of the ribs, the heat removal from the refrigerator is reduced, and with a larger height, the ribs are separated from the stove. The side walls of the ribs are inclined relative to the surface of the plate at an angle of 15-160 °. When the angle of inclination is smaller than the lower limit, the edges of the ribs become thin and thermal fatigue cracks quickly form in them due to overheating. When the angle of inclination is greater than the upper value, the side walls of the ribs become flat, as a result, the protective refractory mass and the skull quickly leave the surface of the plate, which leads to its rapid failure. The grooves in the ribs are located along the height of the refrigerator under each other. To increase the service life of the stove refrigerator, the stove and fins are made of ductile iron with spherical or vermicular graphite, copper and / or its alloys, or steel.

The invention is illustrated by drawings, where in Fig.1 shows the design of a plate refrigerator with intermittent ribs on the working surface, in Fig.2 - options for tilting the side wall of the ribs with an acute and obtuse angle.

In the figures, the numbers and letters indicate:

1 - plate;

2 - cooling pipes;

3 - horizontal ribs;

4 - grooves in the rib;

H is the thickness of the plate;

h is the height of the ribs;

a - groove depth;

in - the thickness of the base of the ribs;

C is the length of the groove;

d is the distance between the rows of ribs;

R is the radius of pairing of the ribs with the surface of the plate;

α is the angle of inclination of the side wall of the rib relative to the surface of the plate.

The claimed plate refrigerator for metallurgical furnaces contains a plate 1 of thickness H, into which cooling tubes 2 are poured. On the working side of the plate there are horizontal ribs 3 of height h and base thickness b. The ribs are made intermittent with grooves 4 of depth a and length c. The ribs are associated with the surface of the plate with a radius R. The distance between the horizontal rows of ribs is d. The angle of inclination of the side wall of the rib relative to the surface of the plate is equal to α.

An example of a stove refrigerator. A plate refrigerator for metallurgical furnaces contains a plate and fins made of ductile iron with spherical graphite, into which cooling steel pipes are filled. On the working surface of the refrigerator there are horizontal discontinuous ribs with a rib height h = 60 mm and a base thickness of = 75 mm. The depth of the grooves in the ribs is equal to the height of the rib and is a = h = 60 mm, and the length of each groove is c = 40 mm. The grooves in each rib along the height of the refrigerator are located under each other. The ribs are associated with the surface of the plate with a radius of R = 12 mm. The distance between the horizontal rows of ribs is equal to the thickness of the base of the ribs and is d = B = 75 mm. The thickness of the plate is H = 170 mm. The angle of inclination of the side wall of the ribs relative to the surface of the plate is α = 90 °.

The technical and economic advantage of the claimed design of a plate refrigerator is to increase its resistance by preventing the formation of thermal fatigue cracks in the ribs and premature destruction of the refrigerator. As a result, the stability of the blast furnace is increased, the period of its operation between overhauls is increased, and the conditions for melting are facilitated.

Claims (10)

1. Plate refrigerator for metallurgical furnaces, containing a plate with fins on the working surface and cooling pipes poured into the plate, characterized in that the fins are intermittent with a groove depth of 0.1 ÷ 1.0 from the height of the rib and a groove length equal to 0.1 ÷ 1.5 of the thickness of the base of the ribs. 2. Plate refrigerator according to claim 1, characterized in that the height of the ribs is 0.10 ÷ 0.95 of the thickness of the plate. 3. A plate refrigerator according to any one of claims 1 and 2, characterized in that the distance between the rows of ribs is 0.1 ÷ 1.9 of the thickness of the base of the ribs. 4. Plate refrigerator according to any one of claims 1 to 3, characterized in that the ribs are mated to the surface of the plate with a radius of 5 ÷ 35 mm. 5. A plate refrigerator according to any one of claims 1 to 4, characterized in that the side walls of the ribs are inclined relative to the surface of the plate at an angle of 15 ÷ 160 °. 6. Plate refrigerator according to any one of claims 1 to 5, characterized in that the grooves in each rib are located one above the other along the height of the refrigerator. 7. A plate refrigerator according to any one of claims 1 to 6, characterized in that the plate and fins are made of ductile iron with spherical graphite. 8. A plate refrigerator according to any one of claims 1 to 6, characterized in that the plate and fins are made of ductile iron with vermicular graphite. 9. A plate refrigerator according to any one of claims 1 to 6, characterized in that the plate and fins are made of copper and / or its alloys. 10. A plate refrigerator according to any one of claims 1 to 6, characterized in that the plate and fins are made of steel.

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