JPH0633942B2 - Method for extracting heated material from rotary hearth type heating furnace - Google Patents

Description

The present invention relates to a method for extracting a material to be heated in a rotary hearth type heating furnace.

(Prior Art) Generally, in a rotary hearth type heating furnace, as shown in FIG. 3 (a), the hearth 6 is moved in the forward direction indicated by an arrow X (in the present invention, the material to be heated charged from a charging port is charged). Is heated in the furnace and advances toward the extraction port as the front side, and the opposite direction is referred to as the rear side) to move the heated material W ₁ to the position of the extraction port 4. As shown in (b) and (c), the extraction door 7
Open and extract the top heated material W ₁ by the extractor 8. After extraction, the extraction port door is closed and the hearth 6 is further separated by a distance P between the heated materials in the direction of arrow X as shown in FIG. Then, the material is extracted by repeating the above steps. 11
Is a baffle that separates the extraction port 4 side and the charging port (not shown) side, and is vertically fixed to the ceiling 14 of the furnace.

(Problems to be Solved by the Invention) However, in the above conventional method for extracting a material to be heated, FIG.
During the extraction operation of the heated material W ₁ shown in (c) and (d), the succeeding heated material is in the vicinity of the opened extraction port 4, so that cold air enters from outside the furnace and heat radiation to the outside of the furnace occurs. There is a problem in that the temperature of the material to be heated is lowered and the heat loss from the furnace is large. Further, as shown by a chain line in FIG. 3, it has been attempted to provide a baffle 21 similar to the baffle 11 at a position closer to the soaking zone 17 than the extraction port 4, but in this case as well, the succeeding target is the same as the above. The problem of cooling the heat material (especially the material W ₂ to be heated) is not solved.

The present invention solves the above-mentioned conventional problems, and an object of the present invention is to provide a method for extracting a heated material of a rotary hearth type heating furnace capable of suppressing a temperature decrease and a heat loss of a subsequent heated material during extraction of the heated material. It is a thing.

(Means for Solving the Problems) However, the method for extracting a material to be heated according to the present invention has a closed door position where the lower end of the door reaches the hearth and an opening for forming a vertical gap larger than the height of the material to be heated on the hearth. A partition door that is driven up and down between the door position is provided in the form of partitioning the inside of the furnace at a position near the soaking zone from the extraction port, and after the heat receiving material stands by behind the partition door,
The partition door is opened, the hearth is rotated in the forward direction to move the first heated material to the extraction port position, and the heated material is extracted by the extractor, and the heated material is extracted by the extractor. After lifting, the hearth is rotated in the backward direction to move the subsequent material to be heated to the position behind the partition door, the partition door is closed, and the above steps are repeated to sequentially extract the material to be heated. Is a method for extracting a material to be heated in a rotary hearth type heating furnace.

(Operation) In the method for extracting a material to be heated of the present invention, when the material to be heated is extracted from the extraction port, if the head material to be heated is lifted, the hearth is rotated in the backward direction and the subsequent material to be heated is extracted. Since the material is moved to the rear position of the partition door and the partition door is closed, the partition door blocks the extraction port portion and the soaking zone. As a result, during the extraction of the material to be heated by the extractor, both the time during which the material to be heated comes into contact with the cold air from the extraction port and the time during which heat is radiated from the heated material to the outside of the furnace through the extraction port This shortens the temperature of the material to be heated and suppresses heat loss from the furnace.

(Embodiment) An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

In the figure, 1 is a rotary hearth type heating furnace, 2 is its inner furnace wall, 3
Is an outer furnace wall, 4 is an extraction port provided in the outer furnace wall,
5 is also a booth. 6 is an outer furnace wall 3 and an inner furnace wall 2
An annular flat plate-shaped hearth provided between and is rotatably supported on an annular rail, and a predetermined amount in a forward direction indicated by an arrow X and a backward direction indicated by an arrow Y by a drive device (not shown). It is designed to be rotated. 7 is an extraction door, 8 is an extractor, 9 is a loading door, and 10 is a loading machine.
Reference numerals 11, 12 and 13 are baffles vertically fixed to the ceiling 14 of the furnace. The baffle 11 separates the charging port 5 and the extraction port 4 from each other, and the baffle 12 partitions the pretropical zone 15 and the heating zone 16 from each other. Reference numeral 13 is provided to separate the heating zone 16 and the soaking zone 17. On the other hand, reference numeral 18 is a partition door for partitioning the inside of the furnace in the traveling direction of the material to be heated, which is provided at a position closer to the soaking zone 17 than the extraction port 4. Both ends 18 of the partition door 18
The a is guided up and down by the outer furnace wall 3 and the inner furnace wall 2, and the penetrating portion of the ceiling 14 is sealed by a seal such as asbestos packing. The partition door 18 is opened and closed by being driven up and down by an electric winch type elevator drive device (not shown) similar to the elevator drive device of the loading door 7. Note that FIG. 2 is a sectional development view of the hearth width 6 of the hearth 6. Further, in FIG. 2, a large number of burners are provided on the inner furnace wall 2 and the outer furnace wall 3, but the illustration thereof is omitted.

In the apparatus having the above configuration, the material to be heated W (W ₁ , W ₂ , W ₃ ...
Extraction of (... generic name) is performed as follows. Entrance 5
The heated material W placed on the hearth 6 by the pitch P (value on the furnace width center line 19) and heated by passage of the pre-tropical zone 15, the heating zone 16, and the soaking zone 17 is shown in FIG. As shown in a), the standby position behind the partition door 18 in the closed state is reached. The partition door 18 is in a state where its lower end portion 18b is in contact with the hearth 6 or is separated from the hearth 6 by a small amount of clearance, that is, in the closed position. At the time of extraction, as shown in FIG.
The bottom of the hearth 6 is raised to a door opening position where a large vertical gap H is formed between the lower end 18b and the hearth 6 by a predetermined amount (for example, 20 to 30 mm) depending on the height of the heated material W, and then the hearth 6 is separated by a distance L.
Forward direction (arrow X direction) only (value on furnace width center line 19)
The _first heated material W ₁ is moved to the position of the extraction port 4. Next, as shown in FIG. 6C, the extraction door 7 is opened, and the heated material W ₁ is lifted by the extractor 8 as shown in FIG. Distance S in the direction
(= L-P) is only rotated to move the trailing of the heated material W ₂ to the standby position of the rear of the partition door 18 closes the partition door 18 as shown in FIG. (E). In parallel with this, the material to be heated W ₁ is extracted from the furnace by the extractor 8, the extraction port door 7 is closed, and the above steps are repeated to successively extract the materials to be heated W ₂ , W ₃ ... Do it.

In this way, after the heated material W ₁ is lifted by the extractor 8, the hearth 6 is rotated in the backward direction so that the subsequent heated material is positioned behind the partition door 18 and the partition door 18 is closed. In the open state of the door 7, the time during which the subsequent material to be heated is exposed to the cool air and the time when heat is radiated to the outside of the furnace are shortened, so that the temperature of the material to be heated and the heat loss from inside the furnace are controlled.

The present invention is not limited to the above embodiment, and for example, the present invention can be applied to a rotary hearth type heating furnace having no baffles 11 to 13. Further, although the above-mentioned embodiment describes the heating furnace having the extraction port 4 and the charging port 5, the present invention can be applied to a heating furnace having only one extraction port also serving as the charging port. In this case, the material to be heated may be charged with the partition door closed after the extraction shown in FIG. 2 (e), and the equipment cost can be reduced by using both the extractor and the charge machine.
Further, the opening position of the partition door 18 can be changed so as to be located at a predetermined small distance from the upper surface of the heated material of each lot according to the type (dimension) of the heated material processed in the heating furnace. This is particularly preferable because the heat loss from the furnace can be kept low at all times, but the door may be opened to a certain height position according to the material to be heated having the maximum height.

(Effects of the Invention) As described above, according to the present invention, the temperature drop of the subsequent heated material and the heat loss from the furnace during the extraction of the heated material are controlled, and the energy saving in the heating furnace operation is achieved. To be done.

[Brief description of drawings]

FIG. 1 is a horizontal sectional view of a rotary hearth type heating furnace showing an embodiment of the present invention, and FIGS. 2 (a) to (e) are sectional views taken along the line AA of FIG. 3 (a) to 3 (d) are equivalent to FIG. 2 showing the extraction method of the conventional rotary hearth type heating furnace. 1 ... Rotary hearth-type heating furnace, 4 ... extraction port, 6 ... hearth,
8 ... Extractor, 17 ... Soaking, 18 ... Partition door, 18
b: Lower end, W: Heated material, H: Vertical gap.

Claims (1)

[Claims] 1. A partition door, which is driven up and down between a closed door position where a lower end of the door reaches the hearth floor and an open door position which forms a vertical gap larger than the height of a material to be heated on the hearth floor, from an extraction port. It is installed in a position near the soaking zone to partition the inside of the furnace, and after the heated material is made to stand by behind the partition door, the partition door is opened and the hearth is rotated in the forward direction to lead the heated material. Is moved to the extraction port position and the heat-treated material is extracted by the extractor, and the hearth is lifted after the heat-treated material is lifted by the extractor, and the subsequent heat-treated material is moved to the above-mentioned manner. A method for extracting a material to be heated in a rotary hearth type heating furnace, wherein the material to be heated is sequentially extracted by moving the material to a position behind the partition door, closing the partition door, and repeating the above steps.