JPH02149612A - Device for charging steel slab into heating furnace - Google Patents

Abstract

PURPOSE:To minimize opening area of a furnace at the time of charging a steel slab and to reduce heat loss in the furnace by arranging a lower door for closing/opening the lower opening part in the furnace while linking with ascent/descent of a charging beam at the time of charging the steel slab into the heating furnace. CONSTITUTION:When the charging beam 6 laying the steel slab 1 advances to the inlet of the furnace, at first, the upper door 9 is ascended and at the same time, the beam 6 is ascended to insert the beam 6 into a charging hole 8. Successively, the beam 6 is descended and after laying the steel slab 1 on skid, the beam 6 is retreated and returned back to the original position. Then, the lower door 16 is arranged at lower part furnace wall 3b, too and by driving an eccentric roller 20 while linking with ascent/descent and shift to front/rear of the beam 6, the lower door 16 is ascended/descended through a chain 22, sprocket 19 and chain 18 and the area of the opening hole 7 in the heating furnace at the time of charging the steel slab 1 is held to minimize, to prevent the lowering of the furnace temp. caused by invasion of cold outer air. By this method, the heat loss in the heating furnace is reduced and also, scale loss caused by rise of oxygen concn. in the furnace is improved.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a steel billet charging device for charging steel billets into a heating furnace, etc. More specifically, when charging steel billets, This invention relates to a steel billet charging device that includes a lower door that closes the lower opening to reduce heat loss.

[Prior Art] When charging a steel billet into a billet heating furnace, generally, as shown in FIG. It is charged into the heating furnace 3 by a charging machine 4 installed at .

The charging machine 4 has a plurality of charger beams 6 (in this example, 4
Although not shown, each beam 6 can be raised and lowered horizontally at the same time, or can be moved back and forth, so that the steel billet l can be moved into the heating furnace 3.
It is configured to be loaded into.

In a heating furnace 3 using such a side-loading type charger beam 6, there is only one opening door, and the opening can be adjusted by moving this upper door in accordance with the movement of the beam 6. All it did was move it up and down to minimize it.

In such a structure, the lower side of the beam 6 remains open, and outside air often enters during charging of steel pieces or hot air blows out from inside the furnace).

Figures 5 and 6 show conventional door structures, with Figure 5 being a cross-sectional view taken along line C-C in Figure 4, and Figure 6 being a cross-sectional view taken along line D-D in Figure 5. and FIG. 7 is an explanatory diagram of the operation of the lower door. A rectangular opening 7 for charging the billet 1 is provided between the upper furnace wall 3a and the lower furnace wall 3b, and the lower furnace wall 3b has an entrance for the charger beam 6 of the billet charging machine 4. 8 is provided in four locations.

The upper door 9 is suspended from the upper part of the furnace by a chain 10, and the chain IO is hung on a crankshaft 11.

When the crankshaft ll is rotated in response to the charging trajectory 12 of the beam 6 as shown by the broken line in FIG. 6, the upper door 9 moves along the trajectory 1 shown by the dashed line in FIG.
The opening 7 of the loading port is opened and closed by moving up and down in a 3-line pattern. When charging the steel piece l, the beam 6 rises and lifts the steel piece l, and the upper door 9 gradually rises from point P and fully opens at point Q. In this state, the beam 6 is charged into the heating furnace 3, and the beam 6 is placed in order to place the steel billet l on the skid 14.
is lowered and at the same time the upper door 9 is lowered. When reaching the R point, the upper door 9 is maintained in a half-open state until the beam 6 retreats out of the category 3, and after the retreat is completed, the upper door 9 is lowered and the opening 7 becomes fully open.

[Problems to be Solved by the Invention] In the conventional technology as explained above with reference to FIG. As a result, cold air from outside enters the furnace and lowers the furnace temperature, and the oxygen concentration inside the furnace increases, causing problems such as increased scale loss.

The present invention was proposed in order to solve the above-mentioned problems, and it is a steel billet loading system equipped with a lower door that minimizes the opening area of the furnace when charging billets and reduces heat loss. The objective is to provide an input device.

[Means for Solving the Problems 1] The present invention solves the above-mentioned problems, and is applied to a billet charging device in a heating furnace, and employs the following technical means. Namely.

A lower door was installed to close and open the lower opening of the heating furnace when charging billets in conjunction with the rise and fall of the charger beam.

[Function] In the present invention, a lower door is provided in addition to the existing upper door to close and open the lower opening of the heating furnace when charging billets in conjunction with the rise and fall of the charger beam. During charging, the opening area of the heating furnace can be minimized by operating the upper door. Therefore, it has become possible to significantly improve the problem of external cold air entering the furnace, lowering the furnace temperature, and increasing scale loss due to an increase in the oxygen concentration in the furnace.

[Example] An example of the steel billet charging device of the present invention will be described based on the drawings. Figure 1 is a front view of the vicinity of the opening of the billet charging device, Figures 1 (a) and (b) show the state before and during charging, respectively, and Figure 2 (a). ) and (b) show a cross-sectional view taken along the line A-A and taken along the line B-B in FIGS. 1(a) and (b), respectively.

As shown in FIGS. 1 and 2, a rectangular opening 7 for charging the steel billet 1 is provided between the upper furnace wall 3a and the lower furnace wall 3b, as in the conventional example.

Further, four entrance ports 8 for the charger beam 6 are provided in the lower furnace wall 3b. The upper door 9 is suspended from the upper part of the furnace by a chain 10, and the chain 10 is hung on a crankshaft 11, and the crankshaft 11 is rotated by a motor to raise and lower the upper door 9, similar to the conventional example. be.

The feature of the present invention is that a lower door 16 is provided in addition to the upper door 9,
The raising and lowering of the lower door 16 is linked to the raising and lowering of the beam 6 so that the area of the opening 7 when charging the steel slabs l into the furnace is minimized.

The lower door 16 is connected to a sprocket 19 via a support stand 17 and a chain 18. On the other hand, an eccentric roller 20 for raising and lowering the charger beam 6 is connected to a sprocket 19 by a chain 22 via an eccentric roller shaft 21.
is connected to. Therefore, by rotating the rotation shaft (not shown) of the sprocket 19, the lower door 16 can be raised and lowered in conjunction with the raising and lowering of the beam 6. The upper limit position of the lower door 16 can be changed by adjusting the height of the support stand 17.

Next, the operation of charging the steel billet 1 will be explained. As shown in FIG. 2(a), the steel billet 1 is placed on a beam 6 and transported to the furnace entrance.

First, the upper door 9 is raised. At the same time, when the beam 6 is inserted into the entrance port 8, the beam 6 is raised so that the lower surface of the steel billet l does not come into contact with the upper surface of the lower furnace wall 3b. At this time, the lower door 16 also rises. The amount of rise of the beam 6 at this time is set to the minimum necessary amount.

The upper door 9 takes into consideration the maximum thickness t of the steel billet l to be charged,
It is raised to the required minimum height that allows charging of the steel billet 1 and then stopped.

Next, the beam 6 is advanced into the furnace, and after the steel billet 1 is charged at a predetermined position, the beam 6 is stopped.

The beam 6 is lowered into the entrance 8 and the steel billet 1 is placed on a skid (not shown) in the furnace.

At this time, the lower door 16 is lowered by the same amount as the lowering amount d of the beam 6 to avoid contact with the beam 6. At the same time as the beam 6 descends, the upper door 9 is
Lower by the amount equal to the sum of

The beam 6 is moved back and taken out of the furnace.Then, the upper door 9 is lowered and the opening 7 is closed.The series of billet charging operations is then completed.

A flow sheet for the above charging operation is shown in FIG. In addition,
In Fig. 3, upper door 9 and lower door I are shown for simplicity.
The logical configuration is such that the vertical speeds of No. 6 and No. 6 are the same. Note that the determination of whether the beam 6 has entered the furnace is made by calculation, and other determinations are made by limit switches.

[Effects of the invention J The present invention has the following excellent effects.

■It has become possible to significantly reduce thermal loss from the charger beam loading port 6.Sequence control of the device is easy, and the lower door can be made small, so equipment costs are low and cost is low. The cost is high.

[Brief explanation of the drawing]

Figure 1 is a front view of the vicinity of the opening of the billet charging device, Figures 1 (a) and (b) show the state before and during charging, respectively, and Figure 2 (a). ) and (b) are respectively shown in Fig. 1(a).
3A and 4B are a cross-sectional view taken along the line A-A and a cross-sectional view taken along the line B-B in FIG. FIG. 3 is an operation flow sheet of the present invention, and FIG.
6 to 6 are explanatory diagrams of the conventional example, FIG. 4 is a charging system diagram, FIG. 5 is a sectional view taken along the line C-C in FIG. 4, and FIG.
FIG. 3 is a sectional view taken along the line DD in the figure and an explanatory diagram of the opening/closing operation of the lower door relative to the time axis. l... Steel billet 2...-Roller table 3...Heating furnace 3a...-Lower furnace wall 3b--Lower furnace wall 4--Charging machine 5...-Loader 6...Beam 7 ...Opening 8--Entry port 9--Upper door 10--Chain 11--Crankshaft 12--Charging trajectory 13---Trajectory 14...-Skid 15...--Hearth Line 16...Lower door 17...Support I8...Chain 19...Sprocket 20...Eccentric roller 21...-Eccentric roller shaft 22...Chain P, Q, R...Point t ...thickness of steel billet

Claims (1)

[Claims] 1. A steel billet charging device for a heating furnace, characterized in that the steel billet charging device in a heating furnace is provided with a lower door that closes and opens a lower opening of the heating furnace during charging of billets in conjunction with the rise and fall of a charger beam. Single loading device.