JPH0312128B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a split-type walking beam furnace that can absorb fluctuations in operating conditions during steelmaking → continuous casting machine (hereinafter referred to as C/C) → hot billet conveyance → heating furnace → rolling. It is related to.

Generally, C/C process and R process (hot rolling process)
There are cases where the manufacturing capacity and rolling capacity of C/C are almost the same, and cases where the manufacturing capacity and rolling capacity of C/C are different. There are two ways to transport the pieces to the heating furnace:
In some cases, the rolling process may be carried out almost continuously for several tens of hours, and in any case, the rolling process may be temporarily stopped due to rolling mill roll changes, C/C mold roll changes, etc. , C.
There are times when C is temporarily stopped, that is, during unsteady operation. Therefore, the heating furnace located between the C/C process and the R process is required to serve as a buffer zone that absorbs operational fluctuations during this unsteady operation.

That is, when rolling is stopped, slabs (hot slabs) continuously transported from C and C are continuously charged into the furnace, and at the start of rolling, they are immediately transferred to the furnace at an extraction pitch corresponding to the rolling capacity. On the other hand, when the continuous caster is stopped, it operates continuously without stopping the rolling process, and when the continuous caster is restarted, it is extracted according to the capacity of the continuous caster. There is a need for a heating furnace in which slabs (hot slabs) can be continuously charged into the furnace and in which "empty zones" in the furnace can be minimized.

By the way, as a heating furnace having the function of the buffer zone, Japanese Patent Application Laid-open No. 109412/1982 and Japanese Patent Application Laid-open No. 53-1989
Split-type walking beam furnaces have been proposed as disclosed in Publication No. 142906, etc., but in all of them, slabs are continuously conveyed from a continuous casting machine to a heating furnace, and in addition,
If the rolling mill is operated in accordance with the production capacity of the continuous casting machine, and unsteady operation occurs such as stopping the rolling mill or stopping the continuous casting machine, the slab (heated (piece) cannot be inserted into the furnace. Therefore, not only is a place and equipment required to store the slabs, but the slabs must be cooled, resulting in heat loss.
On the other hand, when the continuous caster is stopped, rolling operations can be continued by extracting the slabs from the furnace for a certain period of time, but when the continuous caster is restarted, there are no slabs in the furnace. Therefore, there is a problem in that the rolling operation has to be temporarily stopped.

The present invention was made as a result of various studies regarding the above points, and is a split-type walking beam furnace in which each split moving beam is provided with a horizontal drive mechanism and an elevating drive mechanism. The phase of both moving beams in the furnace width direction is made different at the dividing part of the extraction side divided moving beam, and the effective horizontal stroke amount in the horizontal drive mechanism of the charging side divided moving beam is set as the reference horizontal stroke amount during normal conveyance. The object of the present invention is to provide a split-type walking beam furnace which is larger in size and has a servo function in the horizontal drive mechanism so that the ascent start position, the descent start position, and the horizontal stroke amount can be varied.

Next, the present invention will be explained with reference to the drawings which are one embodiment.

Figures 1 and 2 show a split type walking beam furnace (hereinafter referred to as a split type W/B furnace) of the present invention.
A schematic plan view and cross-sectional view of the slab (hot slab) placed between the C/C process (continuous casting process) and the R process (rolling process) and transported from the C/C process.
W is loaded using a charging machine such as a pusher (not shown).
While charging is carried out at a predetermined position on the fixed beam 1 of the split type W/B furnace T, it is sequentially transported to the extraction side by the rectangular movement of the moving beam 2 in the furnace, where it is heated to a rolling degree, and the predetermined extraction is carried out. sent to the location. Then, it is placed on an extraction table by an extractor (not shown) and transported to the R process.

The moving beam 2 of the split type W/B furnace T includes a charging side moving beam 2A and an extraction side moving beam 2 in the furnace length direction.
B and each moving beam 2.
A, 2B are provided with an elevating drive mechanism 3 consisting of an eccentric wheel etc. that moves each moving beam 2A, 2B up and down, and a horizontal drive mechanism 4 consisting of a hydraulic cylinder etc. that moves each moving beam 2A, 2B horizontally. We are prepared.
Further, the charging side moving beam 2A is provided with a member 9 having a vertically elongated hole 10, into which the head portion 5 of the hydraulic cylinder 4, which is the horizontal drive mechanism, is connected via a pin 6. At the same time, it is held via wheels 8 by a guide device 7 for preventing upward and downward vibration. The hydraulic cylinder, which is the horizontal drive mechanism, has a standard horizontal stroke amount (S ₁ = 440
It has an effective horizontal stroke amount of four times (S ₂ = 1760) as well as a servo function (not shown).
This servo function allows variable speed, horizontal stroke amount, and drive base point to be adjusted arbitrarily.

In addition, 13A is a support post of the charging side moving beam 2A, 13B is a support post of the extraction side moving beam 2B, 14A is a post support beam of the charging side moving beam 2A, and 14B is a post support beam of the extraction side moving beam 2B. , 16 are long holes provided in the hearth 15 for moving the support post.

Therefore, as shown in FIG. 3, the charging side moving beam 2A and the extraction side moving beam 2B are operated at a standard stroke amount S ₁ during normal operation with the end surfaces of each moving beam 2A and 2B facing each other. In addition to synchronized driving, during unsteady operation, as shown in Figures 4 A to C,
That is, when there is a space for the steel billet at the rear end of the extraction side moving beam 2B and the billet is placed in the space by the loading side moving beam 2A (Fig. 4A),
If there is no space in the extraction side moving beam 2B and there is space at the tip of the charging side moving beam 2A (Figure 4B) or if there is no space (Figure 4C), the loading side moving beam 2A obtains an arbitrary horizontal stroke amount within the range of its maximum stroke S ₂ , and also sets the drive base point (ascent start position, descent start position), forward end, and backward end at any position within the maximum stroke amount range. It will be held in

Next, in the hot rolling line where the split type W/B furnace is installed, the rolled material (6.25 pieces/piece) W cast in the C/C is transferred from the C/C to the split type W/B furnace at 225 t/H. While being charged into the furnace T, it is continuously supplied to the rolling mill set at a rolling capacity of 225t/H (Fig. 5A), and when the rolling process is stopped, such as when rolling rolls are changed, or , operations when the C/C process is stopped, such as C/C mold change work, will be explained.

The maximum heating capacity of the W/B furnace T is 300t/
Assume that 12 pieces of steel can be loaded on the charging side moving beam 2A at H.

First, a case will be described in which the rolling roll change operation time is set to 20 minutes and the rolling process is stopped during this time.

Start of rolling roll change work (rolling line stopped)
One hour in advance, the charging side moving beam 2A and the extraction side moving beam 2B can be driven independently, and the rolling capacity is increased to 300t/H (extraction pitch: 75 seconds/hour).
225t/H hot plate manufactured by C.C.
(Charging pitch: 100 seconds/piece), while the extraction pitch (75 seconds/piece) corresponds to the rolling capacity.
Extract continuously outside the furnace at a rate of 2 seconds/unit).

Next, the charging side moving beam 2A and the extraction side moving beam 2B were each driven independently to charge the steel billets at 225t/H (charging pitch: 100 seconds/piece) while heating them to the rolling temperature. 300t/H of steel pieces
(Extraction pitch: 75 seconds/piece) After 1 hour of extraction, the number of steel billets charged was 36, but
The number of steel pieces extracted is 48, and the moving beam on the charging side is 2A.
No steel piece is placed above it (5th
(See figure B). In this case, charging pitch (100 seconds/
Even when the extraction pitch (75 seconds/piece) is different, the steel piece on the extraction side moving beam 2B is
In order to always maintain a predetermined interval, the steel billet at the top position on the charging side moving beam 2A from which one steel billet has been extracted must be transferred to the last position on the extraction side moving beam 2B. It will not happen.
Also, as a matter of course, the charging side moving beam 2
The arrangement of the steel pieces located on A inevitably takes on various forms over time. Therefore, the horizontal stroke amount of the charging side moving beam 2A, the ascending start position or lowering start position in rectangular movement, and the number of rectangular movements are determined by the leading steel material of the charging side moving beam 2A and the end of the extraction side moving beam 2B. The control is based on the distance from the tail steel.

Then, when the rolling roll change operation is started and the extraction of steel pieces is stopped, the extraction side moving beam 2
The steel piece located on B is in an idling state. On the other hand, the steel billets from C and C continued to be 225t/
The material is charged into the furnace at a charging pitch of 100 seconds/piece (see Figure 5C).

When the rolling roll change work is completed (20 minutes after the rolling line is stopped), the steel billets from C and C are 12
The charging side moving beam 2A will be fully loaded with steel slabs, and in this state the rolling capacity will be returned to normal operation, that is, the rolling capacity is 225t/H (extraction pitch: 100 seconds/piece). (See Figure 5A).

Next, due to the mold change work of C and C,
A case where C/C is stopped for one hour will be explained.

When the conveyance of slabs produced in C and C to the furnace is stopped due to mold change work in C and C, the rolling capacity is reduced to 300t/h (extraction pitch:
In addition to changing to 75 seconds/piece, cold material (6.25t/piece)
(Charging pitch: 75 seconds/piece) is charged into the furnace at a rate of 300t/H (charging pitch: 75 seconds/piece), and the furnace is operated in a mixed state of cold material and hot material (see Figure 6A).

When the refrigerant is fully loaded on the charging side moving beam 2A, the charging of the refrigerant is stopped, and
Increased rolling capacity to increase heating time of cold material
Change the speed to 100t/H (extraction pitch: 225 seconds/roll) and continue the rolling operation (see Figure 6).

One hour after the C/C is stopped, that is, when the C/C is restarted, all the cold material on the charging side moving beam 2A has been transferred onto the extraction side moving beam 2B, and the hot pieces from the C/C are transferred to the extraction side moving beam 2B. When the material is transported to the furnace, the charging side moving beam 2A and the extraction side moving beam 2B are respectively driven independently (see Fig. 6C).

Then, the hot pieces produced at 225t/H in C・C are charged into the furnace at a charging pitch of 225t/H, and at the same time, at an extraction pitch of 100t/H (225 seconds/piece).
At this point, it moves to a state where it is extracted outside the furnace.

In this case, even if the charging pitch (100 seconds/piece) and the extraction pitch (225 seconds/piece) are different,
Moreover, since the steel slabs on the extraction side moving beam 2B always maintain a predetermined interval, when one steel slab is extracted, the next steel slab on the charging side moving beam 2A is moved. Before being extracted, it must be transferred to the rearmost position of the extraction side moving beam 2B. In addition, since charging and extraction are performed in parallel with a time difference, the arrangement of the steel pieces located on the charging side moving beam 2A is
It will take various forms as shown in Figure 4C.

Therefore, the horizontal stroke amount of 2A on the charging side moving beam, the ascending start position or descending start position in rectangular movement, and the number of rectangular movements depend on the presence or absence of a space at the rearmost end of the extraction side moving beam 2B and the charging. Depending on the presence or absence of a steel piece at the tip of the side moving beam 2A, a servo function is activated to make adjustments as appropriate. That is, when the first hot piece is charged after restarting C・C, the charging side moving beam 2A is made to perform rectangular motion multiple times, the horizontal stroke amount is made larger than the reference stroke S ₁ , and the next Before the extraction material is extracted outside the furnace, the extraction side moving beam 2B is moved to the rearmost position. Thereafter, the hot pieces that are sequentially charged into the furnace (100 seconds/piece) are transported to the extraction side depending on the conditions in the furnace described above.

Then, 20 minutes after C・C restarts,
The hot pieces are fully loaded on the charging side moving beam 2A (see FIG. 6D).

At this point, the charging side moving beam 2A and the extraction side moving beam 2B are brought into the synchronous driving state (state in Fig. 3) again, and the rolling capacity is returned to the steady operating state of 225t/H ( (See Figure 5a).

Above, we have explained the operating method during unsteady operation of a hot rolling line that employs the decomposition type W/B furnace of the present invention, but to summarize the functions of the split type W/B furnace that enables this unsteady operation: B Charging side moving beam 2A and extraction side moving beam 2
Each can be operated independently from B, and
The effective horizontal stroke amount of the moving beam 2A on the charging side can be made larger than the horizontal stroke during normal operation during unsteady operation, and the amount of moving beam 2A on the extraction side
The point of motion can be arbitrarily determined prior to the equivalent motion with B.

In the above embodiment, a furnace was described in which the moving hearth was divided into two parts, but the charging side moving beam 2
The extraction side moving beam 2B other than A may be moved as necessary.
It may be further divided. Further, the horizontal movement drive mechanism 4 is not limited to a hydraulic cylinder, and other types may be used.

As is clear from the above explanation, according to the present invention, the movable hearth of the heating furnace is divided into at least two parts in the furnace length direction, and the movable hearth of the heating furnace is divided into at least two parts, and the movable hearth of the heating furnace is divided into at least two parts, and the movable hearth of the heating furnace is divided into two parts, and the movable hearth is moved in both directions by the divided parts of the charging side divided moving beam and the extraction side divided moving beam. The phases of the beams in the furnace width direction are made different, and the effective horizontal stroke amount of the horizontal drive mechanism of the charging side split beam is made larger than the standard horizontal stroke amount, and the servo function is used to set the ascent start position, descent start position, and Since the horizontal stroke amount is adjusted, the empty zone of the furnace can be minimized during unsteady operation such as when the rolling line is stopped or the continuous caster is stopped, and the rolling operation can be made continuous. It is something.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view of a two-part walking beam furnace according to the present invention, FIG. 2 is a partially enlarged sectional view of FIG. 1, and FIG. 3 is an explanatory diagram of the driving state of the moving beam during steady operation. Figures 4A to 4C are explanatory diagrams of the driving state of the moving beam during unsteady operation, and Figures 5A to 5C are diagrams explanatory of the driving state of the moving beam when the rolling process is stopped. 6A to 6D are explanatory diagrams of the driving state of the moving beam when the continuous casting process is stopped. 1A...Fixed beam, 2A...Charging side moving beam, 2B...Extraction side moving beam, 3...Elevating drive mechanism, 4...Horizontal movement drive mechanism.

Claims (1)

[Claims] 1 In a split-type walking beam furnace in which each split moving beam is equipped with a horizontal drive mechanism and a lifting drive mechanism, the charging side split moving beam and the extraction side split moving beam are separated in the furnace width direction of both moving beams. and the effective horizontal stroke amount of the horizontal movement drive mechanism of the charging side divided moving beam is made larger than the reference horizontal stroke amount during normal conveyance, and the horizontal movement drive mechanism is provided with a servo function. A split-type walking beam furnace, characterized in that a rise start position, a fall start position, and a horizontal stroke amount are variable.