JPH02217101A - Method and equipment for rolling hot slab and hot rolling equipment - Google Patents

Abstract

PURPOSE:To prevent a rolled stock in rough rolling from interfering with a rolled stock in width rolling down and to carry out the rough rolling and the width rolling down simultaneously by rolling down the width while hot slab is supplied from the side of a reversible rough rolling mill to a heating furnace. CONSTITUTION:The heating furnace 1, a width rolling down device 2, a reversible or back pass type rough rolling mill 3 being a 1st rough rolling mill are arranged from the upstream of a line in this order. The slab 7 rolled down in width by the width rolling down device 2 receives, for example, a five-passes reverse rough rolling by the rough rolling mill 3. The slab 7 finished a 2nd pass rough rolling is rolled down in width by the width rolling down equipment as the slab 7 is supplied from the side of the rough rolling mill 3 to the side of the heating furnace 1. By this method, though the rough rolling by the rough rolling mill 3 and the width rolling down by the width rolling down equipment 2 are opened simultaneously, the rear end of the slab finished the 4th pass of the rough rolling and the front end of the slab in width rolling down do not interfere with each other. Consequently, the idle time can be minimized and the production efficiency can be improved.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a hot rolling installation, and in particular to a rolling method for a hot rolling facility in which a width reduction device is provided between a heating furnace and a rough rolling mill. and its hot rolling equipment.

[Conventional technology]

Conventionally, in hot rolling equipment, the width of the rolled material (hot slab) has been reduced using a width reduction device, and the width reduction device used is a tapered die with a parallel section. It is described in JP-A-59-101201.

[Invention or problem to be solved]

The publication only mentions the width reduction device and does not describe the equipment before and after it or the equipment layout, but if it is to be installed in an actual hot rolling facility, it should be installed in the heating furnace or the like. A first rough rolling mill (hereinafter simply referred to as a rough rolling mill) is considered.

By the way, the layout of the hot rolling equipment is determined based on the steel type, the dimensions of the rolled material, the rolling mill type, the production volume, and the like. For example, if the roughing mill is a reversible type or a backpass type, the table length between the heating furnace and the roughing mill is determined by the length of the rolled material after rolling in the roughing mill. The length is such that the rear end reaches near the heating furnace. Therefore, if the roughing mill is a non-reversible type, or if there is sufficient table length between the roughing mill and the heating furnace, this will not be a problem, or if the existing equipment is a reversible type or a back-pass type rougher. When introducing the above-mentioned width reduction device between the rolling mill and the heating furnace, the rear end of the rolled material being roughly rolled in the roughing mill and the tip of the rolled material being width reduced in the width reduction device interfere, so the rough rolling and width Rolling cannot be carried out at the same time, and width reduction must wait until the rough rolling is completed. For this reason, the processing time for one slab is the sum of the times required for the width reduction device and the roughing mill, resulting in a problem that the production volume decreases.

The purpose of the present invention is to avoid interference between the rolled material during rough rolling and the rolled material during width reduction, and to make it possible to perform rough rolling and width reduction at the same time, thereby reducing production volume even after the introduction of width reduction equipment. It is an object of the present invention to provide a method for rolling a hot slab and hot rolling equipment that does not cause the occurrence of.

[Means to solve the problem]

The above object is achieved by, when width-reducing a hot slab using a width-reducing device, width-reducing the slab while sending it from the roughing mill side toward the heating furnace side.

Further, the above object is to provide a side guide for the width reduction device at least on the side of the rough rolling mill, and to provide a width reduction device between the width reduction device and the rough rolling mill to send the hot slab toward the width reduction device. This is achieved by providing a conveying roller table consisting of two systems: a rough rolling roller table for conveying the hot slab to the rough rolling mill.

[Effect]

In the present invention configured in this manner, the slab subjected to width reduction by the width reduction device enters from the roughing mill side and exits toward the heating furnace side. As a result, even if rough rolling in the rough rolling mill and width reduction in the width reduction device are performed at the same time, the length of the slab roughly rolled in the rough rolling mill is short at the beginning of the rough rolling and width reduction, so the width reduction is reduced. On the roller table between the equipment and the rough rolling mill, the slab being roughly rolled and the slab being width rolled do not interfere.

In addition, in the later stages, the length of the roughly rolled slab becomes longer and occupies most of the roller table between the rolling mill and the width reduction device; The slabs do not interfere with each other in this case as well. In this way, by effectively using the roller table between the rough rolling mill and the width reduction device and by reversing the feeding direction to the width reduction device, rough rolling and width reduction can be achieved without interference between slabs. can be done at the same time.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 6.

FIGS. 1 to 3 are chronological diagrams showing the movement of a hot slab in the hot rolling equipment of this embodiment and the rolling method using the hot rolling equipment.

In the figure, the equipment line direction is from right to left, and the heating furnace 1, width reduction device 2, and reversible roughing mill 3, which is the first ¥fi rolling mill, are installed in this order from the upstream side of the line. A side guide 4 is provided on the rolling 11[3 side for guiding the slab to be width-reduced by the width-reducing device 2. Between the width rolling device 2 and the rough rolling device 8!3, two roller tables, a width rolling roller table 5 and a rough rolling roller table 6, are disposed, each of which rolls down the width of the slab by a drive device (not shown). It is driven to feed toward the device 2 and the rough rolling mill 3.

First, in FIG. 1, a slab 7 whose width has not yet been reduced is placed on the roller table 5 for width reduction, and a slab 7 whose width has been reduced is placed on the roller table 6 for rough rolling.
The slab 7 is then subjected to width reduction by the width reduction device 2, and the slab 7 is then subjected to five passes of reverse rough rolling in the rough rolling mill 3.

Figure 2 shows that the second pass of rough rolling of the slab 8 has been completed in the rough rolling mill 3, and the width reduction is performed while sending the slab 7 from the rough rolling mill 3 side toward the heating furnace 1 side. It is in a compressed state.

In FIG. 3, the fourth pass of rough rolling in rough rolling a3 has been completed, the width reduction has also been completed, and the slab 11 to be width rolled next has been extracted from the heating furnace 1. At the same time as the final fifth pass of rough rolling is started, the slab 7 that has undergone width reduction and the slab 11 that has just been extracted are conveyed downstream of the line, returning to the state shown in FIG.

As can be seen from Figures 1 to 3, as one culm is roughly rolled in the rough rolling mill 3, the length of the slab naturally becomes longer, and at the end of the fourth pass, the width reduction device 2 and the rough rolling mill 3 The rollers will occupy most of the table between them. In existing hot rolling equipment, the distance between the heating furnace 1 and the rough rolling mill 3 is determined by the length of the rough rolled slab, and if a width reduction device is further introduced there, the distance between the heating furnace 1 and the rough rolling mill 3 is determined by the length of the roller table. There are many cases where there is no room left. Therefore, when the width of the slab is reduced while being sent from the heating furnace 1 side toward the rough rolling mill 3 as before using equipment with such a short roller table length,
As shown in FIG. 4, even at the end of the fourth pass of rough rolling, the width reduction can only proceed by about 1/2 of the slab. This is because even if the width reduction is started early, the rear end of the slab 10 that has completed the fourth pass of rough rolling interferes with the tip of the slab 7 that is being width reduced.

In contrast, in this embodiment, even if rough rolling in the rough rolling mill 3 and width reduction in the width reduction device 2 are started at the same time, the slab 7
By sending the slab from the rough rolling mill 3 side toward the heating furnace 1 side and reducing the width, the rear end of the slab 10 that has completed the fourth pass of rough rolling and the slab that is undergoing width reduction, as shown in FIG. The tip of 7 will not interfere.

Now, the outline of this embodiment has been described above, but next we will specifically explain the cycle for processing slabs using the equipment arrangement shown in Fig. 5 and the slab dimensions and rough rolling schedule shown in the table shown in Fig. 6. do.

In FIG. 5, the horizontal direction represents the equipment arrangement, and the vertical direction represents the passage of time, and the position and dimensions of the material during width rolling and rough rolling can be seen. If the slabs are processed according to the rolling method of this example according to the table in FIG. 6, the slabs being roughly rolled and the slabs being width-reduced will be closest to each other at the end of the fourth pass of rough rolling, or will still be 3.7 m. There is a margin for this, and the width reduction can be completed before the completion of rough rolling, and the idle time between cycles is 5 seconds, making it possible to minimize the idle time.

On the other hand, when width reduction is performed from upstream to downstream of the line, the distance between the slab being rough rolled and the slab being width reduced at the end of the 4th pass of rough rolling is 1 m, as shown in Figure 7. Even so, the start of width rolling must be delayed by 2 B sec from the start of rough rolling, and the idle time between cycles is 33
Sec, and the production volume decreases.

As described above, according to this embodiment, rough rolling in the reversible rough rolling mill and width reduction in the width reduction device can be performed at the same time, and width reduction can be completed before the completion of rough rolling. This has the effect of minimizing time. Further, since the width reduction device can be installed while keeping the distance between the rough rolling mill and the heating furnace the same as before, the length of the equipment can be made compact.

Note that although the present invention has been described in detail with respect to hot rolling equipment using a reversible roughing mill, the present invention is equally applicable to hot rolling equipment using a backpass type roughing mill. be.

〔Effect of the invention〕

According to the present invention, the table between the reversible or back-pass type rough rolling mill and the width reduction device is effectively used, and rough rolling and width reduction can be performed simultaneously, so that the idle time between slab processing can be minimized. This has the effect of improving production efficiency and making the length of equipment more compact.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing the rolling state at the start of rolling of a hot rolling equipment according to an embodiment of the present invention, and FIGS. 2 and 3 are respectively the subsequent rolling states of the same hot rolling equipment. FIG. 4 is a plan view showing rolling conditions in a conventional hot rolling facility for comparison, and FIG.
FIG. 5 is an explanatory diagram showing a processing cycle of a rolling method according to an embodiment of the present invention, in which the vertical direction shows the passage of time, the horizontal direction shows the equipment arrangement, the position and length of the slab, and the sixth
The figure is a table showing the slab dimensions and rough rolling schedule in the same treatment cycle, and FIG. 7 is an explanatory diagram similar to FIG. 5 showing a treatment cycle using conventional hot rolling equipment for comparison. Explanation of symbols■... Heating furnace 2... Width rolling device 3... Reversible rough rolling mill 4... Side guide 5... Roller table for width rolling 6... Roller table for rough rolling 7 ~11...Slab applicant Hitachi, Ltd. Nisshin Steel Co., Ltd.

Claims (2)

[Claims] (1) In hot rolling equipment in which a hot slab width reduction device using a tapered mold having a parallel part is installed between a heating furnace and a reversible or backpass rough rolling mill, A method for rolling a hot slab, characterized in that when the hot slab is rolled down in width by a rolling device, the slab is rolled down in width while being sent from the roughing mill side toward the heating furnace side. (2) A hot slab width reduction device using a tapered die with parallel parts is installed between the heating furnace and the reversible or backpass rough rolling mill, and a side guide for the width reduction device is installed. Provided at least on the rough rolling mill side, between the width rolling device and the rough rolling mill, a width rolling roller table for sending the hot slab toward the width rolling device and a roller table for sending the hot slab toward the rough rolling mill. A hot rolling facility characterized by being provided with a conveying roller table consisting of two systems: a rough rolling roller table;