DE60108890T2 - PROCESS FOR FINAL WARM ROLLING - Google Patents

Description

technical area

The The present invention relates to a method for adjusting the Operating conditions for endless hot rolling.

State of technology

Usually comes in Rolling process for hot rolled sheet steel as follows: a slab is in one The oven is heated, the heated slab is added with a roughing mill rolled a sheet steel, and the sheet bar is then with a finishing mill rolled into a hot-rolled sheet. The slab, the sheet metal and the hot-rolled sheet is collectively used as rolling stock designated. So far, the pre-rolling mill rolled sheet steel rolled one at a time with the finishing mill. Such a procedure is known as discontinuous rolling. Recently it has been following methods marketable made: the back end of a previous sheet metal is between a roughing mill and a finishing mill each successively connected to the front end of a subsequent sheet bar, and the variety of resulting sheet steel is with the finishing mill rolled continuously without interruption. This method is known as endless rolling. While the actual finish rolling becomes discontinuous rolling and endless rolling performed individually.

Now is a method for determining rolling conditions in a conventional discontinuous rolling process will be described. An upper computer determines the rolling conditions based on information such as steel type, standard, size, product thickness, product width every rolled material. The rolled material is then a hot rolling line fed. A lower computer detects the position of the rolling stock at numerous Points in the hot rolling line.

Of the bottom computer provides the rolling conditions of a device, the is arranged behind the place where the rolling material detected is, according to predetermined rolling conditions. The rolled material is then fed to the downstream device.

At the Continuous rolling is a connection of the sheet together required. Exemplary bonding techniques are disclosed in Japanese Unexamined Patent Application No. 8-300008 and Japanese Unexamined Patent Application No. 7-24504, filed by the Applicant.

The Japanese untested Patent Application No. 8-300008 describes a laser welding device, in which a vertical alignment device on a jig for a preceding sheet bar and / or on a jig for a subsequent Sheet bar is provided. The Japanese Unexamined Patent Application No. 7-24504 describes a jig for connecting Sheet steel as follows: the rear end of a previous sheet bar and the front end of a subsequent sheet bar, both of which are heated are clamped vertically with arms individually so that between both Ends a gap is provided, and they will afterwards connected. Another jig with a balance holding system including Mounting plates for clamping via a Sheet steel with another sheet bar is described.

The device disclosed in Japanese Unexamined Patent Application No. 8-300008 requires a system for vertically aligning the connection ends for a preceding jig and / or a subsequent jig. Thus, there arises a problem that the device is complicated. If a subsequent sheet bar 12 thicker than a previous sheet bar 10 , is at a junction 11 the sheet steel formed a step. As in 1 is shown in a finishing mill, a force on the stage between the sheet bars in the direction shown in the figure from the upper roller 14 and the lower roller 15 is applied. As a result, a problem arises in that the transition point 11 between the subsequent sheet bar and the previous sheet bar may be destroyed.

2 shows a device disclosed in Japanese Unexamined Patent Application No. 7-24504. In 2 Designate reference numbers 16 and 17 the upstream upper and lower clamp and the reference numbers 18 and 19 denote the downstream upper and lower clamp. If a subsequent sheet bar is thinner than a previous sheet bar and both sheet bars clamped with mounting plates As a result, extending over the subsequent sheet bar and the preceding sheet bar, a problem arises in that the fixing plates are bent.

on the other hand the applicant has a method for setting conditions of Continuous rolling in Japanese Unexamined Patent Publication No. 10-5830 and in the Japanese unaudited Patent Application No. 11-169926. The Japanese Unexamined Patent Application No. 10-5830 describes a method in which a connection order of materials for Endless rolling is determined so that one in a finished sheet with a small diameter material to be rolled in the middle of Rolling order is rolled. The Japanese Unexamined Patent Application No. 11-169926 a process in which a rolling process is instantly discontinuous Rollers are switched when for Continuous rolling provided rolling materials not by continuous rolling can be treated. Thus, the rolling conditions for both continuous rolls and discontinuous Rolls previously determined. In the Japanese Unexamined Patent Application No. 10-5830 and Japanese Unexamined Patent Application No. 11-169926 Procedures do not solve the following problems: the Sheet metal described above may be destroyed, and the fixing plates holding mounting plates are bent.

disclosure the invention

The The present invention provides a solution to the conventional ones described above Problems ready. An object of the present invention is in it, a damage the mounting plates to avoid connection strength when Achieve rolling and reduce rolling stress.

In The present invention overcomes the above problems solved, that sheets, each having the same thickness, are rolled. In hot rolling, an upper computer determines the rolling conditions for a Each rolled material according to information, such as the steel type, the standard, the size, the product thickness and the Product width. When the rolling materials are subjected to endless rolling be leads a lower calculator performs the following calculations: the lower one Calculator compares the predetermined thickness of sheet bars for individual Rolling materials from the front material to the rear material and determines from these the smallest thickness. The above Problems are solved by Rolling done so is that the sheet bar thickness set to a minimum value of the same becomes. If so far a subsequent sheet bar is thicker than a preceding sheet bar, will force one step at the joint applied between the sheet bars of the rolls for finish rolling. As a result, there is a problem that the connection point possibly destroyed becomes. Furthermore, there is a problem that the mounting plates bent or destroyed can be when the step is clamped with the mounting plates. In the Present invention, the thicknesses of the sheet bars for a variety continuous rolling of rolling stock to the same value set. Therefore, the above problems do not occur.

3A and 3B show the effects of the present invention. As in 3A is shown, the joint is supplied smoothly in rolls for finish rolling. As in 3B is shown, the mounting plates 16 and 17 the jigs are not bent.

Short description the drawings

1 Fig. 11 is an illustrative drawing of a problem of a method disclosed in Japanese Patent Unexamined Patent Publication No. 8-300008, and shows a cross section in finish rolling.

2 Fig. 4 is an illustration drawing of a problem of a method disclosed in Japanese Unexamined Patent Application No. 7-24504, and shows a cross section of a clamped portion.

3A Fig. 3 is an illustration showing the effect of the present invention and a cross section in finish rolling.

3B Fig. 3 is an illustration showing another effect of the present invention and showing a cross section of a clamped portion.

4 Fig. 3 is an illustration showing an exemplary hot rolling line according to the present invention.

5 Figure 12 is a block diagram of an embodiment of a control unit according to the present invention.

6 is a flow chart and shows the treatment method of the above embodiment.

7 FIG. 12 is a diagram showing information on the rolling materials used in an embodiment of the present invention. FIG.

Best kind and manner of execution the invention

Now Be exemplary embodiments of the present invention with reference to the drawings in detail to be discribed.

With reference to 4 A contour of an exemplary hot rolling line for carrying out endless rolls is illustrated. Now, an endless rolling method using the hot rolling line will be described. A rear end 10e a preceding sheet 10 comes with a front end 12t a subsequent sheet 12 with a joining device 30 connected between a roughing mill 20 with three scaffolding and a finishing mill 40 is provided with seven scaffolding. The previous sheet 10 and the subsequent sheet 12 , which have been joined together, are treated continuously in finish rolling. A cutting tool 50 for rolling mills is behind the finishing mill 40 provided, and two reels 60 be behind the cutting tool 50 provided. Using the cutting tool 50 becomes the finished rolled material with the interconnected preceding sheet 10 and subsequent sheet 12 cut into sheets, each having a length, each of the winding capacity of each reel 60 equivalent. A rolled material positioned behind the point of intersection and another rolled material positioned in front of the point of intersection are wound separately on a reel, alternately.

In the endless finish rolling, the preceding plate 10 and the subsequent sheet 12 Rolled continuously without exposure, with stable rolling over the entire length is performed. This method is particularly suitable for a rolling material having a small thickness, which causes difficulty in introducing the rolling material between the rollers due to an unstable tip.

5 Fig. 12 is a block diagram of a control unit used for the present invention. As in 5 is shown, the operating conditions of devices in the hot rolling line of computers are set. Data such as the steel type, the standard, the rolling size and so on become for each slab, which is a rolling stock, with a job input terminal 80 entered. The data of the slab, for example, via a factory LAN 82 to an upper computer 70 Posted. The upper computer 70 Determines the rolling conditions, such as the rolling temperature, the stitching plan, the rolling speed, the inter-frame tension and the cooling speed, for each rolling stock. The upper computer sends the rolling conditions to a lower computer 72 ,

When the slab is inserted into the rolling line, the lower calculator reads 72 from the detection data output from the detectors arranged at some points in the rolling line. In 5 the detectors comprise a detector arranged after the rolling mill 24 , another arranged after the joining device detector 25 and another after the finishing mill arranged detector 44 , The detection data includes the temperature, the thickness and the width of the plate. The lower computer 72 simultaneously reads the actual operating data of the device. The device comprises the roughing mill 20 , the joining device 30 , the finishing mill 40 , the cutting tool 50 , the reels 60 and so on. The actual operating data include that by a hitch 22 of the roughing mill 20 and another adjusting device 42 the finishing mill 40 introduced rolling forces. A combination of the detection data output by the detectors and the actual operation data of the device is referred to as rolling stock data. The lower calculator calculates according to the rolling stock data 72 the operating conditions of the device located after the location where the rolling stock is currently located are such that the rolling material is rolled under rolling conditions coming from the upper computer 70 who receive the. The lower computer 72 sends operating state signals to each device based on the calculation results, thereby controlling the device.

The present invention will now be described in more detail by way of example. For example, in the case of discontinuous rolling operation, the lower calculator calculates 72 the operating conditions of the Finishing mill 40 that is, the rolling position and the rolling peripheral speed for each stand according to the rolling material data in the roughing mill so that finish rolling takes place below the upper calculator 70 received finish rolling conditions is performed. The rolling stock data during rough rolling includes the size and temperature of a sheet bar after rough rolling. The data is taken with the detector 24 , which is arranged after the roughing mill, recorded or according to the actual operating data of the roughing mill 20 calculated. On the other hand, for example, in a continuous rolling process, the preceding sheet becomes 10 through the joining device 30 with the following sheet metal 12 and then the lower calculator calculates 72 the operating conditions of the finishing mill 40 for the subsequent sheet metal 12 , After that the lower calculator calculates 72 the operating conditions of the finishing mill 40 so that finish rolling below that of the upper calculator 70 received finish rolling conditions as described above.

6 shows the entire method described above. In the present invention, the sheet thickness predetermined for the individual rolling materials is compared and set to a minimum value thereof.

In the one with the reference number 130 in 6 designated block, the sheet bar thickness is determined for each rolling stock. 7 shows a method for the determination. For each slab, the slab thickness becomes one in the upper calculator 70 stored setting table using data such as the steel type, the standard, the roll size, the command thickness after hot rolling and the command width after hot rolling, retrieved. Like also in 7 is shown, the sheet bar thickness is preferably recorded for each continuous rolling and discontinuous rolling.

The predetermined sheet bar thickness is entered in advance in the table. To produce products with excellent mechanical properties, such as for example, to obtain strength and elongation after rolling, The following conditions are required: (1) Reduction of the energy loss caused by radiation and (2) a high level of energy loss Temperature during finish rolling. Thereafter, the sheet bar thickness is preferable large. If However, the thickness of a sheet after finish rolling is low, the sheet bar thickness is preferably small in order to reduce the stress on the Reduce finishing mill. The sheet bar thickness is taken into account the above contradictory Conditions determined. The sheet bar thickness can only be discontinuous Rolling or for discontinuous rolling and for Continuous rolling can be determined.

In this specification, it is assumed that the number of rolling materials for endless rolls is n, and that the sheet bar thickness for each rolling material is determined according to the above logic as t ₁ , t ₂ , ..., t _n . A group consisting of a plurality of rolling materials for endless rolls is referred to as an endless unit. In the present invention, t ₁ , t ₂ , ..., t _n in the endless unit are compared with each other to replace a preset value with the following formula: Min (t 1 , t 2 , ..., t n ).

Min () denotes a function for selecting the smallest value among the plurality of variables in the parentheses. If the sheet bar thickness is determined only for discontinuous rolling, Min (t ₁ , t ₂ , ..., t _n ) can be determined for it. If the sheet bar thickness is determined for both discontinuous rolls and endless rolls, Min (t ₁ , t ₂ , ... t _n ) can only be determined for continuous rolls.

As described above, those for individual rolling materials predetermined sheet bar thicknesses, and the sheet bar thicknesses are set to their minimum value.

EXAMPLE

table 1 shows an exemplary process in which the thicknesses of sheet bars for discontinuous rolling be determined and determined the thicknesses of sheet bars for Endloswal zen thereafter become. The patterns shown in Table 1 were prepared as follows: The sheet bars of rolled materials Nos. 1 to 6, which are the same steel (low carbon steel) were placed in front of a finishing mill connected together and then continuously in finish rolling processed. In conventional discontinuous rolling was the thickness of a sheet bar for a each rolling stock determined. In contrast, the thicknesses the sheet bar in the endless rolling process to the minimum thickness of 30 mm (No. 4 in Table 4).

Table 1

Industrial applicability

According to the present invention, the sheet bar thicknesses of rolling materials in the unit are standardized. In conventional methods, when the thickness of a succeeding sheet bar is larger than that of a preceding sheet bar, there is a problem that a joint between sheet bars is broken due to a force applied to a finish rolling stage at the joint of rolls. Further, if the thickness of a subsequent sheet is smaller than that of a preceding sheet, there is a problem that fixing plates for clamping or clamping the step are bent or broken. However, according to the present invention, the compound and the finish rolling are as in 3 shown smoothly and smoothly.

Claims (1)

Method for hot rolling to perform under Rolling conditions based on rolling stock information, including the kind, the standard, the size, the Product thickness and the product width of the rolling materials previously determined with a rear end of a preceding sheet bar is connected to the front end of a subsequent sheet bar, to treat the rolling materials by endless finish rolling, the method comprising the steps of: Comparing the sheet bar thickness, the for single rolling stock has been predetermined in an endless plant, in the rolling materials in the order of rolling one Beginning are arranged to an end Adjusting the thickness the sheet metal to a minimum value of the same, and Perform the endless finish rolling.