JPH08257603A - Steel plate with variable thickness that has a horizontal step for displaying the cut in the longitudinal direction - Google Patents

Abstract

PURPOSE: To simplify blank layout, to enhance the accuracy of sheet stock thickness management and to improve productivity by forming horizontal step parts for indicating cutting at both longitudinal ends of a stock thickness-changing steel sheet to clarify the start point and standard points of the blank layout at the time of rolling this steel sheet. CONSTITUTION: The horizontal step part 3 for indicating the cutting part is first formed by rolling at the front end of the stock thickness-changing steel sheet 1 at the time of rolling the stock thickness-changing steel sheet 1. The stock thickness-changing steel sheet 1 is then rolled to a tapered shape and thereafter the horizontal step part 3a for indicating the cutting part is formed by rolling at the rear end, the contact points of the horizontal step parts 3, 3a and the tapered part are cut to prescribed shapes by an automatic shearing machine or manpower after rolling to for products. The junctures to the stock thickness-changing regions are also provided respectively with the horizontal step parts 3, 3a for displaying the cutting even in the case plural pieces of the stock thickness-changing regions are formed by rolling within the same rolled steel sheet in the longitudinal direction of the stock thickness- changing steel sheet 1. The length in the longitudinal direction of the steel-sheet of these horizontal step parts 3, 3a suffices with the length at which these parts are detectable as the step parts; 50 to 200mm is sufficient.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steel sheet having a plate thickness change having a horizontal step portion for displaying a cut portion in a longitudinal direction.

[0002]

2. Description of the Related Art As a plate thickness changing steel plate whose plate thickness changes in the longitudinal direction (rolling direction) of a thick steel plate, there is, for example, a taper plate whose plate thickness is sequentially changed. When manufacturing the taper plate, a plate thickness difference is given by a plurality of passes (rolling), and the flatness is ensured by controlling the in-plate deviation such as crown and the deviation between passes within the shape maintaining range. A high precision rolling method utilizing an automatic sheet thickness control circuit for rolling is disclosed in Japanese Patent Application Laid-Open No. 1-218711. By this rolling method, it is possible to take various patterns of variation in sheet thickness, and in the longitudinal direction of the steel sheet. It is possible to perform highly accurate rolling while suppressing the occurrence of strain.

[0003]

In the rolling of the tapered plate of the steel sheet as described above, if the maximum thickness and the minimum thickness of the tapered portion are set and the rolling is performed, the taper rate changes depending on the length of the steel sheet. If the taper ratio is controlled by keeping the taper ratio constant, a rolling-up part in which the leading end and the rear end of the rolled steel sheet in the rolling direction are locally thickened,
Precision of taper rate and maximum thickness, minimum thickness deviates greatly.
This applies not only to the tapered plate but also to, for example, a corrugated steel plate forming a corrugation in the rolling direction.

When such a steel plate profile is obtained, the starting point and reference point for cutting out the product become unclear. Therefore, after measuring the plate thickness profile of the entire steel plate in the length direction (rolling direction), The planing will be decided, resulting in poor work efficiency and low productivity. In addition, since it is difficult to identify the position in the longitudinal direction (rolling direction) where the actual strip thickness is the target strip thickness in the rolling process, it is extremely difficult to manage the actual strips and it is difficult to learn between slabs and passes. Quality cannot be controlled because the thickness cannot be controlled accurately. For this reason, since it is difficult to determine the contact point in the steel plate with varying thickness that is a combination of steel plates of a plurality of products, the contact point becomes one point, and it is difficult to design the tie in the same rolled steel plate. Therefore, not only automatic cutting by shearing is not possible, but also in off-line cutting such as gas cutting, work efficiency is significantly reduced and it is not possible in actual operation, the yield of the product is greatly reduced, and the rolling unit becomes smaller and There is a problem that the efficiency of other work (operation) is also greatly reduced. The present invention has been made in order to advantageously solve such a problem, by forming a horizontal step portion for the cutting portion display in the longitudinal direction of the plate thickness change steel plate, to solve the above problems It is intended.

[0005]

The feature of the present invention resides in that a horizontal step portion for displaying a cut portion is formed by rolling at both ends in the longitudinal direction of a steel plate having a changed thickness. A steel plate with a variable thickness having a horizontal step portion for displaying the parts.
And a plurality of plate thickness change regions are formed by rolling in the same rolled steel plate in the longitudinal direction of the plate thickness change steel plate, and horizontal step portions for displaying cut portions are respectively formed by rolling at the plate thickness change region forming connection parts. It is a steel plate with varying thickness having a horizontal step portion for displaying a cut portion in the longitudinal direction which is a feature.

[0006]

[Function] In the tapered plate, the specified product minimum thickness,
It is general to give a specified product maximum thickness, a specified product width, a specified product length and their respective tolerances. Therefore, in rolling, if the above-mentioned dimensions are rolled, the product will be satisfactory. However, in general, when a steel slab is rolled into a tapered plate, the product is not manufactured if the dimensions are below the tolerance. Therefore, the steel slab to which a certain proportion of weight is added is rolled. Therefore, the specified product width and the specified product length are larger than the specified product dimensions, and the product is cut off slightly to reduce the yield. Further, as another steel plate with a changed thickness, for example, a corrugated steel plate can be similarly described as described above.

In the taper plate 1 as shown in FIG. 4, when a specified product minimum thickness, a specified product maximum thickness, and a specified product width are rolled with a steel piece to which a certain proportion of weight is added, rolling is performed as indicated by a broken line. The specified product length becomes longer in proportion, and either the specified product length, the specified product minimum thickness, or the specified product maximum thickness deviates from the tolerance or approaches the upper and lower limits of the tolerance. In order to avoid this, either the weight addition allowance should be designed accurately for the weight of unnecessary parts such as cropping, or the addition should be expanded to the specified product width and rolled, but the aim of rolling and billet design However, the precision is extremely poor, and it is difficult to roll as a satisfactory product. As another workaround, as shown in Fig. 5, the amount corresponding to the additional weight is apportioned so that the minimum rolling thickness of the taper plate is smaller than the specified minimum product thickness and the maximum rolling thickness of the tapered plate is larger than the specified maximum product thickness. There is also a method of rolling, but this determines the rolling dimension according to the actual weight of the billet, so the product can be rolled without departing from the dimensional tolerance, and after the tenter rolling, it can be rolled according to the actual track width, the minimum target rolling thickness, the maximum rolling It is also possible to modify the target thickness appropriately.

In the rolling of such a thick steel plate, even if the automatic plate thickness control using the hydraulic roll gap control method is carried out, the thickness generated at the front and rear ends in the longitudinal direction becomes locally thick. Since it is not possible to eliminate a, the detailed plate thickness profiles of FIGS. 4 and 5 are as shown in FIGS. 6 and 7. In FIG. 6, since the thickness jump portion a is included in the designated product length, the tolerance is easily deviated, and even if the tolerance falls within the tolerance, it is possible to judge whether or not the designated product minimum thickness and the designated product maximum thickness are satisfied. Therefore, it is extremely inefficient to determine whether these are satisfied and the target taper rate is obtained, because it is necessary to measure at least the thickness a profile of both ends and the thickness profile of the area where the rate of change of thickness is constant. . On the other hand, in the embodiment shown in FIG. 7, both ends of the longitudinal direction are cut so that the product is rolled longer than the specified product length of the taper plate 1 to become the specified product length, the specified product minimum thickness, the specified product maximum thickness, etc. It is to be dimensioned. By doing so, the thickness jump portion a is eliminated as described above, but the actual thickness with respect to the minimum target rolling thickness and the actual thickness with respect to the maximum rolling target thickness cannot be accurately obtained at the position where the thickness jump portion a is removed. That is, learning between passes (rolling time) and between steel bills becomes impossible, and it becomes difficult to control the plate thickness with high accuracy.

Next, in the corrugated steel sheet (corrugated plate) 1 having a corrugated shape in the longitudinal direction, as shown in FIG. 8, the thickness of the corrugated steel sheet 2 generated at the front and rear ends in the longitudinal direction during rolling is It is not possible to eliminate the thickness jump portion a that locally thickens, and by cutting the both end portions in the longitudinal direction as the designated product length and the designated product thickness at both end portions in the longitudinal direction are obtained, the jump portion a disappears. . However, it becomes impossible to obtain accurate values of the actual thicknesses of the both end portions with respect to the intended rolling thickness at the positions where the thickness jump portion a is removed. Therefore, it becomes impossible to learn the pass time (rolling time) and between the steel pieces, and it becomes difficult to control the plate thickness with high accuracy as in the taper plate.

In the present invention, however, the horizontal step portion for displaying the cut portion formed in the lengthwise direction (rolling direction) of the plate thickness change steel plate such as the tapered plate or corrugated steel plate is visually or automatically sheared. It suffices that the detector of (1) has a length that can be identified as a cut portion, and 50 to 200 mm is sufficient.
As described above, the horizontal stepped portion for displaying the cut portion is formed by forming a plurality of areas of the same thickness change in the longitudinal end portions of the steel sheet with the changed thickness or within the same rolled steel sheet, and then cutting the plurality of sheets. In the case of a thickness-varying steel plate, if multiple different thicknesses are formed in the same rolled steel plate and then cut into a plurality of thickness-varying steel plates, multiple thickness changes in the same rolled steel plate When a steel plate is cut out, horizontal step portions are formed at the cut portions of the thickness difference connecting portions, in addition to the longitudinal end portions of the thickness-varying steel sheet as described above.

By forming the horizontal step portion for displaying the cutting portion in this manner, the starting point of the plate cutting (cutting) and the reference point are not unclear as described above, and accurate plate cutting can be performed. It is possible to obtain a target steel plate with a changed plate thickness with high accuracy.

Next, as described above, an example of forming the horizontal step portion for displaying the cut portion during rolling will be described. When rolling the rolled steel plate with the specified thickness such as product specified maximum thickness, product specified minimum thickness, product specified length etc. Plate thickness change with the same amount of reduction for a certain period of time A horizontal step for indicating the cutting portion is formed by rolling on the tip of the steel plate, and then specifications such as product specified maximum thickness, product specified minimum thickness, and product specified length are specified as above. Based on the above, the reduction amount of the upper and lower work rolls is changed with time (the time change of the reduction amount of the upper and lower work rolls may be the same or different), and after rolling the steel sheet, the reduction amount of the upper and lower work rolls is the same for a predetermined time. Then, a horizontal step portion for displaying the cut portion is formed at the rear end portion of the steel sheet with the changed thickness. When a plurality of different thickness rollings are performed in the same rolled steel sheet and then cut into a plurality of steel sheets of varying thickness, the cut portion is provided with the horizontal step portion for indicating the cut portion as described above. Is.

[0013]

EXAMPLES Next, examples of the present invention will be described. Example 1 In FIG. 1, a horizontal stepped portion 3 for displaying a cutting portion is formed by rolling at a tip portion of a taper plate 1 as a steel plate having a changed thickness, and after rolling into a taper shape, a rear end portion for displaying a cutting portion is similarly formed. The horizontal step portion 3a is formed by rolling. After rolling the taper plate 1 in this manner, the contact between the horizontal step portions 3 and 3a and the taper portion is cut and cut by an automatic shearing machine or gas cutting by a human hand to obtain a product.

Example 2 In FIG. 2, a horizontal stepped portion 3 for indicating a cutting portion is formed by rolling on a tip portion of a corrugated steel sheet 2 as a steel sheet having a changed thickness, then rolled into a corrugated shape, and then cut on a rear end portion. Horizontal step 3a for display
Is rolled and then cut and cut as described above.

Embodiment 3 In FIG. 3, a tapered plate 1 is used as a steel plate with a variable thickness.
A horizontal stepped portion 3 for displaying the cut portion is formed by rolling at the tip of the
Next, in the same rolled steel plate 1, as shown in the figure, a plurality of plate thickness change regions are tapered (plate thickness change steel plates) 1, 1a, 1
b and 1c are formed by rolling, horizontal step portions 3b, 3c and 3d for displaying the cut portion are formed by rolling at the respective taper (steel thickness changing steel plates) 1, 1a, 1b, 1c connection portions, and then at the rear end portion. After the horizontal step portions 3a for displaying the cut portions are formed by rolling, the horizontal step portions 3, 3a, 3b, 3 for displaying the respective cut portions are formed.
The contact points of c and 3d and the taper portion are cut off to cut out a plurality of steel plates 1, 1a, 1b, 1c of varying thickness.

[0016]

EFFECTS OF THE INVENTION According to the present invention, the starting point and the reference point of the cutting out (cutting) of the steel sheet with the changed thickness can be clarified, and the measurement of the thickness profile of the steel sheet with the changed thickness can be omitted. It is possible to improve efficiency and productivity. In addition, since it is possible to accurately identify the position in the longitudinal direction at which the actual plate thickness, etc., with respect to the target plate thickness, etc. can be accurately managed, it is possible to learn between steel billets and passes (rolling), so high accuracy is achieved. Can be managed and the quality can be improved. In addition, the contact points of each steel plate of the tie steel plate that rolls multiple product thickness-varying steel plates within the same rolled steel plate are clarified, and the tie design within the same rolled steel plate can be accurately performed, so automatic cutting (shearing) is performed.
With this, it is possible to obtain an excellent effect such that accurate sizing can be performed and productivity can be remarkably improved.

[Brief description of drawings]

FIG. 1 is a side view showing an embodiment of the present invention.

FIG. 2 is a side view showing an embodiment of the present invention.

FIG. 3 is a side view showing an embodiment of the present invention.

FIG. 4 is a side view showing a rolled state of a steel plate with a changed plate thickness.

FIG. 5 is a side view showing a rolled state of a steel sheet having a changed plate thickness.

FIG. 6 is a side view showing a rolled state of a steel plate with a changed plate thickness.

FIG. 7 is a side view showing a rolled state of a steel sheet having a changed thickness.

FIG. 8 is a side view showing a rolled state of a steel plate having a changed plate thickness.

[Explanation of symbols]

 1 Plate Thickness Change Steel Plate 1a Plate Thickness Change Steel Plate 1b Plate Thickness Change Steel Plate 1c Plate Thickness Change Steel Plate 2 Plate Thickness Change Steel Plate 3 Horizontal step for cutting part display 3a Horizontal step for cutting part display 3b Horizontal for cutting part display Stepped portion 3c Horizontal stepped portion for cutting portion display 3d Horizontal stepped portion for cutting portion display

Claims (2)

[Claims] 1. A plate thickness changing steel plate having horizontal step portions for displaying the cutting portion in the longitudinal direction, wherein horizontal step portions for displaying the cutting portion are formed by rolling at both ends in the longitudinal direction of the plate thickness changing steel sheet. . 2. A plurality of plate thickness change regions are formed by rolling in the same rolled steel plate in the longitudinal direction of the plate thickness change steel plate, and horizontal step portions for displaying cut portions are formed by rolling at the plate thickness change region forming connection portions, respectively. A steel plate with a variable thickness, which has a horizontal step portion for displaying a cut portion in the longitudinal direction, which is characterized by being squeezed.