JPS5819361B2 - Manufacturing method of rough shaped steel billet - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention mainly relates to a method for producing rough shaped steel pieces for shaped steel such as H-shaped or T-shaped steel and steel sheet piles.

As is well known, in order to manufacture H-shaped steel, ■-shaped steel, steel sheet piles, etc. by the rolling method, a square steel ingot is bloomed or slabbed with a square or rectangular cross section, or a rough shaped steel slab is rolled, and then roughened and finished. A rolling process was adopted, and a continuous casting process, in which blooms, slabs, or rough-shaped steel pieces were directly cast, was also adopted.

By the way, recently there has been an increase in demand for H-beam steel with a wide flange width and a large cross-sectional area, and the process of converting it into a rough-shaped steel billet, cooling it, and inserting it into a cold casing has an extremely large thermal loss. Since the method of hot rolling all at once from steel to finished product has been adopted, the following problems have arisen in the well-known method for producing rough-shaped steel billets.

(1) As shown in Fig. 1, the well-known production method by blooming rolling mainly performs web rolling of a rectangular steel ingot 1 in a horizontal mill consisting of an upper roll 2 and a lower roll 3. Roll as follows, and in the same way sequentially roll sets γ-3',
2" to 3" and 2"' to 3'" to form a rough-shaped steel piece d, but as is clear from Fig. 1, in this rolling method, there is no elongation in the width direction of the flange, so the flange width In order to obtain a large rough shape slab (ultimately a product), a thick steel ingot is required.

Therefore, in order to obtain the rough-shaped steel billet d from the steel ingot 1, the number of passes is increased, and the blooming ability is reduced.

In addition, when producing a bloom or slab with good blooming efficiency in the blooming process and obtaining a rough shaped steel slab in the rough rolling process, the rectangular steel slab 4 shown in Figure 4A (this may also be a rectangular steel ingot) is used. The width f of the flange-equivalent side surface 5 of the flange-equivalent side surface 5 of the rectangular steel piece (hereinafter simply referred to as a rectangular steel piece) must be larger than the flange width g of the rough-shaped steel piece 6 in Fig. 4 A, and the rough shape with a wide flange width To produce billets, thick billets must be heated.

Therefore, not only does the heating time in the heating furnace become longer, but the number of rolling passes also increases, resulting in a significant reduction in rolling efficiency.

(2) As mentioned above, when hot rolling is carried out from a steel ingot to a product without intermediate cooling, especially in the case of existing equipment, the above (1)
In addition to this, the process of forming rough shaped billets takes too much time, which tends to cause an imbalance in capacity between rough and finish rolling in the subsequent process, resulting in a problem that productivity does not improve.

(3) Making rough shaped steel pieces with wide flanges by continuous casting tends to cause mold thermal distortion and casting defects;
Also, problems remain, such as the fact that the flange part is likely to be insufficiently trained.

The purpose of the present invention is to provide an efficient method for manufacturing rough-shaped steel pieces without the above-mentioned problems. A plurality of pressing surfaces with different top angles of the central bulge are provided for each pair or group of roll pairs, and then the side surface corresponding to the flange of the rolled material having a square or rectangular cross section is pressed against the center of the central bulge. After rolling the material so that it aligns with the axis corresponding to the web center and spreading out the side surface corresponding to the flange, the side surface corresponding to the web is rolled down with a roll having a bulge whose top pressing surface is formed approximately parallel to the axis. It is characterized by a method for manufacturing rough shaped steel pieces for shaped steel.

The present invention will be explained in more detail below with reference to the drawings.

Now, in the case of H or ■-shaped steel, the rough shaped steel piece d obtained in Fig. 1 is roughly shaped by horizontal rolls in the order of caliber h and i, as shown in Fig. 2, and then subjected to a finishing rolling process (not shown). Sent.

Further, in the case of steel sheet piles or channel steel, as shown in FIG. 3, the rough shaped steel slab 6 is rolled into a caliber in the order of =s to produce a product.

The rough-shaped steel slabs obtained in the present invention are similarly subjected to a cooling process and then put into production, or are made into products by directly passing through a thermal opening and finishing rolling process without going through a cooling process. Any known technique can be adopted for the process after the rough shaped steel billet is formed.

As mentioned above, there are various problems with the well-known rolling technology in increasing the absolute length of the flange width after a rough-shaped steel billet is obtained. The flange widths t and u of the rolled steel pieces 7 and 8 at the time of rolling are the width 1 of the 5° side surface equivalent to the flange of the rectangular steel piece 4 and the rough shaped steel piece 6.
It is usually smaller than 17979 width g.

Therefore, the present inventors have researched a method for obtaining a rough shaped steel piece from the steel piece 4, for example, having a flange width larger in absolute value than the width f of the flange-equivalent side surface 5 of the rectangular steel piece 4, and as a result, the present invention method has been developed. As a result, it became possible to manufacture a section steel having a wide flange from a rolled material consisting of a steel ingot or billet with a thin rectangular or rectangular cross section. It is something that

For convenience of explanation of the present invention, the names of each part of the rolled material are defined as shown in FIGS. 5 and 6.

In FIGS. 5 and 6, the X axis passing through the center of the rolled material 9° 9' is called the web center corresponding axis, and the Y axis perpendicular to this is called the central axis.

Both side surfaces 10 and 10' parallel to the Y-axis are referred to as flange-equivalent side surfaces, and both side surfaces 11 and 11' parallel to the X-axis are referred to as web-equivalent side surfaces.

Now, the material to be rolled 9 is rolled by a pair of rolls 12, 1 shown in FIG.
2', the pair of rolls 12.12' has a central bulge 13.13', and grooves 14, 15.14', 15 symmetrically provided around the central bulge 13.13'. '
During rolling, the roll axis center 16 passing through the central bulge 13.13'
, 16' are made to coincide with the X-axis.

In FIG. 7, the pair of rolls 12 and 12' are shown separated for convenience of explanation, but both rolls 12 and 12'
It is rolled by simultaneous rolling, and the roll pair is 12.12'
may be a vertical roll or a horizontal roll.

Next, the details of the rolling procedure are shown in FIG. When the flange-equivalent side surface is pressed with the centers of
, 15.14', 15' are filled.

In this case, the longitudinal section of the central bulges 13, 13' parallel to the roll axis is a chevron shaped like an isosceles angle with slightly rounded apex and sides, as shown in the figure. In the case of 2α, it is better to be small at the initial suppression surface, and then it is preferable to increase it as the pass passes in the order of 0 in Fig. 8A. In other words, the rolled material 9 is When pressed, the side surface corresponding to the flange can be pushed down and expanded without any force.

In this case, the groove portion is, for example, 15a, is
It changes as shown in b.

The shapes and dimensions of the central bulge and groove according to the present invention are not limited to those described above, and can be designed within the scope of the present invention.

For example, the shape of the central bulge is semicircular when expressed in cross section.
It is possible to use the same type or a combination of suitable shapes such as a trapezoid, an equilateral triangle, and a rectangle, as long as they have rounded corners necessary for rolling.

The same goes for grooves, which should be designed according to the intended steel section.

Therefore, such suppression surfaces may be provided in the same role,
That is, the pressing surface as shown in the two mallows in FIG.
a, a pressing surface consisting of 15a and 14a', and 15a', central bulging parts 13b and 13b', and groove parts 14b, 15b and 14b'.

The method of the present invention may be carried out sequentially with a plurality of roll pairs, by providing a pressing surface consisting of 15b' together with a single roll pair, or by providing the same or different types of pressing surfaces for each single roll pair. good.

Furthermore, it is also possible to adopt a method in which a plurality of pairs of rolls each having a plurality of pressing surfaces are provided to manufacture many types of steel sections from many types of rolled materials.

In the present invention, a group of roll pairs is used to refer to the case where a plurality of pairs of rolls with different pressing surfaces are used, and the type and number of pressing surfaces are preferably designed according to the product type, rolling, and quality conditions.

Now, in the middle of the steps shown in Fig. 8 A, B, and A, the web-equivalent side surface 11.11' is pressed into a bulge whose top pressing surface is approximately parallel to the axis, that is, a compression corresponding to the inner web dimension. Although rolling may be performed using a roll having a surface, FIG. 9 shows an embodiment in which the rolling is applied from the two stages shown in FIG.

In Figure 9, 18°18' is the roll for web compression, and 19
．． 19' is the bulge, and 20.20' is the top suppression surface.

At this stage, the rolled material 9 becomes a assembled steel piece, and the flange part 2
1 web portion 22 is formed, and as is clear from FIG. 9, the width of the flange portion 21 is equal to the width of the flange-equivalent side surface 10.
It is significantly larger than 10'.

In this way, the present invention provides a rolled material having a thin rectangular or rectangular cross section (however, as is clear from the above description, the present invention does not necessarily require that it be geometrically accurate; The side surface may have a bulging or concave curved surface within a range that does not deviate from the purpose.

) provides an extremely efficient method for producing rough shaped steel slabs suitable for producing shaped steel sections with wide flanges, and is extremely useful in practice.

Therefore, the present invention can be applied to a process consisting of a well-known rolling mill train having a roughing mill followed by a blooming mill, and high efficiency can be obtained immediately.

In other words, it is extremely easy to roll the material to be rolled into a rectangular or rectangular cross-section with a blooming mill, and it is extremely difficult in terms of rolling balance to subsequently apply the method of the present invention to a rough-shaped steel billet using a rough horizontal mill. This is because it is advantageous, and the ability to easily produce rough-shaped steel pieces with different dimensions from the same square or rectangular steel piece is also extremely advantageous in terms of rolling schedules, making it possible to improve productivity.

Furthermore, when a reheating process is adopted, that is, when a rolled material with a rectangular cross section that has undergone a cooling treatment process is used, a thinner material can be used, making reheating easier and improving efficiency.

[Brief explanation of the drawing]

Fig. 1 is a schematic explanatory diagram of a rolling method using a well-known web rolling method, Fig. 2 is an explanatory diagram of a roll caliber after a well-known rough shaped steel billet, and Fig. 3 is an explanatory diagram of a caliber showing a well-known channel steel rolling procedure. , Figure 4 A, B, T. The work is based on the well-known dimensional comparison diagram of rolled material and rough shaped steel billet, No. 5.
Figure 6 is an explanatory diagram of the names of each part according to the present invention, Figure 7 is an explanatory diagram of the rolling procedure according to the present invention, and Figures 8A, B, and A are explanatory diagrams of the rolling procedure of the side surface corresponding to the flange according to the present invention, 9th
The figure is an explanatory diagram of a web-equivalent side rolling procedure according to the present invention. 1... Steel ingot, 2... Upper roll, 3...
...Lower roll, 4...Rectangular steel piece, 5...
... Flange equivalent side surface, 6 ... Rough shaped steel piece, 7
, 8... Rolled piece of steel, 9, 9'... Rolled material, 12.12'... Roll, 13.13
'...Central bulge, 14.14', 15.15
'...Groove, 16, 16'...Roll axis, 17, 17'...Axis, 18, 1
8'... Roll for web reduction, 19.19'.
...Bulging portion, 20.20'... Top pressing surface, 21... Flange portion, 22... Web portion.

Claims (1)

[Claims] 1. For a pair of rolls or a group of roll pairs each having a pressing surface consisting of grooves symmetrical about the central bulging portion, a plurality of pressing surfaces having different top angles of the central bulging portion are provided, and then a square or rectangular cross-section covering is provided. The flange-equivalent side surface of the rolled material is rolled with the center of the central bulge aligned with the web center-corresponding axis of the rolled material, and after the flange-equivalent side surface is spread out, the top suppression surface is made substantially parallel to the axis. A method for producing a roughly shaped steel piece for a shaped steel, the method comprising rolling down a side surface corresponding to a web with a roll having a formed bulge.