JPH0142762B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for rolling channel steel and an edger roll used in the method.

Using a universal mill (hereinafter referred to as U mill), in which the roll axes of the horizontal roll and vertical roll are orthogonally arranged, and which is usually used for rolling H-section steel, etc.
When attempting to hot-roll shaped steel, especially channel steel and similar shaped steel, the rolling free surface of the rolled material bulges out due to overfilling in the gaps between horizontal and vertical rolls, causing burrs. This burr is temporarily crushed and deformed in the next pass of the etching mill (hereinafter referred to as the E-mill), but is restored and generated again in the next pass of the U-mill.

When continuous reverse rolling is performed using these U mills and E mills as rough rolling mills, the above burrs are generated - deformation -
After repeated restoration and continuous reverse rolling,
When the final finish is applied through a finishing U mill (hereinafter referred to as U _F ), the rolled shape often has flanges f protruding from the outer surface of both ends of the web w, as shown in Figure 1 a, for example. p remains, and for this conventionally, it has been necessary to carry out plastic removal as shown by the imaginary line l in Figure 1a, and the effort and yield loss involved cannot be overlooked under the current demands for rationalized operations. be.

The rolling mill rows of the above U-E and U _F are illustrated in Fig. 2, where 1 is a soaking furnace, 2 is a blooming mill, 3 is a heating furnace, 4 is a breakdown rolling mill, and 5 is a roughing U mill. ,
6 is an E mill, 7 is a finishing U mill, and the channel steel hot rolled by such equipment is
Or the flange f as shown by the chain line C in Figure 1b.
This is because they are widely used in structures as square steel pipes that are assembled by welding facing each other.

(Conventional technology) When hot rolling channel steel, the conventional method of groove rolling has many restrictions in terms of the number of grooves and the depth of the grooves, especially in the case of large cross sections. Commercialization was extremely difficult, but in recent years the UE and
Using a rolling mill row of _U It has not been possible to advantageously produce a channel steel with a large cross section by performing reverse rolling multiple times in continuous rolling with E mill 6 and E mill 6.

However, according to the conventional work procedure for H-beam steel, the burr p' due to overfilling in the gap 10 between the horizontal rolls 8, 8' and the vertical rolls 9, 9' of the rough U mill 5 shown in FIG. As mentioned above, it is inevitable that a protrusion P as shown in FIG. 1a will appear in the product channel steel due to this.

In other words, as shown in Fig. 3b, a slight protrusion p is allowed as it is unavoidable, but the burr p' is removed to prevent it from becoming a bending flaw, that is, a defect due to the burr p' wrapping. Relief groove 1 corresponding to
Etching rolling was carried out using an E mill 6 using a receiving roll 12 with a flange f and a push roll 12' for forming the end of the flange f, so that the rolled product was left with an overhang p shown in Fig. 1a. It becomes a channel steel shape. And when using it, protruding p
They had no choice but to take the disadvantageous method of making the outer corners of the channel steel square by additional processing such as shaping and removing.

As shown in FIG. 4a, as another E-mill 6, it may be considered to use a receiving roll 14 having a roll slope 13 for crushing the burr p', and to carry out an edging rolling that suppresses the burr p'. However, even with this method, it is difficult to eliminate fold-in flaws, and at this time, by crushing the burr p', bulges 15 and 16 protrude in the adjacent areas on both sides of the burr, and the subsequent U mill process At the pass, bulge 1 as shown in Figure 4 b
5 and 16 are extruded again toward the gap 10 between the horizontal and vertical rolls 8, 8', 9, and 9', and the burr p' is likely to be restored and generated again, so that it is difficult to expect that it will be effective.

(Problems to be Solved by the Invention) The above-mentioned phenomenon can be solved simply by reverse rolling in the rough U mill 5-E mill 6, using rolls with almost the same shape as the upper and lower rolls of the E mill 6. If only the cumulative reduction in the downward direction is added, the deformation of the burr p' in the U mill 5 will simply be repeated every time reverse rolling is performed, and it is generally difficult to eliminate the protrusion p in the product. However, the protrusion P had to be kept at best to prevent it from becoming a fold-in flaw.

Therefore, the present invention has newly developed a set of left and right stepped rolls that can make the width of the roll hole type groove variable with respect to the E-mill 6 for rolling such channel steel. The purpose of this invention is to enable continuous reverse rolling of channel steel products without protrusion P as shown in FIG. 1b using the same edger roll even when the channel steel products are of different sizes.

(Means for Solving the Problems) The inventors believe that the widening of the material during edge rolling with an E mill, especially the bulges 15 and 16 as represented in FIG. During reverse rolling, both horizontal and vertical rolls 8, 8',
9 and 9' due to being located too close to each other on both sides of the gap 10. The deformation is carried away to the side, dispersed, and even to the extent that it can be erased by rolling on the roll faces of both the horizontal and vertical rolls of the U mill, thereby converting it into a stretching deformation in the U mill. It has been found through Amata rolling experiments that if the burr p' is allowed to regenerate, the disadvantage that the burr p' will not be generated again is unlikely to occur.

That is, in this invention, a rough material for channel steel is continuously reverse rolled in a rough universal mill and an edge mill, and then passed through a finishing universal mill to form a final channel shape having a web and flanges on both sides. In rolling the channel steel, the edge mill is equipped with a push roll that forms the flange end in contact with the inner surface of the flange portion, corresponding to the cross-sectional shape of the rolled material that has passed through the rough universal mill. The receiving roll for this is provided with an inside corner portion facing the outer surface area of each corner portion on both sides of the cross section of the material to be rolled, and a right and left side is provided with an adjustable distance between the facing surfaces of these inside corner portions. Using a set of corrugated rolls as an upper and lower pair, constraint rolling is performed on the outer surface area of the cross-sectional corner portion of the material to be rolled by the inside corner portion of the corrugated roll for each rolling unit pass or multiple passes of the reverse rolling, The process is repeated under the above-mentioned adjustment of the roll gap and inter-face distance to remove burrs caused by overfilling that appear during rolling with a rough universal mill at the cross-sectional corner of the material to be rolled, from the corner to the flange. A method of rolling channel steel characterized by rolling a bulge distributed toward the center of the web and toward the center of the width of the web. In the edge mill, which is responsible for forming the flange end of the rolled material that passes through the rough universal mill and forms a groove, the receiving roll that contacts the outer surface side of the web part of the rolled material has a cross section of the rolled material. It is characterized by a set of left and right stepped rolls each having an inside corner facing the outer surface area of each corner on both sides, and the distance between the facing surfaces of these inside corners can be expanded or contracted. This is an edger roll for rolling channel steel.

(Function) During rolling, E Mill 6, which was used for reverse rough rolling in the conventional U-E and U _F rolling mill rows, changed the groove shape determined by the turning process of the rolls. However, the degree of crushing deformation of the burr p' generated during rolling by the U mill 5 was only slightly adjusted by adjusting the upper and lower coal gaps. So,
Among the upper and lower pairs of rolls of the E mill, the receiving roll that faces the outer surface of the web w, as opposed to the push roll that faces the flange edge of the material to be rolled,
As shown in FIG. 5a, the stepped rolls 17 and 17' are divided into a pair of left and right parts, each with an inner corner part 19 facing the outer surface area of each corner part on both sides of the cross section of the material to be rolled. , 19', and the distance b between the facing surfaces of these inside corner portions 19, 19' can be adjusted.In this way, the roll hole type of the E mill 6 is similar to that of the U mill shown in FIG. 3a. 5
The size of the burr p' generated in accordance with the degree of overfill determined by the vertical rolling by the horizontal rolls 8, 8' and the horizontal rolling by the vertical rolls 9, 9' is determined. It is possible to appropriately set the roll gap g and the distance b between the inner corner portions 17 and 17' of the left and right receiving rolls.

By changing and adjusting these settings, the burr p' generated during the rolling pass of U mill 5 can be properly moved from the corners of both outer ends of the web part of the material to be rolled to the center of the width of the web part and the height of the flange part. Edging is performed so that the bulges are dispersed and separated as much as possible toward the center, for example, as shown at 15' and 16' in FIG. 5a.

The bulges 15' and 16' that are moved away from the corners during this etching are the bulges 15' generated in the immediate vicinity of the corner parts rolled down by the conventional receiving roll 14 with an inclined surface shown in FIG. 4A. , 16 have completely different properties.

In other words, the problem is that the bulges 15 and 16 sometimes become folding defects due to repeated deformation which immediately restores the burr p' as explained with reference to FIG. 4b during rolling in the next pass U mill 5. However, the bulges 15' and 16' generated in the E mill 6 according to the present invention are caused by the horizontal rolls 8 and 16', as shown in FIG. 5b, during the next pass rolling in the U mill 5.
8' and the gap 10 between the vertical rolls 9 and 9', the width does not return and the stretching occurs in the rolling direction.

That is, the bulge in the previous E mill pass is 15', 1
There is no possibility that the burr 6' returns to the burr point again, and the etching rolling by the E mill can be performed effectively.

(Example) Next, an example of the present invention will be described with U-E and U _F in Fig. 2.
A description will be given below of the case in which this method is applied to the manufacture of large channel steel using a rolling mill train.

Continuously cast slabs, large cross-section blooms or agglomerates are heated and soaked to 1200°C to 1300°C in a soaking furnace 1, and then, in a blooming mill 2, they are turned into so-called rough-shaped steel slabs 37 as shown in FIG. 6a. Slabs of similar cross section obtained by blooming rolling or continuous casting are subjected to groove rolling under soaking to form a vertically asymmetric rough groove cross section 38 as shown in Figure b, and then After being reheated in the heating furnace 3, the groove rolling is performed in the breakdown rolling mill 4 to sequentially shape the groove cross section to 39 and 40 as shown in Fig. 7a and b to obtain a coarse material for groove steel. Processed into.

Next, it is sent to a rough U mill 5 and an E mill 6, and by combination rolling in both mills, the rough material 40 for channel steel shown by the broken line in FIG. During this process, the roll gap is sequentially reduced and continuous reverse rolling is performed multiple times.

Finally, it is finished into a predetermined size and shape using a finishing U mill 7.

Here, in the continuous reverse rolling process, the E mill 6, as already mentioned, the horizontal roll 8 of the rough U mill 5,
8' and vertical rolls 9, 9' under pressure in Figure 3a.
It is necessary to appropriately set the roll gap g and inter-plane distance b as shown in FIG.

Regarding the setting of the inter-face distance b, for example, the step rolls 17 and 17' are moved in the axial direction by electrical control that follows the movement of the vertical rolls 9 and 9' in the rough U mill 5, and the steps are An example of a mechanism suitable for adjusting the distance b between the facing surfaces of the entry corner portions 19 and 19' of the rolls 17 and 17' is shown in the ninth section.
As shown in the figure.

In this example, a conventional push roll 12' serving as the upper roll can be used as is, and is used as a drive roll as is customary.

In this example, the receiving roll as the lower roll is in contact with the outer surface of the groove-shaped web part of the rolled material and the roll cylinder 18,1 which is in contact with the outer surface of the flange part.
It consists of a pair of left and right stepped rolls 17, 17' having flanges rising from 8', and there is no need to drive the rolls; for example, as shown in the figure, the stepped rolls 17, 17' It can be of a non-driven type that follows and rotates in accordance with the progress of the rolled material driven by the pusher roll 12' via the tapered roller bearing 20. The above-mentioned collars of the stepped rolls 17, 17' form respective inside corner portions 19, 19' facing the outer surface area of each corner portion on both sides of the cross section of the rolled material shown in the figure. Then, the distance b (fifth
(see Figure a), the rotation of the control motor is controlled by the worm 21, the worm gear 22, although not shown.
This threaded sleeve 23 houses a fixing box 24 with a female thread on the inner periphery in place of a normal roll chock, and houses it in a housing 25, and receives the thrust with a keeper plate 26 so that the axis of the fixing box 24 is fixed. By fixing the directional movement, the movement of the stepped rolls 17, 17' is carried out in conjunction with the forward or backward movement in the roll axis direction accompanied by the rotation of the threaded sleeve 23.

In the figure, 27 is a two-split connecting ring, 28 is a sliding sleeve, 29 is a mandrel, and 36 is a bracket that supports the center of the mandrel 29.

The outer dimensions and shape of the fixing box 24 are the same as those of the conventional E-mill chock, so the stepped roll 1
7, 17' can be moved in the vertical direction using a screw 30 for rolling up in the same manner as in normal H-section steel rolling.

By applying the stepped rolls 17, 17' to the E mill, effective forming can be performed under restraint rolling on the protruding corners of the channel steel, as shown in Fig. 1a.
The protrusion P shown in Figure 2 can be eliminated, and the protruding corner shape can be neatly shaped as shown in Figure b. For example, as shown in the figure, the outer angle of the joint between the web W and the flange F can be uniformly shaped with a right angle and a small radius. It became easier to do.

Moreover, such a shaping effect does not directly affect the size of the material to be rolled, and it is possible to roll several types of products with different thicknesses using the same stepped roll. Further, by changing only the push roll 12', the present invention can be applied to rolling different types of channel steel.

Although the E mill 6 in the above example is explained in the case where it is driven on one side, the same effect can be obtained even if both the upper and lower rolls are not driven, such as in the U-EU-U and U- _F rolling mill arrangement. is obtained.

In FIG. 10, the receiving rolls of the E mill, that is, a set of left and right stepped rolls 17, 17' are connected to the spry shaft 31.
An example is shown in which the slider 34 having a pair of rollers 33 that pinches the flanges of the stepped rolls 17 and 17' is moved by the rotation of the right and left counter threaded spindles 32. A fixed position on the spline shaft 31 can be set. In the figure, 35 is a rotation stopper guide rod. By driving this spline shaft 31, both the upper and lower rolls of the E mill 6 can be driven.

(Effect of the invention) As described above, according to this invention, U-E and
When rolling a channel-shaped material using a rolling mill row system consisting of U- _F , there is a problem with the bulging burrs that occur on the rolling free surface in the roll gaps where rolling is not achieved during the rolling of the rough U mill in the previous stage during U-E continuous rolling. Constrained rolling is performed in the E mill, and the bulging burr is transferred to the range that can be rolled in the next U rolling, so that each rolling unit pass or multiple passes of reverse rolling through both the rough U and E mills are carried out.
By adjusting the interval between the stepped rolls of the E mill and rolling the material away from the corner areas of the material to be rolled in the form of a dispersed bulge, the next pass in the rough U mill will be turned into longitudinal stretching. As a result, a beautiful channel steel finish with no protrusions can be obtained.

Moreover, the etching rolling by this E mill can be advantageously carried out.

[Brief explanation of drawings]

Figure 1a is a cross-sectional view showing the product shape of a channel steel produced by a conventional rolling mill train consisting of U-E and _UF , and Figure 1b is a channel steel obtained by the present invention and its assembly into a square steel tube. The cross-sectional view when combined, Figure 2 is U-E.
A layout diagram of a rolling mill row consisting of U _F , Fig. 3a and b is a front view of the main parts of each roll, showing a cross section of the rolled material in the conventional U mill and E mill rolling processes, Fig. 4 a , b are partial front views of the E mill and U mill rolls illustrating the conventional method of crushing extrusion and its restoration, and FIG. Fig. 6b is a front view of the main part of the roll of the U mill showing how the protrusion is stretched in the longitudinal direction; Figs. Figures a and b are cross-sectional views of the breakdown rolled shape, Figure 8 is a diagram showing the relationship between the rough material and the rough U mill roll gap, and Figures 9 and 10 are each section of the E mill according to the present invention. It is a partial sectional view showing an example. 5... Roughing universal mill (U mill), 6... Edge mill (E mill), 7... Finishing universal mill (U _F mill), w... web, f... flange, g... roll gap, b... inside corner Distance between facing surfaces at the corner, p'...burr due to overfilling, 1
2'...Press roll, 15', 16'...Bulge, 17,
17'...Stepped roll, 19,19'...Inner corner portion.

Claims (1)

[Claims] 1. A rough material for channel steel is processed by a rough universal mill U.
In rolling the channel steel, it is subjected to continuous reverse rolling with Etsuya Mill E and then passed through finishing universal mill U _F to finish it into a final channel shape having a web w and flanges f on both sides. A push roll 12' that forms a flange end in contact with the inner surface of the flange part corresponding to the cross-sectional shape of the material to be rolled that has passed through the rough universal mill U, and a receiving roll for this. are the inside corner portions 19, 19' facing the outer surface area of each corner portion on both sides of the cross section of the rolled material.
A pair of left and right stepped rolls 17, 17' are used as an upper and lower pair, and the distance b between the facing surfaces of these inside corner portions 19, 19' can be adjusted. The restraint rolling of the outer surface area of the cross-sectional corner portion of the material to be rolled by the inside corner portions 19, 19' of 17' is carried out by the roll gap g for each rolling unit pass or multiple passes of the reverse rolling.
The rough universal mill U is applied at the corner of the cross section of the material to be rolled.
The feature is that the burr p' caused by overfilling that appears due to rolling is kept away from the corner part as bulges 15' and 16' distributed toward the center of the height of the flange part and the center of the width of the web. A method of rolling channel steel. 2. In the Edger Mill E, which consists of an upper and lower pair of push rolls 12' and receiving rolls with an adjustable roll gap g, and is responsible for forming the flange end of the rolled material that passes through the rough universal mill U and forms a groove, The receiving roll that is in contact with the outer surface side of the web portion of the material to be rolled faces the outer surface area of each corner portion on both sides of the cross section of the material to be rolled, and has an inner corner portion 19,
19', and these inside corner parts 19,1
An edger roll for rolling channel steel, characterized in that it consists of a pair of left and right stepped rolls 17, 17', in which the distance b between mutually facing surfaces of 9' can be expanded or contracted.