JP2001137944A - Angle steel straightening roll - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a straightening roll having an uniform feed speed in simultaneously straightening plural angle steels. SOLUTION: Relating to a pair of straightening rolls having a ruggedness part conformable with a shape of an angle steel to be straightened, angle steel straightening rolls are constituted so that at least one of the straightening roll is a drive roll, a surface of a straightening roll as the drive roll and a mountain top part of the angle steel are brought into contact with each other but the surface of the straightening roll as the drive roll and foot tip parts of the angle steel are not brought into contact with each other. Further, the straightening roll, in which a depth of a recessed part of the straightening roll is shallower than a height of the angle steel to be straightened, is used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a straightening machine for straightening angle iron. In particular, the present invention relates to a straightening machine of a multi-section steel in-line straightening system for simultaneously conveying and straightening a large number of angle irons.

[0002]

2. Description of the Related Art Japanese Patent Application Laid-Open Nos. 62-120912 and 8-168919 disclose rolling, cooling, straightening,
A cutting system is disclosed. As disclosed in these, the bar steel rolled in the rolling mill is generally several tens of meters to several hundreds of meters in length, but is suitable for the cooling floor length in order to flow to the next cooling step. And cooled by a cooling floor. After that, thermal stress distortion occurs due to uneven cooling in the cooling floor.Therefore, it is necessary to perform a process of removing distortion such as bending by a straightening machine and to cut the product length, and these may be performed offline, but cooling in the cooling floor may be performed. After that, the mainstream is a method of straightening the product downstream and cutting it into a product length. At this time, it is necessary to match the rolling capacity with the equipment capacity below the cooling floor, but the straightening speed is slower than the rolling speed. Are adopted. When straightening a plurality of strips at a time in this way, use the upper and lower rolls having grooves according to the number and shape of the strips as the rolls of the straightening machine, while rolling down a plurality of these upper and lower rolls alternately. Straightening is performed by a multi-roll straightening machine to be passed. The multi-strip group sent out from the straightening machine by a predetermined length is simultaneously cut by the cutting machine to be a product.

[0003]

In the case of multi-section straightening / cutting as described above, a difference in feed speed occurs due to a subtle difference in shape of each bar, resulting in a variation in product length. Problem. This is because if the bite height on the straightening roll changes depending on each bar due to a subtle difference in shape, there will be a difference in the turning radius of each bar, so there will be a difference in feed speed, and a large number of bars will be cut at the same time. Then, the difference in feed speed appears as a variation in product length.

FIG. 5 shows a conventional angle steel straightening roll. When straightening the angle iron 3, it is general to perform straightening by combining a roll having an angled convex portion and a roll having a concave portion which is a V-shaped groove portion. Here, a roll having a concave portion is referred to as an upper roll 1, and a roll having a convex portion is referred to as a lower roll 2. In addition, the angle iron height is set to 6, and the groove depth of the concave portion is set to 7. Normally, the apex angle of the V-shaped concave portion of the upper roll 1 and the apex angle of the angled convex portion of the lower roll 2 are also set to 90 °, but the shapes of the plurality of angle irons 3 fed simultaneously are slightly different. And the apex angle deviates from 90 °, respectively, within the JIS tolerance range. As shown in FIG. 6, when the central portion of the cross section of the angle iron 3 is referred to as a peak portion 4 and the end portion is referred to as a forehead portion 5, if the angle of the angle iron 3 is smaller than 90 °, it can be understood from FIG. 5. As shown, the peak 4 of the angle iron 3 first strikes the upper roll 1,
When the apex angle of the angle iron 3 is greater than 90 °, the leg portion 5 comes into contact with the upper roll 1 first. In the case where the upper roll 1 is a driving roll, when the position of each angle iron is shifted in the radial direction of the roll, the apex angle of the angle iron 3 becomes 90 °.
When it is larger, the turning radius with respect to the upper roll 1 becomes larger and the feed speed becomes faster than when the apex angle of the angle iron 3 is smaller than 90 °. In this way, although the difference is slight, the feed speed varies among the angle irons, and as a result, the lengths of products cut at the same time thereafter vary.

[0005] It is an object of the present invention to solve the above-mentioned problems and to provide a straightening roll having a uniform feed rate when straightening a plurality of angle irons at once.

[0006]

The above object can be attained by the following invention in which the shape of an angle steel straightening roll having an uneven portion is changed.

The first invention of the present invention is directed to a set of straightening rolls having an uneven portion corresponding to the shape of an angle steel to be straightened, wherein at least one of the straightening rolls is a driving roll and the straightening roll is the driving roll. The angle iron straightening roll is characterized in that the surface of the angle iron comes into contact with the peak of the angle iron, but the surface of the straightening roll, which is the driving roll, does not contact the leg of the angle iron. The second invention of the present invention is the angle steel straightening roll according to the first invention, wherein in the straightening roll, the depth of the concave portion of the straightening roll is shallower than the height of the angle steel to be straightened. In the third invention,
The angle steel straightening roll according to the first invention or the second invention, wherein the uneven portion has a plurality of portions.

[0008] As described in the problem to be solved by the invention, when the angle of the angle iron is greater than 90 °, only the leg portion comes into contact with the roll, and the radius of rotation with respect to the roll changes. Therefore, by cutting the roll where the leg of the angle iron comes into contact, creating a gap between the roll and the leg, so that the leg does not contact the roll, the angle iron is always straightened at the peak. It comes into contact with the roll and the deviation of the radius of rotation is suppressed. FIG. 1 shows an example in which a roll having a convex portion is processed so that the leg portion of the angle iron 3 does not contact the roll. Due to the existence of the gap 8, the angle iron 3 is in contact with the lower roll 2 having a convex portion only at the peak. Similarly, in the case of a roll having a concave portion that is a V-shaped groove, the upper part of the roll groove (near the roll surface) is similarly cut off, and a conventional roll is processed so that the leg of the angle iron does not contact the roll. However, as shown in FIG. 2, the above problem can be solved very effectively by using a straightening roll in which the depth of the groove of the concave portion of the roll having the concave portion is shallower than the height of the angle iron. If such a roll is used, the contact of the leg portion with the roll is completely eliminated, and a roll having a small roll diameter may be used. It is particularly effective to use a straightening roll in which the depth of the groove is 66% or less of the height of the angle iron. It is effective if the portion where the leg of the angle iron comes into contact with the roll is reduced as much as possible. However, if the depth of the groove is 66% or less of the height of the angle iron, variation in the product length can be sufficiently reduced. .

The fact that the roll diameter can be reduced means that the cost of the roll itself and the workability at the time of replacing the roll are increased. From this viewpoint, the straightening roll of the present invention is effective not only in the case of multiple strips, but also in a straightening machine that performs single straightening, that is, a single straightening machine.

The above-described change of the roll shape is effective if at least the drive roll is changed. When both of the set of rolls having the concave and convex portions are drive rolls, the present invention may be applied to one or both of them. The present invention may be applied to a roll other than a driving roll.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The angle steel straightening roll of the present invention is used as a driving roll of a straightening machine roll. FIG. 1 shows an embodiment in which the lower roll 2 having a convex portion is a drive roll. FIG. 2 shows an embodiment in which the upper roll 1 having a concave portion is a drive roll. When only the upper roll 1 and the lower roll 2 are drive rolls, the present invention may be applied to each of them. In the case of driving the upper and lower rolls, the effect is obtained by using the present invention for either one of the rolls. However, the present invention is more effective when the present invention is used for both the upper and lower rolls. An embodiment in this case is shown in FIG. The angle steel that has been conveyed and straightened between the straightening rolls using the present invention is cut into a predetermined size using various shears or the like, and becomes a product.

When the straightening roller presses only the vicinity of the peak of the angle iron in this way, scale peeling occurs only in the pressed portion, and the surface looks uneven, but this is not a problem in practical use. When the unevenness of the surface is a problem, the contact ratio between the angle steel and the straightening roll is increased, or the depth of the groove is made closer to the height of the angle iron, so that it becomes less noticeable. Since the degree of the unevenness has a balance with the reduction force of the correction, the actual groove depth is appropriately adjusted according to the operating conditions.

Although a normal multi-stage straightening machine has a plurality of straightening rolls above and below, it is not necessary to use the present invention for all straightening rolls. However, when the present invention is applied to a roll having a large reduction (correction load) among the straightening rolls, the effect is particularly large. The greater the number of straightening rolls of the present invention, the higher the effect. Of course, the present invention may be used for all straightening rolls because of the effect of reducing the weight of the rolls.

[0014]

The present invention will be specifically described below based on examples and comparative examples.

[Example 1] In an in-line straightening and cutting system for straightening a plurality of bar steels conveyed from a cooling floor at the same time and cutting continuously after straightening, a 7-row angle steel (one piece of about 1
21m) was simultaneously straightened and subsequently cut to a product length of 6m. There are eight straightening rolls, and as shown in FIG. 2, the groove depth of the upper roll 1 having a V-shaped groove recess is determined by the angle steel 3 to be straightened.
The upper roll 1 was formed so that the groove of the upper roll 1 was made shallow so as to be 66% of the height of the upper roll (the upper roll obtained by cutting the upper roll of a comparative example described later). The angle irons sent out from the straightening machine were measured, and were cut at the same time using a shear while running, thereby obtaining a product. The driving roll was the upper roll 1. The variation in product length after straightening / cutting was ± 4 mm. There was no problem with the correction. The unevenness in appearance of the product due to scale peeling at the contact portion of the upper roll was hardly noticeable. The weight of the roll was about 90% of the weight of the roll of the comparative example described later.

[Example 2] In an inline straightening and cutting system for straightening a plurality of steel bars conveyed from a cooling floor at the same time and cutting continuously after straightening, a seven-section angle iron (one piece of approximately 1
21m) was simultaneously straightened and subsequently cut to a product length of 6m. As shown in FIG. 4, the straightening roll has eight straightening rolls, and the groove depth of the upper roll 1 having the concave portion of the V-shaped groove is 50% of the height of the angle iron 3 to be straightened. With a shallow groove (the upper roll was shaved from a comparative example described later). The angle irons sent out from the straightening machine were measured, and were cut at the same time using a shear while running, thereby obtaining a product. The driving roll was the upper roll 1. The variation in product length after straightening / cutting was ± 4 mm. There was no problem with the correction. Although the appearance of the product may be uneven due to scale peeling at the contact portion of the upper roll, there was no practical problem. The weight of the roll was about 84% of the weight of the roll of Example 1.

[Comparative Example] In an in-line straightening and cutting system that straightens a plurality of bar steels conveyed from a cooling floor at the same time and cuts continuously after straightening, a 7-row angle iron (one piece of about 12
1m) was simultaneously straightened and subsequently cut to a product length of 6m. As shown in FIG. 5, the straightening roll has eight straightening rolls, and as shown in FIG. 5, the groove depth 7 of the upper roll 1 having the concave portion of the V-shaped groove is set to a depth that the height 6 of the angle iron to be straightened completely falls. A conventional product was used. Angle iron sent from the straightening machine is measured,
Using a shear, 7 pieces were cut at the same time while running to obtain a product.
The driving roll was the upper roll 1. The variation in product length after straightening / cutting was ± 8 mm.

As described above, when the straightening roll of the present invention in which the groove of the upper roll is substantially shallow was used, the variation in the product length became small, and the effect of the present invention was confirmed. Also, the straightening roll could be reduced in weight.

[0019]

According to the present invention, the variation of the conveying distance between the strips in the multi-row straightening can be reduced by a small change of the straightening roll, and a product having a uniform length can be obtained. In addition, since the straightening roll can be downsized, this alone can lead to cost reduction of the roll.However, at the same time, the weight reduction due to the downsizing makes it easy to replace the roll, improving workability. it can. Since the effect of downsizing the roll is applicable to the case of a single strip, the present invention can be widely applied to the straightening of angle irons including the case of straightening only one roll.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a cross-sectional shape of an angle steel straightening roll of the present invention.

FIG. 2 is an explanatory view showing a cross-sectional shape of an angle steel straightening roll of the present invention.

FIG. 3 is an explanatory view showing a cross-sectional shape of the angle steel straightening roll of the present invention.

FIG. 4 is an explanatory diagram showing a cross-sectional shape of the angle steel straightening roll of the present invention.

FIG. 5 is an explanatory view showing a cross-sectional shape of a conventional angle iron straightening roll.

FIG. 6 is an explanatory view of an angle iron.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Upper roll 2 Lower roll 3 Angle iron 4 Peak part 5 Leg part 6 Angle iron height 7 Groove depth 8 Clearance

Claims (3)

[Claims] 1. A set of straightening rolls having an uneven portion conforming to the shape of an angle steel to be straightened, wherein at least one of the straightening rolls is a drive roll, and a surface of the straightening roll being the drive roll. An angle steel straightening roll characterized in that the peak of the angle iron comes into contact, but the surface of the straightening roll, which is the driving roll, does not contact the leg of the angle iron. 2. The angle steel straightening roll according to claim 1, wherein a depth of a concave portion of the straightening roll is smaller than a height of the angle steel to be straightened. 3. The angle steel straightening roll according to claim 1, wherein the uneven portion has a plurality of portions.