JPH012704A - Universal rolling method for asymmetric section steel - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Application in the Cfl Industry The present invention relates to a universal rolling method for asymmetric sections such as channel steels with projections.

(Prior Art) A channel steel with projections shown in FIGS. 8(a) and 8(b) is generally used as a mast material for a forklift. This shaped copper has conventionally been produced by a hot extrusion method using a die, but recently there has been a shift to a production method using roll rolling.

An example of a manufacturing method using roll rolling is shown in FIGS. 9 to 13.

This method uses groove rolling using double rolls to form an asymmetrical intermediate rough-shaped steel piece in which the shoulder, which is the part facing the protrusion, is thinner than the shoulder shape of the product. (Fig. 9, Fig. 1θ) and a universal rolling process (11th
Fig.)', a groove rolling process (Fig. 12) to shape the length of the protrusion and flange, and a vertical roll to eliminate the gradient in the thickness of the protrusion and flange and to ensure that each part has the specified thickness. and a universal rolling process (Fig. 13) in which the horizontal rolls are in contact with each other and their relative positional relationship is constant.

FIG. 14 shows another example of the conventional method. In this method, the 14th
As shown in the figure, a process of manufacturing an asymmetric intermediate rough-shaped steel piece in which a roll draft angle is provided on the sides of the protrusion and flange by groove rolling, and a dummy protrusion is provided in the portion facing the navigation protrusion. and a step of rolling the excess thickness caused by the roll draft into a right-angled cross section by universal rolling in which the reduction is balanced by the dummy protrusion, and a hole shape that does not reduce the protrusion and flange in the thickness direction. It consists of a process of shaping and rolling to product dimensions by rolling. (JP-A-60-145201 size%
I) (Problems to be Solved by the Invention) However, in these methods, in universal rolling in which an intermediate rough-shaped steel piece is rolled, the web part is in a substantially horizontal state, so the upper roll is used to roll the web part. There is an upward reaction force due to this, and a rightward reaction force (thrust) due to rolling the protrusion. In general, rolling mills have high rigidity against reaction forces in the radial direction, but low rigidity against thrust. Therefore, the upper roll moves to the right, making it difficult to obtain a predetermined shape of the rolled material. Figure 11,
In the conventional method shown in Fig. 14, as a countermeasure, the upper horizontal roll and the right vertical roll are brought into contact with each other, thereby replacing the thrust acting on the upper horizontal roll with the reaction force in the radial direction of the right vertical roll, and moving the upper horizontal roll to the right. is dealing with the movement of

On the other hand, universal rolling generally has less bending and twisting of the rolled material than groove rolling because the stretching ratio of each part of the web, flange, and protrusion can be made the same, and it is easier to roll the rolled material perpendicular to each surface. It is desirable to perform multiple passes as much as possible, as there are advantages such as good surface quality and the ability to apply a large stretching ratio. However, the first
In conventional universal rolling shown in Figures 1 and 14, when multiple passes are performed, the upper horizontal roll and right vertical roll are in contact only in the final pass, and in the other passes, each roll is an open set. The upper horizontal roll and the right vertical roll do not touch. That is, the thrust acting on the upper horizontal roll causes the upper horizontal roll to shift to the right, and as is clear from the figure, the protrusion becomes thicker than the predetermined size. Furthermore, since the upper horizontal roll and the right vertical roll come into contact only in the final pass, the rolling reduction ratio of the protrusion is greater than that of other parts, causing bending and twisting of the rolled material.

The purpose of the present invention is to prevent the horizontal movement of horizontal rolls due to thrust in all passes of the universal rolling process of asymmetrical channel steel with protrusions, and to maintain the dimensions of the protrusions at a predetermined level.
Another objective is to eliminate bending and twisting of the rolled material during the final pass of universal rolling or the next rolling process.

(Means for Solving the Problems) The rolling method of the present invention for achieving this object is configured as follows. In other words, when manufacturing an asymmetrical section steel such as a channel steel with protrusions by rolling that includes a universal rolling process that performs multiple passes, a certain length is applied to the non-rolled surface of one of the upper and lower horizontal rolls and one of the left and right vertical rolls. This is a universal rolling method for asymmetric section steel, which is characterized in that a sloped portion having a slope is formed, and rolling is performed in a state in which both sloped portions are in contact and engaged during all rolling passes.

The present invention will be explained in detail below using the figures.

The rough/intermediate rolling process for obtaining intermediate rough-shaped steel pieces uses the same method as the conventional method shown in FIG. 9. FIG. 1 shows the roll groove shape at the final stage of groove rolling. 2nd to 4th
The figure shows the roll set for each pass when the same roll is used and the roll set is changed to perform three passes of universal rolling. The figure shows finish universal rolling.

An intermediate rough shaped steel piece is obtained through the rough and intermediate rolling steps shown in FIG. 9 and the step shown in FIG. Next, by the universal rolling process shown in FIG. 2, the web portion, both flanges, and projections of the rolled material are rolled. Here upper horizontal roll 1
The right vertical rolls 4 are in contact with each other at the inclined part "a". Therefore, the right vertical roll 4 prevents the upper horizontal roll 1 from moving to the right. That is, this inclined portion "a" has an angle α with respect to the horizontal roll axis and an angle β with respect to the vertical roll axis, so that the non-rolled surfaces of the horizontal roll 1 and the vertical roll 4 come into contact and engage with each other. ing.

That is, the upper horizontal roll 1 receives an upward reaction force due to rolling the web portion and a rightward reaction force due to rolling the protrusion. Therefore, the upper horizontal roll tends to move upward and to the right. On the other hand, although rolling mills have high rigidity in the radial direction and can easily adjust the roll set in the radial direction, they generally have low rigidity in the thrust direction and cannot easily adjust the roll set. Therefore, the upper horizontal roll 1 tries to move to the right.

However, since the upper horizontal roll 1 and the right vertical roll 4 are in contact with each other at the inclined part "a" in FIG. The protrusion can be rolled to a predetermined thickness.

Next, the rolled material is subjected to shaping rolling as shown in FIG. 5 to control the lengths of the flanges and protrusions. Thereafter, each part of the rolled material is rolled down again by the universal rolling shown in FIG. At this time, as in the case of FIG. 2, the lower horizontal roll 1 and the right vertical roll 4 are in contact at the inclined part "a", and the upper horizontal roll 1 is prevented from moving to the right. It is important here that the upper and lower horizontal rolls 1.2 are set in positions that are moved upward relative to the left and right vertical rolls 3.4 compared to FIG. That is, in FIG. 3, the right vertical roll 4
is set to a position moved to the left compared to FIG. 2 in order to lower the right 7 lunges. Lower horizontal roll 1
is moved upward and set so as to contact the vertical roll 4 at the inclined part "a". The lower horizontal roll 2 is moved upward by an amount equal to the sum of the amount of movement of the lower horizontal roll 1 and the amount of reduction of the web portion, and is set. Roughly speaking, the left vertical roll 3 is set corresponding to the amount of reduction of the left flange and projection.

By using these setting methods, the effects described above can be expected.

The rolled material then undergoes a final pass in the universal rolling process shown in FIG. Here, the lower horizontal roll 1 is in contact with the right vertical roll 4 at the inclined part a" and the vertical part "b", which prevents the upper horizontal roll 1 from moving to the right as in Fig. 2.3. .The lower horizontal roll 2 is also in contact with the right vertical roll 4 at the vertical portion of "C", and movement in the right direction is regulated similarly to the lower horizontal roll 1. In this way, the web portion and flange portion・Since the rolling reduction ratio of the protrusions can be made the same, bending and twisting of the rolled material does not occur.

Next, in the shaping rolling shown in FIG. 6, the lengths of the flange portions and projections are adjusted. The shaping rolling hole shown in Figure 5.6 is cut into a set of rolls, and the shaping rolling mill moves perpendicularly to the rolling line and horizontally in response to the progress of rolling. Alternatively, it is a normal rolling method that makes it possible to utilize the groove shape shown in FIG. Here, as shown in Figures 2 to 4, we have shown an example of rolling in 3 passes by changing the roll set with the same roll hole type in the universal rolling process. It is also possible to take a higher number of passes.

Next, in the finishing universal rolling shown in FIG. 7, vertical rolls 7.8 are brought into contact with the side surfaces of the upper and lower horizontal rolls 5, 6 to prevent the upper and lower horizontal rolls 5.6 from moving in the left-right direction, and the flange portion and J7 height of the protrusion to a predetermined dimension.

(Effects of the Invention) As explained above, according to the present invention, in the universal rolling process that performs multiple passes when manufacturing asymmetric section steel such as channel steel with plunger, lateral movement of the upper horizontal roll due to thrust is prevented, It is possible to obtain a predetermined thickness of the protrusion, and rolling can be performed without bending or twisting.

[Brief explanation of the drawing]

Figures 1 to 7 show the rolling method of the protrusion and groove shaped steel according to the present invention. Figure 1 is the final pass of the rolling process to produce an intermediate rough shaped steel piece, and Figures 2 to 4 are the same. A universal rolling process using rolls and performing three passes by changing the roll set gap, FIG. 5.6 shows a shaping rolling process, and FIG. 7 shows a finishing universal rolling process. Figure 8 is a product diagram of an asymmetric channel steel with protrusions, Figures 9 to 13 show the conventional rolling method of channel steel with protrusions, and Figures 9 and 1θ are rough shapes for producing intermediate rough shaped steel pieces. - Intermediate rolling process, Figure 11 shows the universal rolling process, Figure 12 shows the shaping rolling process, and Figure i13 shows the final universal rolling process. FIG. 14 shows a conventional method of rolling a channel steel with projections, which is different from FIGS. 9 to 13. 1.5...-L horizontal roll, 2,6...lower horizontal roll, 3.7...left vertical roll, 4,8...right vertical roll, °a°"...tilt Oblique part.

Claims (1)

[Claims] When manufacturing asymmetric sections such as channel steel with projections by rolling including a universal rolling process with multiple passes,
A sloped portion having a certain length is formed on the non-rolling surface of one of the upper and lower horizontal rolls and one of the left and right vertical rolls, and rolling is performed with the sloped portions of both in contact and engaged during all rolling passes. A universal rolling method for asymmetrical steel sections.