JPH012706A - Width reduction press - 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 [Industrial Application Field] The present invention relates to a width reduction press which increases the amount of width reduction per press to prevent buckling.

[Prior Art] Research is being conducted into using a press that can reduce the width of a material such as a slab by a press that can increase the amount of width reduction. Therefore, when width reduction is performed using a press, if the width of the plate is approximately 1,200 mm or more, and the plate thickness is approximately 250 to 300 mm, the material may buckle if the width reduction is 300 to 350 mm or more. Occur. In order to prevent this seat 1ζ-6 from being damaged, it is conceivable to provide a presser roll that presses the surface of the material.

[Problems to be solved by the invention] However, in the above-mentioned press, buckling cannot be completely prevented unless the rolls are placed at appropriate positions, and if pressure rolls are provided on both sides, the number of rolls increases. However, there are problems such as high installation costs and high operation and maintenance costs.

The present invention has been made in view of the above-mentioned circumstances, and is aimed at effectively suppressing buckling with a small number of presser rolls.

[Means for Solving the Problems] The present invention provides a mold for performing width reduction pressing of a material, and a presser roll having a diameter of approximately 600fflI11 or more and a body length of approximately 500 mm or less, which presses both sides of the material in the widthwise direction. The configuration is as follows.

[Function] When the presser roll presses the material from both sides of the center in the width direction and the die performs width reduction, no ridges will form on the shrine q even if the width reduction per time is large.

[Example] Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a plan view schematically showing the width reduction press of the present invention, in which 1 is a housing, 2a and 2b are reduction cylinders 3a.
, 3b is a pair of left and right molds that operate oppositely to roll down the width of the material 4 such as a slab, 5 and 6 are used to prevent the buckling of the holding member 1'44 from the upper and lower surfaces of the substantially central part of the material 4 in the width direction J. A pair of upper and lower presser rolls prevents this. This presser roll 5.6 has a diameter of about 600 ridges or more and a body length of about 50 DmI11 or less.

Next, the reason why the diameter D1 and body length of the presser rolls 5 and 6 are set to the above values will be explained based on data obtained from a hot steel model experiment.

The relationship between the diameter of the presser roll and Hertz's maximum contact pressure P is shown in Figure 2, and the limit stress for denting, where the material is succumbed to the pressing force of the presser roll and dented, is Po 'iPe Kg The diameter p of the presser roll at /+n+n2 is approximately GOOnon, and if the diameter is larger than that, only a dent will occur in the material 4'4. The shaded area A in FIG. 2 indicates the range of pressure Pe in which no dent occurs.

Note that the dent generation limit stress P is expressed by the following formula.

r03□ where ν1; Poisson's ratio of the material ν2; Poisson's ratio of the roll El; Young's modulus of the material E2, Young's modulus of the roll ro; Radius of the roll q; Load applied to the unit width of the material xglIIIIIIl Original slab width without the presser roll W. is 900■, 1200f
Width reduction ΔW for f1m and 1600mm materials, respectively
+ = 100mm, AW2-200mm, JWa −
Applying 300nm SΔWa -400mm and lowering the width,
When the graph shows whether buckling occurred in the material at that time, a graph like that shown in FIG. 3 was obtained.

FIG. 3 O shows the case where no buckling occurs, Δ shows the case of half buckling, and × shows the case where buckling occurs. From this graph, the slab width Wo is 9
In the case of 00m+n, the width reduction amount is AWa = 400m
Buckling does not occur even when the slab width is approximately m. is 120
In the case of 01, full buckling occurs when the width reduction amount is set to about AW3-300+++m, and when the slab width is Wo or 1600non, half buckling occurs when the width reduction amount is set to about AWr -2Of)offl.

Therefore, the range where semi-buckling or buckling occurs is △ in Figure 3.
The hatched area x is above the line drawn by 1, and this hatched area x is the required range of the presser roll. Also, from the shaded part ×, for example, if the slab width Wo is about 1050 mm,
When the width reduction amount is JW4-400 mm or more, half buckling or buckling is considered to occur.

Next, the relationship between the original slab width Wo and the dogbone foot length A when the above width reduction is performed without a presser roll is calculated as follows: fla A W2 , A W3.1JW4 (Specific u values are shown in Figure 3) ), the graph shown in Figure 4 is obtained. Also, width reduction QAW2, AW3, A
If the position where ten buckling occurs for every Wa is transferred to the graph of FIG. 4 in correspondence with the original slab width Wo, it becomes the position. Therefore, the shaded area X above the line obtained by connecting each .

The required range is the presser foot roll.

The length A of the dogbone in the graph of FIG. 4 indicates the length of the portion where the dogbone is generated, as shown in FIG.

By the way, in order to prevent buckling of the material, it is desirable that the body length of the presser roll is as long as possible.If the end of the presser roll is located at the area where the dogbone occurs after width reduction, the material t4 will be damaged due to width reduction. The presser foot roll may cause damage.

Therefore, it is necessary to set the body length of the presser roll so that it does not touch the dogbone of the material after width reduction, and the body length of the presser roll for this purpose is L-W. -ΔWn-2A.

For example, the original slab width W. = 12011 mm, the width reduction caused by buckling is A W 3-300 mm, and the length of the drag pawn is A -150 +++ m, so the body length of the presser roll is L - (1200-300).
-2x200 = 500mm, and in other cases approximately 50mm
It becomes about 0+nm. Therefore, the body length of the presser roll is 50
If the pressure is less than 01, the presser roll will not damage the dogbone generating portion of the material.

When width reduction is performed by pressing the center part of the material 4 in the width direction from the front and back sides with a presser roll 5.6 having a diameter of approximately 60 buttons or more and a body length of approximately 500 mm or less, each time Even if the width reduction amount is as large as 300 to 350fflIIl, buckling does not occur in the material 4.

It should be noted that the present invention is not limited to the above-described embodiments, and it goes without saying that various changes can be made without departing from the gist of the present invention.

[Effects of the Invention] According to the width reduction press of the present invention, buckling of the material can be effectively prevented by using a pair of presser rolls, and since the required number of presser rolls is the minimum, equipment costs, operation and maintenance costs can be reduced. Various excellent effects can be achieved, such as:

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram of one embodiment of the present invention, Fig. 2 is a graph showing the relationship between the diameter of the presser roll and Hertz's maximum contact pressure, and Fig. 3 is the width corresponding to the original slab width and width reduction amount. A graph showing the relationship with the reduction blade, Figure 4 is a graph showing the relationship between the original slab width and the dog bone foot length corresponding to the amount of width reduction, and Figure 5 is an explanation of the length of the dog bone foot caused by width reduction. It is a diagram. In the figure, 2a and 2b are molds, 3a and 3b are reduction cylinders, and 4
indicates the material, and 5 and 6 indicate the presser rolls.

Claims (1)

[Claims] 1) A mold that presses down the width of the material, and a mold that presses both sides of the material in the width direction, with a diameter of approximately 600 mm or more and a body length of approximately 5 mm.
A width reduction press characterized by having a pair of upper and lower presser rolls having a width of 00 mm or less.