JPH08252729A - Manufacture of long steel plate - Google Patents

Abstract

PURPOSE: To restrain deformation at cutting off by providing intermittent slit cut parts leaving uncut parts along prescribed cutting lines of a steel plate, and after drilling on prescribed positions by a NC drilling machine, cutting the uncut parts on the cutting lines so as to manufacture a plurality of perforated steel plates. CONSTITUTION: Intermittently cut slits 2 are provided along cutting lines of prescribed width, flange width B, web width B, on a large-sized steel plate 1 of length L and width B. Namely uncut parts are provided on both end parts, the vicinity of bolt hole positions, and the positions where restraint is exhibited so as not to generate deformation inside and outside of the plane of steel plate 1 at cutting the slits 2. The position of slit 2, the length S1 of slit, and the length S2 of uncut part are decided by a handling method in case of cutting the uncut parts of the steel plate 1 after cutting the slits or moving them for assembling into a shaped steel. Next after drilling bolt holes on the end parts of flange and web materials by a NC drilling machine, the uncut parts, the surplus length parts are cut off by a gas or plasma cutter so as to manufacture a long steel plate.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for cutting steel plates used for girders, beams, stiffeners, auxiliary members, etc. of bridges, buildings and other steel structures.

[0002]

2. Description of the Related Art Conventionally, welding of steel structures such as bridges and buildings I
In the production of shaped steel, H-shaped steel, etc., in general, a large steel plate is cut into individual long steel plates having the final product size, and if necessary,
After performing bolt hole drilling and plate piecing welding at predetermined locations, a long steel plate was assembled and welded. Then, in each process, the bending deformation that occurs during cutting and welding is properly corrected.

[0003]

The conventional cutting method as described above has the following problems.

(1) When a long steel plate such as a flange or a web of welded steel or a stiffening material is obtained from a large plate 12 by gas cutting or plasma arc cutting as shown in FIGS. If the wire 14 is cut at a stretch over the entire length of the wire 14, a large bend δ occurs in the cut long steel plate 13 due to thermal deformation at the time of cutting, and it is necessary to correct the large bend of each long steel plate before and after the punching process. there were. This big bend δ is
The narrower the width of the member of the long steel plate, the more remarkable. There is a method of using a laser cutting device as a cutting method that does not cause a large bending due to thermal deformation, but the device price is expensive.
There is also a method of cutting while cooling with a mechanical cutting device such as a gold saw, but there is a problem that efficiency is low.

Further, in the process of forming the bolt holes in the member, the cut member is fixed to the floor surface with a fixing jig so as not to move, and then a drilling process is performed with a radial drilling machine or the like. Replacement was required, and the work of fixing and removing was complicated.

(2) In the case of joining steel plates having different plate thicknesses and materials by welding, in plate joint welding of steel plates having narrow widths as described above, individual thin steel plates cut from a large plate are used. After assembling each, welding of the joint was performed. For this reason, it is difficult to secure the accuracy of assembling the long steel plates in the plate joining process, and bending is caused by welding deformation. In addition, in addition to increasing the number of assembling and welding points, in general, for joints with short welding length,
Since welding is performed using a semi-automatic carbon dioxide shield arc welding device, there is a problem that the welding speed is slow and plate joining work is inefficient.

An object of the present invention is to solve the above problems, to provide a method for cutting a steel sheet which suppresses deformation at the time of cutting and which efficiently carries out drilling and plate joint welding.

[0008]

Means for achieving the object of the present invention are summarized as follows.

An intermittent slit cutting portion provided with a cutting residue is provided along a predetermined cutting line of the steel sheet, and after punching is performed at a predetermined location with an NC drilling machine, the uncut portion of the cutting line is removed. A method for producing a long steel plate, which comprises cutting and separating to produce a plurality of perforated steel plates.

After performing plate joint welding of a steel plate having an intermittent slit cutting portion provided with a cutting remainder along a predetermined cutting line of the steel sheet, the uncut portion of the slit cutting line is cut and separated, A method for producing a long steel sheet, which comprises producing a single piece of plate-jointed steel sheet.

[0011]

That is, in the present invention, the steel sheet is not cut at a stretch over the entire length of the predetermined cutting line, but the uncut portion is intermittently provided, so that the bending deformation due to heating at the time of cutting is suppressed by the restraint of the uncut portion. In this state, the hole is punched and the welding is performed. Especially, the present invention has a great effect when applied to a long plate which is significantly bent and deformed during cutting and plate joint welding. That is, in the production of a plurality of long steel plate members that require bolt drilling and plate piecing welding, the steel plate is intermittently cut along a predetermined cutting line, and the members are not completely separated. Manufacture slit cutting steel plate. Next, the slit-cut steel plate is set on a working table, and after punching and plate-joint welding, the uncut portion is cut. As a result, it is possible to carry out drilling, plate welding, and cutting work with one work set, and to efficiently manufacture multiple long steel plates that have little bending and have been subjected to bolt hole drilling and plate welding. You can

[0012]

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a plan view of a slit steel plate according to the present invention, in which a large steel plate 1 having a length L and a width B is attached to a flange width B1.
A slit cutting portion is intermittently provided along a cutting line of a predetermined width of the web width B2, and a bolt hole 3 is provided at an end portion. The slit cutting part is an automatic gas cutting or an intermittent cutting in which slits 2 cut using an automatic plasma arc cutting machine and uncut portions are alternately arranged.

The arrangement of the length S1 of the slit 2 and the length S2 of the uncut portion and the respective lengths of the interrupted cutting are the width of the steel plate, the thickness of the steel plate, the position of the hole, and the presence or absence of handling of the slit steel plate 1. Determine according to the suspension method.

That is, uncut portions are provided at both ends of the slit steel plate 1 and near the positions where the bolt holes are formed. In addition, the uncut portion is also provided at a position where a restraining force is exerted so that in-plane and out-of-plane deformation of the steel sheet does not occur during slit cutting.

Further, when the uncut portion of the slit-cut steel sheet 1 is cut or moved for assembling into a shaped steel, the position of the slit 2 and the length of the slit length S1 and the uncut portion S2 are determined by the handling method. I need to decide. As shown in FIG. 4, when the hacker 6 is used to suspend and handle four ends of the steel sheet 1, the bending moment of the weight of the steel sheet due to the hanging point widths B0 and L0 in the width direction and the length direction of the steel sheet 1 is calculated. Considering this, it is necessary to prevent the slit cutting portion from locally deforming, and it is necessary to set the uncut portion S2.

For example, as a specific example, plate thickness t having bolt holes at both ends t = 12 mm, flange width B1 = 300 m
m, a web height B2 = 600 mm, and a length L = 10 m, two I-shaped flange materials and one web material are manufactured by slitting a steel plate having a width B = 1206 mm and a length L = 10.1 m. Slit cutting is performed with a total cutting length S1 of 9600 mm, a total uncut portion length S2 of 400 mm, a surplus length of both ends of 50 mm, and a slit cutting table S4 of 3 mm. At this time, the uncut portions S2 are 2
It is advisable to provide them in the vicinity of the hacker's hanging position by 00 mm, and divide the slits into 3 places.

As a handling method, a slender lifting magnet 7 as shown in FIG. 5 is used, or a means is provided below the slit-cut steel plate 1 to widen the support surface through a receiving material so that a bending moment is less likely to occur in the large plate. When used, the uncut portion S2 can be shortened.

When it is necessary to reverse the slit-cut steel plate 1 for assembly processing, it is necessary to lengthen S2 so that the slit cut portion is not locally deformed during the reversing work.

The bolt holes provided in the end portions of the flange and the web material are usually processed by using an NC girder radial drilling machine, but may be processed either before or after slit cutting.

Not only before the slit cutting but also after the slit cutting, the steel plate (work) 1 is set on the processing table of the drilling machine in order to perform the punching work in the state of the large plate. Just put it down,
Even if it is light, it only needs to be fixed once and work is extremely easy. Further, input of NC data of drilling coordinates to the NC girder radial drilling machine and teaching of the work origin on the large plate can be processed as one plate.

When a large plate that is automatically slit by an NC girder radial drilling machine is subjected to punching, it is necessary to determine the hole position in consideration of the slit cutting table.

The steel sheet cut by intermittent slits is made into a long steel sheet by cutting the uncut portion and the extra length portion with a manual or automatic gas cutting machine or a plasma cutting machine and separating them.

FIG. 2 shows a long steel plate such as a flange 4 and a web 5 which is manufactured by the cutting method of the present invention and constitutes a welded steel having a bolt hole at a material end.

FIG. 3 shows this long flange 4 and web 5.
It is a perspective view of I type steel assembled using.

FIG. 6 is a plan view of a slit steel plate according to the present invention, in which the lengths of the different materials and plate thicknesses are La + S.
3, Lb + S3 two steel plates (9a, 9b). This steel sheet is slit-cut so as to satisfy the same conditions as in the above-mentioned example, and each steel sheet has a welding groove 8 along the butt joint line.

FIG. 7 shows a length L (= La +) obtained by joining the two slit-cut steel plates 9a and 9b shown in FIG. 6 by a highly efficient welding method such as submerged arc welding.
Lb), a plate joint slit cutting steel plate 10 having a width B, and the slits 2 are on the same cutting line of a predetermined width. The uncut S2 and the extra length portion S3 of the plate joint slit-cut steel plate 10 are cut to obtain a plate-joined long steel plate having a predetermined shape.

FIG. 8 shows a long steel plate (11a, 11b) made of the present invention, such as a flange material of welded steel having a plate joint welded portion 8'having a length L and widths B3, B4.

In the case of a necessary member for drilling a bolt hole, the hole is drilled after plate joint welding, that is, in the state shown in FIG.
In this case, it is efficient to use an NC girder radial drilling machine. Further, when cutting the extra length portions S3 at both ends, it is necessary to consider the shrinkage due to the plate joint welding.

[0030]

According to the present invention, since a slit cutting portion is intermittently provided along a predetermined cutting line of a steel plate, and a punching process is performed in a large plate state before the steel plate is separated, a large NC drilling machine is provided. Can be used, and the number of times the steel plate is held horizontally, the drilling machine is set on the working table, and the number of times of teaching the member origin to the NC drilling machine can be greatly reduced, and the efficiency of drilling work can be improved.
Also, for members that require plate joint welding, plate joint welding is performed in the state of the large plate before separating the steel plates, so compared with the conventional method of joining individual steel plates by semi-automatic carbon dioxide arc welding etc. Since it is possible to significantly reduce the movement of steel plates, the number of times of assembling, and the welding setup, and also to increase the welding length, it is possible to employ a highly efficient welding method such as submerged arc welding. Further, since the slits are intermittently cut along the predetermined cutting line of the steel sheet, thermal deformation during cutting can be restrained, and after the steel sheet is gradually cooled, the uncut portion is cut and separated to suppress bending deformation due to cutting. Therefore, the correction work can be omitted or simplified.

[Brief description of drawings]

FIG. 1 is a plan view of a slit steel plate according to the present invention.

2 (a) and 2 (b) are views showing a long steel plate which is manufactured by a cutting method of the present invention and constitutes a welded steel having a bolt hole at a material end.

FIG. 3 is a perspective view of I-shaped steel assembled using a long flange and a web manufactured by the cutting method of the present invention.

FIG. 4 is a view showing a hacker used for handling a steel plate.

FIG. 5 is a view showing a lifting magnet used for handling a steel plate.

FIG. 6 is a plan view of two slit steel plates having different materials and thicknesses according to the present invention.

7 is a plan view of a steel plate obtained by joining two slit-cut steel plates shown in FIG. 6 together.

FIG. 8 is a view showing a long steel plate having a plate joint weld manufactured by the cutting method of the present invention.

9 (a) and 9 (b) are views showing a long steel plate having a large bend due to a conventional cutting method and thermal deformation at the time of cutting.

[Explanation of symbols]

1 ... Slit cutting steel plate 2 ... Slit 3 ... Bolt hole 4 ... Flange 5 ... Web 6 ... Hacker 7 ... Lifting magnet 8 ... Welding groove 8 '... Welding part 9 ... Slit steel plate 10 ... Plate joint Slit cutting steel plate 11 ... Plate joint Long steel plate 12 ... Large plate 13 ... Long steel plate 14 ... Cutting line

Claims (2)

[Claims] 1. An uninterrupted slit cutting portion provided with an uncut portion is provided along a predetermined cutting line of a steel sheet, and after punching is performed at a predetermined position with an NC drilling machine, the uncut portion of the cutting line is left. A method for manufacturing a long steel plate, which comprises cutting a plurality of parts and cutting them to manufacture a plurality of perforated steel plates. 2. A steel sheet having an intermittent slit cutting portion provided with a cutting residue is welded along a predetermined cutting line of the steel sheet, and then the uncut portion of the slit cutting line is cut and cut off. A method for manufacturing a long steel plate, which comprises manufacturing a plurality of plate-jointed steel plates.