JP3431766B2 - Cutting method for shear of section steel - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shear cutting method for shaped steel, and more specifically, it has a flange thicker than the web at both ends of the web, such as general channel steel and H-shaped steel. The present invention relates to a shear cutting method in which a shaped steel is sheared by using a pair of forming blades.

[0002]

2. Description of the Related Art Generally, cold sawing of shaped steel is generally applied with a cold saw, but in recent years, in order to improve the cutting efficiency, shear cutting of multiple rows at the same time is possible. Application is in progress. Further, in the conventional shearing of channel steel or H-section steel, it is a schematic explanatory diagram thereof [FIG. 4].
As shown in ((a) Figure is a partially broken front view and (b) figure is a side view), sharpen the tip between a pair of fixed blades (11), (12) with grooved blades of the same shape. Although the moving blade (13) was lowered to perform punching shearing, this method easily deforms the cutting surface and causes cutting loss.Recently, it corresponds to the cross-sectional shape of the section steel to be cut. Shear cutting by a pair of full-scale blades provided with a hole-shaped blade is used.

In the conventional shear cutting with the above-mentioned conventional full-scale blade,
As shown in the side view (Fig. 2) (a),
Using, for example, a channel-shaped fixed blade (1) provided with hole-shaped blades (2), (4) corresponding to the cross-sectional shape of (S) and a movable blade (3), for example, cutting channel steel . Here, the hole-shaped blade (2) of the fixed blade (1) is
Outside of one flange (F) of shaped steel (S) and web (W)
Each of the inner peripheral portion (the portion indicated by the thick line in the drawing) corresponding to the lower side and the region from the inner side of the other one flange (F ′) to the root R is the first flange cutting blade ( 2a), the web cutting edge (2b) and the second flange cutting edge (2c), and the inner peripheral portions other than that are formed in the relief portions (2d), (2e), and the moving blade (3) The hole-shaped blade (4) is a flange (F) of one of the shaped steel (S).
Inner side of the web, upper side of the web (W), and outer side of the other one flange (F ') The cutting edge (4a), the web cutting edge (4b) and the second flange cutting edge (4c) are provided with inner peripheral portions other than the above in the relief portions (4d) and (4e). Further, the fixed blade (1) is attached to a blade holder of a shear cutting machine (not shown), the movable blade (3) is attached to the lower end of the slide head which is inclined and raised at a predetermined angle, and the movable blade (3) is , Same (a)
As shown in the figure, both hole shaped blades allow the shaped steel (S) to pass.
The mounting position is adjusted so that the reference state in which (2) and (4) are overlapped becomes the upper limit position. Then, in this reference state, the shaped steel (S) is fed into both hole-shaped blades (2), (4) by a predetermined dimension, and then by the operation of the slide head,
As shown in Fig. (b), the movable blade (3) is tilted with respect to the web (W) and the flanges (F) and (F ') (35
Depth diagonally downward (in the direction of the arrow in the figure) at an angle of 45 degrees to 45 degrees, and its hole-shaped blade (4) the inner cutting edge (4a), (4b), (4c)
Simultaneously contact both flanges (F) and (F ') sides of the shaped steel (S) and the upper surface of the web (W) to start cutting, and in the process of moving to the one-dot chain line in the figure, a constant rate Cutting is performed by causing plastic deformation (cutting) and subsequent shearing. Also, in the case of relatively small shaped steel (S), multiple pairs of fixed and movable blades (1),
Attach (3) to the shear cutting machine and cut multiple lines in multiple rows at the same time.

[0004]

However, in the above-mentioned conventional shear cutting, channel steel or H steel is produced without causing cutting loss.
Although it is possible to efficiently cut a shaped steel or the like, there is a problem that the web which should be straight is likely to be bent and deformed, which deteriorates the shape quality of the cut product. That is, in the above-mentioned conventional shear cutting, the movable blade (3) is moved diagonally, and the respective cutting blades (4a), (4b), (4c) of the hole-shaped blade (4) of the shaped steel (S) Attempting to cut both flanges (F), (F ') and the web (W) at the same time by simultaneously contacting the sides of both flanges (F), (F') and the upper surface of the web (W) to start cutting. However, since the flanges (F) and (F ') are thicker than the web (W), the cutting reaction force of the flanges (F) and (F') is greater than that of the web (W). Since the moving blade (3) also becomes larger, the moving blade (3) moves in the web (W) direction by the gap and elastic deformation of each working part of the shear cutting machine, as shown by the arrow in (a) of Fig. 3. It is moved out of the way and begins to cut the web (W) first. On the other hand, shaped steels such as general channel steels and H-shaped steels conforming to JIS are made of general structural steels, and in cold shearing thereof, 20% or more of the thickness, 25
When cut to about%, shearing occurs at once and the cutting is completed. Therefore, the cutting starts first, and the shearing of the web (W) portion that is thinner than the flanges (F) and (F ') begins earlier, and as a result, the cutting of the web (W) is completed earlier and both flanges are completed. The outside of the roots of (F) and (F ') is delayed in cutting, and as shown in (b), the end of the web (W) of the cut shaped steel (S) is directed downward. Bending deformation occurs. Also,
This becomes remarkable as the section steel to be cut becomes larger.

The present invention has been made in order to solve the above-mentioned problems of the prior art, and a shaped steel having a flange thicker than the web at both ends of the web such as a channel steel and an H-shaped steel. An object of the present invention is to provide a shear cutting method for a shaped steel, which can cut a web with high shape accuracy without causing bending deformation of the web.

According to a first aspect of the present invention, both ends of the web are
Section steel with a flange thicker than the web
Having a hole-shaped blade having a shape corresponding to the cross-sectional shape of the shaped steel
Feed it into the hole-shaped blade of the pair of forming blades,
Angled with respect to each of the shaped steel web and flange
Shear cutting method for shaped steel that shears by moving relative to the direction
The average thickness of the flange and the thickness of the web
20% to 25% of the difference between the pair of forming blades, equidistant
Notch into the flange and notch into the web
Shearing method for shaped steel characterized by being preceded by
Is the law.

According to a second aspect of the invention, the pair of forming blades are
It consists of a moving blade and a fixed blade, and the average thickness of the flange
The transfer to a value of 20% to 25% of the difference from the web thickness
Set from predicted value or actual measured value of blade escape in web direction
The value of the pair that is equidistant to the value obtained by adding the escape correction value
Cut the notch into the flange of the forming blade to the web.
Shearing of the shaped steel according to claim 1, which is preceded by embedding.
It is a cutting method. In the invention according to claim 3, the shaped steel is groove-shaped.
A method for shearing a shaped steel according to claim 1 or 2, which is steel.
Is.

According to a fourth aspect of the present invention, the web is provided on both ends thereof with
Section steel with a flange thicker than the web
Having a hole-shaped blade having a shape corresponding to the cross-sectional shape of the shaped steel
Feed it into the hole-shaped blade of the pair of forming blades,
Angled with respect to each of the shaped steel web and flange
Shear cutting method for shaped steel that shears by moving relative to the direction
At the beginning of shearing of the flange and shearing of the web.
The pair of all-purpose blades so that the start and end of the break are almost at the same time.
Notch into the flange and notch into the web
Shearing method for shaped steel characterized by being preceded by
Is the law.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. [Fig. 1] is an explanatory view of an embodiment of a shear cutting method of the present invention, in which (a) is a starting point of cutting of a shaped steel, and (b) is a fixed blade and a moving blade in the middle of cutting. It is a side view which shows the positional relationship with. The fixed blade and the movable blade used in this example are basically the same as those shown in [Fig. 2] except that the configuration of the cutting blade of the movable blade is partially different. 2] and the description thereof will be omitted.

In this example, as shown in FIG. 1, a pair of fixed blades of the full-form blade type having hole-shaped blades (2), (4) having a shape corresponding to the cross-sectional shape of the shape steel to be cut ( 1) and the movable blade (3) are used to form a section steel (S) (in this example, a channel steel made of JIS; SS400 material)
Shear cut. In addition, the fixed blade (1) is on the blade holder of a shear cutting machine (not shown), and the movable blade (3) is 45
Attached to the lower end of the slide head of the shear cutting machine, which is adjusted to tilt up and down at an angle of
The movable blade (3) should be installed at its mounting height position so that the reference state in which both hole-shaped blades (2), (4) are overlapped to allow passage of the shape steel (S) to be cut is the upper limit position. adjust.

Here, the movable blade (3) is moved obliquely downward by 45 degrees to move the first and second flange cutting blades (4a) on the inner circumference of the hole-shaped blade (4) as shown in FIG. ), (4c) contacts the side surfaces of both flanges (F), (F ') of the shaped steel (S), that is, at the start of cutting, the web cutting edge (4b) and the shaped steel (S) Web (W)
The web cutting blade (4b) has a short blade height in the up-down direction so that a delay gap α set by the following equation can be secured between the upper surface and the upper surface. α = 0.25 (t ₁ −t ₂ ) −−− where t ₁ is the average thickness of the flange and t ₂ is the thickness of the web.

In the shear cutting of the present example using the fixed blade (1) and the movable blade (3) having the above-mentioned structure, similarly to the above-mentioned prior art, in the standard state in which the movable blade (3) is positioned at the upper limit, the shaped steel (S) is fed into both hole-shaped blades (2) and (4) by a predetermined size, and then the movable blade (3) is moved to the web (W) as shown by the arrow in the figure by the operation of the slide head. ) And flanges (F), (F ')
For each, descend at an angle of 45 degrees. At this time, first, as shown in (a), the first and second flange cutting blades (4a) on the inner circumference of the hole-shaped blade (4) of the movable blade (3),
(4c) contacts the sides of both flanges (F) and (F ') of the shaped steel (S) to start cutting, and then the web cutting edge (4b)
Is delayed by the above-mentioned delay clearance α, and the web of the shaped steel (S)
(W) The cutting starts upon contact with the upper surface.

Here, as mentioned above, in the cold shearing of general structural steel such as JIS; SS400 material, the shearing starts at a cut of about 20 to 25% of its thickness, and at this point the actual cutting However, in this example, the thick flange (F), the cutting of the (F ') portion, only the delay gap α of the web cutting edge (4b), that is, the flange (F), (F') 25% of the thickness of the web and 25 of the thickness of the web (W)
Since it is preceded in the web (W) direction by an amount equal to the value of the difference with%, the start of shearing at both flanges (F), (F ') and the web (W) is set at almost the same point. As a result, the flanges (F), (F ') and the web (W) can be cut almost at the same time, and bending deformation of the web (W) can be prevented.

In the above example, the delay gap α of the web cutting edge is equal to the difference between 25% of the flange thickness and 25% of the web thickness, but this is the minimum required condition. However, in the case of a relatively large shaped steel or a shaped steel in which the difference between the flange thickness and the web thickness is larger and the cutting reaction force of the flange portion at the time of cutting is large, the delay gap α ′ is Set by formula. α ′ = 0.25 (t ₁ −t ₂ ) + β −−− where t ₁ is the average thickness of the flange, t ₂ is the thickness of the web, and β is the gap of each working part of the shear cutting machine at the time of cutting. And a relief correction value set from a predicted value or a measured value of the clearance of the moving blade in the web direction due to elastic deformation.

Then, the flange portion is cut ahead of the web direction by the delay gap α'including the relief correction value β so that the start of shearing at the flange portion coincides with the start of shearing at the web portion. Or, by making it earlier than that, it is possible to prevent the cutting of the web portion from being completed early and bending deformation. Further, by this, the gap of each operating portion of the shear cutting machine and the deviation of the cutting edge due to the elastic deformation can be corrected, and a large shaped steel can be cut with high shape accuracy.

In the above example, the cutting of the channel steel was described, but the present invention is not limited to this. For example, the shape steel to be cut is thicker than the web at both ends of the web. The same effect can be obtained by applying to a general H-section steel having a flange. Further, in the above example, a pair of fixed and movable blades is described, but this is for the sake of simplicity of explanation. In practice, a plurality of pairs of fixed and movable blades are attached to the shear cutting machine, Shaped steel can be cut in multiple rows at the same time. Further, the number is set depending on the size of the shaped steel to be cut and the capacity of the cutting machine.

[0017]

As described above, according to the shear cutting method of the present invention, shaped steel having a flange thicker than the web at both ends of the web, such as channel steel and H-shaped steel, is used. It is possible to cut the web with high shape accuracy without causing bending deformation of the web.

[Brief description of drawings]

FIG. 1 is an explanatory view of an embodiment of a shear cutting method of the present invention, in which (a) is a starting point of cutting of a shaped steel, and (b) is a diagram showing a fixed blade and a movable blade in the middle of cutting. It is a side view which shows a positional relationship.

2A and 2B are explanatory diagrams of a shear cutting method using a conventional full-scale blade, in which FIG. 2A is a side view showing a configuration arrangement of a fixed blade and a movable blade, and FIG. 6 is a side view showing the positional relationship between the fixed blade and the movable blade in FIG.

FIG. 3 is an explanatory diagram of web bending deformation related to shear cutting by a conventional forming blade.

4A and 4B are schematic explanatory views of a conventional cutting method by punching shear, in which FIG. 4A is a partially cutaway front view and FIG. 4B is a side view.

[Explanation of symbols]

(1) --Fixed blade, (2) --Hole shaped blade, (2a)-First flange cutting edge, (2b)-Web cutting edge, (2c)-Second flange cutting edge, (2
d)-relief, (2e)-relief, (3)-moving blade, (4)-hole blade, (4a)-first flange cutting edge, (4b)-web Cutting edge,
(4c)-second flange cutting edge, (4d)-relief, (4e)-relief, (S)-section steel, (F), (F ')-flange, (W ) --Web,
α--lag gap, α '-lag gap, β--runout correction value, t ₁
--Average flange thickness, t ₂ --Web thickness.

Continuation of the front page (56) References JP-A-5-57523 (JP, A) JP-A-10-80820 (JP, A) Actual development Sho-64-56920 (JP, U) (58) Fields investigated (Int .Cl. ⁷ , DB name) B23D 23/00 B23D 15/00-15/04

Claims (4)

(57) [Claims] 1. A pair of forming blades having a cross-section shaped steel having flanges thicker than the web at both ends of the web, and having a pair of hole-shaped blades having a shape corresponding to the cross-sectional shape of the shaped steel. In the shear cutting method of the shaped steel, which is fed into the blade and sheared by relatively moving the pair of full-form blades in an oblique direction inclined with respect to the web and the flange of the shaped steel , respectively.
20% to 25% of the difference between the average thickness and the thickness of the web and
Cut equidistantly into the flange of the pair of mold blades
A method for shearing a shaped steel, characterized in that the incision precedes the incision in the web . 2. The pair of forming blades are composed of a movable blade and a fixed blade.
And the average thickness of the flange and the thickness of the web
The value of 20% to 25% of the difference causes the movable blade to escape in the web direction.
The relief correction value set from the predicted
The same distance as the value obtained, the flange of the pair of forming blades
The method of shear cutting of a shaped steel according to claim 1 , wherein the cut into the web precedes the cut into the web . 3. The section steel according to claim 1, wherein the section steel is a channel steel.
2. The shear cutting method for shaped steel according to 2. 4. A web having a thicker wall than the web at both ends of the web.
Change the cross-section shape having a lunge into the cross-section shape of the shape steel.
Within the hole-shaped blade of a pair of general-shaped blades that have a correspondingly shaped hole-shaped blade
Infeed, and the pair of forming blades are used to form the web and flange of the shaped steel.
Relative movement in the diagonal direction that tilts with respect to each
In the shear cutting method of the shaped steel to be cut,
The beginning of shearing and the beginning of shearing of the web are almost at the same time.
Cut into the flange of the pair of forming blades so that
That the incision precedes the incision in the web
Characteristic shearing method for shaped steel.