JPH06142913A - Method for edge cutting - Google Patents

Abstract

PURPOSE:To cut an edge on a steel plate in which a side face having an angle other than the right angle is crossed with a end face having the edge cut, in a good state. CONSTITUTION:In the case that the side face 1b is crossed with the end face 1a having the edge cut 4 to be cut at an angle alpha other than the right angle, a cutting torch 2 is faced to the end face 1a, the angle in the plane of the torch 2 is set at alpha and also the angle in vertical plane is set at beta that is the angle of the edge cut 4. After that, the cutting torch 2 is faced to an end part of the end face 1a, the steel plate 1 is preheated, the cutting of the shear-pin 4 is started and also progressed. Since the preheating of the steel plate 1 is executed onto the end face 1a, preheating effect with a preheating flame is not prevented and a good preheated state is maintained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of cutting a serpin on an end surface of a steel plate.

[0002]

2. Description of the Related Art When a steel sheet is cut, the cutting surface is cut so that the cut surface is perpendicular to the surface of the steel sheet, and the cut surface has an angle of 30 to 35 degrees with respect to the vertical direction of the surface of the steel sheet. The groove is often cut as described above. However, a hull member, a bridge member, or the like may be cut so that the angle of a cutting surface called a surpin with respect to the steel plate surface is larger than the angle.

A method of cutting the surpin will be described with reference to FIG. In the method shown in FIG. 5A, cutting is performed by a cutting torch 52 that is inclined at an angle corresponding to the angle of the serpin arranged on the front surface side of the steel plate 51. In this method, there is a limit to the distance that the cutting torch 52 is brought close to the surface of the steel plate 51, and the crossing angle between the cutting torch 52 and the surface of the steel plate 51 is small, so that the function of the preheating flame can be sufficiently exerted. Independent preheating torch near the cutting line
53 need to be placed. In addition, slag generated by cutting may adhere to the cut surface and damage the surface.

The method shown in FIG. 2 (b) relates to an improvement of the above method, in which a cutting torch 52 inclined at an angle corresponding to the angle of the serpin is arranged on the end face side of the steel plate 51 for cutting. Is. With this method, the function of the preheating flame can be fully exerted. In particular, by forming the cut surface by the serpin on the lower surface side of the steel plate 51, it is possible to obtain a good cut surface without the slag generated by the cutting damaging the cut surface.

In any of the above methods, the cutting of the serpin has an apparently large cutting thickness and the scrap has a wedge shape, so that the end of the scrap is melted and a cutting oxygen flow is generated. It is difficult to obtain a good cut surface due to disturbance.

As described above, cutting the serpin belongs to the difficult technique. Therefore, when cutting the surpin, the steel plate 51
The plane shape of is limited to a rectangle. For example, as shown by the alternate long and short dash line in FIG. 4, when the planar shape of the product is such that the end face 51a where the surpin should be cut and the adjacent side face 51b intersect at an angle other than a right angle, the surpin is first cut from the end face 51a. After that, the steel plate is cut along the alternate long and short dash line (51b) to obtain a predetermined product.

[0007]

If the plane shape of the steel sheet is cut after cutting the serpin as described above, there is a possibility that the plane surface may be cut twice depending on the plane shape. Therefore, it is preferable to cut the planar shape of the steel plate into a desired shape and then cut the serpin from a predetermined end surface.

However, as shown in FIG. 4, when the side face 51b adjacent to the end face 51a to be cut with the surpin (the face indicated by the alternate long and short dash line) intersects at an angle other than a right angle, the starting point of cutting is from the cutting torch. There is a problem that it is located at the farthest position and the starting point cannot be effectively preheated. Further, even if the cutting is started, a new edge that is not preheated is always cut as the cutting progresses, and there is a problem that the cutting of the serpin cannot be continued in a stable state.

An object of the present invention is to cut a serpin under a good preheating condition even when the end face to be cut and the end face adjacent to the end face intersect at an angle other than a right angle. It is to provide a cutting method capable of performing.

[0010]

In order to solve the above problems, a method of cutting a surpin according to the present invention is to cut a surpin into a steel plate having a side surface intersecting with an end surface to be cut at an angle other than a right angle. In the method, after facing the cutting torch to the end face to be cut, the angle of the plane of the cutting torch is set so as to be parallel to the side surface intersecting with the end face, and the vertical angle of the serpin to be cut is set. It is characterized by setting the angle and then starting the cutting from the end of the end face to be cut.

[0011]

According to the above cutting method, even if the end face to be cut and the other side face intersect at an angle other than a right angle, the surpin can be cut by preheating in a good state. .

That is, the cutting torch is set to face the end face to be cut and the plane angle is set to be parallel to the adjacent side face, and the angle on the vertical plane is set to the angle of the serpin. Thus, the height of the cutting torch from the cutting start point can be set to a height at which the preheating flame can most effectively exert the preheating effect. Therefore, cutting of the serpin can be started and continued without the aid of another preheating torch.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the cutting method for the above serpin will be described below with reference to the drawings. 1A and 1B are views for explaining the posture of a cutting torch when carrying out the cutting method according to the present invention. FIG. 1A is a plan view, FIG. 1B is a side view, and FIG. 2 is a shape of a steel plate to be cut. FIG.

As shown in FIG. 2, the steel plate 1 is cut into a desired product shape in advance. That is, the side face 1b adjacent to the end face 1a to cut the surpin of the steel plate 1 is cut so as to intersect at an angle α which is an angle other than 90 degrees. The end surface 1a and the side surface 1b are cut at a right angle to the surface 1c of the steel plate 1.

As shown in FIG. 1, the cutting torch 2 is a holder 3 constructed so as to be adjustable at a desired angle in a plane parallel to the surface 1c of the steel plate 1 and in a plane perpendicular to the surface 1c.
Held in. The setting of the three-dimensional angle of the cutting torch 2 by the holder 3 may be performed manually, or a motor driven and controlled by a numerical controller or the like may be used.

When cutting a serpin with an angle β from the end face 1a of the steel plate 1, as shown in FIG. 1 (a), the cutting torch 2 is made to face the end face 1a of the steel plate 1 so that the plane angle is equal to the end face 1a. The angle in the vertical plane of the cutting torch 2 is set to the angle β which is the angle of the serpin, as shown in FIG.

After setting the three-dimensional angle of the cutting torch 2 as described above, the distance from the end face 1a of the cutting torch 2 is set to the height at which the steel plate 1 can be preheated most efficiently, that is, the cutting torch 2. Set the distance corresponding to the length of the white flame when the preheating flame is formed. Thus, the preparation for cutting the surpin on the steel plate 1 is completed.

Next, as shown in FIG. 3A, the cutting torch 2 is placed along the end of the end face 1a, and a preheating flame is formed at this position to start cutting. At this time, since the steel plate 1 is preheated to the end surface 1a, it is possible to improve the preheating efficiency. Therefore, it becomes possible to continue the cutting of the serpin with respect to the steel plate 1 under a favorable preheating state.

When the cutting torch 2 is detached from the end surface 1a of the steel plate 1, it is difficult to expect preheating of the steel plate 1 by the preheating flame. However, the steel plate 1 is continuously preheated by the heat generated by the combustion of iron due to the cutting, and the cutting of the serpin is continued, so that it is possible to cut the serpin 4 having the preset angle β in the steel plate 1.

[0020]

As described in detail above, according to the method for cutting a surpin according to the present invention, even a steel plate having a side surface intersecting with an end surface to be cut at an angle other than a right angle, It has a feature that it is possible to cut the serpin while maintaining a good preheating state.

[Brief description of drawings]

1A and 1B are views for explaining the posture of a cutting torch when a cutting method according to the present invention is carried out, where FIG. 1A is a plan view and FIG.
Is a side view.

FIG. 2 is a diagram illustrating a shape of a steel plate to be cut.

FIG. 3 is a diagram illustrating a conventional method for cutting a surpin.

FIG. 4 is a diagram illustrating a problem.

[Explanation of symbols]

 1 Steel Plate 1a End Face to Cut Serpin 1b Side 1c Surface 2 Cutting Torch 3 Holder 4 Serpin

Claims (1)

[Claims] 1. A method of cutting a serpin on a steel plate having side faces that intersect at an angle other than a right angle with respect to the end face to be cut, wherein a cutting torch is opposed to the end face to be cut, and then the end face is cut on the end face. Set the angle of the plane of the cutting torch so that it is parallel to the intersecting side face, set the vertical angle to the angle of the serpin to be cut, and then start cutting from the end of the end face to be cut. The characteristic cutting method of the serpin.