JPS591149B2 - Steel fusing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for cutting steel materials by melting the contact portion of the flame with a combustion flame of gas ejected from a torch, and is particularly effective when cutting thick steel materials with oxygen. It is true.

As is well known, when cutting steel materials such as pipes, bars, and lumps using the combustion flame of a torch, there are two methods: gas cutting, in which high-temperature combustion gas is injected, and high-pressure oxygen gas or air is injected into the preheated steel material. There is oxygen fusing, which involves spraying and fusing, and either of these fusing methods melts an area of at least several tens of millimeters along the cutting line.

That is, as shown in Fig. 1, an imaginary cutting line a is defined on the steel material 1, the steel material 1 is placed on the receiving materials 2, 2 so that the cutting line a is not placed on the steel material 1, and the gas ejected from the nozzle 3 of the torch is combusted. When the flame is moved at low speed along the above cutting line a. A range b approximating the width of the combustion flame with cutting line a as the center is melted and cut, and the molten excess portion 4 corresponding to range b drips onto the side and bottom of the steel material 1, cools and solidifies, and becomes the steel material 1. Adheres firmly. Conventionally, the excess portion 4 that has been cooled and solidified must be peeled off by hitting it with a tool or the like, which is extremely time-consuming and may result in damage to the steel material.

Therefore, in order to minimize the occurrence of surplus parts.

Using an oxygen curtain type or double frame type fusing machine, the excess flow out is made soft and easy to remove, or the oxygen pressure at the time of fusing is increased to slow down the fusing speed.
Attempts are being made to minimize the amount of surplus flowing out.
However, none of these methods essentially prevents the outflow of surplus material, so removal work cannot be omitted.
Moreover, the fusing speed is significantly reduced, resulting in poor workability. The present invention has been proposed in view of the above, and involves applying a pre-formed adhesion prevention device to the position where the excess portion of the steel material is attached, allowing the excess portion that flows out during fusing to come into contact with the above-mentioned prevention device, and then applying the cooled and solidified excess portion to the steel material. It is designed to prevent contact and also to be easily peeled off from the preventive device.

Therefore, the present invention is essentially different from conventional methods of suppressing the generation of surplus parts! 2. Although the generation of surplus parts is allowed, it is designed to prevent them from adhering to the steel material.

To explain the present invention in more detail, when performing gas cutting or oxygen cutting, a cutting line a is set in advance on the steel material 11, and a cutting range b is assumed.

And, on the left and right edges b', b' of the fusing range b,
A pre-formed adhesion prevention tool 12 is applied. This adhesion prevention tool 12 prevents at least the melted surplus portion 14 in range b from adhering to the steel material 11 when the steel material is being cut by the combustion flame of the gas ejected from the torch nozzle 13. Even if it adheres to its own surface, it is a simple means,
For example, it can be easily peeled off by slight vibration or impact.

Therefore, the preventer 12 is made up of at least a pair of left and right preventers 15, 15 facing each other, and when applied to steel, the opposing edge 15' of each preventer 15 is aligned with the edge v. The shape of the preventive material 15 differs depending on the cross-sectional shape of the steel material 11.

That is, since this is to prevent the excess portion 14 from adhering when the steel material 11 is fused, the shape is sufficient to cover all the portions to which the excess portion 14 is likely to adhere. for that purpose. If the steel material 11 has a rectangular cross section, it is at least plate-shaped along the length direction of the edge v of the bottom surface of the steel material, or it is U-shaped in which the edge b'IlC of the bottom surface and the front and rear surfaces are applied.

On the other hand, if the steel material 11 is circular in cross section, at least the steel material 11
A semicircular shape that covers the lower half of is desirable. Further, the cross-sectional shape of the preventive material 15 may be rectangular, but it is preferably a shape that facilitates the scattering of the excess portion 14 outward by the flow of combustion flame when the steel material is fused.

To this end, as shown in FIG. 4, the facing surfaces 16 of each of the preventive members 15 are sloped so that the opposing distance between the two preventive members 15, 15 widens toward the end, or a plate material is used. As shown in FIG. 2, each prevention member 15 may have a rod shape with an inclined surface 16 facing the prevention member 15. When the preventive materials 15, 15 are applied to the steel material 11 in such a way that they face each other in the fusing range, the preventive materials 15, 15
, 15 can also function as a pedestal for supporting the steel material 11.

When the torch nozzle 13 is moved so as to face the cutting line a of the steel material 11, the steel material is fused.

In the case of gas cutting, the combustion flame directly heats the steel material and melts it. On the other hand, in the case of oxygen cutting, high-pressure oxygen or air is injected onto the preheated steel material, so the oxidation of the injected steel material portion is promoted, and the oxidized portion melts and scatters, leading to cutting. The surplus portion 14 that melts and scatters flows down from the fused portion through the opposing interval of the preventive material in a scattering state. Part of the prevention material 1
It adheres to the surface of 5. Therefore, it does not directly adhere to the steel material 11, and anything that adheres to the prevention material 15 can be easily peeled off and removed, and even during fusing, there is no chance of it falling under its own weight. As a component, it is necessary to have the ability to reliably peel off the excess part even under high temperature conditions, and if the preventive material also serves as a mounting table for steel materials, it is necessary to use a material that has a pressure resistance that can withstand even when the steel material is placed on it. The following three types of such components can be exemplified.

(1) The main components are a heat-resistant molten surplus and a removable composition.

(2) Those whose main component is a component that generates gas when heated and becomes an inorganic substance with a high melting point.

(3) When heated, it foams and expands in volume, and the excess portion that adheres can be peeled off.

In the above-mentioned (1), the main component is a heat-resistant composition such as graphite, mica, or gypsum, and a solvent or the like is mixed with this composition to form a preventive device in a desired shape.

Therefore, when the excess portion (due to fusing) adheres, the solvent component of the preventive material evaporates, but since the composition supports the steel material, the excess portion that has been cooled and solidified is easily peeled off. As the above-mentioned (2), it is possible to use a material whose main component is calcium carbonate, which generates carbon dioxide gas when heated at high temperature, or carbon, fiber, etc., which generate carbon dioxide gas when reacted with oxygen at high temperature.

Furthermore, as for (3) above, decomposition by high temperature heating,
Gas and melt are generated and foam. It is possible to use materials whose main components are carbonate, water glass, boric acid, etc., which expand in volume. In addition, as the composition (3), a mixture of a component that generates gas and a component that melts when heated can also be used. All of the above components are kneaded products whose main components are a filler and a binder. The prevention material can be formed by reducing the mixing ratio of the 6 binder and pouring it into a form into a plate or rod shape.

Furthermore, a mixture of the filler (1) or (2) and powder such as frit, which is solid at room temperature as a binder but melts and sinters with other ingredients when heated, is placed in a mold and made into a steel material. It can also be used as a preventive material by sintering it with the residual heat of the steel material or the heat from gas cutting.

By applying a preventive device pre-formed with a preventive material to the steel material, or by applying a composition and forming a preventive device by sintering at the time of fusing, the excess portion flowing out due to fusing will not adhere to the steel material. Moreover, it can reliably support steel materials.

Then, if the opposing preventive materials are connected by a connecting tool and the distance between the opposing preventive materials can be adjusted by operating the connecting tool, no matter what kind of nozzle is used or the width of the fusing range b. It can also be used when changing.

Also, if a leg rod is placed upright at one end of the preventer, a torch nozzle of a fusing device is attached to the tip of the leg lever, and the torch nozzle is positioned in the center of the opposing gap between the preventers and made movable, it is possible to prevent steel materials from being damaged. The fusing position of the steel material can be set simply by placing it on the tool.

FIG. 6 shows another example of the prevention material 15. That is, when molding the prevention material 15, either a thin molded material is adhered with an adhesive that is relatively easy to peel, or a thick molded material is scratched in the length direction at regular narrow intervals, and peeled parallel to the opposing surface 16. It is preferable to form portions 17... As a result, when the opposing surface 16 of the prevention material deteriorates due to heat after cutting the steel material, the opposing surface 16 can be removed by simply peeling off the deteriorated portion from the peeled portion 17.
6 becomes a new surface. Therefore, when the device is used next time, the excess portion will not adhere to the new facing surface and will not interfere with the function. Furthermore, the preventive material can be used effectively. As is clear from the above, according to the present invention, a preventer made of a preventive material facing the steel material is applied. The excess portion that flows out during fusing is guided to the preventer to prevent it from coming into contact with the surface of the steel material.

Therefore, there is no need to remove the excess portion from the steel material, and the excess portion attached to the preventer can be easily removed, making the fusing operation extremely efficient. In addition, when a long steel material is to be cut by fusing to a certain length, the steel material is moved to a certain length each time the steel material is cut by fusing. At this time, the steel material is heated by the previous cutting process, but according to the present invention, the heated steel material can be cut by applying a preventive tool to the surface, so that long steel materials can be cut continuously over a fixed length. It can also be used for fusing. Furthermore, since the preventive device is simply applied to the steel material, no scratch marks are left on the steel material, and the effect of preventing excess parts from adhering to the steel material is extremely high.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of the steel material during fusing, Fig. 2 is a longitudinal side view of the same as above, Fig. 3 is a perspective view of the steel material with a preventer applied, and Fig. 4 is a fusing with the preventer applied. FIG. 5 is a perspective view of another example of the preventer, and FIG. 6 is a perspective view of an example of the preventer.

Claims (1)

[Claims] 1. Apply a preventer consisting of at least a pair of left and right plate-shaped or rod-shaped preventive materials facing each other to the steel material so that the opposite edges of the preventive materials match the edges of the steel material's fusing range, and prevent the steel material flowing out during fusing. A method for fusing and cutting steel materials, characterized in that the excess portion is guided to the surface of the preventer to prevent it from adhering to the surface of the steel material.