JP2543425Y2 - Crater - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fusing crater suitable for removing deep flaws at the corners of a steel material in a fusing operation performed as a flaw in a steel material.

[0002]

2. Description of the Related Art In a rolling process after casting of steel material, a so-called flaw cutting operation for removing so-called flaws such as cracks, pinholes, inclusions, etc. generated below the surface of the steel material such as slabs, blooms and billets is performed. In this case, the ends (corner corners) corresponding to the four corners of the steel material have a higher cooling rate than the outer peripheral portions of the other steel materials.
Cracks are likely to occur, and the depth of the cracks may reach up to about 7 to 10 mm.

[0003] Currently, the cutting operation is usually performed at a depth of about 1 to 3 mm from the surface of the steel material. It is necessary to perform abrasion or add only a corner. Therefore, while reducing the yield of steel materials, there is a problem in that the work efficiency is reduced and the cost is increased. In addition, a method for coping with this is considered, but the structure of the erosion crater and its apparatus are inevitably complicated, and the cost is increased.

[0004]

SUMMARY OF THE INVENTION The object of the present invention is to solve these problems of the prior art, and to efficiently remove deep cracks generated at the corners of a steel material and have a simple structure. Therefore, there is a need to provide a cutting crater that excels in workability.

[0005]

SUMMARY OF THE INVENTION For this reason, the cutting crater of the present invention has an upper unit having a heating fuel gas discharge hole and an upper shield oxygen discharge hole which are arranged vertically above and below a cutting oxygen discharge flow path. And a lower unit having a fuel gas ejection hole for heating, and in a cutting crater formed to correspond to the width of the steel material, at both ends of a cutting flow path of cutting oxygen,
It is slightly inclined so as to form an angle toward the tip from the entire cutting oxygen jetting flow path. In addition, a gentle slope is provided at the boundary between the two and the entire ejection flow path so as to be divergent with respect to the tip direction, so that the boundary is gentle.

[0006]

In the crater of the present invention, when the cutting oxygen is jetted through the jetting flow path of the cutting oxygen, the collision angle against the steel material at both ends of the jet flow strongly changes according to the change in the angle, and the Since the jet is directed to a location closer to the crater main body than the oxygen jetting direction line, the jet flow acts strongly, and the depth of the ablation becomes deep only at both corners. As a result, deep cracks and flaws can be completely removed.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS This embodiment will be described with reference to FIGS. FIG. 1 is a side view showing the whole of the present invention, and FIG.
FIG. 2 is a view taken along the line XX ′ in FIG. 1. FIGS. 3 (a) and 3 (b) show a cutting oxygen flow path (Y in FIG. 2) connecting the upper unit and the lower unit.
FIG. 3 is a perspective view of the display device, excluding each end wall, as viewed from a −Y ′ direction).

In FIG. 1, reference numeral 1 denotes an upper unit integrally formed with a shield block 1 ', and reference numeral 2 denotes a lower unit. Between the upper unit 1 and the lower unit 2, a blowing flow path 4 for cutting oxygen is formed on both sides with end walls 3, 3 ′ therebetween, and is connected to the head block 5. Reference numeral 6 denotes a shoe having a lower portion 6 'in contact with a steel material.

Numerals 7 and 8 denote a plurality of fuel gas holes arranged in parallel on the upper unit 1 and the lower unit 2 in parallel with the injection port of the cutting oxygen, and 9 denotes a plurality of fuel gas holes on the upper unit. Oxygen holes for a plurality of upper shields arranged in parallel with 7. 10 is this supply pipe.

[0010] 11 steel is scarfing, 12, 12 'has the same clearance t ₂ and the gap t ₁ of the ejection flow path 4 of the entire of scarfing oxygen, the scarfing oxygen with gentle slope toward the distal end As shown also in FIG. 3, the ejection flow paths on both ends of the ejection flow path are such that the ejection direction is directed to a location closer to the crater main body than the ejection direction of the main cutting oxygen flow path. That is, it is formed so that the angle stands toward the tip. 13, 13 'is the gap t ₃ of the ejection channel has a divergent inclined surface toward the tip t ₁
This is the boundary between the both ends and the main cutting oxygen dragon.
Reference numerals 13a, 13b and 13a ', 13b' denote boundary surfaces having the same angle in the upper and lower units, respectively, and 14 denotes a fuel gas inlet.

Next, an embodiment of the present invention will be described. The cutting crater of the present invention corresponding to the width of the steel material is set at a position as shown in FIG. 1, and the cutting is started. At this time,
The fuel gas is supplied from the fuel gas holes 7 and 8 to the injection port 4 of the cutting oxygen.
Blows out low-pressure oxygen to heat the steel surface. At the same time, oxygen for the upper shield is ejected from the oxygen holes 9 through the shield block 1 'to control the flow of the heating flame downward from above, and the heating effect is further increased by the addition of oxygen from above. Let it. The oxygen in the upper shield is used only at the start of the cutting.

After a few seconds, when the steel material reaches the ignition point, the oxygen pressure is increased from the injection oxygen jetting port 4 to eject oxygen to start the cutting operation. At this time, the steel material undergoes a melting and oxidation reaction, and accordingly, the abrasion proceeds.

This will be described with reference to the schematic diagram of the jet flow shown in FIG. 1. The relationship between the conventional jet flow of the cutting oxygen and the steel material is between AB and the present invention. Is ejected to the space between the CDs due to the influence of the inclination angles of both ends 12, 12 '.

The gap t ₁ of the ejection flow path and the gap t at the both ends.
₂ and the gap t _{3 at the} boundary are both in a relation of t ₁ = t ₂ = t ₃ , so that the cutting speed can be advanced with the same cutting strength without substantially changing the ejection speed and the oxygen flow rate of the ejection flow. ,
At both corners where the inclination angle is increased, the depth of the cutting becomes deeper by the amount of the strongly inclined inclination. For example, if the overall depth of the cut is 2.5 mm, a cut of about 8 mm can be made at the corner.

Furthermore, since the boundary between the upper unit and the lower unit that transitions to both end sides is formed gently with no step and a divergent inclined surface, the oxygen jet flow is A
The boundary of the machined surface at the corner at the transition from B to CD is also smooth, and there is no step-like streaking affecting post-processes.

[0016]

[Effects of the Invention] As described above, in the crater of the present invention, since only the corners of the steel material are automatically reinforced compared to the normal erosion work, the craters at the corners of the steel material are automatically strengthened. The generated deep cracks can be efficiently removed. Therefore, there are no disadvantages such as the conventional smelting crater and the accompanying equipment which are complicated and the cost is increased due to the increase in the number of processes, and the work can be easily performed to achieve the purpose. Is extremely large.

[Brief description of the drawings]

FIG. 1 is a side view, partially in section, of an embodiment of the present invention.

FIG. 2 is a view taken along the line XX ′ in FIG. 1;

FIG. 3 is a perspective view of the upper and lower units, excluding the end walls, as viewed from the YY ′ cutting oxygen flow path of FIG. 2;

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 upper unit 2 lower unit 3, 3 ′ endor 4 4 oxygen jet flow path 5 head block 6 shoe 7, 8 fuel gas hole 9 oxygen hole 10 supply pipe 11 steel material 12, 12 ′ both end sides of oxygen flow path 13, 13 ′ Border

Claims (1)

(57) [Scope of request for utility model registration] An erosion crater comprising: an upper unit having a fuel gas ejection hole and an upper shield ejection hole disposed with a cutting oxygen ejection passage interposed therebetween; and a lower unit having a fuel gas ejection hole. At both ends of the cutting flow path of the cutting oxygen, a gentle slope is provided toward the tip so that the direction of this blowing is set at the same gap as the entire discharge path, and transitions to both ends. A cutting crater suitable for removing deep flaws at corners of a steel material, characterized in that a sloping surface diverging toward the tip is provided at a boundary portion of the inner surface of the unit.