JP2521582Y2 - High pressure high speed cutting crater - Google Patents

Description

[Detailed description of the device]

[0001]

The present invention relates to a thick steel plate, for example, 200
The present invention relates to a high pressure and high speed cutting crater suitable for gas cutting a steel sheet having a thickness of up to 1000 mm.

[0002]

2. Description of the Related Art The present inventors have previously proposed a high-pressure high-speed cutting crater (Japanese Utility Model Publication No. 2-133525) as shown in FIG. 4 as a cutting crater for this kind of thick steel plate. This cutting crater encloses a high-speed cutting oxygen flow ejected from the central part of the crater, and a first heating flame is provided on the outside thereof, and a second heating flame is provided on the outside of the first heating flame. It is a gas cutting crater of a thick steel plate, and enhances the heating effect and the jet effect of the cutting oxygen gas stream by the synergistic effect of the heating by the second heating flame in addition to the first heating flame.

[0003]

According to the above-mentioned prior application, it was possible to obtain the intended action and effect, but when a thicker steel plate is targeted, the desired cutting speed and efficiency can be obtained with this cutting tip. Insufficient to achieve, and there was a demand for the development of a more effective cutting tip. The present invention has been made in response to such a request, and in order to increase the gas cutting speed of thicker steel plate and to increase the cutting efficiency, after further diligent experiments, the shape of the divergent portion of the cutting oxygen hole was changed. By adding the, the cutting speed can be increased, the quality of the cutting surface can be improved, and good cutting can be performed regardless of fluctuations in the cutting oxygen pressure.

[0004]

The gist of the present invention is to provide a sleeve for cutting oxygen jet and a cover for fixing the crater to the blow tube, and the sleeve is centered on the opening surface of the crater body. The heating oxygen jet port and the fuel gas jet port are concentrically bored and engraved alternately in the radial direction, respectively, and a cutting oxygen flow is generated by oxygen and fuel gas from the oxygen jet port and the fuel gas jet port. In a high-pressure high-speed cutting crater for thick steel plates of about 200 mm to 1000 mm, which is designed to form surrounding first and second heating flames, the throat diameter d of the divergent part through which the cutting oxygen flow passes is 3 to 5 mm.
In contrast, the throat length is d ~ 3d (mm), the divergence angle is 2
5 ° ± 10 °, and the diameter of straight part d ₁ that follows it
And its length are 1.6d to 1.9d (mm), respectively.
It is a high pressure, high speed cutting crater for thick steel plates characterized by having a diameter of 5d to 4d (mm).

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. Before that, a high-pressure and high-speed cutting crater proposed by the present inventors, which is a prerequisite structure of the present invention, will be described with reference to FIG. The cutting crater of FIG. 4 is composed of a crater body 1, a cover (also referred to as a crater stop nut) 2, and a sleeve 3 provided in the crater body 1 via a stop screw 4. Crater body 1
Is formed of a base portion 6 and inner and outer tubular bodies 7 and 8 respectively fastened to the screw portions thereof.

The cover 2 is loosely fitted so as to cover the outer periphery of the outer cylindrical body 8, and the engaging surface 9 of the base 6 is pushed up by using a screw carved on the outer periphery of the outer cylinder 8 for cutting corresponding to this cutting tip. It fits with the female screw of the blow pipe, and the taper surface 5 makes close contact with the blow pipe. The tip portion of the crater body 1 and the tip portion of the cover 2 are formed by slightly recessing the tip surface of the cover 2 into the X surface, the Y surface, and the Z surface, and gradually increasing the recesses toward the outside. The pits contribute to the mixing of heating oxygen and heating gas and the heating effect. The sleeve 3 which is inserted into the pore 1a penetrating in the longitudinal direction of the main body 1, contacts the inner circumference of the pore 1a at its tip, and is locked by the locking screw 4 at the base 1c, has a plurality of slits at the tip. 3a is engraved and serves as a passage for heating oxygen.

The cylindrical body 7 has a slit 7a formed in a protrusion contacting the inner circumference of the cylindrical body 8 to serve as a passage for heating gas.
Further, the plurality of through holes 7b indicated by broken lines are also heating gas passages. On the other hand, the through hole 7c communicates with the heating oxygen passage 1a,
The separated oxygen is placed between the fuel gas holes 7b as shown by 7c in FIG. 2, and oxygen is ejected from the holes to prevent the soot from adhering to the tip surface of the crater.

A plurality of heating oxygen passage holes 8a are formed near the outer peripheral portion of the distal end portion of the cylindrical body 8. Also, 7d, 8
Reference numeral b is a protrusion having a plurality of slits for suppressing the pulsation of heating gas and heating oxygen. In this cutting tip, the cutting oxygen flows in from the central through hole 11 and is jetted at supersonic velocity from the jet portion 14 via the throat 12 of the throat portion of the divergent portion and the divergent portion 13.

On the other hand, the oxygen for heating that has flowed in through the plurality of through holes 15 becomes oxygen for the first heating flame through the passages 1a and 3a and is ejected from the X surface, so that the plurality of fuel gas holes 16 are provided.
The fuel gas flowed in from is discharged from 7b through the passage 17 and merges with the oxygen to form a first heating flame surrounding the cutting oxygen flow. Further, the fuel gas ejected from the slit 7a through the passage 17 merges with the heating oxygen ejected through the plurality of through holes 18 and the passage 8a, and becomes a second heating flame, which surrounds the first heating flame. And then gush out. As a result, the first heating flame and the second heating flame exert a synergistic effect of the heating flame, enhance the heating effect, extend the heating flame, and further enhance the jet effect of the cutting oxygen stream.

The present invention relates to the improvement of this high-pressure and high-speed cutting crater, and improves the cutting speed and the cutting surface quality by making the shape of the diversent portion more effective as follows. And even if the cutting oxygen pressure fluctuates due to large consumption and is not affected by this,
A good cutting operation can always be maintained. The shape is shown in FIG. 3, and the experimental results are shown in Table 1.

Generally, in order to improve the gas cutting efficiency,
A divergent type cutting tip is used, particularly a tapered divergent type cutting tip for ease of manufacturing. At the cutting tip of this diversent, a throat section and a diverging section that follows the throat section are provided in the path of the cutting oxygen (see Fig. 4), and the oxygen flow accelerated to the speed of sound at the throat section is further accelerated in the diverging section. By doing so, the cutting oxygen flow ejected from the crater is made supersonic, the energy loss of the cutting oxygen is suppressed, and the cutting speed is improved.

Conventionally, in gas cutting a thick steel plate of about 200 mm to 1000 mm, a divergence angle of 3.3 to 6.5 mm and a divergence angle (often represented by a divergence ratio, but here represented by a divergence angle) 4 °. In contrast to the case of ~ 12 °, in the present invention, as shown in FIG. 3, the throat diameter d =
3 to 5 mm, and throat length L ₁ = d to 3 d
(mm), divergence angle θ = 25 ° ± 10 °, and subsequent straight portion diameter d ₁ = 1.6d to 1.9d (mm),
The straight portion length L _{2 is} 2.5 d to 4 d (mm).

The above-mentioned throat portion diameter d and throat length L ₁ are within a range that can sufficiently correspond to the target thick steel plate, and the divergence angle θ, straight portion aperture d ₁ , straight portion length L ₂ Regarding, regarding below the lower limit of each stipulated range, no improvement can be seen without changing from the result of cutting by the conventional crater, and above the upper limit, turbulence of the cutting oxygen flow, reduction of cutting speed and deterioration of cut surface quality can be seen. Therefore, it is necessary to maintain the above range.

As described above, since the straight portion 10 is provided following the throat portion 12 and the divergent portion 13, the flow of the cutting oxygen gas flow is stabilized, and as shown in Table 1, the cutting speed is higher than that of the conventional one. As shown by comparing the cross sections of the conventional method (a) and the present invention (b) of FIG. 5 with 15 to 20% improvement, the quality of the cut surface can be improved.

Furthermore, even if the cutting oxygen pressure is reduced to about ² to 3 kgf / cm ² due to the decrease of the supply oxygen consumed in a large amount, at the cutting tip, the cutting oxygen pressure is 7 to 20 kgf /
Since stable gas cutting can be performed in the cm ² range, there is no hindrance to work, and it is not necessary to monitor the error range of ± 1 kgf / cm ² unlike the conventional diversent type cutting crater.

[0016]

[Table 1]

[0017]

As described above, according to the cutting tip of the present invention, it can be applied to thick steel plates at a higher cutting speed and stable cutting work can be performed. The cutting work efficiency and quality can be improved, and it greatly contributes to the gas cutting work.

[Brief description of drawings]

FIG. 1 is a partially sectional front view showing an embodiment of the present invention.

FIG. 2 is a view taken along the line AA ′ of FIG.

FIG. 3 is a view showing a diversent part of the present invention.

FIG. 4 is a partially sectional front view of a conventional high-pressure high-speed cutting crater.

FIG. 5 is a cross-sectional view of a cut surface of a steel plate, in which (a) is conventional means and (b) is cutting by the present invention.

[Explanation of symbols]

1 Crater body 2 Cover 3 Sleeve 4 Stop screw 5 Tapered surface 6 Main body base 7,8 Cylindrical body 7a Heating gas slit 7b Heating gas through hole 7c Oxygen through hole 8a Heating oxygen through hole 7d, 8b Protrusion 9 Locking surface 10 Straight part 11 Central through hole 12 Throat 13 End widened part 14 Jet part 15 Oxygen through hole 16 Fuel gas hole 17 Fuel gas passage

Claims (1)

(57) [Scope of utility model registration request] 1. A sleeve for ejecting cutting oxygen and a cover for fixing a crater to a blow tube. The sleeve is centered on the opening surface of the crater body, and an oxygen outlet for heating and a fuel gas outlet are provided. , Piercing and engraving concentrically in the radial direction alternately, forming first and second heating flames surrounding the cutting oxygen stream by the oxygen and the fuel gas from the oxygen jet port and the fuel gas jet port. 200mm ~ 100
In a high pressure and high speed cutting tip for thick steel plate of about 0 mm, the throat diameter d of the divergent portion through which the cutting oxygen flow passes
For 3 to 5 mm, the throat length is d to 3 d (mm), the divergence angle is 25 ° ± 10 °, and the subsequent straight portion caliber d ₁ and its length are 1.6 d to 1.9 d (m), respectively.
m), 2.5d-4d (mm), a high-pressure high-speed cutting crater for thick steel plates.