JPS6013579Y2 - plasma cutting equipment - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an apparatus for cutting steel pipes, which is equipped with a plurality of plasma torches (cutting torches).

Square steel pipes, rectangular steel pipes, and round steel pipes manufactured using conventional steel pipe manufacturing equipment, press equipment, or welded structures have closed cross-sectional shapes, so a saw cutter or a circular saw method such as a segment two is used as cutting equipment. It's here.

For example, in the former type of saw, a disk with saw-shaped teeth cut on the outer periphery is rotated at high speed by an electric motor, and the saw blade is sent by a hydraulic cylinder, etc., and this occurs when the saw blade comes into contact with the material to be cut. Cutting was performed using frictional heat.

This saw cutter can (1) cut objects with a closed cross section with a single disc;

(2) While it has the advantage of being able to cut at a high speed of up to 200 mm/sec, in view of the need to protect the working environment, which has become increasingly severe in recent years, the cutting noise can be as high as 120 to 130 dB. Even if you spend a lot of money installing soundproofing equipment, it still cannot completely solve the problem.

■ Molten iron powder scatters into the surrounding area, deteriorating the environment and posing a great danger to humans.

■ If the cutting conditions are not met, the saw blade will be damaged and there is a high risk of personal injury.

■ There were many problems, such as poor cutting quality such as residual debris left behind by the cutting, which not only required maintenance and labor in the post-process, but also frequent human accidents caused by the debris.

The latter type of segment saw has the same mechanical structure as a saw cutter, but the fact that a carbide tip is attached to the saw blade reduces the quality of the cut surface, noise, human danger, etc. Although it is superior to a saw in this respect, its biggest drawback is that the cutting speed is slow.

Therefore, by using multiple plasma cutting torches when cutting square steel pipes, rectangular steel pipes, or round steel pipes, (a) Even with multiple torches, the noise during cutting is about 85 to 95 decibels. Furthermore, since there is no contact between the blade and the material to be cut, unlike in conventional saw cutting machines, there is no resonance noise from the steel pipe, which is effective in reducing noise.

(b) By using multiple torches, the cutting speed is increased and the time required for cutting is shortened compared to a saw.

(c) Since no debris is left during cutting, maintenance in subsequent processes is simplified, and human disasters caused by debris can be solved.

It has many advantageous features such as:

The present invention provides a device for ensuring pilot arc ignition when operating four plasma cutting torches, and for preventing damage to the torch body and nozzle due to flying dross.

In detail, a protective cover is installed around the plasma torch to prevent instability of pilot arc ignition due to gas flow and damage to the torch body and nozzle due to flying dross during cutting, and to prevent maintenance during nozzle and electrode maintenance. The protective cover is screwed on and a quick-open method is used for easy installation.

The gist of this invention is to arrange a plurality of plasma torches with their injection ports facing the material to be cut, and to attach the plasma torches to a tracing device via a torch holder so that they can be moved freely along the cutting direction of the material to be cut. In addition, a protective cover mounting member is screwed onto the profiling device main body or the torch holder, and the protective cover is attached to the protective cover mounting member.

An embodiment of the present invention will be described below.

FIG. 1 is a front view showing an example of a case where four plasma torches are arranged to cut a square steel pipe as a material to be cut.

In FIG. 1, reference numeral 1 indicates a plasma torch, and four plasma torches 1 are arranged opposite to each other with their injection ports facing the cutting surface of a square steel pipe 19 as a material to be cut.

The plasma torch 1 can be raised and lowered by a cylinder 2.

3 is a roller holder, 4 is a roller, and 5 is a torch holder, and these 3, 4.5 constitute a tracing device 7 for the plasma torch 1.

The profiling device 7 sets a predetermined distance between the tip of the plasma torch 1 and the square steel pipe 19.

6 is a guide rod, 9 is a holder, and the holder 9
The cylinder 2 described above is connected to the holder 9.
is moved along the cut surface of the square steel pipe 9 by a screw connected to a drive device (not shown).

Therefore, in the present invention, the guide rod 6 and the holder 9
and the screw are collectively referred to as a moving device 8, and this moving device 8
It is also possible to use other means such as a self-propelled type or a cylinder.

2 and 3 show details of the device of the present invention, in which 10 indicates a protective cover mounting member (hereinafter referred to as mounting member 10), and 11 indicates a protective cover, respectively.

These installations are done using a notch 16 on the upper side of the protective cover 11.
The protective cover 11 can be attached to and removed from the attachment member 10 by means of a bolt fixed to the attachment member 10 that engages with the notch and a nut 12 that is screwed into the bolt.

In addition, in the present invention, the protective cover 11 is pivotally attached to the mounting member 10 with a rotating pin 13, and when maintenance is performed, the nut 12 is loosened and the protective cover 11 is rotated around the rotating pin 13, thereby allowing maintenance work to be carried out. Make it easy.

Further, the mounting member 10 is provided with a height adjustment elongated hole 14, and a bolt 15 is inserted into this height adjustment elongated hole 14, and the mounting member 10 is screwed onto the roller holder 3 portion of the tracing device 7.

In this case, the protective cover 1 is
The plasma torch 1 is completely protected by optimally setting the tip position of the torch 1.

Although FIGS. 2 and 3 show a mode in which the attachment member 10 is screwed onto the roller holder 3, it is also possible to attach it to the torch holder 5.

As shown in Fig. 4, in the present invention, when cutting a rectangular steel pipe, the four plasma torches 1 inject gas, e.g., air, at the same time as the pilot arc ignites. In this invention, the flow of air is allowed to escape as shown by arrow A using a protective cover, so that the pilot arc is not blown out by the flow of air in the lateral direction. Furthermore, since the scattering direction of the flying dross during cutting is also the same as the air injection direction, the protective cover 11 also protects the plasma torch 1 from the flying dross.

In the present invention, if the plasma torch is used in a place where there is air flow, air may be blown onto the pilot arc from all directions, so a protective cover 11 may be provided around the entire circumference of the plasma torch 1.

The effects of the present invention are as follows: (1) In the case of opposing plasma torches, the protective cover 11 enables reliable ignition of the pilot arc even if there is a flow of gas from other sources for the ignition of the pilot arc.

Therefore, even when the plasma cutting device is used on a so-called continuous line such as steel pipe manufacturing equipment, reliable cutting can be performed without stopping the line.

Furthermore, since unnecessary flashing of the pilot arc is eliminated, the life of the nozzle is extended, which is economical.

(2) Damage to the torch body or nozzle due to flying dross during cutting is also reduced, which is economically advantageous.

It is also advantageous when the plasma cutting device is used in a place where there is an air flow.

(3) The present invention also has advantages in terms of equipment, such as the ability to easily remove and install the protective cover and adjust its height.

[Brief explanation of drawings]

FIG. 1 is a front view of the plasma cutting device, FIG. 2 is a detailed front view of the device of the present invention, FIG. 3 is a three-dimensional perspective view of the protective cover of the present invention, and FIG. 4 is a conceptual front view of the device of the present invention. In the figure, 1 is a plasma torch, 2 is a cylinder, 3 is a roller holder, 4 is a roller, 5 is a torch holder, 7 is a tracing device, 6 is a guide rod, 9 is a holder, 8 is a moving device, 10 is a protective cover installation Components, 11 is a protective cover 12
13 is a nut, 13 is a rotating pin, 14 is an elongated bolt, 15 is a bolt, 16 is a notch, and 19 is a material to be cut.

Claims (1)

[Claim for Utility Model Registration] Four profiling devices are placed at each square of a rectangular workpiece, and each profiling device is movable in the same direction along a straight line of the workpiece. At the same time, attach a plasma torch to the profiling device with its jet nozzle facing the material to be cut via the torch holder, and screw the protective cover mounting member with the mounting hole on the roller holder or torch holder of the profiling device. A plasma cutting device characterized in that a protective cover is detachably screwed onto the protective cover mounting member.