JPH10138039A - High speed cutting method for pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate a burr and deformation by cutting of a round or square pipe having a large diameter by cutting the pipe under a specific cutting condition by using a high speed tip saw to rotate at specific peripheral speed and rotating speed in a traveling type pipe cutter to travel at specific line speed. SOLUTION: In a traveling type pipe cutter to travel at line speed of 0.1 to 100m/min when stainless steel hard round pipe and square pipe are cut, a high speed tip saw to rotate at peripheral speed of 700 to 1400m/min and rotating speed of 600 to 1300 mrpm is used. Cutting is performed so as to satisfy a cutting condition decided by cutting time T on which an expression is [T(sec)=t×M×Y] and the cut number on which an expression is [the cut number = 1/(T ×line speed)] besides a cutting condition where maximum feed speed is not more than 300mm/sec and a notch quantity per a single blade is 0.05 to 0.1mm. Here, in the expressions, (t) is a thickness of a cutting object pipe, and M is an outer periphery of the cutting object pipe, and Y is a cutting constant decided by a construction material of the cutting object pipe.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for cutting a pipe, and more particularly to a method for cutting a carbon steel pipe, a hard round pipe made of stainless steel, and a square pipe.

[0002]

2. Description of the Related Art Conventionally, as a method for cutting various pipes such as a round pipe and a square pipe, a grinding stone cutting method, a circular saw cutting method, and a press cutting method are known depending on a cutting device. For example, there are a cutting method using a disk cutter, a cutting method using a plasma, and a cutting method using a friction saw for cutting a square pipe. In these conventional methods, 1) since the outer diameter of the cutter decreases due to wear as the number of cuts increases, the cutter stroke must be adjusted, and the cutter life due to wear is short. 2)
Burrs affected by heat on the cut surface are stuck and it takes time to remove the burrs. 3) The pipe end is significantly deformed by a single action press, and the double action press requires two steps of cutting with a scratching blade and a cutting blade. It takes a lot of time to prepare for changing the cutting machine, and a mutual cutting device is required. 5) In plasma cutting, there are many problems such as a need to recut because the cut surface is rough.

Recently, a relatively high-speed cutting method using a milling cutter has been developed as a cutting method for solving the above-mentioned disadvantages. However, even with this method, burrs are small and the cut surface becomes beautiful. On the other hand, there is a problem that the cutting speed and the feed amount of the cutter cannot be large, and it takes time to cut, and furthermore, the size of the equipment has to be increased.

[0004] As an example, there is an apparatus described in JP-A-59-69212 and JP-A-59-69213. These apparatuses relate to a steel pipe cutting machine of a type that revolves around a pipe to be cut while rotating a milling cutter. However, in these devices, the rotating milling cutter swings and revolves, and the cutting feed of the cutter moves up and down by pushing the wedge at the end of the flange by pressing the inclined portion of the face plate, or swings the cutter head. Since cutting is performed with the center eccentric, the cutter drive motor is fixed, and the cutter is driven via the planetary gear, the size of the facility has to be increased as described above. Further, there is a problem that high-speed cutting cannot be performed in terms of the shape and material of the cutter, and that the cutting time is too long. Further, a steel pipe cutting apparatus disclosed in Japanese Patent Application Laid-Open No. 3-221311 has been developed. This device cuts the pipe by running in synchronization with the pipe making speed,
A plurality of cutter heads having a guide mechanism, a feed mechanism, and a milling cutter that linearly move in two axial directions (XY directions), and a clamp device that holds and fixes a pipe located near the milling cutter. A steel pipe cutting device which is provided on a traveling carriage and further includes a control device for controlling rotation of a feed drive motor of the cutter head based on input data of cutting conditions such as the shape and dimensions of the pipe. However, in the apparatus disclosed in this patent, the cutter head and the auxiliary equipment holding the cutter head need to be independently installed to secure rigidity in each of the X and Y directions, and the equipment scale becomes large. As a result, there is a problem that the cutting traveling speed is reduced.

[0005]

As described above, as a conventional traveling pipe cutting method, it is considered common practice to perform cutting at a cutter peripheral speed of 200 to 400 m / min using a milling cutter. And productivity was still low. In addition, cutting a hard material such as stainless steel at a high speed requires a longer time.

SUMMARY OF THE INVENTION The present invention provides a method for cutting a round or square pipe such as a stainless steel pipe at a high speed in a traveling type cutting machine.

[0007]

SUMMARY OF THE INVENTION The present inventors have studied various methods for cutting hard round pipes or hard square pipes such as carbon steel and stainless steel pipes at high speed in a traveling type cutting machine. Using a high-speed tip saw with a maximum speed of 2
A method was developed to cut 4-inch round or square pipes without cutting burrs, burns and deformation.

The gist of the present invention is that the line speed is 0.1 to 10
In a traveling type pipe cutting machine traveling at 0 m / min, the peripheral speed is 700 to 1400 m / min, and the rotation speed is 600 to
Use a high-speed tip saw rotating at 1300 rpm, and a maximum feed speed of 300 mm / sec or less, preferably 2 mm or less.
50 mm / sec or less;
A high-speed pipe cutting method for cutting under a cutting condition of 0.05 to 0.1 mm and a cutting time (T) and a number of cuts determined by the following formulas (1) and (2).

T (sec) = t × M × Y (1) where t = wall thickness of the pipe to be cut (mm) M = outer circumference of the pipe to be cut (mm) Y = depending on the material of the pipe to be cut Cutting constant determined

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The high-speed cutting method according to the present invention is generally used for cutting ordinary carbon steel pipes having a diameter of 24 inches or less or hard stainless steel pipes with a line speed of 0.1 to 0.1 mm. Assuming that the vehicle runs at 100 m / min, the peripheral speed of the conventional milling cutter is 200 to 400.
m / min, milling blade with outer diameter 300-400
mm, a high-speed tip saw that is embedded around a circular shape having a thickness of 2 to 3 mm and rotates at a rotation speed of 600 to 1300 rpm, and its peripheral speed is increased to 3 to 4 times 700 to 1400 m / mi.
n has a great advantage in cutting performance that the cutting speed is dramatically improved by greatly improving to n.
Pipe cutting machine feed speed up to 300mm / sec or less,
Preferably, the cutting load is 250 mm / sec or less, the cutting amount per blade is 0.05 to 0.1 mm, and the cutting time (T) is further reduced under the cutting conditions determined by the following formula. Compared with the milling cutter method of the above, can be greatly reduced to 1/3 or less.

Particularly important in the present invention are the cutting time and the number of cuts. When these values are in an appropriate range, high-speed cutting targeted by the present invention can be performed. That is, the cutting time is a value substantially proportional to the thickness of the pipe to be cut and the outer peripheral length of the pipe to be cut (pipe cutting area), and a cutting constant determined by the material of the pipe to be cut (1 for ordinary steel, 1 for stainless steel). .1 to 1.3,
Other high-strength steels and high-alloy steels: greatly influenced by a value obtained by multiplying three factors of 1.5). In any case, the cutting time T in the following equation is preferably 2 to 15 seconds / piece.

T (sec) = t × M × Y (1) In the above formula, t = wall thickness (mm) of the pipe to be cut is usually 0.5 to 30 mm, and M = cut pipe. Pipe circumference (m
m) is 80 mm to a maximum of 1914 mm since the pipe diameter that can be cut in the present invention is about 1 to 24 inches in diameter.
Further, in the present invention, the number of cuts of the pipe to be cut is an important factor in addition to the cutting time. This number of cuts can be expressed by the following equation (2).

[0013] That is, since it is the reciprocal of the cutting time T obtained by the above equation (1) multiplied by the cutting line speed, the smaller this value is, the higher the cutting efficiency is. Therefore, in the present invention, the number of cutting cuts is 5-2.
0 cut / min, preferably 8-12 cut / min
In the range, the value of the number of cuts decreases as the diameter increases from the small diameter to the large diameter.

Further, by employing the method according to the present invention, it is also possible to largely eliminate the stepped surface caused by the plurality of blades, which has been regarded as a major drawback in the conventional cutting method using a milling cutter.

[0015]

Embodiments of the present invention will be described below. In the present invention, when cutting round or square pipes, when cutting while running at a line speed of a cutter of 0.1 to 100 m / min, the diameter of the cut pipe and the number of cuts are important factors. Usually, the diameter of the pipe to be cut is about 3
The diameter varies from a small diameter to a large diameter of up to 24 inches, and how to cut at high speed corresponding to this diameter depends on the cutting time and the number of cuts. As expressed by the above two equations, the cutting time is 2 to 15 seconds, the number of cuts is 5 to 20 cuts / min, preferably 8 to 12 cuts / min. It is important to keep the number small.

Table 1 shows the cutting conditions of the SS41 ordinary steel pipe having an outer diameter of 10 inches and a wall thickness of 9 mm in the cutting method according to the present invention.

[0017]

[Table 1]

As described above, according to the method of the present invention, the outer diameter 1
In the case of a 0-inch ordinary steel pipe, the productivity is 5 to 6 in the case of the present invention, which is 30 to 50 in comparison with the conventional 3 to 4 pipes.
% And the cutting efficiency are remarkably improved.

[0019]

As described above, according to the present invention, it is possible to cut at high speed irrespective of ordinary carbon steel and stainless steel pipe, and to obtain a product with a beautiful cut surface with high productivity. .

Claims (1)

[Claims] 1. A traveling pipe cutting machine traveling at a line speed of 0.1 to 100 m / min.
1400m / min, rotation speed 600-1300mrpm
The cutting time (T) and the number of cuts are calculated using the following formulas, using a high-speed tip saw rotating at a speed of 300 mm / sec or less and a cutting amount per blade of 0.05 to 0.1 mm. A high-speed pipe cutting method, characterized in that the pipe is cut under cutting conditions determined in (1). T (sec) = t × M × Y (1) where t = wall thickness of the pipe to be cut (mm) M = outer circumference of the pipe to be cut (mm) Y = cutting constant determined by the material of the pipe to be cut