JPH10314949A - Pipe cutting equipment - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To cut with high accuracy, high efficiency, safe and small space. SOLUTION: A clamp mechanism 1 for fixing a moving steel pipe 2, a plasma torch 3 arranged on the outer circumference of the steel pipe 2 fixed by the clamp mechanism 1, and air for pushing the plasma torch 3 in the outer circumferential direction of the steel pipe 2. A cylinder 4, a rotating mechanism 5 for moving the plasma torch 3 pushed by the air cylinder 4 in the outer peripheral direction of the steel tube 2 along the outer periphery of the steel tube 2, a plasma torch 3 pushed by the air cylinder 4, and the steel tube 2 The structure includes a guide mechanism 6 for smoothly moving the plasma torch 3 while keeping a constant distance from the outer periphery of the steel pipe 2, and a tuning movement mechanism 7 for moving in synchronization with the steel pipe 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for cutting, for example, a steel pipe or a square pipe having a relatively smooth sectional shape.

[0002]

2. Description of the Related Art For example, when cutting a steel pipe at a fixed position, a cutting tool, a saw, a rotary blade, a gas or a plasma torch is used. Of these, a cutting tool using a cutting tool can only cut a steel pipe having a very small diameter. Or, at the time of cutting, the steel pipe is easily crushed and its cross section is easily deformed. Further, when a saw is used, the deformation of the cross section at the time of cutting is small and cutting can be performed with high accuracy, but the time required for cutting is long, and the working efficiency is poor.
In addition, when a rotary blade is used, there is little deformation of the cross section at the time of cutting, accurate cutting is possible, and the time required for cutting is short, but since the cutting thickness is small and the tool life is short, When large diameter steel pipes are cut from large diameter steel pipes, large equipment is required, and large space and equipment investment are required. Further, when a gas or a plasma torch is used, the cross-sectional deformation at the time of cutting is smaller and the time required for cutting is shorter than when the above-mentioned blade or the like is used, but the cutting accuracy is poor.

Therefore, various proposals have been made for cutting at a fixed position. For example, JP-A-61-
No. 172,676 discloses cutting using a plasma arc, and JP-A-2-256715 discloses a cutting using a plasma torch.
No. 34056 proposes a cutting method using an oxygen acetylene torch.

[0004] On the other hand, when cutting a steel pipe while traveling, a rotary blade is generally used. However, it is necessary to synchronize the rotary blade with a high-speed line speed with high accuracy, so that a very large facility is required. Requires large space and capital investment. In addition, since the cut part when the line is stopped becomes scrap, it is generally removed manually by using a gas torch, etc.However, it is dangerous work, and if the cut surface is too bad, the downstream equipment will be damaged and the product will be damaged. Since there is a possibility that a defect may occur, it is necessary to stop the line immediately after cutting and to extract several tens of meters to make scrap.

Therefore, a guide mechanism that linearly moves in two axial directions, a plurality of cutter heads having a feed mechanism and a steel pipe clamping mechanism are provided on a traveling carriage, and input data of cutting conditions such as the shape and dimensions of the pipe are provided. Japanese Patent Application Laid-Open No. 3-221313 proposes a device provided with a control device for controlling the rotation of a feed drive motor of a cutter head based on the above.

[0006]

However, when cutting at a fixed position, the method proposed in Japanese Patent Application Laid-Open No. 61-172676 requires rotation of the steel pipe itself, so that the steel pipe itself cannot be rotated. Can not be adopted in the case of. Further, what is proposed in Japanese Patent Application Laid-Open No. 2-256715 must be a large-diameter steel pipe capable of suspending the apparatus inside a steel pipe to be cut. Also,
Japanese Patent Application Laid-Open No. S48-34056 uses a gas torch, so that the cutting width is larger than that of a plasma torch. Therefore, when cutting the lower surface of the steel pipe, the torch is easily damaged by the fall of the slag, and the cutting speed is as low as about 1/2. In addition, cutting gas and oxygen are required for cutting, and a plurality of hoses are required for the supply.Because a bevel table is used to fix the steel pipe, it takes time to set the piping position. Hangs.

[0007] Further, when traveling and cutting, Japanese Unexamined Patent Publication No. 3-221
The one proposed in No. 311 uses a milling cutter to improve the cutting speed by about 1.5 times as compared with the one using a conventional rotary blade, but it still cuts compared to the one using a plasma torch. Since the speed is 1/5, a long cutting distance is required for traveling cutting. Further, when cutting the hot steel pipe, the steel pipe may be crushed.

The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to provide a pipe cutting device which can cut a pipe with high accuracy, high efficiency, safety and small space. .

[0009]

In order to achieve the above-mentioned object, a pipe cutting apparatus according to the present invention is arranged so that a cutting torch arranged on the outer circumference of a pipe is pushed along the outer circumference of the pipe while being pushed in the outer circumferential direction of the pipe. And move it. In this way, the pipe can be cut with high accuracy and high efficiency in a safe and small space.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A pipe cutting apparatus according to the present invention includes a cutting torch disposed on the outer circumference of a pipe, a pressing mechanism for pushing the cutting torch in the outer circumference of the pipe, and a pressing mechanism for pressing the cutting torch in the outer circumference of the pipe. A rotating mechanism for moving the cutting torch pressed along the outer circumference of the pipe, and a smooth movement of the cutting torch while maintaining a constant distance between the cutting torch pressed by the pressing mechanism and the outer circumference of the pipe. It is provided with a guide mechanism, and if necessary, a clamp mechanism for fixing the pipe is provided, and a synchronized moving mechanism is installed so as to be able to move in synchronization with the moving steel pipe.

In the tube cutting apparatus according to the present invention, the cutting torch to be used is not limited to the plasma torch but may be a gas torch as long as it can cut the tube. However, when a plasma torch is used, the cutting time can be shortened because the cutting speed is two to three times faster than when a gas torch is used. Also, the width of the cut is 1/2 to 1/3
This has the advantage that the amount of slag is small, the surface shape around the cut surface is good, and only one cable is required.

Further, in the pipe cutting apparatus according to the present invention, the number of cutting torches to be installed is not particularly limited. However, when a plasma torch is used as the cutting torch, the above-mentioned advantages are obtained. By arranging three plasma torches at equiangular positions, the cutting time can be reduced.

Further, in the pipe cutting apparatus according to the present invention, the pressing mechanism is not particularly limited, and a spring, a screw, a hydraulic cylinder, or the like can be used. Adopt an air cylinder that can follow even if the center of the supported tube is slightly out of order, and can cut any size tube within the stroke even if there is no dimensional information of the tube. It is desirable.

In addition, it is necessary to maintain a certain interval between the cutting torch and the pipe in order to blow the initial spark, and therefore, the pipe cutting device according to the present invention requires a guide mechanism. . Therefore, any configuration may be used as long as the above-mentioned object can be achieved.However, if a non-contact type sensor or the like is used, it tends to be expensive, so that a flaw is formed on the outer peripheral surface of the tube. It is desirable to use a roller that can reliably maintain the spark distance.

In the tube cutting device according to the present invention, the tuning movement mechanism is not particularly limited as long as the movement of the cutting device can be synchronized with the moving speed of the tube. For example, a mechanism having a fixed speed at the mechanism side may be used. However, in order to perform cutting with high precision, it is desirable to control the tuning speed signal by feeding back the tuning speed signal from the drive motor and the tube itself using a servomotor or the like.

In the pipe cutting apparatus according to the present invention, the cutting torch disposed on the outer circumference of the pipe is held by the pressing mechanism in a state in which the distance between the cutting torch and the outer circumference of the pipe is kept constant by the guide mechanism. The pipe is cut by being moved along the outer circumference of the pipe by a rotation mechanism while holding the pipe. Then, when the tube is cut by using a clamp mechanism to clamp the tube, the cut cross section becomes good. In addition, if a synchronous movement mechanism is provided, even a moving steel pipe can be cut.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A pipe cutting apparatus according to the present invention will be described below with reference to an embodiment shown in FIGS. 1 is a front view showing the entire pipe cutting apparatus according to the present invention, FIG. 2 is a side view of FIG. 1, FIG. 3 is a plan view of FIG. 1, and FIG. 4 is an explanatory view of a cutting torch and a rotating mechanism in FIG. FIG. 5 is an enlarged explanatory view of a main part of the rotating mechanism, FIG. 6 is a sectional view seen from the side of FIG. 5, and an enlarged sectional view at the tip of the plasma torch.

1 to 7 are installed between a heating furnace of a continuous hot pipe making facility and a facility for narrowing down a main pipe to a specified size, for example, a pipe diameter of 90 to 140 mm and a wall thickness of 3 to 3 mm. 9m
m is a diagram showing a pipe cutting apparatus according to the present invention for cutting a cold steel pipe main pipe at room temperature or a hot steel pipe main pipe at 1000 ° C. (hereinafter, these are simply referred to as “steel pipes”). It is such a configuration.

In FIGS. 1 to 7, reference numeral 1 denotes a clamp mechanism for fixing a steel pipe 2. The clamp mechanism 1 is, for example, as shown in FIG.
air cylinders 1c and 1d in the middle of each of a and 1b
Air cylinders 1c and 1d
Of the pair of arms 1a, 1b is moved in synchronism by the action of the tuning gears 1e, 1f installed at the one-end side pivotal support of the arms 1a, 1b. , To fix the steel pipe 2 in a sandwiched manner. In addition, considering that this clamp mechanism 1 improves the cut surface,
It is desirable that the steel pipe 2 be provided. However, in the case of a hot material, the steel pipe 2 may be crushed at the time of fixing.

Reference numeral 3 denotes a plasma torch disposed at the outer periphery of the steel pipe 2 fixed by, for example, the clamp mechanism 1 at the time of cutting. For example, as shown in FIG. Are arranged at an angle of 120 °. Each of these plasma torches 3 is configured to move toward and away from the outer periphery of the steel pipe 2 by a pressing mechanism, for example, a rod of an air cylinder 4 moving out and back. By the way, as shown in FIG. 7, in this embodiment, the plasma torch 3 is viewed from the tip of the torch in order to protect the plasma torch 3 from heat and to prevent the life of the torch tip from being shortened by spatter or water. As shown by an arrow in FIG. 7, an air blow-out structure is employed.

Reference numeral 5 denotes a rotation mechanism of the plasma torch 3, for example, as shown in FIGS. 4 to 6, for forward and reverse rotation of the output shaft of a motor 5a with a speed reducer via a sprocket 5b, a chain 5c and a sprocket 5d. And sprocket 5d
And a ring gear 5f meshing with the pinion 5e is rotated by the guide of a guide roller 5g. The rotation of the ring gear 5f rotates the plasma torch 3 and the air cylinder 4, which are integrally attached to the ring gear 5f.

Reference numeral 6 denotes a guide mechanism for smoothly moving the plasma torch 3 while maintaining a constant distance between the plasma torch 3 and the outer periphery of the steel pipe 2. In this embodiment, a swing type roller is disclosed. I have.

Reference numeral 7 denotes a synchronous moving mechanism for moving the clamp mechanism 1, the plasma torch 3, the air cylinder 4, the rotating mechanism 5 and the guide mechanism 6 in synchronism with the steel pipe 2, and is provided on the transfer line of the steel pipe 2. A traveling carriage 7a provided with each of the mechanisms 1, 3 to 6 described above is tuned on the frame 8 by a servomotor 7b mounted on the traveling carriage 7a. And the servo motor 7
In this embodiment, as the transmission mechanism for the forward and reverse rotation of the output shaft b, in the present embodiment, the forward and reverse rotation of the output shaft of the servo motor 7b is carried out via the sprocket 7c, the chain 7d, and the sprocket 7e. 7f, and a pinion 7g externally fitted to the rotating shaft 7f is meshed with a rack 8a laid on the frame 8 to thereby provide a traveling cart 7a.
Are disclosed.

In FIG. 4, reference numeral 11 denotes an air cylinder. When the rod is extended and retracted, the pipe cutting device is connected to a steel pipe so that the tube cutting device according to the present invention can be retracted when not cut. 2 is moved toward and away from the object 2.

1 to 6, reference numeral 9 denotes a steel pipe 2 of the plasma torch 3 due to the reciprocation of the rod of the air cylinder 4.
A guide rod for smoothly moving the carriage 7a, a guide roller for smoothly moving the carriage 7a, a wrapper guide 12 and
Indicates a kicker for kicking out the steel pipe 2 after cutting.

The pipe cutting device according to the present invention has the above-described configuration. Next, a method of cutting a running steel pipe using the cutting device will be described. First, when it is necessary to cut while running when the line is stopped, the servo motor 7b receives a speed signal from a speed measuring device for the steel pipe 2 disposed downstream of the pipe cutting device, and synchronizes with the moving speed of the steel pipe 2. The traveling carriage 7a is moved, and the steel pipe 2 is fixed by the clamp mechanism 1.

Then, the plasma torch 3 arranged on the outer periphery of the steel pipe 2 fixed by the clamp mechanism 1 is pressed toward the outer periphery of the steel pipe 2 by the projecting operation of the rod of the air cylinder 4. At this time, the gap between the plasma torch 3 and the outer periphery of the steel pipe 2 is kept constant by the guide mechanism 6. The steel pipe 2 is cut by moving the plasma torch 3 along the outer circumference of the steel pipe 2 by the rotation mechanism 5 in the above-described state.

By the way, if the above-described pipe cutting device according to the present invention is used, a good cutting surface can be cut at substantially the same speed (2400 mm / min) as when a conventional rotary blade (single blade) is used. It is possible to cut with a small moving distance (1300 mm) at the time of cutting while running.

In this embodiment, a device capable of cutting while running provided with the clamp mechanism 1 and the synchronous moving mechanism 7 is disclosed. However, the present invention is not limited to this. The clamp mechanism 1 need not be provided. Further, if the fixed steel pipe 2 is to be cut, the synchronization moving mechanism 7 is not required.

[0030]

As described above, according to the pipe cutting apparatus of the present invention, the process from setting to cutting can be performed automatically, so that the pipe can be cut safely, in a small space, with high accuracy and high efficiency. can do.

[Brief description of the drawings]

FIG. 1 is a front view showing an entire pipe cutting apparatus according to the present invention.

FIG. 2 is a side view of FIG.

FIG. 3 is a plan view of FIG. 1;

FIG. 4 is an explanatory diagram of a cutting torch and a rotation mechanism in FIG. 1;

FIG. 5 is an enlarged explanatory view of a main part of a rotation mechanism.

FIG. 6 is a cross-sectional view as viewed from a side direction of FIG. 5;

FIG. 7 is an enlarged cross-sectional view of a tip portion of the plasma torch.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Clamp mechanism 2 Steel pipe 3 Plasma torch 4 Air cylinder 5 Rotation mechanism 6 Guide mechanism

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Shigeru Mizui 3 Oji Hikari, Kashima City, Ibaraki Prefecture Sumitomo Metal Industries, Ltd. Kashima Works, Ltd. (72) Inventor Yasuhiro Ezaki 1-22 Kawaramachi, Kashiwara-shi, Osaka Kashiwabara, Inc. Inside Machine Works (72) Inventor Kazuichi Yamada 1-22 Kawaramachi, Kashiwara City, Osaka Prefecture Inside Kashiwara Machine Works, Ltd.

Claims (3)

[Claims] 1. A cutting torch disposed on the outer periphery of a pipe, a pressing mechanism for pressing the cutting torch in the outer peripheral direction of the pipe, and a cutting torch pressed in the outer peripheral direction of the pipe by the pressing mechanism. And a guide mechanism for smoothly moving the cutting torch while maintaining a constant distance between the cutting torch pressed by the pressing mechanism and the outer periphery of the pipe. Cutting device. 2. The tube cutting device according to claim 1, further comprising a clamp mechanism for fixing the tube. 3. The pipe cutting device according to claim 1, further comprising a synchronous moving mechanism provided to move in synchronization with the moving steel pipe.