JP5339000B1 - Cutting method of metal square tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cutting method for a metal rectangular tube which can perform horizontal cutting without hanging the cutting torch up and down and has excellent safety so that the fixing member and the torch do not fall after cutting. To do.
A step of horizontally attaching a long clamp 1 to a square pipe P by fastening both sides of the square pipe P with right and left clamping pieces; before or after attaching the long clamp 1 to the square pipe P A step of fixing the guide rail 2 in parallel to the long clamp 1; and after the long clamp 1 is attached to the square tube P, the cutting torch 3 is slidable with respect to the guide rail 2 fixed to the long clamp 1 Adopting the method including the step of attaching to
Further, when the cutting torch 3 is mounted on the guide rail 2, the gas discharge portion 31 of the cutting torch 3 is disposed on the lower side of the guide rail 2 and mounted in a state where the direction of the gas discharge portion 31 with respect to the rectangular tube material P is fixed. I tried to do it.
[Selection] Figure 1

Description

  The present invention improves the cutting method of a metal square tube, and more specifically, it can accurately perform horizontal cutting without hanging the cutting torch up and down, and it can make the operator fatigued even when working for a long time. In addition, the present invention relates to a cutting method for a metal square tube that is less likely to accumulate, and that is excellent in safety so that a fixing member and a torch do not fall after cutting.

  In general, for columns such as high-rise buildings that require higher load resistance than ordinary buildings, S structures that use large steel pipes as columns (structures that use steel pipes as they are hollow) and CFT structures (of steel pipes) A structure in which the hollow portion is filled with concrete is employed. In addition, square steel pipes having a square or rectangular cross-section are often used for the pillars of these buildings.

  On the other hand, when dismantling the building, it is necessary to cut and remove the large steel pipe constituting the pillar. In particular, the recently developed method of dismantling a high-rise building from the underside, such as dropping a harpoon, cannot remove a heavy load from the roof by hanging a large crane, so a large steel pipe can be carried by a small construction machine. It is necessary to divide it into sizes.

  So, in the past, gas cutting of the above large steel pipe was performed with the cutting torch in hand, but with that method, the torch is likely to shake up and down when moving the torch horizontally, so cutting must be performed accurately. Is difficult. Further, when cutting a square steel pipe, the cutting is not completed unless the positions of both ends of the cutting lines on each surface are matched, so that the working efficiency is likely to be lowered due to the shake of the torch.

  In addition, in gas cutting work for large steel pipes, the work must be continued with the torch height and orientation maintained constant. Become. Further, when the operator's concentration decreases due to accumulated fatigue, not only the work efficiency is lowered, but also a dangerous work mistake is caused.

  On the other hand, in the prior art, an annular guide rail is horizontally fixed around a large pipe arranged in the vertical direction, and a mounting table on which a welding torch is placed is slidably mounted on the guide rail (see Patent Document 1). ) Is also known, and in this technique, the shake of the torch can be suppressed by moving the torch on the mounting table.

  However, when the gas welding method described above, which uses a torch on a mounting table, is used for gas cutting, the upper side of the guide rail will be cut, so the steel pipe separated from the guide rail fixed to the lower side of the steel pipe after cutting Will fall with you. Also, if the torch is not held firmly by hand, it will fall together, which is very dangerous for the operator.

  On the other hand, in the prior art, a technique for fixing the guide rail to the plate material and sliding the cutting torch horizontally is also known (see Patent Document 2). However, in the guide rail fixing method described in this document, Since it takes time to attach the guide rail, it is difficult to efficiently cut a large steel pipe having many cut surfaces.

JP 2012-236221 A JP 2012-55917 A

  The present invention has been made in view of the above-described problems, and the object of the present invention is to accurately perform horizontal cutting without hanging the cutting torch up and down, and for a long time. It is an object of the present invention to provide a cutting method for a metal rectangular tube which is less likely to accumulate fatigue even when the work is performed, and which is excellent in safety so that a fixing member and a torch do not fall after cutting.

  Means employed by the present inventor to solve the above problems are as follows.

That is, the present invention is a method for cutting a metal square pipe P installed or supported in a vertical direction,
The rectangular tube material P is inserted between the holding pieces 12 and 12 of the long clamp 1 composed of a rod-like main body 11 and left and right holding pieces 12 and 12 slidably attached to the main body 11, and A step of horizontally attaching the long clamp 1 to the square pipe P by fastening both sides of the square pipe P with the right and left clamping pieces 12 and 12; a guide before or after attaching the long clamp 1 to the square pipe P; A step of fixing the rail 2 in parallel to the main body 11 of the long clamp 1; after the long clamp 1 is attached to the square tube P, a cutting torch 3 with respect to the guide rail 2 fixed to the long clamp 1 Adopting a method including a step of slidably mounting
Further, when the cutting torch 3 is mounted on the guide rail 2, the gas discharge portion 31 of the cutting torch 3 is disposed on the lower side of the guide rail 2 and mounted in a state where the direction of the gas discharge portion 31 with respect to the rectangular tube material P is fixed. There is a feature in the point made to do.

  Further, when removing the large rectangular tube P, the removing operation can be efficiently performed by sequentially cutting the rectangular tube P by a predetermined length from the lower side. Further, by attaching a level to the long clamp 1 or the guide rail 2, the cutting operation can be performed more accurately.

  In the present invention, a guide rail is fixed to a square steel pipe upright in the vertical direction through a clamp, and a cutting torch is slidably attached to the guide rail so that the cutting work of the square steel pipe is performed on the guide rail. Since the operation can be performed while keeping the vertical position and angle of the torch constant, the torch can be prevented from being shaken and an accurate cutting operation can be performed.

  In addition, if the torch is moved along the guide rail, when cutting each surface of the square steel pipe, the positions of both ends of the cutting line on each surface can be easily matched, so the cutting work of the square steel pipe is efficient. Can be done automatically. In addition, since the guide rail can be easily attached and detached by clamping, even a square steel pipe with many cut surfaces can be quickly operated.

  Moreover, in the present invention, since it is not necessary to work while holding the torch by hand, there is no worry that the worker will get tired even when working for a long time, and the worker keeps working without losing concentration. be able to. Furthermore, in the present invention, since the square steel pipe can be cut at a position lower than the fixed portion of the guide rail, the guide rail and the torch are not dropped together with the lower steel pipe immediately after the cutting is completed. .

  Therefore, according to the present invention, when removing a square steel pipe used as a pillar at the time of building demolition, the square steel pipe can be divided and removed efficiently, and the removal work can be performed safely. In addition, since a cutting method for a metal square tube material that can be used can be provided, the practical utility value of the present invention is very high.

It is a whole perspective view showing the instrument for cut | disconnecting the square tube material in Example 1 of this invention. It is a top view showing the state which attached only the elongate clamp and guide rail in Example 1 of this invention to the square tube material. It is a front view showing the state which attached only the long clamp and guide rail in Example 1 of this invention to the square tube material. It is a bottom view showing the state which attached only the elongate clamp and guide rail in Example 1 of this invention to the square tube material. It is X-X 'sectional drawing showing the state which attached only the elongate clamp and guide rail in Example 1 of this invention to the square tube material. It is a whole top view showing the state which attached the cutting torch to the guide rail in Example 1 of the present invention. It is a whole side view showing the state where the cutting torch was attached to the guide rail in Example 1 of the present invention. It is a state explanatory view showing the state where a square tube material is cut in Example 1 of the present invention.

“Example 1”
A first embodiment of the present invention will be described with reference to FIGS. In the figure, the reference numeral 1 indicates a long clamp, and the reference numeral 2 indicates a guide rail. What is indicated by reference numeral 3 is a cutting torch.

[About equipment to prepare]
In this Example 1, an instrument prepared in advance will be described. First, a long clamp 1 which can be fixed by sandwiching both sides of the rectangular tube P between the left and right clamping pieces 12 and 12 in a state where the rod-shaped main body 11 is arranged along one surface of the rectangular tube P installed in the vertical direction. A guide rail 2 is prepared which is fixed in parallel to the main body 11 of the long clamp 1 (see FIGS. 1 and 2).

  For the long clamp 1, a female screw hole H is provided at the tip of one clamping piece 12 in the same direction as the longitudinal direction of the main body 11, and a fastening bolt 12 a is attached to the female screw hole H. doing. Thereby, both sides of the rectangular tube material P can be easily tightened if the tightening bolt 12a at the tip of the sandwiching piece 12 is rotated by the handle 12b and tightened inward.

  Further, the holding pieces 12 and 12 of the long clamp 1 are slidably attached to the main body 11 and can be fixed at an arbitrary position of the main body 11 by a stopper 12c. Accordingly, as shown in FIGS. 3A and 3B, the gap between the sandwiching pieces 12 and 12 can be changed according to the thickness of the rectangular tube material P.

  On the other hand, with respect to the guide rail 2, V grooves 21 and 21 are provided on the upper and lower surfaces along the longitudinal direction, and a rack portion 22 is formed on the one side surface along the longitudinal direction. In this embodiment, as shown in FIG. 4, T-shaped spacers S, S,... For maintaining a constant distance from the square tube P are provided on the side surface of the guide rail 2 on the side where the rack portion 22 is not provided. It is attached.

  The guide rail 2 is fixed to the main body 11 of the long clamp 1 via L-shaped brackets B, B... As shown in FIG. In this embodiment, the upper part of the bracket B and the lower surface of the long clamp 1 are fixed by welding, and the lower part of the bracket B and the guide rail 2 are fixed by screws.

  On the other hand, in this embodiment, a cutting torch 3 that can be slidably mounted on the guide rail 2 is also prepared (see FIGS. 6 and 7). With respect to the cutting torch 3, the gas discharge portion 31 can be disposed below the long clamp 1 when mounted on the guide rail 2, and the direction of the gas discharge portion 31 with respect to the rectangular tube material P is constant. Select the one that can be fixed to.

  In the present embodiment, the cutting torch 3 is provided with two disk-like rotating bodies 32, 32, which run in the V grooves 21 and 21 of the guide rail 2 in accordance with the slide. ing. Further, by supporting the cutting torch 3 at four points by the rotating bodies 32, 32..., Vibration of the cutting torch 3 during use is suppressed, and the direction of the gas discharge portion 31 can be maintained constant.

  The cutting torch 3 is also provided with a gear 33 that moves while rotating on the rack portion 22 of the guide rail 2. And by increasing the load necessary for the movement of the cutting torch 3 with this gear 33, the problem that the cutting torch 3 moves more than necessary and the problem that the cutting torch 3 shakes to the left and right due to the load due to gas discharge are solved. it can.

[Rectangle tube cutting procedure]
Next, a procedure for cutting the rectangular tube material P using the above instrument will be described. First, as a first step, the rectangular pipe material P (in this embodiment, a steel pipe) is inserted between the holding pieces 12 and 12 of the long clamp 1 to which the guide rail 2 is fixed, and the left and right holding pieces 12 and 12 are inserted. Tighten both sides of the square tube P at 12 and attach the long clamp 1 to the square tube P horizontally.

  In the first step, the long clamp 1 can be fixed to the long clamp 1 after being attached to the square tube P. Further, if a leveling device is attached to the long clamp 1 or the guide rail 2, the attaching operation can be performed while confirming whether the long clamp 1 and the guide rail 2 are accurately fixed horizontally.

  Then, after the first step is completed, the cutting torch 3 is slidably mounted on the guide rail 2 as a second step. Specifically, the cutting torch 3 is attached to the guide rail 2 so that the upper and lower rotary bodies 32, 32... Of the cutting torch 3 are inserted into the upper and lower V grooves 21 and 21 of the guide rail 2.

  At this time, the cutting torch 3 is attached so that the gas discharge portion 31 is disposed below the guide rail 2 and the direction of the discharge portion 31 with respect to the rectangular tube material P is fixed. Thereafter, as a third step, as shown in FIGS. 8A and 8B, the cutting torch 3 is ignited, and the rectangular tube material P is cut while moving the cutting torch 3 horizontally from the end side.

  After the first to third steps are completed, the gas of the cutting torch 3 is stopped at one end, and the cutting torch 3 is removed from the guide rail 2 and the long clamp 1 is removed from the rectangular tube material P. Thereafter, the long clamp 1 is attached to the other surface of the rectangular tube P, and the same cutting is performed. This cutting operation is performed on all surfaces until the lower side of the rectangular tube P falls.

  In addition, when attaching the long clamp 1 to the other surface of the rectangular tube P, the position where the long clamp 1 is first attached is marked so that the positions of both ends of the cutting line on each surface coincide. Must be installed at the same height. Further, when removing the large rectangular tube material P, the rectangular tube material P is sequentially cut from the lower side by a predetermined length and removed.

  The present invention is generally configured as described above. However, the present invention is not limited to the embodiments, and various modifications can be made within the description of “Claims”. The pipe material P need not be a steel pipe, and may be a pipe material made of another metal material. Further, the rectangular pipe member P may be a duct or a pipe supported and fixed in the vertical direction.

  Further, the long clamp 1 only needs to have a structure in which the rectangular tube material P can be sandwiched and fixed by the left and right sandwiching pieces 12 and 12, for example, a structure in which the sandwiching pieces 12 and 12 are moved symmetrically by a ball screw is adopted. You can also. The fixing structure of the long clamp 1 and the guide rail 2 can also be fixed by a method other than welding or screwing.

  Furthermore, regarding the material of the long clamp 1 and the guide rail 2, a material other than metal can be used as long as it has a predetermined strength and is excellent in heat resistance. In addition, if the guide rail 2 and the cutting torch 3 are attached to each other as long as the cutting torch 3 can be moved on the guide rail 2, a general slider structure can be appropriately selected and employed.

  In addition, a slider member can be attached to the existing cutting torch 3 and mounted on the guide rail 2, and when cutting the rectangular tube material P, work is simultaneously performed on two opposing surfaces of the rectangular tube material P. The time taken to cut the entire circumferential surface can be reduced by half, and any of the above is within the technical scope of the present invention.

  In recent years, there are increasing opportunities to cut rectangular steel pipes used as pillar materials in dismantling construction of high-rise buildings, etc., but if the number of square steel pipes is large, the cutting work tends to be inefficient. Under such circumstances, the metal square tube cutting method of the present invention is a useful technique that not only can efficiently perform cutting work but also can ensure the safety of the worker, and thus has an industrial utility value. Is very expensive.

1 Long clamp
11 Body
12 Clamping part
12a Tightening bolt
12b handle
12c Stopper 2 Guide rail
21 V groove
22 Rack part 3 Cutting torch
31 Gas discharge part
32 Rotating body
33 Gear P Square tube H Female thread hole B Bracket S Spacer

Claims (3)

A cutting method of a metal square pipe (P) installed or supported and fixed in a vertical direction,
A clamping piece (12) (12) of a long clamp (1) comprising a rod-like body (11) and left and right clamping pieces (12) (12) slidably attached to the body (11) Insert the rectangular pipe (P) between them, and tighten both sides of the rectangular pipe (P) with the left and right clamping pieces (12) and (12), so that the long clamp (1) is horizontal to the square pipe (P). A step of fixing the guide rail (2 ) in parallel to the main body portion (11) of the long clamp (1) before or after the long clamp (1) is attached to the square tube (P). And attaching the cutting torch (3) to the guide rail (2) fixed to the long clamp (1) in a slidable manner after the long clamp (1) is attached to the rectangular tube (P). Including
Further, when the cutting torch (3) is mounted on the guide rail (2), the gas discharge part (31) of the cutting torch (3) is disposed on the lower side of the guide rail (2), and is attached to the rectangular pipe member (P). A metal square tube cutting method characterized by being mounted in a state in which the direction of the gas discharge part (31) is fixed.   The method for cutting a metal square pipe according to claim 1, wherein the square pipe (P) is cut in order from the lower side by a predetermined length.   The metal square tube cutting method according to claim 1 or 2, wherein a leveling device is attached to the long clamp (1) or the guide rail (2).