JP2001232514A - Groove cutting device for metal tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a groove cutting device that is convenient for carrying and facilitates a field work. SOLUTION: A pair of frames 1, 2 for grabbing a side surface of a metal tube 7 are interconnected through an interval adjusting means 6, and the inner surfaces of the frames 1, 2 have a rotation roller 8 in one or both of circumferential directions of the metal tube 7 while abutting on the inner surface of the metal tube 7. A rotation motor 9 is mounted to one frame 1, and a rotation blade 11 allowing edge preparation that rotates in the cross sectional direction of the metal tube 7 is mounted to the rotation motor 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides an apparatus for cutting a metal pipe, which is convenient to carry and can easily cut a metal pipe such as a gas steel pipe on site.

[0002]

2. Description of the Related Art Conventionally, an apparatus for cutting a metal pipe such as a gas steel pipe by a groove has a structure in which a large base is provided with a rotary blade.

[0003]

However, such a conventional technique is inconvenient to carry because of the large size of the apparatus, and is not suitable for work on site.

The present invention has been made by paying attention to such a conventional technique, and provides an apparatus which is convenient to carry and can easily cut a groove of a metal pipe on site.

[0005]

According to the first aspect of the present invention,
A pair of frames that sandwich the side surface of the metal tube are connected by a gap adjusting means, and the inner surface of the frame has a rotating roller that rotates in one or both directions in the circumferential direction of the metal tube in contact with the inner surface of the metal tube. A rotary motor was attached to one of the frames, and a rotary blade capable of beveling and rotating along the cross-sectional direction of the metal tube was attached to the rotary motor.

According to the first aspect of the present invention, the structure is such that the rotary motor is mounted on a pair of frames whose distance can be adjusted, so that the structure is simple and convenient to carry. Further, since the interval between the frames can be adjusted, it is possible to cope with metal pipes having different diameters. In addition, the work is easy because the frame is rotated, and the bevel cutting is accurate because the rotating roller rotates in the circumferential direction of the metal tube. When the rotating blade is moved along the circumferential direction, it is always cut. Return to the starting point. In addition, since the rotary motor is mounted on the frame, a commercially available rotary motor (tool) can be used, which is advantageous in terms of cost and maintenance.

In the invention according to claim 2, a handle portion is provided at one end of the frame.

According to the second aspect of the present invention, since the handle is provided at one end of the frame, the holding of the device is ensured and the work is easy to perform.

According to a third aspect of the present invention, the rotating roller is rotatable in only one direction in the circumferential direction of the metal tube and is not rotatable in the other direction, and the direction in which the rotating roller cannot rotate is reversed with respect to the rotating direction of the rotary blade. Direction.

According to the third aspect of the present invention, even if the rotary blade cuts into the metal tube and stops rotating, the rotating roller does not allow the frame to rotate in the reverse direction, so that the worker is not swung. Only

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described below with reference to FIGS. Reference numerals 1 and 2 denote a pair of frames, each having a handle portion 3 on the upper surface.
Two guide shafts 4 extend from the upper part of one frame 1, and these two guide shafts 4 pass through the upper part of the other frame 2. Also, one frame 1
A screw shaft 6 is provided between the two guide shafts 4 as a "spacing means" rotatable by a handle 5 (see FIG. 4). The tip of the screw shaft 6 is connected to the other frame. 2 is screwed to the upper part. Accordingly, the distance between the pair of frames 1 and 2 can be adjusted by turning the handle 5 of the screw shaft 6. In the frames 1 and 2 of this embodiment, a gas steel pipe (metal pipe) 7 having a diameter of 100 to 200 mm can be sandwiched.

The lower surface of each of the frames 1 and 2 has an inner surface recessed so as to sandwich the gas steel pipe 7, and a pair of upper and lower generally cylindrical rotating rollers 8 is provided on the inner surface. The rotating roller 8 can rotate only in the direction indicated by the arrow A in FIG. 2, but cannot rotate in the opposite direction. This rotating action in only a certain direction can be obtained by using a known ratchet mechanism or the like. And this rotating roller 8 is arranged horizontally,
It rotates only in the one direction A along the circumferential direction of the gas steel pipe 7, and does not move obliquely along the circumferential direction. Therefore, if the rotating roller 8 makes a round around the gas steel pipe 7, it always returns to the starting position accurately.

A rotary motor 9 is mounted on the side of one frame 1. The rotary motor 9 is a main body of a commercially available grinder, and the rotary motor 9 is attached with a metal fitting. The rotating shaft of the rotating motor 9 is covered with a dedicated cover 10, and a dedicated rotating blade 11 is mounted inside instead of the grinder blade. Rotary blade 1
1 rotates in the direction indicated by the arrow B in FIG. 2 along the cross-sectional direction of the gas steel pipe 7. By turning another handle 12, the entire rotary motor 9 can be brought into and out of contact with the gas steel pipe 7. . Also, by turning a knob (not shown),
The cutting depth by the rotary blade 11 can be finely adjusted.
A “scale” indicating the position of the rotary motor 9 with respect to the frame 1 may be provided, and the depth of cutting by the rotary blade 11 may be managed by the scale.

The rotary blade 11 has a three-piece structure in which a side blade 14 for groove is overlapped on both sides of a center blade 13 for cutting, respectively (see FIG. 3). Therefore, at the same time as the gas steel pipe 7 is cut, the cut end face can be subjected to a groove processing of about 30 °. Therefore, the gas steel pipe 7 subjected to this groove processing
If the cut ends of the butt abut each other, a V groove of about 60 °
The reliable welding can be performed there.

Next, the procedure for actually cutting the groove of the gas steel pipe 7 will be described. First, at the site, the gas steel pipe 7 is placed on a table or the like, and is fixed by stepping on the foot. Next, the frames 1 and 2 of the apparatus are widely opened and set on the gas steel pipe 7. After setting, the cutting edge of the rotary blade 11 is adjusted to the groove cutting position, and the rotating roller 8 is pressed against the gas steel pipe 7 by turning the handle 5. Next, after rotating the rotating blade 11, another handle 12 is turned to rotate the rotating blade 11
Of the cutting edge (working point) to a predetermined depth. Next, holding the handles 3 of the frames 1 and 2 and cutting the entirety in the cutting traveling direction C
(See FIG. 2), the gas steel pipe 7 is cut slowly.

Even if the rotary blade 11 bites into the gas steel pipe 7 and stops, the frames 1 and 2 do not swing in the reverse direction. This is because, as described above, the rotating roller 8 can rotate only in the direction A along the cutting traveling direction C, and cannot rotate in the reverse direction. Therefore, operational safety is maintained.

Since the rotating roller 8 rotates only in the circumferential direction of the gas steel pipe 7, when the rotary blade 11 is moved along the circumferential direction of the gas steel pipe 7, the rotary blade 8 always returns to the starting point of cutting, and accurate groove cutting is performed. I can do it. The cut end face of the gas steel pipe 7 is beveled obliquely in accordance with the shape of the cutting edge of the rotary blade 11, so that the subsequent welding operation can be reliably performed.

And above all, according to this embodiment,
The device is compact and convenient to carry, and the work is easy because the frames 1 and 2 are rotated.
Further, since a commercially available rotary motor (tool) 9 can be used, it is advantageous in terms of cost and maintenance.

In this embodiment, the gas steel pipe 7 is used as an example of the metal pipe, but the present invention is not limited to this. In addition, the metal pipe that can be cut and cut has a diameter of 100 to 200 mm as an example, but is not limited to this range.

[0020]

The bevel cutting device for metal pipes according to the present invention is convenient in terms of cost and maintenance because it is convenient to carry, easy to work on site, and can use commercially available tools.

[Brief description of the drawings]

FIG. 1 is a perspective view showing the entire groove cutting device for a metal tube.

FIG. 2 is a front view of a groove cutting device for a metal tube.

FIG. 3 is a side view as viewed from a direction indicated by an arrow D in FIG. 2;

FIG. 4 is a side view as viewed from a direction indicated by an arrow E in FIG. 2;

[Explanation of symbols]

 1, 2 Frame 3 Handle 6 Screw Shaft (Spacing Adjusting Means) 7 Gas Steel Pipe (Metal Pipe) 8 Rotary Roller 9 Rotary Motor 11 Rotary Blade 13 Center Blade 14 Side Blade A Rotating direction of rotating roller B Rotating direction of rotating blade C Cutting direction

Claims (3)

[Claims] 1. A pair of frames sandwiching a side surface of a metal tube are connected by an interval adjusting means, and the inner surface of the frame is brought into contact with the inner surface of the metal tube to rotate in one or both directions in the circumferential direction of the metal tube. A groove cutting device for a metal pipe, comprising: a rotary roller; a rotary motor mounted on one of the frames; and a rotary blade capable of forming a groove that rotates along a cross-sectional direction of the metal pipe. . 2. The groove cutting device for a metal pipe according to claim 1, wherein a handle is provided at one end of the frame. 3. The bevel cutting device for a metal tube according to claim 1, wherein the rotating roller is rotatable in only one direction in a circumferential direction of the metal tube and is not rotatable in the other direction. A bevel cutting device for a metal pipe, wherein the direction in which rotation is impossible is a reversal direction with respect to the rotation direction of the rotary blade.