JPH04106134U - pipe clamping device - Google Patents

Abstract

(57) [Summary] [Purpose] To prevent pipe deformation during clamping. [Structure] Arc surfaces 2a, 2b of clamp members 1a, 1b
Grooves 3a and 3b are provided in the center of the pipe 10, respectively, and when clamping, the edges a ₁ , a ₂ , b ₁ , b ₂ on both sides of the groove are used to secure the pipe 10.
I support 4 points.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

The present invention relates to a clamping device for a pipe beveling machine.

0002

[Conventional technology]

Conventionally, a clamping device like the one shown in Figure 3 has been used for chamfering of electric resistance welded pipes, etc. It is. That is, the inner part of the pair of clamp members 1a and 1b arranged vertically opposite to each other. Arc surfaces 2a and 2b for sandwiching the pipe 10 are provided on the surfaces. And chamfering In this case, the pair of clamp members 1a and 1b are connected to a hydraulic system (not shown) as shown in FIG. After pressing and fixing the pipe 10 with the circular arc surfaces 2a and 2b, While rotating the head 21 of the chamfering machine on the pipe end side, feed is given to the head 21, and the head The pipe end is cut and chamfered with a cutting tool 22 fixed to the pipe 21. In addition, it is possible to clamp several sizes of pipes with one clamping device. For example, there is Utility Model Publication No. 62-8982. This requires the arc surface above. It is formed of continuous arc parts with different radii of curvature to fit the pipe diameter of the size. It is something.

0003

[Problem that the idea aims to solve]

In the above-mentioned clamping device, generally the diameter of the clamp (the arcuate surface 2a , 2b diameter) is approximately 1% larger than the pipe diameter to prevent damage to the pipe. It has been made. Therefore, when the pipe is clamped, the pipe As a result of supporting the pipe 10 almost at two points a and b, the pipe 10 is deformed into an oval shape. Mau. When such a deformation of the pipe occurs, the orbit of the cutting tool 22 rotating in a perfect circle The marks do not match the part of the pipe that should be cut, resulting in chamfering defects.

0004 In addition, since the degree of pipe deformation differs depending on the pipe thickness and pipe strength, It will take time to adjust the chamfer.

[0005] This invention was made to solve the above problems, and when clamping The purpose of the present invention is to provide a clamping device that prevents deformation of pipes in do.

[0006]

[Means to solve the problem]

In order to achieve the above object, the pipe clamping device according to the present invention has a pair of A pipe clamping device having a clamping member whose facing inner surface is formed into an arcuate surface. A groove is provided in the center of each arcuate surface, and the edge of this groove allows the pipe to be It was designed to be supported by points.

[0007]

[Effect]

In the clamp device of the present invention, when a pipe is clamped, a pair of clamp members The pipe is supported at four points by the edge of the groove provided in the center of the arcuate surface of the inner surface of the pipe. In addition, since the pipe is pressed evenly at these four points, the amount of deformation of the pipe is reduced.

[0008]

【Example】

FIG. 1 is a front view showing an embodiment of the present invention. In the figure, 3a and 3b are grooves provided in the center of the arcuate surfaces 2a and 2b of the clamp members 1a and 1b, respectively, and a total of four edge portions formed by the arcuate surfaces 2a and 2b and the grooves 3a and 3b. a ₁ , a ₂ , b ₁ , and b ₂ serve as support points for the pipe 10. The outer diameters of the arcuate surfaces 2a and 2b are made slightly larger than the pipe diameter, as in the past. The groove width is determined by the angle θ from the clamp center O (total width 2θ), and depending on the pipe size, θ=20°. The depth of the groove is set to such an extent that the pipe does not touch the bottom of the groove when clamped.

When the pipe 10 is clamped using the clamp members 1a and 1b configured in this way, the pipe 10 is clamped at four points by the edge portions a ₁ , a ₂ , b ₁ , and b ₂ as shown in FIG. Supported and evenly pressed. Therefore, the pipe 10 can be clamped in a perfect circle without being deformed into an oval shape as in the conventional case.

0010 A specific usage example is as follows. A pipe with an outer diameter of 165.2 mm and a thickness of 5.0 mm was manufactured under the conditions shown in Table 1. Using a lamp device, the outer diameter was measured before and during clamping. Display the results Shown in 2.

[0011]

[Table 1]

0012

[Table 2]

However, in Table 2, d ₁ is the outer diameter of the pipe in the vertical direction (y-axis direction), d ₂ is the outer diameter of the pipe in the 45° direction, and d ₃ is the outer diameter of the pipe in the lateral direction (x-axis direction), as shown in FIG. _d4 indicates the pipe outer diameter in the direction orthogonal to 45°.

As is clear from this result, in the conventional example, the pipe outer diameter dimension d ₁ in the y-axis direction, where the clamping force directly acts, is greatly reduced, and the pipe outer diameter dimension d 1 in the x-axis direction, which is not subjected to any external force, is significantly reduced. ₄ is greatly elongated, and the pipe is deformed into an oval shape. On the other hand, in this embodiment, since the clamping force is distributed at four locations, the pipe outer diameter dimension hardly changes in all four directions, and is the same in all four directions. As a result, the pipe maintains its perfect circle.

[0015]

[Effect of the idea]

As described above, according to the present invention, the pipe is supported at four points during clamping. This has the effect of preventing pipe deformation and greatly reducing chamfer defects. You can get results. Therefore, the adjustment time for chamfering due to differences in pipe thickness and pipe strength is significantly reduced. It can be shortened.

[Brief explanation of drawings]

FIG. 1 is a front view showing an embodiment of the present invention.

FIG. 2 is an explanatory diagram of the above embodiment before and during clamping.

FIG. 3 is a front view of a conventional clamp device.

FIG. 4 is an explanatory diagram during conventional chamfering processing.

FIG. 5 is an explanatory diagram of a conventional clamping device during clamping.

FIG. 6 is an explanatory diagram showing the measurement position of the pipe outer diameter for evaluating the deformation of the pipe.

[Explanation of symbols]

1a, 1b Clamp members 2a, 2b Arc surfaces 3a, 3b Grooves a ₁ , a ₂ , b ₁ , b ₂ Edge portion 10 Pipe

Continuation of front page (72) Creator Yuji Sato 1-1-2 Marunouchi, Chiyoda-ku, Tokyo Within Honkoukan Co., Ltd.

Claims (1)

[Scope of utility model registration request] 1. A pipe clamping device having a clamping member having a pair of opposing inner surfaces formed as arcuate surfaces, wherein an edge portion is formed in the center of each of the arcuate surfaces so as to support the pipe at four points. A pipe clamping device characterized by having a groove.