JPH0744321Y2 - Floating plug for pipe withdrawal - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention puts the lubricating oil inside the pipe and withdraws the pipe in cooperation with a die installed outside the pipe to reduce the size to a predetermined size. The present invention relates to a floating plug for pipe withdrawal (outer diameter, wall thickness).

[Conventional technology]

Conventionally, when a pipe is drawn and the size is reduced to a predetermined dimension (outer diameter, wall thickness), as shown in FIG. 2, the inner surface lubricating oil 2 is placed inside the pipe 1 to be drawn. Then, the tube 1 having a predetermined size is obtained by inserting the tube 1 into the gap between the die 4 and the floating plug 3 with the solid floating plug 3 inserted. Then, when the drawing process is completed, the inner surface lubricating oil 2 in the pipe 1 is discharged to the outside of the pipe 1 together with the floating plug 3. Therefore, it is necessary to fill the inside surface of the pipe 1 with the lubricating oil 2 every time the pipe 1 is drawn.

[Problems to be solved by the device]

The problem to be solved by the present invention is that, in the conventional drawing process of a pipe, it is necessary to add an inner surface lubricating oil to each drawing pass, and an extra lubricating oil is consumed.

The present invention has been made in view of the above circumstances, and an object of the present invention is to reduce the amount of the inner surface lubricating oil used for drawing and to fill the tube with the inner surface lubricating oil for each drawing pass. Another object of the present invention is to provide a floating plug for pulling out a pipe which can smoothly and surely pull out a pipe having a predetermined size.

[Means for Solving the Problems]

In order to achieve the above object, the present invention forms a through hole along a central axis in a central portion of a plug body having a spherical base end portion and a tapered distal end portion, and the through hole of the through hole is formed. In each of the base end opening and the tip end opening, a curved chamfered portion that is smoothly connected to each peripheral edge is formed.

[Action]

In the floating plug for pipe withdrawal of the present invention, a through hole is formed along the central axis in the center of the plug body.
By forming a curved chamfer in each of the base end opening and the tip end opening of the through hole so as to be smoothly connected to each peripheral portion, the inner surface lubricating oil filled in the pipe is completely drawn out. It is guided to the inside of the product without any resistance and promptly, and is reused as the lubricating oil for the next drawing.

〔Example〕

 An embodiment of the present invention will be described below with reference to FIG.

In FIG. 1, reference numeral 10 is a hollow plug body, and this plug body 10 has a spherical portion 10a formed at the base end, a large diameter portion 10b connected to the spherical portion 10a, and a large diameter portion 10b. A taper portion 10c that is continuous with the hole portion 10b and has a diameter that decreases toward the tip, a small diameter portion 10d that is continuous with the tapered portion 10c, and a tip portion 10e that is continuous with the small diameter portion 10d and is tapered, A through hole 10f is provided inside along the central axis. Curved chamfers (rounded portions) 10g and 10h are formed at the base end opening and the tip end opening of the through hole 10f so as to smoothly connect to the respective peripheral edges.

When the pipe 1 is drawn using the pipe drawing floating plug configured as described above, as in the conventional case, after the inner surface lubricating oil 2 is filled in the pipe 1 to be drawn, FIG. Insert the floating plug as shown in. In this state, the tube 1 having a predetermined size can be obtained by pulling out the tube 1 through the gap formed by the die hole of the die 4 and the outer peripheral portion of the plug body 10 of the floating plug. In this case, as the pipe 1 is pulled out, the inner surface lubricating oil 2 inside the pipe 1 is guided from the outside of the base end portion 10a into the through hole 10f promptly without resistance and quickly inside the through hole 10f. After flowing, it is continuously supplied to the front side of the pipe 1 and evenly distributed on the inner surface of the pipe 1 after withdrawal. Therefore, once the inner surface lubricating oil 2 is filled in the pipe 1, the next withdrawal process is performed. It is not necessary to fill the inner surface lubricating oil 2, and the drawing process can be performed as it is.

To demonstrate the above effect, the diameter of the small diameter portion 10d × the large diameter portion 1
The diameter of 0b is φ31.5mm × φ36.3mm and φ25.3mm × φ29.5
2 kinds of floating plugs of 2 mm each were made, and for each of 12 coils (440 kg, length 446 m),
φ31.5mm × φ36.3mm floating plug is used for drawing process to make φ35mm pipe 1, then this pipe 1 is drawn with φ25.3mm × φ29.5mm floating plug for φ28mm pipe. 1 was formed, it was possible to carry out the drawing process only with the inner surface lubricating oil 2 that was initially filled and without supplementing the lubricating oil later.

Here, the diameter of the through hole 10f of each of the floating plugs was initially set to 5 mmφ, but this was not sufficient, and at the time of the second drawing, the pipe 1 broke due to oil shortage. Therefore, when the diameter of the through hole 10f was set to 8 mmφ and the rounded portion 10g was formed, the inner surface lubricating oil 2 was smoothly sucked into the through hole 10f, and the pipe 1 could be extracted without breaking. The drawing speed was 600 m / min.

[Effect of device]

As described above, according to the present invention, a through hole is formed along a central axis in a central portion of a plug body having a spherical base end portion and a tapered front end portion, and the base end of the through hole is formed. A curved chamfer is formed at each of the opening and the tip opening so that it smoothly connects to the peripheral edge of the opening and the inner surface of the tube. This internal lubrication oil can be reused as the lubricating oil for the next drawing, the amount of internal lubrication oil used for drawing can be suppressed, and the internal lubrication oil can be used for each drawing pass. It is not necessary to replenish
It is possible to smoothly and surely pull out a pipe having a predetermined size.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention, and FIG. 2 is a sectional view explaining a conventional pipe drawing process. 1 …… Pipe, 2 …… Inner lubricating oil, 10 …… Plug body, 10f
…… Through hole.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Yuma Fukushima, Creator, Fukushima, 1975, Shimoishi Togami, Kitamoto, Saitama Prefecture, 1975 2 Mitsubishi Kinzoku Co., Ltd., Kitamoto Works (72) Hiroshi Yamaguchi, 1975, Shimoishi, Kitamoto, Saitama Prefecture, 1975 2 Mitsubishi In the Kitamoto Works of Kin Metals Co., Ltd. (72) Tsujio Takahashi, 1975-2 Shimoishi Togami, Kitamoto City, Saitama Prefecture Mitsubishi Metals Co., Ltd. in the Kitamoto Works of Kitamoto Co., Ltd. (72) Shingo Fujino, 1975-2 Shimoishitogami, Kitamoto, Saitama Prefecture Inside the Kitamoto Works, Kinzoku Co., Ltd. (72) Yukio Kuramochi, 1975, Shimoishi Togami, Kitamoto City, Saitama 2 Inside the Kitamoto Works, Mitsubishi Kinzoku Co., Ltd. (56) Reference JP-A-52-7854 (JP, A) Sho 53-30395 (JP, B2) JP 59-33451 (JP, B2)

Claims (1)

[Scope of utility model registration request] 1. A floating plug for pipe withdrawing, which is carried out by putting lubricating oil into the inside of a pipe and pulling out the pipe, at the center of a plug body having a spherical base end and a tapered tip, A through hole is formed along the axis, and each of the base end opening and the tip end opening of the through hole is formed with a curved chamfer that is smoothly connected to its peripheral edge. Floating plug for pipe withdrawal.