JPH05245532A - Rotary wheel type extruding device for multi-hole tube - Google Patents

Abstract

PURPOSE:To prevent seam like defect and break of comb teeth from occurring by forming the shape of a mandrel so as to extrude stocks to be extruded by preliminarily once kneading plural stocks to be extruded. CONSTITUTION:Stocks 10 to be extruded inside two outer circumferential grooves 2 provided on the peripheral edge of a wheel 1 are forcibly pressed with the frictional force of the wheel, abutted on an abutment 11, and allowed to flow into an accumulating room 4. Inside the room 4, the stocks 10 are divided into two with a mandrel 7 near a die 5, but two stocks 10 are allowed to flow in the opening part 9 of the mandrel 7 near the wheel 1 while being kneaded to be homogenized. In such a way, since the temperature and the pressure of metals of both sides holding the mandrel 7 between are homogenized, the seam like defect is eliminated, the force exerted on the comb teeth is balanced between both sides of the mandrel and the break of the comb teeth is prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary wheel type extruder capable of efficiently producing a high quality multi-hole tube.

[0002]

2. Description of the Related Art Since a multi-hole tube such as a condenser tube of a car air conditioner has a small cross section, it can be efficiently manufactured by a rotary wheel type extrusion device suitable for extruding a small cross section material. This rotary wheel type extrusion apparatus has a wheel 1 which has an outer peripheral groove 2 and is rotatably supported as shown in FIG.
And a shoe 12 that has a projection that engages with the wheel 1 and that fits and slides in the outer peripheral groove 2, and that covers a part of the outer peripheral groove 2 in the longitudinal direction to form a passage. Is provided with a collecting chamber 4 which communicates with the outer peripheral groove 2 through a communication port 3 and which has a die 5 at its tip and communicates with the outside.
In the center of the, a mandrel (not shown) whose tip is formed in a comb-teeth shape is arranged with the tip of the comb-teeth protruding into the hole of the die 5.

By the way, the extruded material 10 used in such a rotary wheel type extruding apparatus has conventionally used a large diameter rough drawn wire of about 15 mmφ, but it is difficult to handle because a large diameter rough drawn wire has a large rigidity. Moreover, since a relatively thin wire drawing wire of 9 to 10 mmφ is used for the wire material, it is difficult to obtain a wire drawing wire of 15 mmφ. Under such circumstances, a method has been proposed in which a plurality of thin-diameter wire drawing wires are used instead of the large-diameter wire drawing wires, which are easy to handle and easily available. 2 outer grooves on the wheel
The structure of the periphery of the gathering chamber of the rotary wheel type extruder when two main extrusions are used and the two extrusion materials are used is as shown in FIG. A collection chamber 4 is provided which communicates with the outer peripheral groove 2 through the communication port 3 and has a die 5 at the tip thereof and communicates with the outside, and at the center of the collection chamber 4, a mandrel 7 having the tip shaped like a comb tooth, The comb tooth-shaped tip portion 8 is arranged so as to project into the hole of the die 5, and the collecting chamber 4 is completely divided into two by the mandrel 7. In such a rotary wheel type extruder, the two extrusion materials supplied from the wheel are separately press-fitted into the two collecting chambers partitioned by the mandrel 7 as the wheel 1 rotates, and both of them are mandrel 7.
For the first time, they meet at the comb-teeth-shaped tip 8 and are extruded as a multi-hole tube.

[0004]

However, in the conventional multi-hole pipe manufactured by such a rotary wheel type extrusion method, as shown in FIG. 5, a seam-like defect is formed in the central portion of the cross-section of the multi-hole pipe 13. Therefore, there were problems that the multi-hole tube obtained was inferior in mechanical strength and corrosion resistance, and the comb teeth at the tip of the mandrel were easily damaged.

[0005]

The present invention has been eagerly studied in view of the above situation, and a seam-like defect occurs in the central portion of the cross section of an extruded multi-hole tube, and the comb teeth of a mandrel are damaged. Is that the temperature and the extrusion pressure of the extruded material extruded from both sides of the mandrel are different, and further research has been conducted to complete the present invention. That is, the present invention has a wheel that has a plurality of outer peripheral grooves and is rotatably supported, and a projection that engages with this wheel and that fits into and slides in each outer peripheral groove. A shoe that covers a part of the direction to form a passage, the shoe is provided with a collecting chamber that communicates with each outer peripheral groove through a communication port, and has a die at the tip to communicate with the outside. In the center of the chamber, a mandrel whose tip is formed into a comb tooth shape, in the rotary wheel type extrusion device for a multi-hole tube in which the comb tooth-like tip is arranged so as to project into the die hole, the mandrel near the wheel. A rotary wheel type extrusion device for a multi-hole tube, characterized in that an opening is provided at a predetermined portion so that extrusion materials supplied from a plurality of outer peripheral grooves of the wheel can flow through each other.

In the extrusion apparatus of the present invention, a plurality of extruded materials supplied from the wheel are temporarily kneaded in the vicinity of the inlet of the collecting chamber by providing an opening on the inlet side of the collecting chamber of the mandrel which divides the inside of the collecting chamber, that is, the wheel side. By equalizing the temperature and pressure of the metal flow extruded from both sides of the mandrel at the tip of the mandrel, the seam-like defect at the center of the cross section of the multi-hole tube is eliminated and the comb teeth are prevented from being damaged. It is a thing.

The present invention will be specifically described below with reference to the drawings. 1A, 1B, 1C and 1C are a lateral sectional view and a longitudinal sectional view, respectively, showing an example of the peripheral structure of the collecting chamber of the device of the present invention and a sectional view taken along the line AA of FIG. The two outer peripheral grooves 2 of the wheel 1 are the communication ports 3
It is connected to the meeting room 4 via. A die 5 is installed at the tip of the gathering chamber 4, and the wheel 1 of the gathering chamber 4 is
An annular tool 6 is fitted on the inner wall of the side wall, and a mandrel 7 having a comb-shaped tip is formed at the center of the annular tool 6.
However, the comb tooth-shaped tip portion 8 is arranged so as to project into the hole of the die 5, and an opening 9 is formed near the wheel 1 of the mandrel 7.
Is provided.

Next, the process of continuously extruding a multi-hole tube using this extrusion device will be described with reference to FIG. Extruded material 10 in two outer peripheral grooves 2 provided on the periphery of the wheel 1
Is pressed by the frictional force when the wheel rotates, and hits the abutment 11 installed in front of the outer peripheral groove 2,
It turns 90 degrees in the direction of travel and flows into the collecting chamber 4 through the communication port 3. Inside the gathering room 4, the die 5 is closer to the mandrel 7
Although separated, the two extruded materials 10 flow through each other through the opening 9 provided in the portion of the mandrel 7 near the wheel 1. The flow of metal in the opening 9 is directed in a direction in which the pressure difference between the two extrusion materials 10 press-fitted from the communication port 3 and the pressure difference between both sides of the mandrel 7 at the tip of the collecting chamber 4 are reduced. In this way, the temperature and pressure of the metal on both sides sandwiching the mandrel 7 at the tip of the mandrel 7 are equalized, and the two extruded materials 10 are well kneaded and homogenized in the opening 9.
In the present invention, the opening provided in the mandrel is provided with the end portion of the mandrel near the wheel as shown in FIG.
Therefore, it is preferable that the metal is sufficiently homogenized. The shape of the mandrel is such that the end portion 15 near the wheel is formed into a mountain shape, as shown in FIGS. 2A and 2B, its side and cross-sectional views, or in FIG. 2C, the cross-sectional view of other mandrels. It is preferable to reduce the pressure of the extruded material that is press-fitted into the mandrel and improve the metal surroundings.

[0009]

In the apparatus of the present invention, each outer peripheral groove has a plurality of outer peripheral grooves, a wheel rotatably supported, and a projection that engages with the wheel and fits into and slides in each outer peripheral groove. And a shoe that covers a part of the longitudinal direction of the shoe to form a passage, and the shoe is provided with a collecting chamber that communicates with each outer peripheral groove through a communication port and has a die at the tip to communicate with the outside.
In the center of this collecting chamber, a mandrel whose tip is formed in a comb tooth shape, in a rotary wheel type extrusion device of a multi-hole tube in which the comb tooth-shaped tip is arranged so as to project into the die hole,
Since the opening portion is provided at a predetermined portion of the mandrel near the wheel, the plurality of extruded materials supplied separately from the plurality of grooves of the wheel flow through each other through the opening portion of the mandrel and are homogenized to make the mandrel. The metal supplied from both sides satisfactorily coalesces at the tip of the mandrel, eliminating seam-like defects. Further, the temperature and pressure of the metal on both sides of the mandrel are equalized and the force applied to the comb teeth is balanced on both sides of the mandrel, so that the comb teeth are not damaged.

[0010]

EXAMPLES The present invention will be described in detail below with reference to examples. Manufactured by belt wheel type continuous casting and rolling method
After drawing and stripping 19.8 series Al wire drawing wire of 9.8 mmφ,
It was degreased to form a 9.3 mmφ extruded material, and this extruded material was continuously extruded into a multi-hole tube at a speed of 90 m / min. As the wheel, a wheel having two outer peripheral grooves was used. As the collecting chamber, there were used one having the structure of the present invention in which an opening is provided in the mandrel near the wheel, and one having a conventional structure in which the mandrel is not provided with an opening and the collecting chamber is completely divided into two. The height of the opening of the mandrel (h in FIG. 1A) was changed in three ways. The multi-hole pipe has the same shape as that shown in Fig. 5 and has a cross-sectional dimension of 20 mm x 2 mm in outer diameter and 0.5 mm in wall thickness.
A multi-well tube was extruded. The resulting multi-hole pipe was subjected to seam-like defect occurrence and corrosion resistance test. Also, the damage condition of the comb teeth at the tip of the mandrel was recorded. The results are shown in Table 1. The corrosion resistance test was performed by a salt spray test.

[0011]

[Table 1] Figure 1 Dimensions of the mandrel opening end shown in a and b, in mm. Percentage weight loss after washing with water by spraying a 10% NaCl aqueous solution at a temperature of 30 ° C for 100 hours.

As is clear from Table 1, the products of the present invention (No.
1-3 were of high quality with no seam-like defects. Moreover, the comb teeth were not damaged. The higher the height of the opening of the mandrel, that is, the wider the opening, the less the seam-like defects and the better the corrosion resistance. On the other hand, in the comparative example No. 4, the comb teeth were damaged during the preheating step using the short material before the start of extrusion. Further, the obtained multi-hole tube was found to have a seam-like defect as shown in FIG. This multi-hole pipe had an extremely large corrosion weight loss in a salt spray test and was inferior in corrosion resistance. Although the rotary wheel type extrusion apparatus having two wheels has been described above, the same effect can be obtained by an apparatus using a wheel having three or more grooves.

[0013]

As described above, according to the extrusion apparatus of the present invention, since a plurality of extrusion materials are well kneaded with each other through the opening of the mandrel, the seam-like defect which occurs in the longitudinal direction of the multi-hole pipe is eliminated. In addition, the temperature and pressure of the metal on both sides of the mandrel are made uniform, and the comb teeth at the tip of the mandrel are prevented from being damaged, resulting in a remarkable industrial effect.

[Brief description of drawings]

FIG. 1 is a lateral and vertical cross-sectional view and a cross-sectional view taken along the line AA in FIG. 1A, showing an example of a peripheral structure of a gathering chamber of an extrusion apparatus of the present invention.

FIG. 2 is a cross-sectional view showing an example of a mandrel used in the extrusion apparatus of the present invention.

FIG. 3 is an explanatory view of a main part of a rotary wheel type extrusion device.

FIG. 4 is a transverse cross-sectional view of a peripheral portion of a collecting chamber of a conventional rotary wheel type extruder.

FIG. 5 is a cross-sectional explanatory view of a multi-hole tube.

[Explanation of symbols]

 1 Wheel 2 Outer Groove 3 Communication Port 4 Collecting Room 5 Die 6 Annular Tool 7 Mandrel 8 Comb Toothed Tip 9 Opening 10 Extrusion Material 11 Abutment 12 Shoe 13 Multi-hole Pipe 14 Seam Defect 15 End of Mandrel toward Wheel Department

Claims (1)

[Claims] 1. A wheel having a plurality of outer peripheral grooves, which is rotatably supported, and a projection which engages with the wheel and fits into and slides in the respective outer peripheral grooves. And a shoe that covers a part of the passage to form a passage. The shoe is provided with a collecting chamber that communicates with each outer peripheral groove through a communication port, and has a die at the tip to communicate with the outside. A mandrel having a comb-shaped tip formed at the center of the mandrel, in a rotary wheel type extrusion device for a multi-hole tube in which the comb-shaped tip is arranged so as to project into the die hole. A rotary wheel type extrusion device for a multi-hole tube, characterized in that an opening portion is provided at a portion so that extrusion materials supplied from a plurality of outer peripheral grooves of the wheel can flow through each other.