JPS5921686B2 - Insulation device for reducing disc cards of hot extruded materials - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heat insulating device used to reduce the amount of Tiskirt generated when forming a metal material using a hot extrusion press.

In a hot extrusion press, the rear end of the billet comes into contact with the extrusion tool, causing a temperature drop and increasing deformation resistance, so that a portion of the billet remains in the container.

This remaining billet is called a tiscart and is cut and removed after extrusion is completed.

This discard accounts for 4-5% of the billet weight,
This was the main cause of decreased product yield.

In order to remove the discards, as shown in FIG. Cut by the blade 12.

After completion of extrusion, the rear end of the billet has an appropriate number of bite holes 13 and a container 7 provided on the outer periphery of the front surface of the dummy block 2.
By retracting the container 7, the discard 10 and the extruded product can be retracted.

After cutting and separating the discard 10 and the extruded product, the stem 5 is advanced to remove the dummy block 2 with the discard 10 from the container 7.

In order to reduce the discard 10, it is necessary to prevent a drop in temperature at the rear end of the billet.

Therefore, it may be possible to insert a heat insulator between the billet and the dummy block.

However, simply inserting the heat insulator does not cause the above-mentioned biting, so the discard and extruded product cannot be retreated to the rear of the die, making it difficult to cut and separate the discard and extruded product.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an insulating device for use in reducing discards, increasing product yield, and allowing the discards to be cut and removed by conventional operations.

The present invention defines the optimal shape of a heat insulator inserted between a billet and a dummy block.

That is, the heat insulating device of the present invention is made of a suitable heat insulating material, has an outer diameter smaller than the outer diameter of the billet so that the rear end of the billet can fit between the container and the dummy block, and has legs at the bottom. It is characterized by this.

The present invention will be explained in detail below based on the drawings.

FIGS. 2 and 3 (viewed along line A-A in FIG. 2) are examples of pipe extrusion.

5 is a stem that slides back and forth, and 6 is a mandrel that passes inside the stem 5 and slides in the same way as the stem 5.

7 is a container, 9 is a lubricating glass disk inserted into the container, and 8 is a die facing the container 7.

The heated billet 1 is loaded onto a billet loader 4 together with a dummy block 2 for removing force and delivered to an extrusion line.

At this time, the heat insulator 3 of the present invention is inserted between the rear end surface of the billet 1 and the front end surface of the dummy block 2.

The outer diameter of the heat insulator 3 is 30 to 60 mm smaller than the outer diameter of the billet 1, and the inner diameter is 10 to 151 mm smaller than the outer diameter of the mandrel.
It is a large glass disk with a thickness of about 10 mm, and as shown in the figure, it is provided with legs for being supported by a billet loader 4.

Then, the stem 5 and the mandrel 6 move forward and the billet 1 enters the container 7.

The mandrel 6 passes through the inside of the billet 1 and enters the hole of the die 8, and by applying pressure to the stem 5, the billet 1 is extruded between the mandrel 6 and the die 80 to become a pipe 11.

At this time, the glass disk 9 for lubrication is billet 1 and die 8.
Represents the lubricating effect between

Also, lubrication between billet 1 and mandrel 6 is provided by billet 6.
This is done using glass powder attached to the surface.

When extrusion molding is completed, as shown in FIG. 4, the periphery of the discard 10 is wedged between the dummy block 2 and the container 7, and the heat insulator 3 is placed inside.

Therefore, by retracting the container 7, the dummy block 10 can be retracted from the die 8 and cut by the rotary saw blade 12.

If the difference between the outer diameter of the heat insulator 3 and the outer diameter of the billet is less than 30 mm, the amount of biting between the dummy block 2 and the container 7 from around the discard 10 will be insufficient when extrusion is completed. When the block 7 is moved backward, the dummy block 2 and the discard 10 become separated, making it difficult to cut and remove the discard 10.

Moreover, if the length exceeds 60 m and 7 ft, there is no such problem, but the amount of discard increases, making it impossible to achieve the intended purpose.

If the difference between the inner diameter of the heat insulator 3 and the outer diameter of the mandrel is less than 10 mm, the mandrel 6 may collide with the outer diameter of the mandrel and be damaged. It cannot be achieved.

In this example, only the extrusion of a pipe has been described, but when a solid material such as a shape material is extruded, a mandrel is not used, so the holes in the heat insulator 3 are not necessary.

The heat insulator 3 may be a glass disk formed by hardening glass powder with water glass, or may be formed by molding a suitable heat insulating material.

The thickness of the heat insulator 3 is 5 to 20 mm in consideration of strength and cost.
nrft is suitable.

In addition, the shape of the legs is straight as shown in Figure 3, stepped as shown in Figure 5, two legs as shown in Figure 6, and combinations of these, such as the above-mentioned bite from the periphery of the discard. Any shape that does not prevent this is fine.

Examples of the present invention are shown below.

Example 1 A straight type heat insulator made by solidifying lubricating glass with water glass was used.

Example 2 Steel type Ordinary steel STKM 17A Billet dimensions 254φ×74φX670 (2441
c9) Product dimensions 110φX21.5t (mandrel diameter 68mm) (Note) The heat insulator was formed by solidifying lubricating glass with water glass.

The shape was D with straight legs (see the figure below).

*1 Discard dislocation When the container and stem are moved back, the discard and dummy block become separated, making it extremely difficult to separate them from the product.

In Example 2, the relationship between the heat insulator dimensions and the discard weight/billet weight is shown in FIG. 7.

As shown in Tables 1 and 2, the ratio of discard weight to billet weight was 4 to 5 in the conventional method, but 1 in the method of the present invention.
．． His score improved dramatically to 2-2.

By inserting the heat insulating device of the present invention between the billet and the dummy block in this way, it is possible to prevent a drop in temperature at the rear end of the billet, and to reduce the weight of the Tiskirt by half, allowing hot extrusion of metal materials. Contributes to improved yield.

[Brief explanation of the drawing]

Fig. 1 is a side cross-sectional view of the main part of a hot extrusion molding device, Fig. 2 is a side view of the main part of the equipment showing how the heat insulating device of the present invention is used, and Fig. 3 is a cross-sectional view of the main part of the hot extrusion molding device. Arrow view, Figure 4 is B- in Figure 3
A view taken along the line B, FIGS. 5 and 6 are front views of an embodiment of the heat insulating device of the present invention, and FIG. 7 shows the dimensions and weight of the heat insulating device.
It is a figure showing the relationship with billet weight. 1... Billet, 2... Dummy block, 3... Insulator, 4... Billet loader-15... Stem, 6... ...Mandrel, 7..."°°Container, 8°°. ...Dice, 9...Glass disk for lubrication,
10... Discard, 11... Pipe, 12... Rotating saw blade, 13... Biting 1,000-

Claims (1)

[Claims] 1. A hot extrusion device made of a heat insulating material, having an outer diameter smaller than the billet outer diameter so that the rear end of the discard can fit between the container and the dummy block, and having legs at the bottom. Insulation equipment for reducing material discard.