JP3028919B2 - Extrusion molding method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for extruding an aluminum alloy or the like by means of an extrusion press, in which the billet rear end is cooled with spray water before the billet is loaded into the extrusion container, and is passed through a die from inside the container. Before the billet is extruded, the air between the container and the billet is degassed out of the container, and without containing air in the billet,
The present invention relates to an improved extrusion method for effective and efficient extrusion.

[0002]

2. Description of the Related Art When hot extrusion is continuously carried out, the temperature of the extrusion working surface side of the fixed dam block increases when the extrusion is carried out in contact with the billet due to the heat of the heated billet.

In order to lower the temperature of these fixed dam blocks, the billet temperature is lowered by so-called indirect cooling, in which the inside of the fixed dam blocks and the extrusion working surface side are cooled indirectly to cool the rear end of the billet. That was being done.

On the other hand, after a billet having a diameter slightly smaller than the inner diameter of the container is placed in the container, the billet is pressed against the die with the stem at the rear in the container, that is, when the billet is upset, the billet is crushed and the air between the container and the billet is crushed. Is compressed. In order to discharge the compressed air, the stem and the container are slightly retracted, the compressed air is extracted from the gap between the die and the container, and the container and the stem are advanced again to start extrusion. The degassing step of removing the compressed air in this way is called a burp cycle, but the presence of this step causes wasted time in the extrusion cycle.

[0005]

However, when the temperature of the extrusion working surface side of the fixed damey block at the time of extruding the billet rises due to the heat received from the aluminum alloy billet temperature, impurities and residual air contained in the billet skin portion are increased. Since the air flows into the extruded material due to the backward winding by the metal flow, there is a problem that the product yield of the extruded material is reduced due to the inclusion of blisters and impurities during the extrusion molding. Particularly in the case of extrusion molding of an aluminum alloy, experience has shown that the temperature of the extrusion working surface of the fixed dam block can be raised from 450 ° C. to 200 to 300 ° C. within an idle time of about 20 seconds by conventional indirect cooling.
There was a problem that it was difficult to descend to a great extent.

In the latter method, when the container is pressed against a die by degassing in a burp cycle, air remains at atmospheric pressure between the inner surface of the container and the outer surface of the billet in a thin state of about one skin. Has not been sufficiently degassed. Further, aluminum chips often adhere to the end faces of the container liner and the die. If it adheres in a uniform film form, there should be no invasion of air when sealing, but in general, it adheres non-uniformly, although it is scum. For this reason, even if the interior of the container is degassed, even if air enters again and the burp cycle is performed by the time the billet upset is completed, it is not complete, and blisters have been generated.

The present invention has been made in view of the above-mentioned conventional problems, and has as its object to suppress the metal flow at the rear end of the billet and to evacuate the air in the container before extrusion. By degassing,
This is to prevent the quality or yield of the extruded material from deteriorating due to mixing of residual air and impurities contained in the outer skin of the billet.

[0008]

SUMMARY OF THE INVENTION The present invention has been made to achieve the above object. In the present invention, after receiving a billet sent from a billet carrier by a billet loader, a billet loading port of an extrusion container is provided. An intermediate stop standby position of the billet loader is provided in the middle of the transfer to the billet loader. After cooling to a temperature range of about 200 to 300 ° C. while spraying a cooling medium onto the rear end of the billet during extrusion of the front billet, the extrusion is performed. A billet is loaded into the extrusion container suspended by the suspension mechanism before the container is brought into contact with the die, and a sealing block is closed at the extrusion stem side end face of the extrusion container with respect to the extrusion stem during which the billet is being pushed. In this state, the air accumulated on the extrusion stem side of the container is pressed against the die side before starting the billet extrusion. And so as to degas both the stem side.

[0009]

According to the above construction, the billet is cooled by spraying a cooling medium directly on the rear end of the billet placed on the billet loader. That is, the intermediate stop standby position of the front billet loader is provided, and after the temperature of the rear end of the billet is detected by the temperature detector during the extrusion of the front billet, the cooling medium is sprayed on the rear end of the billet to quickly extrude the billet. It can be reduced efficiently.

The billet having its billet rear end cooled to a desired temperature must be pushed in by an extrusion stem, and suction must be degassed from both the die side of the container and the stem side of the container before starting extrusion.

When the air is sucked from the die side of the container, firstly, the air is sucked from the die end side of the container and sealed with a seal block which can be opened and closed in the axial direction of the container, and then attached to the tip of the container. In a state where the seal ring that is engaged with the outer ring and is movable in the axial direction and seals the end surface of the die ring on the container side, air is sucked through the minute gap between the die and the container, Air between billets can be completely degassed,
An extruded material without blisters is obtained.

[0012]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is an explanatory view showing one embodiment of a degassing system for an extrusion container according to the present invention, and FIG.
A is a front view as viewed from A, and FIG. 3 is an explanatory view in which the tip of a billet is pressed against a die and then vacuum suction is performed from both containers.
Is an explanatory view of vacuum suction from both sides of the container immediately before pressing the billet tip against the die, FIG. 5 is a front view as viewed from BB of FIG. 1, and FIG. 6 sucks air through a minute gap between the die and the container. FIG. 7 is an enlarged cross-sectional view of a main part of the suction unit, FIG. 7 is a schematic diagram of a temperature adjusting device at the rear end of the billet according to the present invention, FIG. 8 is a cross-sectional view of the main part of the temperature adjusting device shown in FIG. 10 is a front view of a billet loader, FIG. 11 is a block diagram of a billet loader, and FIG. 12 is a conceptual diagram showing how a billet pressed in a container is crushed. It is. The container tire 2 and the container 1 are installed on the end platen 32 of FIG.
The main part of the C portion on the piston head side of the container cylinder 33 that slides the moving stopper block 34 and the head block 35 also serving as a stopper, and the piston 37 moves at the maximum distance within the range in which the moving stopper block 34 moves.
Indicates that the end face of the container 1 on the die 3 side is 3
The structure has a temporary stop mechanism 30 that can perform a temporary temporary stop with a gap (gap) 6 of about 3 mm. A hollow rod 39 in which a plurality of communication holes for oil passage are arranged in a staggered manner in the axial direction is integrally attached to a rear shaft core portion on the head side of the piston 37 by screws or the like, and the piston 37 is retracted. Occasionally, the hollow rod 39 enters the hole at the front end of the movement stopper block 34. In FIG. 1, reference numeral 36 denotes a cylinder tube constituting a part of the cylinder main body, 35 denotes a head block at the rear of the cylinder main body, 37 denotes a piston, and 38 denotes a piston rod.

Reference numeral 3 denotes a die, and the outer periphery of the die 3 is slidably fitted and held on the inner peripheral surface of the die ring 5. Numeral 6 is a gap, and a gap 6 of, for example, 2 to 3 mm is provided between the container 1 and the die 3 or the die ring 5 by a temporary stop mechanism provided in the container cylinder 33. Reference numeral 31 denotes a gap between the inner peripheral surface of the container and the outer peripheral surface of the billet 13, which is also a degassing space.

On the other hand, the extrusion stem 1 for pushing the billet 13
4 is provided with a fixed dam block 70 that can be in close contact with the inner surface of the container 1. The fixed dam block 70 is provided with a dummy block rear member 17 fixed to the distal end of a tubular member 16 fixedly mounted on the axial center of the extrusion stem 14 by screws. An outer ring 18 that is attached and whose distal end portion can expand in the outer diameter direction and can come into close contact with the inner peripheral surface of the container 1. 14a is a stem holder, 14b
Is a crosshead.

Next, in this embodiment, the vacuum suction device 50 for the air in the container 1 on the die 3 side and the extrusion stem 14 side in the container 1 will be described.

First, as shown in FIG. 6, a vacuum suction device 50 for removing air on the side of the die 3 in the container 1 has an outer ring 10 concentric with the container 1 fixed to an end surface of the container tire 2 on the side of the die 3 by bolts. Has been established. Further, a seal ring 11 is provided on the inner peripheral surface side of the outer ring 10 so as to be able to move forward and backward and not to be disengaged in a stepwise manner. Part of the seal ring 11 has a structure having a protrusion 11a protruding in the center direction. When the container 1 is temporarily stopped with a gap of, for example, 2 to 3 mm left between the container 1 and the die 3, the die ring 5, the projection 11a of the seal ring 11 is
(In the present embodiment, eight springs 12 are mounted at equal intervals between the container tire 2 and the seal ring 11) to be pressed and abutted in the pushing direction (face seal), so that the clearance becomes zero. I have.

As shown in FIG. 6, two deaeration holes 7 are provided above the seal ring 11, and are connected to a vacuum tank 20 and a vacuum pump 21 via a pipe 8 and an electromagnetic switching valve 9, respectively. 22 is a motor, 23 is a heat-resistant sealing material for preventing air from entering between the outer ring 10 and the seal ring 11, 24 is a metal hollow ring for preventing air from entering between the outer ring 10 and the container tire 2, and 25 is a die ring. 5 is a replaceable seal plate that prevents direct wear and air intrusion of the protrusion 11a of the seal ring 11 by repeated contact with the seal ring 11.

Next, a vacuum suction device 60 for removing air on the side of the extrusion stem 14 in the container 1 is disposed on the end face of the container 1 on the side of the extrusion stem 14 as shown in FIG.
On the end face of the container 1 on the side of the extrusion stem 14, a split seal block 40 is provided so as to be openable and closable in a direction perpendicular to the axial direction of the container 1, and when the seal block 40 is closed, It can be brought into close contact with the outer peripheral surface of the extrusion stem 14 via the seal packing 41 provided.

Reference numeral 42 denotes a guide plate, and both blocks of the seal block 40 can be opened and closed by a cylinder 43, respectively. 41 and 44 are seal packings,
A degassing hole 45 is provided in a part of the seal block 40, and the degassing hole 45 is connected to the vacuum tank 20 via a pipe 8a. Reference numeral 46 denotes an electromagnetic switching valve, 47 denotes a heat insulating material, and a part of the heat of heating the container 1 is prevented from being transmitted to the vacuum suction device 60 by heat conduction. Is disposed via a cover plate 48 disposed at the same time.

Next, the temperature adjusting device 110 at the rear end of the billet will be described with reference to FIGS. The temperature adjusting device 110 at the rear end of the billet is disposed on the machine base 112 on the extrusion cylinder side adjacent to the billet loader 111.

Temperature control device 110 at the rear end of the billet
Is a cooling nozzle 115, a contact-type temperature sensor device 113,
Displacement sensor device 124, cover 116, linear guide 1
17, an air cylinder 118, a control device 119, an electromagnetic valve 120, and a movable base 121.

An air cylinder 118 is provided on a base 122.
And a linear guide 117 are provided. When air is supplied before and after the piston of the air cylinder 118, the linear guide 11 is moved with the expansion and contraction of the piston rod 118a.
A movable base 121 that moves forward and backward while suspended on the top 7 is provided.

The moving base 121 has a structure having a projecting portion 121a having an inverted L-shaped side surface. The center of the projecting portion 121a is formed, for example, with water toward the rear end 13a of the billet. A cooling nozzle 115 is provided so that a cooling medium such as the above can be sprayed.

The cooling nozzle 115 sprays water to a billet rear end 13a in a state where water is made into a fine droplet diameter by a so-called two-phase mixture spray method of a spray gas using compressed air and a liquid such as water. To cool down.

When spraying water from the cooling nozzle 115 toward the billet trailing end 13a, the billet trailing end 13 is used to prevent the sprayed water from scattering.
cover 11 having an open side a and a cut cross section having a U-shape
6 are provided on the protruding portion 121a.

At the eccentric position between the cooling nozzle 115 and the cover 116, a contact-type temperature sensor device 113 for measuring the surface temperature of the billet rear end 13a is provided.
It is arranged in the same direction as.

A displacement sensor device 124 is provided at the rear of the contact-type temperature sensor device 113 on the same axis line as the extension line. A displacement sensor 124a is provided at the tip of the displacement sensor device 124, Apparatus 1
24, it is configured to contact the rear end.

A spring 123 is mounted on a peripheral portion of the contact-type temperature sensor device 113 in the middle thereof. For this reason, the temperature sensor 113a such as a thermocouple is constantly urged to press the tip of the temperature sensor 113a. About 1 from tip of cover 116
It protrudes 0 mm.

The interior of the displacement sensor 124 is also provided with a spring (not shown) similarly to the contact-type temperature sensor 113 described above, and the displacement sensor 12
4a is configured to be capable of contraction and extension by the tension of the spring.

On the other hand, the displacement sensor device 124 is
The air cylinder 1 continues even after the temperature sensor 113a projecting about 10 mm from
Since the movable base 121 approaches the billet rear end 13a side by the extension of the piston rod 118a of 18, the temperature sensor 113a overcomes the extension tension of the spring 123 and contracts.

As the moving base 121 approaches the billet 13 side, the displacement sensor device 124 detects that the distance between the cover 116 and the billet rear end 13a is, for example, 2 to 3 mm. Degeneration amount about 7-8m
The value is inversely converted from m and stops at that position.
Therefore, the cover 116 does not come into contact with the billet rear end 13a.

Reference numeral 119 denotes a control device, 120 denotes an electromagnetic valve, and 125 denotes a shear device.

The billet loader 111 shown in FIG.
o. 1 billet loader 111a and the No. 1 billet loader. It is composed of a two-bilette loader 111b, and transfers and supplies the billet 13 as a molding material to the billet loading port 126 of the container 1. This is performed by a billet carrier 127 installed on one side of the molding machine. The sent billets 13 are grasped one by one and lifted and moved to the billet loading port 126 of the container 1. In addition, No. 1 billet loader 111a and the No. 1 billet loader. The two billet loaders 111b have the same configuration.

As shown in FIG. 11, billet carrier 1
27 causes billet 13 to move to the lower position of container 1
The billet loader 111 is configured to be gripped and transferred to the billet loading port 126 while being supplied one by one. For this reason, the billet loader 111 is disposed so as to face the billet carrier 127, and includes a swing arm 128 formed to be pivotable along a plane orthogonal to the extrusion center line of the molding machine.

That is, the swing arm 128 has one end pivotally connected to a turning center shaft 130 disposed outside the lower tie rod 129 of the molding machine, and has an enlarged V-shape so as not to interfere with the tie rod 129 during a swing operation. It is bent and extends below the container 1 from the lower portion of the tie rod 129. Then, the tip of the swing arm 128 swings and the mounting table 131 of the billet carrier 127 is moved.
And the billet loading port 126 of the container 1.

In order to perform a swing operation, a hydraulic drive cylinder device 132 is connected to the swing arm 128, and the swing arm 128 is driven by the expansion and contraction operation.

Here, a billet holding portion 133 that holds the billet 13 is attached to the tip of the swing arm 128.

The billet holding portion 133 is a pedestal 134 for supporting the lower surface of the billet 13 at the container loading position.
Are arranged in a V-shape.

Next, the extrusion molding method will be described.

First, the direct cooling of the billet 13 is performed as follows. In the present embodiment, the material of the billet 13 is an aluminum material. Although the extrusion time of the billet 13 varies depending on the diameter and length, the extrusion of one billet 13 requires about 60 to 90 seconds.

During the extrusion of the billet 13 in the previous cycle, the rear end portion 13a of the billet in the next cycle must be cooled, which is performed as follows.

That is, under the condition that about half of the billet 13 of the previous cycle is extruded from the die 3 to form an extruded material, the billet 13 of the next cycle is stopped on the billet loader 111 at the intermediate stop position, Rear end 13
It is necessary to start cooling of a.

First, the billet loader 111 is No.
Hydraulic drive cylinder device 13 of one billet loader 111a
The swing arm 128 is moved downward by extending and retracting the billet 2, and the billet holding portion 133 at the tip is opposed to the mounting table 131 of the billet carrier 127 as shown by a chain line in FIG. 11 (position D in FIG. 11).

Next, the billet 13 delivered from the billet carrier 127 holding the billet 13 rolls and enters the billet holding portion 133 of the billet loader 111.

Next, No. 1 billet loader 111a
The swing arm 128 is pivoted upward, and the billet 13 is kept waiting at the position E which is the intermediate stop position in FIG.

When the billet loader 111 stops with the billet 13 placed at the position E and sends this stop signal to the control device 119, the temperature adjusting device 110 at the rear end of the billet is operated.

That is, since air is introduced into the piston head (not shown) of the air cylinder 118 and the piston rod 118 a is extended, the moving base 121 advances on the linear guide 117 toward the billet loader 111.

When the movable base 121 moves forward, the front end of the temperature sensor 113a of the contact type temperature sensor device 113 first comes into contact with the billet rear end 13a, and the surface temperature of the billet 13 heated to about 450 ° C. is detected. is there.

The temperature sensor 113a is connected to the billet rear end 13
Before contacting the surface of the cover 116a, the temperature sensor 113a is in a state of protruding 10 mm from the tip of the cover 116, but the temperature sensor 113a is
When the gap between the front end of the cover 116 and the rear end 13a of the billet becomes 2-3 mm, the displacement of the contact-type temperature sensor 124 is determined by the displacement sensor 124a of the displacement sensor 124. Is detected and the signal is transmitted to the control device 119, whereby the movable base 121 stops at a desired position close to the billet rear end portion 13a.

In response to the stop signal, the electromagnetic valve 120 is demagnetized so that the cooling medium, water, is conducted to the cooling water pipe 135, and from the cooling nozzle 115 toward the billet rear end 13a heated to about 450 ° C. Fine-grained water is sprayed.

When the surface temperature of the billet rear end 13a drops to a desired value, for example, a desired temperature between 200 and 350 ° C., the signal excites the electromagnetic valve 120 and stops the supply of water to the cooling nozzle 115. It is.

By the way, it takes about 20 to 25 seconds for the surface temperature of the billet rear end 13a of about 400 to 450 ° C. to drop to, for example, 200 ° C., and it is assumed that the billet has once dropped to a predetermined temperature by spraying water. Since the billet 13 is heated again by the heat capacity of the billet 13 before the billet 13 is loaded from the intermediate stop position into the container 1, it is desirable to lower the temperature to a temperature as close as possible to 200 ° C.

At the same time, the temperature sensor 11
When the output signal of the surface temperature of the billet rear end portion 13a detected at 3a is transmitted, air is introduced into the piston rod 118a side of the air cylinder 118 to move the moving base 121 to No.3. It is retracted to the original position where it does not interfere with the one billet loader 111a.

When one cycle of extrusion of the billet 13 is completed, the container 1 is retracted, the shaving device 125 cuts off the debris of the billet 13, and the extrusion stem 1
4 is retracted to the retreat limit.

Next, an intermediate stop position (position E in FIG. 11).
The billet loader 111 in the standby state with the billet 13 cooled at the rear end to the desired temperature on the ascending position rises to the extrusion center position (the F position in FIG. 11), and the subsequent extrusion stem 1
The extrusion process by the advance of No. 4 starts.

In FIG. 1, before the extrusion of the billet 13, the electromagnetic switching valve 9 is in a demagnetized state, and the vacuum pump 21 is driven to keep the vacuum tank 20 in a vacuum state of, for example, 0 to 10 Torr. When the container 1 is pulled toward the die 3 by the container cylinder 33, the protrusion 11a of the vacuum suction device 50 comes into contact with the end of the die ring 5, and the die-side end surface of the container 1 is set to the die 3 surface by, for example, about 2 to 3 mm. Is stopped in a state where the gap 6 is present.

When this operation is completed, the billet 13
The billet loader (not shown) rises with
When the extrusion stem 14 is advanced, the billet 13 is pushed into the container 1. In this state, the billet 13 is charged into the container 1 by the advance operation of the extrusion stem 14, and the front end surface of the billet 13 is inserted into the die 3. Hit it. This state is shown in FIG. At this time, the degassing space 3 of the container 1 and the billet 13
1 has air.

As for the method of vacuum suction of the air in the container 1, the billet 13 is pushed into the container 1 and the billet 1 is pressed.
The tip of the container 3 is directly pressed against the die 3 and vacuum suction is performed from the die 3 side of the container 1.

That is, as the extrusion stem 14 advances, the billet 13 is pushed into the container 1, and the cylinder 43 of the vacuum suction device 60 disposed on the extrusion stem 14 side of the container 1 is operated to activate the billet 13. The seal block 40 is closed to seal the space between the extrusion stem 14 and the container 1.

The billet 13 is pushed into the container 1, and the billet 13 contacts the die 3, and the pressure of the side cylinder (not shown) starts to rise. At the same time, the electromagnetic switching valves 9 and 46 are excited to separate the container 1 from the vacuum tank 20. Vacuum suction is performed in a state where ventilation is possible.

There are the following two methods for vacuum suction of the air in the container 1. In one method, the billet 13 is pushed into the container 1, and the tip of the billet 13 is directly pressed against the die 3 to suck the vacuum from both sides of the container 1. And vacuum suction (or vacuum degassing) from both sides of the container 1 immediately before pressing the billet 13 against the die 3.

First, the former vacuum suction method (FIG. 3) will be described. As the extrusion stem 14 advances, the billet 13 is pushed into the container 1 and disposed on the extrusion stem 14 side of the container 1. The cylinder 43 of the vacuum suction device 60 is operated to
Is closed to seal between the extrusion stem 14 and the container 1.

When the billet 13 is pushed into the container 1 and the billet 13 comes into contact with the die 3, the pressure of the side cylinder (not shown) starts to rise, and at the same time, the electromagnetic switching valves 9 and 46 are excited to connect the vacuum tank 20 to the container 1. Is made air-permeable and vacuum suction is performed.

The forward movement of the extrusion stem 14 is performed without interruption by switching from the side cylinder to the main cylinder (not shown), and the extrusion stem 14 advances to start upset. If this state is continued, the billet 1 on the extrusion stem 14 side
The air in the degassing space 31 is sucked from the die 3 side by the action of the vacuum tank 20 when the container 3 comes in close contact with the container 1.
At this time, the sucked sealed air on the side of the die 3 passes through the gap 6, passes through the deaeration hole 7 provided in a part of the seal ring 11 attached to the container 1, and from there through a pipe 8, through a pipe 8. To the electromagnetic switching valve 9.

On the other hand, the sealed air on the side of the extrusion stem 14 is supplied to a deaeration hole 4 provided in a part of the split seal block 40.
5, the liquid is sucked and discharged to the above-described vacuum tank 20 via the electromagnetic switching valve 46 on the pipe 8a.

In this way, both the deaeration hole 7 of the seal ring 11 and the deaeration hole 45 of the seal block 40 are quickly and sufficiently deaerated.

Further, the latter vacuum suction method (FIG. 4) will be described. In this case, when the discard is cut off by the shearing device after the billet 13 has been extruded, the cut surface by the shearing blade is not straight. The recessed portion (FIG. 4) is formed as if it was cut off, and an air pool is formed. When the next billet 13 is pushed out, the air in the air pool causes blisters to be trapped by the next billet 13, which is prevented. Vacuum suction method.

The inside of the vacuum tank 20 has already been
Is in a vacuum state of, for example, 0 to 10 Torr. First, the billet 13 is pushed into the container 1 as the extrusion stem 14 advances.
The tip enlarged diameter portion 49 passes through the seal block 40 and closes the seal block 40 (FIG. 4).

When the electromagnetic switching valves 9 and 46 are excited in this state, the remaining air in the container 1 starts to be vacuum-sucked by the vacuum tank 20. Then, the extrusion stem 14 is further advanced, and immediately before the tip of the billet 13 hits the die 3, the advance of the extrusion stem 14 is temporarily stopped. When the degree of vacuum in the container 1 reaches a target value, the extrusion cylinder is again operated by the side cylinder. 14 and the main cylinder (not shown) when the pressure oil in the side cylinder reaches a predetermined pressure.
The switching upset is completed.

In such a method, the previous billet 13
Even if air accumulation due to poor cutting at the time of extrusion occurs, the residual air can be completely exhausted by vacuum suction, so that the occurrence of blisters is hardly observed.

Thereafter, the extrusion stem 14 continues to advance without rest, and the billet 13 is crushed. The crushed state is shown in FIG. In these figures, the degassing space 31 between the container 1 and the billet 13 is formed by pressing the billet 13 from the extrusion stem 14 in the direction of the die 3 sequentially from S1 to S3. It can be seen from FIG. For example, deaeration is about 0
It can be performed at a degree of vacuum of 10 Torr in about 0.1 to 0.5 seconds.

After the suction and deaeration starts, the extrusion stem 14
Keeps moving forward without a break and crushes billet 13. Then, the billet 13 is filled in the container 1, and the upset is completed. Next, the extrusion is continued, and the product is extruded from the die 3. When the degassing space 31 inside the container 1 reaches a predetermined degree of vacuum, the container 1 advances to the die 3 side, and the end surface of the container 1 on the die 3 side hits the die 3 surface, and the container 3 contacts the die 3 surface. The gap 6 is set to zero, and deaeration is continued until immediately after the start of extrusion.

[0073]

As is apparent from the above description, according to the present invention, after the billet sent from the billet carrier is received by the billet loader, the billet loader is transferred to the billet loading port of the extrusion container. The intermediate stop standby position is set to about 200 to 3 while spraying a cooling medium onto the rear end of the billet during extrusion of the front billet.
After cooling to a temperature range of 00 ° C., a billet is charged into the extrusion container suspended by a suspension mechanism before the extrusion container is brought into contact with a die, and a seal block is formed on an end surface of the extrusion container on the extrusion stem side. With the billet closed with respect to the extrusion stem being pressed, air accumulated on the extrusion stem side in the container is evacuated from both the die side and the extrusion stem side before starting to extrude the billet. By doing so, the space between the container and the extrusion stem and the space between the container and the die can be sealed, and the air in the container can be reliably and easily degassed. Therefore, an extruded product without air entrapment can be easily obtained. Further, even after reaching a predetermined degree of vacuum and performing container sealing, deaeration from the die side is continued until immediately after the start of extrusion, so that there is no danger that air will flow back from the sealing surface and enter again. Further, the metal flow in the billet during the extrusion can be suppressed, the extruded material having no blister can be extruded stably, and the yield of the extruded material of the product can be greatly improved.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing one embodiment of a degassing system for an extrusion container according to the present invention.

FIG. 2 is a front view as viewed from A to A in FIG. 1;

FIG. 3 is an explanatory view illustrating that a tip of a billet is pressed against a die and then vacuum suction is performed from both containers.

FIG. 4 is an explanatory view illustrating vacuum suction from both sides of a container immediately before pressing a billet tip against a die.

FIG. 5 is a front view as viewed from BB in FIG. 1;

FIG. 6 is an enlarged sectional view of a main part of a suction unit for sucking air through a minute space between a die and a container.

FIG. 7 is a schematic diagram of a billet rear end temperature adjusting device according to the present invention.

8 is a cross-sectional view of a main part of the temperature adjustment device shown in FIG.

FIG. 9 is a front view of an extrusion press provided with a temperature control device at the rear end of the billet.

FIG. 10 is a front view of a billet loader.

FIG. 11 is a configuration diagram of a billet loader.

FIG. 12 is a conceptual diagram showing how a billet pressed in a container is crushed.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 container 2 container tire 3 die 6 gap 7 deaeration hole 9 electromagnetic switching valve 10 outer ring 11 seal ring 11 a projection 12 spring 13 billet 14 extrusion stem 16 tubular member 17 dami block rear member 18 outer ring 20 vacuum tank 21 vacuum pump 23 Heat-resistant sealing material 25 Seal plate 30 Temporary stop mechanism 31 Deaeration space 40 Seal block 41 Seal packing 42 Guide plate 43 Cylinder 45 Deaeration hole 46 Electromagnetic switching valve 49 Large diameter portion 50, 60 Vacuum suction device 70 Fix dummy block 110 Billet Rear end temperature control device 111 Billet loader 113 Contact temperature sensor device 113a Temperature sensor 115 Cooling nozzle 116 Cover 118 Air cylinder 119 Control device 120 Electromagnetic valve 121 Move Base 124 Displacement sensor device 124a Displacement sensor 126 Billet loading port 127 Billet carrier 128 Swing arm 131 Mounting table 133 Billet holding unit

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. ⁷ , DB name) B21C 29/00 B21C 27/04 B21C 33/00

Claims (1)

(57) [Claims] After receiving a billet sent from a billet carrier by a billet loader, an intermediate stop standby position of the billet loader is provided in the middle of transferring the billet to a billet loading port of an extrusion container. About 200 to 30 while spraying the cooling medium on the rear end of the billet
After cooling to a temperature range of 0 ° C., a billet is charged into the extrusion container suspended by a suspension mechanism before the extrusion container is brought into contact with a die, and a sealing block is formed on the extrusion stem side end surface of the extrusion container. With the billet closed with respect to the extrusion stem being pressed, air accumulated on the extrusion stem side in the container is evacuated from both the die side and the extrusion stem side before starting to extrude the billet. An extrusion molding method characterized in that: