JP2001334355A - Method for producing blank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a forging blank at a low cost. SOLUTION: In a forming apparatus, a gate valve 28 is arranged in a communicating passage 26 between a tundish 16 and a mold 20. The gate valve 28 is provided with a sliding plate 52, and the sliding plate 52 is shifted to an opening position and a shut-off position by driving a hydraulic cylinder 64. A starting member 80 is disposed so as to be shiftable in the axial direction of the mold 20 at the back side of the mold 20. The retreating quantity of the starting member 80, i.e., the length in the axial direction of a cast block 36 formed in the mold 20 and drawn out with the starting member 80 is detected with a stroke sensor 86, and when the length in the axial direction reaches a setting value, a change-over device 70 is changed over to close the gate valve 28. After fully solidifying the cast block 36 in the mold 20, the gate valve 28 is opened again and this solidified cast block 36 is used as the starting member to form the following cast block 36. In such a way, the bar-like cast block group which mutually adheres but is not integrally combined, is obtained, and the cast blocks 36 are separated one by one to obtain plural pieces of forging blanks.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a material for producing a product, such as a material to be forged into a desired forged product or a material to be cut into a cut product. .

[0002]

2. Description of the Related Art The production of a forged material by a continuous casting method is disclosed in Japanese Patent Application Laid-Open Nos. 3-155436 and 3-26.
It is already known from JP-A-8844. The continuous casting method is a method of manufacturing a rod by pouring a molten metal from a tundish into a cylindrical mold, solidifying the molten metal therein, and sequentially pulling out the resulting ingot from the mold.
The forged material is manufactured by cutting this bar into a predetermined length, but the cost is high, and the material yield is reduced due to the cutting allowance and the generation of offcuts. There was a problem. Furthermore, a long bar is apt to warp, and it may be necessary to perform straightening prior to cutting, in which case the manufacturing cost is further increased. In the above, the forging material has been described. However, a similar problem exists when the material is for manufacturing a cut product.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to reduce the cost of manufacturing a material.
In the material manufacturing method according to the present invention, the molten metal is poured from the tundish into the mold through the gate valve, and the ingot formed in the mold is drawn out.When the ingot reaches a desired length, the gate valve is closed. Wait for all the molten metal in the mold to solidify, open the gate valve again after solidification, start casting the next molten metal using the previously solidified ingot as a start member, A plurality of materials are obtained by separating at the boundary surface.

[0004] Although a plurality of ingots produced by this method are fixed to each other at the boundary surface, since they are not continuous long materials, they can be relatively easily separated into individual ingots. it can. For example, another ingot is clamped by a clamping device, and one ingot is protruded from the clamped ingot in a cantilever manner. Can be separated from other ingots. Further, the present invention is applicable to the manufacture of a material or the like made of a material mainly composed of iron, but is particularly suitable for the manufacture of a material made of a material mainly composed of aluminum. The cross-sectional shape of the material may be a simple circle, rectangle, or the like, or may be a shape close to the cross-sectional shape of a forged product or a cut product.

According to the present invention, a plurality of ingots can be easily separated, and no chips are generated during the separation. In addition, since a bar having a predetermined length is not cut into a material having a desired length, no scrap is generated. From these points, it is possible to greatly reduce the manufacturing cost of a relatively short material.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to the production of a forging material for a piston for a swash plate type compressor will be described below in detail with reference to the drawings. FIG. 1 shows a forming apparatus used in the forged material manufacturing method according to the present embodiment. As shown in FIG. 2, the forging material 12 having a columnar shape with a certain length is manufactured by the present forming apparatus. This molding machine
It has the same configuration as the continuous casting machine used in the continuous casting method, and has a container-like shape in which a molten metal 14 (in this embodiment, aluminum alloy) poured from a ladle (not shown) is housed. 16 and a mold 20 horizontally connected to the tundish 16. Specifically, an inlet 22 formed in the vicinity of the bottom of the tundish 16 and one opening 24 of the generally cylindrical mold 20 are communicated with each other by a communication passage 26, and in the middle of the communication passage 26. A gate valve 28 for opening and closing the communication passage 26 is provided.
The communication with the internal space 0 is interrupted.

The mold 20 is a water-cooled hollow cylindrical mold, and a cooling chamber 32 through which cooling water flows is formed in a circumferential direction inside the peripheral wall. The cooling chamber 32 is connected to a cooling water supply device via a cooling water supply passage (not shown). A cooling water discharge port 34 is formed in the peripheral wall of the mold 20 at an end opposite to the tundish 16 side in the axial direction of the mold 20 and communicates with the cooling chamber 32. The cooling water inside is discharged from the cooling water discharge port 34 toward the outer peripheral surface of the ingot 36 formed into a column shape in the mold 20. Note that a cooling gas (eg, nitrogen gas) may be injected instead of the cooling water. On the inner peripheral surface of the mold 20, a graphite layer 40 having self-lubricating properties is formed,
Seizure of the molten metal on the mold 20 is prevented.

The gate valve 28 is connected to the tundish 16
And a slide plate 52 slidably held inside the support member 50. The support member 50 is formed with a through-hole penetrating in the thickness direction (in the present embodiment, in the horizontal direction), and the through-hole forms the communication path 26. Tundish 1 with through hole
The end on the 6 side has a square cross section and the mold 2
The cross-sectional shape of the end on the 0 side is a circle having a diameter slightly larger than the length of the diagonal of the square at the end on the tundish 16 side. The graphite layer 40 has reached the inside of this circular section, and the outer diameter of the ingot 36 is defined by the inner peripheral surface of the graphite layer 40.

The supporting member 50 has a sliding hole 58 extending in a direction perpendicular to the thickness direction (in the vertical direction in the present embodiment) and communicating with the communication passage 26.
The sliding plate 52 is fitted slidably in the up-down direction. A piston rod 66 of a hydraulic cylinder 64 is fixed to an end of the sliding plate 52 opposite to the communication passage 26 side. The hydraulic cylinder 64 is a type of a hydraulic cylinder that constitutes a moving device that moves the sliding plate 52. When the hydraulic cylinder 64 is driven, the sliding plate 52 has an end on the opposite side to the side connected to the piston rod 66 and the communication passage 2.
6 is opened to form a part of the inner peripheral surface of one end of the through hole having a square cross section together with the supporting member 50, and a blocking position for blocking communication between the inlet 22 and the internal space of the mold 20. And moved to. The expansion and contraction of the piston rod 66 of the hydraulic cylinder 64 is switched by the switching device 70. The switching device 70 preferably includes, for example, an electromagnetic control valve, and a state in which hydraulic oil from a tank (not shown) is supplied to one hydraulic chamber of the hydraulic cylinder 64 and discharged from the other hydraulic chamber. Is supplied to the hydraulic chamber of
The state is switched between a state of being discharged from one hydraulic chamber and a holding state.

[0010] Behind the mold 20 on the side opposite to the tundish 16 side (right side in FIG. 1), a start member 80 is provided.
Is provided so as to be movable in the axial direction of the mold 20, and is moved by a moving device (not shown). Start member 8
At the time of starting the operation of the molding apparatus, 0 is fitted into the mold 20 and is located at the forward end position close to the communication path 26. In the present embodiment, a hydraulic cylinder, which is a type of hydraulic cylinder, is used as the moving device, and the piston rod 84 of the hydraulic cylinder is connected to the end of the start member 80 on the opposite side to the tundish 16 side. I have. The hydraulic cylinder is provided with a stroke sensor 86 for detecting the amount of movement of the piston rod 84 and, consequently, of the start member 80, and detects the amount of retreat of the start member 80 from the forward end position. If the retreat amount of the start member 80 is known, the axial length of the ingot 36 formed and drawn in the mold 20 can be known. Stroke sensor 86
Is an example of a detection device that detects that the formed ingot 36 has reached a desired axial length.

The molding apparatus is controlled by a controller 90. The control device 90 is mainly composed of a computer. The stroke sensor 86 and the like are connected to an input unit of the control device 90, and the switching device is connected to an output unit of the control device 90 via a drive circuit (not shown). 70 and the like are connected. Accordingly, if the stroke sensor 86 detects that the ingot 36 has reached the desired length and the detection signal is supplied to the control device 90, the switching device 70 is switched and the sliding plate 52 is opened. The tundish 16 is moved from the position to the blocking position, and the communication between the inside of the tundish 16 and the inner space of the mold 20 is blocked.

A method for producing a forged material using the molding apparatus configured as described above will be described. First, the molten metal 14 of the aluminum alloy is supplied to the tundish 16 from the ladle with the sliding plate 52 in the shut-off position.
Further, the start member 80 is positioned at the forward end position. When the amount of the molten metal 14 in the tundish 16 exceeds the set amount, the gate valve 28 is opened, and the molten metal 14 of the aluminum alloy can be poured from the tundish 16 into the mold 20 through the communication path 26. Thereafter, if the start member 80 is retracted by contracting the piston rod 84, the volume in the mold 20 increases, and the molten metal 14 is injected into the mold 20 accordingly. The molten metal 14 is cooled by the mold 20 via the graphite layer 40 and solidified by being cooled by the start member 80. However, since the graphite layer 40 has a self-lubricating property, the solidified ingot 36 To the start member 80
Is pulled out of the mold 20 with the retreat. Since the drawn ingot 36 is cooled by the water discharged from the cooling water discharge port 34, heat is taken from the molten metal 14 via the start member 80, so that the molten metal 14
0 and the portion near the mold 20 is solidified in order,
Grows. When the stroke sensor 86 detects that the start member 80 has been retracted by the set amount, the gate valve 28 is closed, and the supply of the molten metal 14 from the tundish 16 to the mold 20 is stopped. In a state in which the molten metal 14 is not supplied to the mold 20,
4 is solidified and waits for a set time until the ingot 36 has a predetermined length.

After a lapse of a set time, the start member 80 is retracted by a small distance, and in a state where the ingot 36 is separated from the slide plate 52, the contraction of the piston rod 66 causes the slide plate 52 to move to the open position. Moved. Thereby, injection of the molten metal 14 from the tundish 16 to the mold 20 is allowed again. Thereafter, the piston rod 84 is contracted. At this time, as shown in FIG. 3, the first ingot 36 functions as a start member 80, and the molten metal 14 from the tundish 16 adheres to the surface of the first ingot 36 facing the molten metal surface, As described above, solidification is sequentially performed from a portion near the ingot 36 as a start member. In this way, the previously solidified ingot 36 functions as a starting member for forming the next ingot 36, and finally, a plurality of ingots 36 having a predetermined length are formed at the end faces adjacent to each other. It is formed as a bar-shaped ingot group that is fixed at a certain boundary surface 102. The number of ingots 36 constituting the bar-shaped ingot group is limited by the axial length of the ingot 36 and the maximum stroke of the piston rod 84.

The plurality of ingots 36 formed as described above are separated from each other at the boundary surface 102. The separation operation is performed, for example, by the method shown in FIG. First, if the outer peripheral surface of the ingot 36 adjacent to the ingot 36 located at the extreme end is clamped from both sides by the pair of gripping claws 112 and 114 of the clamp device 110, the ingot 36 located at the extreme end is Is in a cantilevered state. In the present embodiment, the gripping claws 112 are provided at a fixed position, and the gripping claws 114 are provided so as to be movable in the vertical direction. With the outer peripheral surface of the ingot 36 supported on the bottom surface of the V-groove of the gripper 112, the gripper 114 having the same V-groove is moved toward and away from the ingot 36, thereby holding the ingot 36. , Is released. And the ingot 3 located at the above-mentioned end
In the case of this embodiment, the impact is applied from the upper side to the lower side by the hammer member 120 attached to the ram of the press machine constituting the separating device, so that the ingot 36 Separated from clumps. Although the boundary surfaces 102 are fixed to each other, they are not joined together, so that if an impact is applied to one of the ingots 36, the ingots can be separated from the other ingot 36. In this way, the endmost ingot 36 of the bar-shaped ingot group is sequentially separated, and a plurality of forging materials 12 having a desired length are obtained.

According to this embodiment, a forged material 12 having a desired length can be manufactured at low cost. Compared to the conventional method of manufacturing a forged material by cutting a continuously cast long bar into a desired length, the cost and time required for the cutting process can be omitted.
It is possible to produce a forged material inexpensively and efficiently without wasting scraps and the like. Further, in the case of the conventional long bar, warpage is likely to occur, and it is necessary to correct this warp before cutting. However, in the present embodiment, this straightening step is also unnecessary, and this also leads to a reduction in manufacturing cost. Can be reduced.

Instead of the stroke sensor 86, the detecting device may be, for example, an imaging device. The boundary between the start member 80 and the ingot 36 and the ingot 36
The ingot 3 is determined based on the difference in optical characteristics such as brightness and color between the boundary between the ingots and the outer peripheral surfaces of the ingot 36 and the start member 80.
6 to detect that the ingot 36 has reached the predetermined length.

Although the embodiments of the present invention have been described in detail above, these are merely examples, and the present invention has been described in the section [Problems to be Solved by the Invention, Means for Solving Problems and Effects]. Various modifications and improvements can be made based on the knowledge of those skilled in the art including the embodiments.

[Brief description of the drawings]

FIG. 1 is a front sectional view showing a main part of a forming apparatus for carrying out a forged material manufacturing method according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a forged material manufactured by the forged material manufacturing method.

FIG. 3 is a view for explaining one step of the forging material manufacturing method.

FIG. 4 is a diagram for explaining another process of the forged material manufacturing method.

[Explanation of symbols]

12: Forged material 14: Molten metal 16: Tundish 20: Mold 28: Gate valve 36: Ingot 52: Sliding plate 102: Boundary surface 110: Clamp device 112, 114: Gripping claw 120: Hammer member

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (Reference) B22D 11/126 B22D 11/126 K

Claims (1)

[Claims] 1. A molten metal is poured from a tundish into a mold via a gate valve, an ingot formed in the mold is drawn out, and when the ingot reaches a desired length, the gate valve is closed and the mold in the mold is closed. Wait for all the molten metal to solidify, open the gate valve again after it has solidified, start casting the next molten metal with the first solidified ingot as a start member, and then separate the successive ingots at their interface A method for producing a plurality of materials.