JP2002086236A - Forging apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a forging apparatus capable of reducing a heat transfer from a die to a die base and a machine body and improving a forming precision and durability of a forging in warm forging or in hot forging formed at a high temperature. SOLUTION: In the forging apparatus including dies 11, 21 having a heating means and die bases 15, 25 which fix these dies and have a cooling means mounted to the machine body, heat insulation materials 18, 28 of compression strength of >=400 N/mm2 are interposed between the dies 11, 21 and the die bases 15, 25. Further, die holders 17, 27 are interposed between the dies and die bases, heat insulation materials 16, 26 of compression strength of >=400 N/mm2 are interposed between the dies and the die holder and between the die holders 17, 27 and the die bases. The heat insulation material preferably has a strain quantity of <=0.5%, a heat resistance temperature of >=473 K, compression strength at 473 k of >=350 N/mm2, a heat expansion rate vertical to a thickness direction of <=3×10-5/K and a thermal conductivity rate of <=0.35 W/(m/K).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a forging apparatus including a mold having a heating means, and a die base fixed to the mold and attached to an airframe and having a cooling means.

[0002]

2. Description of the Related Art In the forming of an aluminum alloy or a magnesium alloy by warm or hot forging, the forming temperature is 473K.
For this reason, it is necessary to heat and maintain the forging material and the mold at a specific temperature. On the other hand, prevention of a reduction in molding accuracy due to heat expansion from heat transfer from a mold held and held to a part other than the mold or to a machine body is also performed. For example,
No. 157554 discloses that a heat insulating material is interposed between a die base for holding a forging die and cooling water is circulated in the die base to prevent heat from the heated and held die from being transmitted to the forging equipment. There is a description to do.

As shown in FIG. 2, Japanese Utility Model Laid-Open No. 59-89636 discloses an arrangement in which a pair of cooling plates 54 fixed to respective airframes 51 and 52 and having cooling water circulation passages 53 provided therein are provided. In addition, a plurality of grooves 55 are provided on the contact surface with the cooling plate 54, a heating plate 57 having a heat source 56 therein is superposed, and a mold 58a,
There is a description of a forging device integrally attached with 58b. Note that, since the above-described configuration fixed to each of the airframes 51 and 52 is almost the same, reference numerals are mainly given to the airframe 51 side in FIG. Japanese Utility Model Application Laid-Open No. 59-89636 discloses that the deformation of the heat-insulating material, which is inferior to that of Japanese Utility Model Application Laid-Open No. 51-157554, causes inconsistency in the parallelism and position of the upper and lower dies, resulting in accurate molding. There is a statement that it is difficult. According to the invention disclosed in Japanese Utility Model Laid-Open Publication No. 59-89636, not only the heat transfer to the cooling plate 54 can be suppressed as small as possible without intervening the heat insulating material, but also
No heat insulating material is required between the molds 1 and 52, so that accurate molding operation can always be maintained without displacement of the mold.

[0004]

SUMMARY OF THE INVENTION The present inventors have disclosed a forging apparatus including a mold having a heating means and a die base having the mold fixed thereto and having a cooling means attached to an airframe. Intensive research was carried out including the techniques described in JP-A-157554 and JP-A-59-89636. According to the present inventors, Japanese Utility Model Laid-Open No. 51-157
In the case of an ordinary easily deformable heat insulating material as described in Japanese Patent Application Laid-Open No. 554, it is easy for the parallelism and the position of the upper and lower dies to be out of order. On the other hand, even if a large number of grooves 55 are provided on the contact surface between the cooling plate 54 and the heating plate 57 as described in Japanese Utility Model Laid-Open No. In the case of warm forging or hot forging in which heat is transferred to the cooling plate 54, the die base integrated with or separate from the cooling plate 54 is also extended by the transfer of heat to the cooling plate 54, and the forming accuracy of the forged product is increased. And the deterioration of the durability of the forging device may be a problem.

[0005] The present invention provides a forging that can improve the molding accuracy and durability of a forged product by reducing heat transfer from a die to a die base and a body even in warm forging or hot forging formed at a high temperature. To get the equipment.

[0006]

In order to solve the above-mentioned problems, the present invention is directed to a forging apparatus including a mold having a heating means, and a die base fixed to the mold and attached to an airframe and having a cooling means. Further, a heat insulating material having a compressive strength of 400 N / mm ² or more is interposed between the mold and the die base. The present invention is also a forging apparatus including a mold having a heating means, and a die base fixed to the mold and attached to a machine body and having a cooling means, wherein a mold holder is provided between the mold and the die base. And a heat insulating material having a compressive strength of 400 N / mm ² or more between the mold and the mold holder and between the mold holder and the die base. Here, the heat insulating material preferably has a strain amount of 0.5% or less, a heat resistance temperature of 473K or more, and a compressive strength at 473K of 350%.
N / mm ² or more, thermal expansion coefficient perpendicular to the thickness direction is preferably 3 × 10 ⁻⁵ / K or less, and thermal conductivity is 0.35 W / (m · K) or less. Preferably, there is.

The heat insulating material reduces the heat transfer from the heated mold to the die base and further reduces the heat transfer to the body by the die base provided with the cooling means. When the compressive strength of the heat insulating material is set to 400 N / mm ² or more, and preferably, the strain amount of the heat insulating material is set to 0.5% or less, the area of the heat insulating material is secured so that the forming load is continuously applied. Even so, the deformation of the heat insulating material can be made very small, and accurate molding can be performed without causing any inconsistency in the parallelism and position of the upper and lower dies. The heat-resistant temperature of the heat insulating material is 473K or more, the compressive strength at 473K is 350N / mm ² or more, or the thermal expansion coefficient perpendicular to the thickness direction of the heat insulating material is 3 × 10 ^-5.
If it is / K or less, for example, even if forging a magnesium alloy or an aluminum alloy at a forging temperature of around 473K, the durability of the heat insulating material can be ensured, and the elongation in the thickness direction of the heat insulating material is small, so that the forming accuracy can be ensured. . When the thermal conductivity of the heat insulating material is 0.35 W / (m · K) or less, heat transfer from the heated mold to the mold holder and / or the die base is reduced, and the forging device is excellent. Is kept.

[0008]

Embodiments of the present invention will be described below. FIG. 1 is a sectional view of a main part of a forging apparatus for hot forging a magnesium alloy. In the forging device shown in FIG.
1 and the upper mold 21 are formed as a pair. Since the lower mold 11 side and the upper mold 21 side are almost the same except that the punch part 11a and the die part 21a are different, the lower mold 11 side will be described as a representative here. A heat insulating material 16 is provided on a die base 15 fixed to the body 13 and provided with a cooling water circulation channel 14 therein, and a mold holder 17 is mounted on the heat insulating material 16. A heat insulating material 18 is interposed in the mold holder 17 and the mold 11 which is heated to 473K by the heater 19 is attached.

The heat insulating materials 16 and 18 have a compressive strength of 400N.
/ Mm ² or more, strain amount 0.5% or less, compressive strength at 473K is 350N / mm ² or more, heat resistance temperature is 573K
As described above, the thermal expansion coefficient perpendicular to the thickness direction is 3 × 10 ⁻⁵ / K or less, and the thermal conductivity is 0.35 W / (m · K) or less. Specifically, using "ROSNABOARD" (trade name of Nikko Kasei Co., Ltd.), the compressive strength is 440 N / mm ² , the strain amount is 0.5% or less, and the compressive strength at 473K is 430 N / mm.
^{2. The} heat resistance temperature is 673K, the thermal expansion coefficient perpendicular to the thickness direction is 2.6 × 10 ^-5 / K or less, and the thermal conductivity is 0.21 W / (m
・ K).

The heat insulating materials 16 and 18 reduce the heat transfer from the heated lower mold 11 to the die base 15, and further reduce the heat transfer to the body 13 by the die base 15 provided with the cooling water circulation passage 14. . Then, the compressive strength of the heat insulating materials 16 and 18 is set to 440 N / mm ² or more,
By securing the area of the heat insulating materials 16 and 18, even if a molding load is continuously applied, the deformation of the heat insulating materials 16 and 18 becomes very small, and the parallelism and the position of the lower mold 11 and the upper mold 21 are reduced. Accurate molding can be performed without any irregularities. Also,
Since the heat-resistant temperature of the heat insulating material is set to 673K, the durability of the heat insulating materials 16 and 18 can be ensured even when forging a magnesium alloy or an aluminum alloy at a forging temperature of around 473K. Since the thermal expansion coefficient of the heat insulating materials 16 and 18 in the thickness direction is set to 2.6 × 10 ^-5 / K,
Elongation in the thickness direction of 18 is small and molding accuracy can be secured.
The thermal conductivity of the heat insulating materials 16 and 18 is set to 0.21 W / (m
K) Since it is not more than the above, the heat transfer from the heated mold to the mold holder 16 and / or the die base 15 is reduced, and the forging device can be kept good.

[0011]

The forging apparatus of the present invention insulates a die and a die base and reduces the heat transfer to the die base even in warm forging or hot forging performed at a high temperature to form a forged product. Accuracy and durability of forging equipment can be improved.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of a forging device according to an embodiment.

FIG. 2 is a sectional view of a main part of a forging device described in Japanese Utility Model Laid-Open No. 59-89636.

[Explanation of symbols]

 Reference Signs List 11 lower die 11a die part 13,23 body 14,24 cooling water circulation flow path 15,25 die base 16,18,26,28 heat insulator 17,27 die holder 19,29 heater 21 upper die

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Mamoru Suka 684-1 Fukamachi, Oukamachi, Minamiuonuma-gun, Niigata Pref. Inside the Tokyo Fine Forging Works Co., Ltd. Muikamachi Plant (72) Inventor Hiroshi Watanabe Minato-ku, Tokyo 1-2-1 Shibaura Hitachi Metals Co., Ltd. (72) Inventor Atsuto Seki 1-2-1 Shibaura Minato-ku, Tokyo Hitachi Metals Co., Ltd. (72) Inventor Baoo Hama Kinuigaoka, Moka-shi, Tochigi 11 F-term in Hitachi Metals, Ltd. Materials Research Laboratory 4E087 AA08 ED13 ED16 4E090 DA01 DA09 HA05

Claims (6)

[Claims] 1. A forging apparatus comprising a mold having heating means, and a die base fixed to the mold and attached to an airframe and having cooling means, wherein a compression strength between the mold and the die base is 400N. A forging device comprising a heat insulating material of at least / mm ² . 2. A forging apparatus comprising: a mold having heating means; and a die base fixed to the mold and attached to a machine body and having a cooling means, wherein a mold holder is interposed between the mold and the die base. And a compression strength of 40 between the mold and the mold holder and between the mold holder and the die base.
A forging device comprising a heat insulating material of 0 N / mm ² or more. 3. The forging device according to claim 1, wherein the heat insulating material has a strain amount of 0.5% or less. 4. The forging apparatus according to claim 1, wherein the heat-insulating material has a heat-resistant temperature of 473K or more and a compressive strength at 473K of 350 N / mm ² or more. 5. The forging apparatus according to claim 1, wherein the thermal insulator has a coefficient of thermal expansion perpendicular to the thickness direction of 3 × 10 ⁻⁵ / K or less. 6. The forging apparatus according to claim 1, wherein the heat insulating material has a thermal conductivity of 0.35 W / (m · K) or less.