Heating and heat preservation device of aluminum alloy isothermal forging die

Abstract

The utility model discloses a heating and heat preservation device of an aluminum alloy isothermal forging die, which comprises a lower die block and an upper die block arranged at the top of the lower die block, an upper die heat insulation base plate for insulating heat of the upper die block is arranged at the top of the upper die block, and a heat insulation plate for insulating heat of the lower die block is arranged at the bottom of the lower die block. In order to improve the heat balance speed and efficiency, high-thermal-conductivity die steel is selectively adopted to manufacture the upper die and the lower die of the cavity, in order to reduce the invalid heat energy consumption of an isothermal die and block or reduce the heat energy loss path, a heat insulation material is adopted to wrap a coil and the die on the outer layer of the die, and the contact and heat exchange between the outer surface of the die and air are reduced; under the condition that the necessary temperature of isothermal forging is guaranteed, the input energy of induction heating is reduced, the production cost is reduced, high-thermal-conductivity die steel is adopted between an induction heating coil and a module or a combined module of the die, and the heat balance speed and efficiency of the module are improved.

Description

Technical Field

[0001] This utility model relates to the field of hot forming technology for substation fittings, specifically a heating and heat preservation device for an aluminum alloy isothermal forging die. Background Technology

[0002] Isothermal forging is an effective method for achieving superplastic forming of difficult-to-form metals and light alloys. Isothermal forging requires the die to be heated to the forging temperature range of the workpiece and maintained at a high temperature. For hot forging of aluminum and magnesium alloys, the die temperature is relatively low; at the initial forging temperature, the die surface temperature can reach 400–500°C, and there is a problem of uneven die heating. This problem is particularly prominent for complex cavities and large-sized dies, as the die temperature inevitably changes with the forging closing time.

[0003] Existing heating methods for isothermal forging dies typically involve installing heating devices inside and outside the upper die and inside and outside the lower die, respectively, which are fixed to the press's upper beam and worktable along with the die base. Heating rods can be embedded in the upper and lower dies to heat the upper and lower modules separately. Alternatively, induction heating coils can be installed inside the upper and lower modules, or induction heating can be performed by installing induction coils around the die exterior.

[0004] Existing mold heating systems suffer from low response due to the influence of mold structure and the thermal conductivity of mold materials, resulting in an inability to effectively adjust to temperature changes in the mold cavity. This significant lag in control leads to uncontrolled changes in heat demand during production, such as the entry of blanks into the mold cavity, the exit of parts, and the emptying of the mold cavity, resulting in overheating or underheating. Therefore, we need to propose a heating and insulation device for aluminum alloy isothermal forging molds. Utility Model Content

[0005] The purpose of this invention is to provide a heating and heat preservation device for an isothermal forging die of aluminum alloy. To improve the speed and efficiency of thermal equilibrium, high thermal conductivity die steel is selectively used to manufacture the upper and lower dies of the cavity. To reduce ineffective heat energy consumption of the isothermal die and block or reduce heat loss paths, heat insulation material is used to wrap the induction coil and the die on the outer layer of the die, reducing the contact and heat exchange between the outer surface of the die and the air. While ensuring the necessary temperature for isothermal forging, the input energy of induction heating is reduced, and production costs are lowered. High thermal conductivity die steel is used between the heating coil and the die modules or combined modules to increase inward heat conduction and maintain the die temperature, thus solving the problems mentioned in the background art.

[0006] To achieve the above objectives, this utility model provides the following technical solution:

[0007] A heating and heat preservation device for an aluminum alloy isothermal forging die includes:

[0008] The lower module, and the upper module located at the top of the lower module;

[0009] The upper module is provided with a heat insulation pad for heat insulation at the top, and the lower module is provided with a heat insulation plate for heat insulation at the bottom.

[0010] The upper module is surrounded by an upper mold induction heating coil for heating the upper module, and the lower module is surrounded by a lower mold induction heating coil for heating the lower module.

[0011] Preferably, the top of the upper mold heat insulation pad is provided with an upper mold base with cooling water channels, and the upper mold heat insulation pad is located between the upper mold base with cooling water channels and the upper module.

[0012] Preferably, the bottom of the heat insulation plate is provided with a lower mold base with cooling water channels, and the heat insulation plate is located between the lower mold base with cooling water channels and the lower module.

[0013] Preferably, the upper module and the lower module each have a mold cavity on their opposite sides, and the two sets of mold cavities have the same shape.

[0014] Preferably, both the upper and lower modules are made of CP2M mold steel.

[0015] Preferably, the inner cavity of the upper module is equipped with two sets of upper mold temperature sensors and wiring channels, one set of upper mold temperature sensors and wiring channels being close to the mold cavity, and the other set of upper mold temperature sensors and wiring channels being close to the outer surface of the upper module.

[0016] Preferably, the inner cavity of the lower module is equipped with two sets of lower mold temperature sensors and wiring channels, one set of which is close to the mold cavity, and the other set is close to the outer surface of the lower module.

[0017] Preferably, both the upper mold heat insulation pad and the heat insulation plate are made of pressure-resistant high-temperature heat insulation material.

[0018] Compared with the prior art, the beneficial effects of this utility model are:

[0019] 1. In order to improve the speed and efficiency of thermal equilibrium, this utility model selectively uses high thermal conductivity mold steel to manufacture the upper and lower dies of the cavity. In order to reduce the ineffective heat energy consumption of the isothermal mold and block or reduce the path of heat energy loss, heat insulation material is used to wrap the induction coil and the mold on the outer layer of the mold to reduce the contact and heat exchange between the outer surface of the mold and the air. Under the condition of ensuring the necessary temperature for isothermal forging, the input energy of induction heating is reduced, and the production cost is reduced. High thermal conductivity mold steel is used between the induction heating coil and the module or combination module of the mold to increase the inward heat conduction in order to maintain the temperature of the mold.

[0020] 2. This utility model uses high thermal conductivity mold steel to manufacture the mold cavity, improving the heat conduction between the induction heating coil and the mold. A heat-insulating coating and wrapping is applied to the outer layer of the mold to reduce heat dissipation from the outer surface. A pressure-resistant, high-temperature insulating material pad is used between the module and the mold base to block heat conduction between mold structures, accelerating temperature balance in the mold cavity and preventing forming defects caused by uneven forming temperature in the forming blank. The induction coil is located on the outer layer of the mold, facilitating maintenance and replacement. It has strong versatility and does not change the internal structure and design principles of the mold. Except for a slight increase in the cost of the heat-conducting mold material, other processing and materials remain unchanged, resulting in minimal cost variation, but significantly improved product quality stability. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of heat dissipation in isothermal forging dies;

[0022] Figure 2 This is a schematic diagram of the induction heating isothermal mold of this utility model.

[0023] In the diagram: 10. Lower mold base with cooling water channels; 11. Heat insulation plate; 12. Lower mold induction heating coil; 13. Mold cavity; 14. Upper mold induction heating coil; 15. Upper mold temperature sensor and wiring channel; 16. Upper mold base with cooling water channels; 17. Upper mold heat insulation pad; 18. Upper module; 19. Lower module; 20. Lower mold temperature sensor and wiring channel. Detailed Implementation

[0024] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0025] The device described in this invention is suitable for forging 5xxx, 6xxx, and 7xxx series aluminum alloys. A typical forging material is 6082, the initial forging temperature is 470°C, and the die preheating temperature is 390–420°C.

[0026] Please see Figure 1-2 This utility model provides a technical solution:

[0027] A heating and heat preservation device for an aluminum alloy isothermal forging die includes:

[0028] The lower module 19, and the upper module 18 disposed on top of the lower module 19;

[0029] The top of the upper module 18 is provided with an upper mold heat insulation pad 17 for heat insulation of the upper module 18, and the bottom of the lower module 19 is provided with a heat insulation plate 11 for heat insulation of the lower module 19.

[0030] The upper module 18 is surrounded by an upper mold induction heating coil 14 for heating the upper module 18, and the lower module 19 is surrounded by a lower mold induction heating coil 12 for heating the lower module 19.

[0031] By adding heat insulation material between the module and the mold base, heat conduction from the module to the mold base is blocked, reducing the heat loss rate of the module. The thermal conductivity of non-metallic heat insulation material is about 0.3 W / MK, only 1.07% of that of steel. Therefore, it can greatly reduce the heat conduction of the mold structure. By wrapping the coil and the mold with heat insulation material on the outer layer of the mold, the contact and heat exchange between the outer surface of the mold and the air are reduced. Experiments show that wrapping the induction coil with heat insulation coating, at the thinnest possible thickness, reduces radiative heat loss by 40%-65% compared to direct exposure. After adopting this utility model, the effective power of the medium frequency induction heating power supply is reduced from 22 kW to 14.5 kW, a reduction of about 34%. Under the condition of ensuring the mold temperature of isothermal forging, energy saving and consumption reduction are achieved.

[0032] The upper mold heat insulation pad 17 is provided with an upper mold base 16 with cooling water channels on its top. The upper mold heat insulation pad 17 is located between the upper mold base 16 with cooling water channels and the upper module 18.

[0033] The upper mold heat insulation pad 17 is located between the upper mold base 16 with cooling water channels and the upper module 18, which can more effectively isolate the high temperature generated by the upper module 18, and at the same time bring the cooling water channels closer to the heat source, thereby improving the cooling efficiency. Through the heat insulation effect of the upper mold heat insulation pad 17, the temperature distribution of the mold can be optimized, making the cooling more uniform and improving the product quality.

[0034] The bottom of the heat insulation plate 11 is provided with a lower mold base 10 with cooling water channels, and the heat insulation plate 11 is located between the lower mold base 10 with cooling water channels and the lower module 19.

[0035] The lower mold base at the bottom of the heat insulation plate 11 has cooling water channels, which can directly cool the heat insulation plate 11, improve cooling efficiency, and ensure temperature control during the production process. The heat insulation plate 11 is located between the lower mold base and the lower module 19, which can avoid direct contact with the high-temperature module 19, thereby extending the service life of the heat insulation plate 11.

[0036] Both the upper module 18 and the lower module 19 have mold cavities 13 on opposite sides, and the two sets of mold cavities 13 have the same shape.

[0037] Using mold cavities 13 with the same shape ensures that the produced parts have consistent size and shape, reduces production errors, improves product consistency and overall quality. Using mold cavities 13 with the same shape simplifies the production process, reduces the extra work caused by changing or adjusting the mold cavities 13, lowers production costs, and facilitates mold maintenance and upkeep, because the same mold cavities 13 can be cleaned, inspected and replaced in a uniform manner, improving work efficiency.

[0038] Both the upper module 18 and the lower module 19 are made of CP2M mold steel.

[0039] By using CP2M die steel, which has a thermal conductivity of 40 W / m°K, the thermal conductivity of CP2M die steel used in manufacturing the upper and lower dies is about 43% higher than that of traditional H13 hot work die steel. The upper and lower heat insulation pads are selectively made of AMANDA glass fiber resin material. At a temperature of 500°C, its thermal conductivity is 0.3 W / m°K, which is only 1.07% of that of H13 steel, meaning that the heat insulation capacity is improved by nearly 100 times. Its compressive strength at high temperatures is 250-300 MPa, which meets the forging impact load strength requirements of screw presses.

[0040] The inner cavity of the upper module 18 is equipped with two sets of upper mold temperature sensors and circuit channels 15. One set of upper mold temperature sensors and circuit channels 15 is close to the mold cavity 13, and the other set of upper mold temperature sensors and circuit channels 15 is close to the outer surface of the upper module 18.

[0041] Two thermocouple temperature sensors are installed in each of the upper and lower molds. One sensor is placed as close as possible to the mold cavity 13 to detect the temperature of the cavity 13, while the other sensor is placed close to the outer surface of the upper and lower molds, near the induction heating coils 14 and 12 of the upper and lower molds, to monitor the outer wall temperature of the molds. When the temperature difference between S1 and S2 increases, the controller increases the induction heating power to narrow the difference. When the temperatures of S1 and S2 are close, the power of the induction coils is reduced to maintain a constant mold temperature. Since the upper mold moves up and down, its surface cools down faster. Therefore, the temperature control and adjustment of the upper mold are required to be faster than that of the lower mold. The temperature control settings for the upper and lower molds differ mainly in the control parameters set by the PLC, specifically in the PID control parameters.

[0042] The inner cavity of the lower module 19 is equipped with two sets of lower mold temperature sensors and circuit channels 20. One set of lower mold temperature sensors and circuit channels 20 is close to the mold cavity 13, and the other set of lower mold temperature sensors and circuit channels 20 is close to the outer surface of the lower module 19.

[0043] The mold uses a medium-frequency induction heating power supply with a fully digital integrated control system. Two temperature measuring points are set on the upper module 18 and the lower module 19 respectively. The heating temperature and heating rate are controlled by feedback based on the data measured by the measuring points.

[0044] Both the upper mold heat insulation pad 17 and the heat insulation plate 11 are made of fiber ceramic pressure-resistant high-temperature heat insulation material.

[0045] By using a pressure-resistant, high-temperature insulating material pad between the module and the mold base, heat conduction between mold structures is blocked, accelerating the temperature balance of the mold cavity and avoiding forming defects caused by uneven forming temperature of the blank. In addition to a limited portion of the energy of induction heating being absorbed by the continuously decreasing blank through mold conduction to raise or maintain the necessary forging temperature, the remaining heat energy is dissipated by the cooling water of the induction coil, radiation from the outer surface of the mold, and convection with the ambient air. A portion of the heat energy is also dissipated through conduction between the upper and lower mold bases, via the press's worktable and slide. This improved efficiency helps reduce costs and ensures production stability and equipment lifespan.

[0046] Working principle: This utility model adds the use of high thermal conductivity mold steel to manufacture the mold cavity, improving heat conduction between the lower mold induction heating coil 12 and the upper mold induction heating coil 14 and the upper module 18 and lower module 19. Heat insulation coating and wrapping are applied to the outer layers of the upper module 18 and lower module 19 to reduce heat dissipation from their outer surfaces. Pressure-resistant high-temperature heat-insulating material pads are used between the upper module 18 and lower module 19 and the lower mold base 10 and upper mold base 16 with cooling channels to block heat conduction between mold structures, accelerating temperature balance in the mold cavity 13 when the upper module 18 and lower module 19 are closed, and avoiding forming defects caused by uneven forming temperature in the formed blank. The upper mold heat insulation pad 17 and heat insulation plate 11 are located on the outer layers of the upper module 18 and lower module 19, respectively, facilitating maintenance and replacement, and possessing strong versatility.

[0047] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A heating and heat preservation device for an aluminum alloy isothermal forging die, characterized in that, include: The lower module (19) and the upper module (18) set on top of the lower module (19); The top of the upper module (18) is provided with an upper mold heat insulation pad (17) for heat insulation of the upper module (18), and the bottom of the lower module (19) is provided with a heat insulation plate (11) for heat insulation of the lower module (19). The upper module (18) is surrounded by an upper mold induction heating coil (14) for heating the upper module (18), and the lower module (19) is surrounded by a lower mold induction heating coil (12) for heating the lower module (19).

2. The heating and heat preservation device for an aluminum alloy isothermal forging die according to claim 1, characterized in that: The upper mold heat insulation pad (17) is provided with an upper mold base (16) with cooling water channels on its top, and the upper mold heat insulation pad (17) is located between the upper mold base (16) with cooling water channels and the upper module (18).

3. The heating and heat preservation device for an aluminum alloy isothermal forging die according to claim 1, characterized in that: The bottom of the heat insulation plate (11) is provided with a lower mold base (10) with cooling water channels, and the heat insulation plate (11) is located between the lower mold base (10) with cooling water channels and the lower module (19).

4. The heating and heat preservation device for an aluminum alloy isothermal forging die according to claim 1, characterized in that: The upper module (18) and the lower module (19) each have a mold cavity (13) on their opposite sides, and the two sets of mold cavities (13) have the same shape.

5. The heating and heat preservation device for an aluminum alloy isothermal forging die according to claim 1, characterized in that: Both the upper module (18) and the lower module (19) are made of CP2M mold steel.

6. The heating and heat preservation device for an aluminum alloy isothermal forging die according to claim 4, characterized in that: The inner cavity of the upper module (18) is equipped with two sets of upper mold temperature sensors and circuit channels (15), one set of upper mold temperature sensors and circuit channels (15) is close to the mold cavity (13), and the other set of upper mold temperature sensors and circuit channels (15) is close to the outer surface of the upper module (18).

7. The heating and heat preservation device for an aluminum alloy isothermal forging die according to claim 4, characterized in that: The inner cavity of the lower module (19) is equipped with two sets of lower mold temperature sensors and circuit channels (20). One set of the lower mold temperature sensors and circuit channels (20) is close to the mold cavity (13), and the other set of the lower mold temperature sensors and circuit channels (20) is close to the outer surface of the lower module (19).

8. The heating and heat preservation device for an aluminum alloy isothermal forging die according to claim 1, characterized in that: The upper mold heat insulation pad (17) and the heat insulation plate (11) are both made of pressure-resistant high-temperature heat insulation material.

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