Digital temperature control system for large-size thin-wall aluminum alloy casting low-pressure die

Abstract

The invention discloses a digital temperature control system for a large-size thin-wall aluminum alloy casting low-pressure die. The digital temperature control system comprises a temperature monitor, a heating device, a cooling device and a control device. A cavity sprue is used as a sphere center, a plurality of spherical surfaces are determined from the sphere center to the outside, the area between the sphere center and the sphere surface closest to the sphere center and the area between every two adjacent spherical surfaces are monitoring areas, and the temperature monitors are arranged in the monitoring areas; the heating device is used for heating each monitoring area, and the cooling device is used for cooling each monitoring area; and the control device controls the heating device to heat or controls the cooling device to cool according to the mold temperature detected by the temperature monitor, so that the temperatures of the at least two monitoring areas are different. When the temperature control system is used for producing large-size thin-wall aluminum alloy castings, the heating device and the cooling device can be automatically controlled to adjust the temperature of the mold, so that the temperature of the mold is normal process temperature, and the quality of the castings is effectively ensured.

Description

Technical Field

[0001] The invention belongs to the technical field of mold temperature control, and in particular relates to a digital temperature control system for a low-pressure mold of a large-size thin-walled aluminum alloy casting. Background Art

[0002] Large-size thin-walled aluminum alloy refers to aluminum alloy castings with a single-side length of more than 1000mm and a wall thickness of 2 to 8mm. Due to its complex structure, thin wall, and large size, it faces many problems in the casting process. In order to ensure the finished product rate of castings, the temperature of the aluminum alloy liquid used needs to be controlled within a certain range to ensure that the aluminum alloy liquid has high fluidity and can be smoothly filled into the mold cavity, thereby reducing defects such as poor gates, pores, and shrinkage.

[0003] In addition to the temperature of the aluminum alloy liquid itself, the temperature of the mold used during the casting process is also an important factor affecting the quality of the casting. If the mold temperature is too low, the casting will be over-solidified, resulting in shrinkage holes, looseness and other problems in the casting, while if the mold temperature is too high, it will easily cause defects such as cracks and pores on the surface of the casting. Therefore, how to accurately control the mold temperature to improve the quality of the finished casting is a problem that needs to be solved.

[0004] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention and should not be regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art. Summary of the invention

[0005] The purpose of the present invention is to provide a digital temperature control system for low-pressure molds of large-size thin-walled aluminum alloy castings, which automatically adjusts the mold temperature through the temperature control system to keep the mold temperature at an appropriate process temperature, thereby ensuring product quality.

[0006] In order to achieve the above object, a technical solution provided by a specific embodiment of the present invention is as follows:

[0007] A digital temperature control system for low-pressure molds of large-size thin-walled aluminum alloy castings, comprising a temperature monitor, a heating device, a cooling device and a control device;

[0008] Taking the center of the cavity gate as the spherical center, a number of spherical surfaces are determined from the spherical center outwards, and the area between the spherical center and the closest spherical surface and the area between two adjacent spherical surfaces are all monitoring areas, and the temperature monitor is arranged in each monitoring area;

[0009] The heating device is used to heat each monitoring area respectively, and the cooling device is used to cool each monitoring area respectively;

[0010] The control device controls the heating device to heat or controls the cooling device to cool according to the mold temperature detected by the temperature monitor, so that the temperatures of at least two monitoring areas are different.

[0011] In one or more embodiments of the present invention, several monitoring areas from the center of the sphere to the outside are set as area 1, area 2, area 3, area 4, area 5...area n, and the temperature control system controls the temperature of area 1 to 300-330°C.

[0012] In one or more embodiments of the present invention, the target temperature of the second zone is 330-350°C.

[0013] In one or more embodiments of the present invention, the target temperature of the third zone is 300-330°C.

[0014] In one or more embodiments of the present invention, the target temperature of the fourth zone is 300-350°C.

[0015] In one or more embodiments of the present invention, the target temperature of the fifth zone is 350-380°C.

[0016] In one or more embodiments of the present invention, the radii of several spherical surfaces extending outward from the center of the sphere are set to R1, R2, R3, R4, R5...Rn respectively; the length of R1 is 90-110 mm.

[0017] In one or more embodiments of the present invention, the length of R2 is 160-190 mm.

[0018] In one or more embodiments of the present invention, the length of R3 is 290-310 mm.

[0019] In one or more embodiments of the present invention, the length of R4 is 470-530 mm, and the length of R5 is 580-620 mm.

[0020] Compared with the prior art, for large-sized thin-walled aluminum alloy castings, the present invention divides the mold into different areas, and each area is respectively provided with a temperature monitoring device, a heating device and a cooling device. The temperature of each area is detected in real time by the temperature monitoring device, and the temperature of each area is adjusted by the heating device and the cooling device, so that the mold temperature is adapted to the casting of large-sized thin-walled aluminum alloy castings, thereby ensuring the quality of the castings, and the product qualification rate can reach 98%. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 It is a structural schematic diagram of a mold cavity plate in one embodiment of the present invention;

[0023] Figure 2 It is a schematic diagram of dividing different spherical surfaces on a mold cavity plate in one embodiment of the present invention.

[0024] Description of main reference numerals:

[0025] 1. Cavity plate; 2. Gate. DETAILED DESCRIPTION

[0026] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0027] A specific embodiment of the present invention provides a digital temperature control system for a low-pressure mold for a large-size thin-walled aluminum alloy casting, including a temperature monitor, a heating device, a cooling device and a control device. The center of the mold cavity gate is taken as the center of the sphere, and a plurality of spherical surfaces are determined from the center of the sphere to the outside. The area between the center of the sphere and the spherical surface closest to it, and the area between two adjacent spherical surfaces are all monitoring areas. A temperature monitor is arranged in each monitoring area; the heating device is used to heat each monitoring area separately, and the cooling device is used to cool each monitoring area separately; the control device controls the heating device to heat or controls the cooling device to cool according to the mold temperature detected by the temperature monitor, so that the temperatures of at least two monitoring areas are different.

[0028] Specifically, according to the structure of large-size thin-walled aluminum alloy castings, different monitoring areas are determined with the center of the cavity gate as the center of the ball. By controlling the temperature of the monitoring area within the respective target temperature, each part of the casting can solidify at an appropriate temperature during the casting process, thereby ensuring the overall quality of the casting and improving the casting yield rate. In addition, the temperature of the monitoring area farthest from the center of the ball is greater than or equal to the maximum temperature of the remaining monitoring areas, so that the position of the product far from the gate can solidify at an appropriate temperature, ensuring the quality of the casting.

[0029] Furthermore, several monitoring areas from the center of the sphere to the outside are set as area 1, area 2, area 3, area 4, area 5...area n. Taking the division into 5 monitoring areas as an example, the temperature control system controls the target temperature of area 1 to 300-330°C, the target temperature of area 2 to 330-350°C, the target temperature of area 3 to 300-330°C, the target temperature of area 4 to 300-330°C, and the target temperature of area 5 to 350-380°C.

[0030] Furthermore, the diameters of several spherical surfaces from the center of the sphere to the outside are set to R1, R2, R3, R4, R5...Rn, respectively, the length of R1 is 90-110 mm, the length of R2 is 160-190 mm, the length of R3 is 290-310 mm, the length of R4 is 470-530 mm, and the length of R5 is 580-620 mm.

[0031] Specifically, several monitoring areas can be divided by limiting the diameter of each spherical surface, and by controlling the monitoring areas to be at a target temperature, the casting can be formed at a suitable temperature, thereby ensuring that the casting has excellent performance.

[0032] Furthermore, the control device is a computer, the temperature monitor is an infrared temperature sensor or a thermocouple temperature sensor, the heating device is an electric heating tube, and the cooling device is a cooling water circulation. A water circulation pipeline is set in the corresponding monitoring area in the mold, and a water pump is used to make the cooling water flow through the water circulation pipeline, thereby achieving the cooling purpose.

[0033] Specifically, the temperature monitor detects the temperature of each monitoring area in real time, and the computer collects the temperature value detected by the temperature monitor and compares it with the target temperature of the monitoring area. When the real-time temperature is lower than the target temperature, the computer controls the heating device to heat the monitoring area. When the real-time temperature is higher than the target temperature, the computer controls the cooling device to cool the monitoring area to achieve the cooling purpose.

[0034] Furthermore, each monitoring area is provided with a heating device and a cooling device, the heating device is an electric heating tube, and the cooling device is a cooling water circulation. The temperature of each monitoring area is detected in real time through temperature monitoring and compared with the target temperature. When the monitoring area is not at the target temperature, the heating device is controlled to heat or the cooling device is controlled to cool. Among them, a computer is selected to control the heating device and the cooling device, and the temperature monitor is an infrared temperature sensor or a thermocouple temperature sensor.

[0035] Furthermore, the mold used can be made of different thermal conductive materials according to the monitoring area. The thermal conductive material is beryllium copper or 45 steel. When the mold is made of 45 steel, the mold surface is sprayed with protective coating. The protective coating uses conventional anti-rust coating, such as GN-201 high temperature anti-rust paint and GN-205 wear-resistant anti-rust paint.

[0036] Beryllium copper has excellent thermal conductivity, which helps to control the mold temperature; 45 steel material also has good thermal conductivity, which can improve heat transfer and help regulate the mold temperature. In addition, beryllium copper and 45 steel materials also have good mechanical properties, which can increase the service life of the mold.

[0037] The present invention is further described in detail below in conjunction with specific embodiments.

[0038] Example 1

[0039] The target casting product is a medium-sized shell of an industrial textile machine, with a size of 1500*1500*200mm and a minimum wall thickness of 6mm. The cavity plate constituting the cavity in the casting mold is as follows: Figure 1 As shown, combined Figure 2 , taking the center of the gate as the center of the sphere, determine several spherical surfaces from the center of the sphere to the periphery of the cavity plate. Figure 2 The middle dotted line refers to the circle corresponding to each spherical surface on the plane area of ​​the cavity disk. The area between the center of the sphere and the spherical surface closest to it and the rest between the other two adjacent spherical surfaces are all monitoring areas. In this embodiment, a total of 5 spherical surfaces are determined, and the corresponding 5 monitoring areas are set as the 1st area, the 2nd area, the 3rd area, the 4th area and the 5th area from the center of the sphere to the outside.

[0040] The digital temperature control system for low-pressure molds of large-size thin-walled aluminum alloy castings includes several temperature monitors, heating devices, cooling devices and control devices. The temperature monitor is specifically a thermocouple temperature sensor. Several thermocouple temperature sensors are arranged in each monitoring area corresponding to the cavity disk to monitor the temperature of each monitoring area of ​​the cavity disk in real time. The heating device is specifically an electric heating pipe, and the cooling device is a cooling water circulation pipeline arranged in the mold. Each corresponding monitoring area in the mold is equipped with an electric heating pipe and a cooling water circulation pipeline.

[0041] The control device is a computer. The computer controls the electric heating tube to heat or controls the water pump to adjust the water flow in the cooling water circulation pipeline according to the temperature detected by the thermocouple temperature sensor, so as to adjust the temperature of each monitoring area, so that the temperature of the first area is 300-330°C, the temperature of the second area is 330-350°C, the temperature of the third area is 300-330°C, the temperature of the fourth area is 300-330°C, and the temperature of the fifth area is 350-380°C. Each monitoring area is cast within the above temperature range, and the prepared product is of excellent quality, with a qualified rate of 98%.

[0042] The specific method of controlling mold temperature is as follows:

[0043] like Figure 2 As shown, with the center of the gate as the center of the sphere, several spherical surfaces are determined from the center of the sphere to the periphery of the cavity disk. The area between the center of the sphere and the closest spherical surface and the rest between the other two adjacent spherical surfaces are monitoring areas. In this embodiment, a total of 5 spherical surfaces are determined, and the corresponding 5 monitoring areas are set as the first area, the second area, the third area, the fourth area and the fifth area. The radii of the 5 spherical surfaces are set as R1, R2, R3, R4 and R5, respectively. R1 is 100mm, R2 is 175mm, R3 is 300mm, R4 is 500mm, and R5 is 600mm. The manufacturing material of the cavity disk is divided according to each monitoring area. The first area and the third area are made of 45# steel, and the second area, the fourth area and the fifth area are made of beryllium copper. The use of different thermal conductive materials is conducive to the precise control of the temperature of each monitoring area.

[0044] The target temperature of the first zone is set at 300-330°C, the target temperature of the second zone is set at 330-350°C, the target temperature of the third zone is set at 300-330°C, the target temperature of the fourth zone is set at 300-330°C, the target temperature of the fifth zone is set at 350-380°C, and a thermocouple temperature sensor is installed in each monitoring area.

[0045] Electric heating pipes and cooling water circulation pipes are installed in each monitoring area. A water pump is used to adjust the water flow in the cooling water circulation pipe. At the same time, the electric heating pipes and the water pump are controlled by a computer.

[0046] During casting, the thermocouple temperature sensor is started to detect the temperature of each monitoring area in real time. The computer compares the collected real-time temperature with the target temperature. If the real-time temperature of the monitoring area is lower than the target temperature range, the computer controls the electric heating pipe to heat the monitoring area to increase the temperature. If the real-time temperature of the monitoring area is higher than the target temperature range, the computer controls the water pump to increase the water flow in the cooling water circulation pipe to lower the temperature, so that the temperature of each monitoring area is within the target temperature range.

[0047] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered exemplary and non-restrictive in all respects, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention.

[0048] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A digital temperature control system for low-pressure molds of large-size thin-walled aluminum alloy castings, characterized in that: Includes temperature monitor, heating device, cooling device and control device; Taking the center of the cavity gate as the spherical center, a number of spherical surfaces are determined from the spherical center outwards, and the area between the spherical center and the closest spherical surface and the area between two adjacent spherical surfaces are all monitoring areas, and the temperature monitor is arranged in each monitoring area; The heating device is used to heat each monitoring area respectively, and the cooling device is used to cool each monitoring area respectively; The control device controls the heating device to heat or controls the cooling device to cool according to the mold temperature detected by the temperature monitor, so that the temperatures of at least two monitoring areas are different.

2. The digital temperature control system for low-pressure molds of large-size thin-walled aluminum alloy castings according to claim 1 is characterized in that: Several monitoring areas from the center of the sphere outward are set as the first area, the second area, the third area, the fourth area, the fifth area...the nth area in sequence, and the temperature control system controls the temperature of the first area to 300-330°C.

3. The digital temperature control system for low-pressure molds of large-size thin-walled aluminum alloy castings according to claim 2 is characterized in that: The target temperature of the second zone is 330-350°C.

4. The digital temperature control system for low-pressure molds of large-size thin-walled aluminum alloy castings according to claim 2 is characterized in that: The target temperature of the third zone is 300-330°C.

5. The digital temperature control system for low-pressure molds of large-size thin-walled aluminum alloy castings according to claim 2 is characterized in that: The target temperature of the fourth zone is 300-350°C.

6. The digital temperature control system for low-pressure molds of large-size thin-walled aluminum alloy castings according to claim 2 is characterized in that: The target temperature of the 5th zone is 350-380°C.

7. The digital temperature control system for low-pressure molds of large-size thin-walled aluminum alloy castings according to claim 1 is characterized in that: The radii of several spherical surfaces extending outward from the center of the sphere are set to be R1, R2, R3, R4, R5...Rn respectively; the length of R1 is 90-110 mm.

8. The digital temperature control system for low-pressure molds of large-size thin-walled aluminum alloy castings according to claim 7 is characterized in that: The length of R2 is 160-190 mm.

9. The digital temperature control system for low-pressure molds of large-size thin-walled aluminum alloy castings according to claim 7 is characterized in that: The length of R3 is 290-310 mm.

10. The digital temperature control system for low-pressure molds of large-size thin-walled aluminum alloy castings according to claim 7, characterized in that: The length of R4 is 470-530 mm, and the length of R5 is 580-620 mm.

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