US-20260124678-A1 - METHOD FOR EVALUATING STABILITY OF COOLING EFFECT OF COOLING SYSTEM FOR LOW-PRESSURE CASTING OF ALUMINUM ALLOY WHEEL HUB

Abstract

Provided is a method for evaluating the stability of the cooling effect of a cooling system for low-pressure casting of an aluminum alloy wheel hub, relating to the technical field of low-pressure casting of automobile wheel hubs. The method includes: selecting a mold object; arranging a thermocouple, and acquiring temperature data; changing an initial temperature at a temperature measuring point of the thermocouple, and further acquiring real-time temperature data; extracting characteristic temperature data, and performing linear regression between an initial temperature value and a characteristic temperature value; and performing temperature data fluctuation analysis, and quantitatively measuring the stability of the cooling effect of the cooling system by using a maximum value and a minimum value of deviation of discrete points from a fitting curve as indexes.

Inventors

• Yiming Li
• Hongcan LIU
• Ji Wang
• Shiwei Guo
• Jianing QI
• Yong Li
• Xuewen Qian
• Yajun YIN
• Tianxiao Yuan
• Xu Shen
• Jianxin Zhou
• Xiaoyuan JI
• Hongfeng Cui
• Lin Zhu

Assignees

• CITIC DICASTAL CO., LTD.

Dates

Publication Date

20260507

Application Date

20250827

Priority Date

20241106

Claims (9)

1. 1 . A method for evaluating the stability of the cooling effect of a cooling system for low-pressure casting of an aluminum alloy wheel hub, comprising: performing Step S 1 : selecting a mold object that can be used for evaluating the stability of the cooling effect of the cooling system; performing Step S 2 : arranging a thermocouple, and acquiring temperature data; performing Step S 3 : changing an initial temperature at a temperature measuring point of the thermocouple, and further acquiring real-time temperature data; performing Step S 4 : extracting characteristic temperature data, and performing linear regression between an initial temperature value and a characteristic temperature value; and performing Step S 5 : performing temperature data fluctuation analysis, and quantitatively measuring the stability of the cooling effect of the cooling system by using a maximum value and a minimum value of deviation of discrete points from a fitting curve.
2. 2 . The method for evaluating the stability of the cooling effect of a cooling system for low-pressure casting of an aluminum alloy wheel hub according to claim 1 , wherein in the step S 1 , a mold corresponding to an aluminum alloy wheel hub casting that is stably produced is selected as the mold object for evaluating the stability of the cooling effect of the cooling system.
3. 3 . The method for evaluating the stability of the cooling effect of a cooling system for low-pressure casting of an aluminum alloy wheel hub according to claim 2 , wherein cooling process parameters are maintained unchanged during a stability evaluation test of the cooling effect of the cooling system.
4. 4 . The method for evaluating the stability of the cooling effect of a cooling system for low-pressure casting of an aluminum alloy wheel hub according to claim 3 , wherein the opening time and the closing time of each cooling pipeline, and a flow rate of a cooling medium in each cooling pipeline are set to be kept unchanged during a production cycle of the aluminum alloy wheel hub.
5. 5 . The method for evaluating the stability of the cooling effect of a cooling system for low-pressure casting of an aluminum alloy wheel hub according to claim 1 , wherein in the step S 3 , the initial temperature at the temperature measuring point of the thermocouple is changed by closing one of cooling pipelines and acquiring temperature data at a preset cycle.
6. 6 . The method for evaluating the stability of the cooling effect of a cooling system for low-pressure casting of an aluminum alloy wheel hub according to claim 5 , wherein the number of continuous production cycles during which each single cooling pipeline is closed and the number of continuous production cycles during which each single cooling pipeline is reopened are not particularly limited.
7. 7 . The method for evaluating the stability of the cooling effect of a cooling system for low-pressure casting of an aluminum alloy wheel hub according to claim 6 , wherein the number of continuous production cycles during which each single cooling pipeline is closed is equal, and the number of continuous production cycles during which each single cooling pipeline is reopened is equal.
8. 8 . The method for evaluating the stability of the cooling effect of a cooling system for low-pressure casting of an aluminum alloy wheel hub according to claim 1 , wherein in the step S 4 , characteristic temperature values on a temperature curve before mold opening are selected for analysis.
9. 9 . The method for evaluating the stability of the cooling effect of a cooling system for low-pressure casting of an aluminum alloy wheel hub according to claim 1 , wherein in the step S 5 , the smaller a span between a maximum value and a minimum value of deviation of discrete points from a linear regression curve, the more stable the cooling system.

Description

FIELD OF THE INVENTION The present disclosure relates to the technical field of low-pressure casting of automobile wheel hubs, in particular to a method for evaluating the stability of the cooling effect of a cooling system for low-pressure casting of an aluminum alloy wheel hub. BACKGROUND OF THE INVENTION An integrally cast aluminum alloy wheel hub integrates a hub, a spoke, and a rim, has high strength, high dimensional accuracy, easy assembly, and beautiful appearance, and is widely used in high-end motorcycles and cars. Low-pressure casting is widely used in the production process of aluminum alloy wheel hub castings due to the advantages of smooth filling, high crystallization pressure (0.1-0.15 MPa), and easy complete automation. In order to further improve the production efficiency and improve the mechanical properties of aluminum alloy wheel hubs, it is often necessary to cool a metal mold used in low-pressure casting. Common cooling methods include various cooling forms such as full air cooling, local water cooling, full water cooling and water mist mixing, and different manufacturers have been exploring cooling forms and cooling processes suitable for their own plants. The stable control of the temperature of a mold in the production process is critical to the stability of the aluminum alloy wheel hub castings because the shrinkage cavity and shrinkage porosity, misrun and coarse grains of castings significantly affect the mechanical properties of wheel hub castings, and this series of defects is greatly influenced by a temperature field. In the low-pressure casting mass production of the aluminum alloy wheel hub castings, the same temperature acquisition point exhibits different temperature curves at different cycles even with the same cooling process setting due to various factors such as fluctuations in a flow rate of a cooling medium and inconsistent production cycle durations. Meanwhile, since the metal mold used in low-pressure casting of aluminum alloy wheel hubs tends to have a large number of temperature acquisition points, these temperature acquisition points influence each other. On the other hand, when the mold contains a cooling system, the stability of the cooling effect of the cooling system is critical to the control of the mold temperature and the stability of the quality of the aluminum alloy wheel hub. However, the production cycle of each aluminum alloy wheel hub casting has differences in a series of conditions such as the initial mold temperature, the flow rate of the cooling medium, a temperature curve, and a cycle duration, resulting in difficulty in satisfying the harsh conditions required by a single-factor control variable method in the process of measuring the stability of the cooling effect of the cooling system. Therefore, how to evaluate the stability of the cooling system is an important problem to further improve the quality stability of castings. Therefore, in view of the problems existing in the prior art, by virtue of the active research and improvement of designers of the present disclosure based on years of experience in the industry, the present disclosure provides a method for evaluating the stability of the cooling effect of a cooling system for low-pressure casting of an aluminum alloy wheel hub. SUMMARY OF THE INVENTION An object of the present disclosure is to provide a method for evaluating the stability of the cooling effect of a cooling system for low-pressure casting of an aluminum alloy wheel hub in view of the defects in the prior art that the production cycle of each aluminum alloy wheel hub casting has differences in a series of conditions such as the initial mold temperature, a flow rate of a cooling medium, a temperature curve, and a cycle duration, resulting in difficulty in satisfying the harsh conditions required by a single-factor control variable method in the process of measuring the stability of the cooling effect of the cooling system. To achieve the object of the present disclosure, the present disclosure provides a method for evaluating the stability of the cooling effect of a cooling system for low-pressure casting of an aluminum alloy wheel hub, including: performing Step S1: selecting a mold object that can be used for evaluating the stability of the cooling effect of the cooling system;performing Step S2: arranging a thermocouple, and acquiring temperature data;performing Step S3: changing an initial temperature at a temperature measuring point of the thermocouple, and further acquiring real-time temperature data;performing Step S4: extracting characteristic temperature data, and performing linear regression between an initial temperature value and a characteristic temperature value; andperforming Step S5: performing temperature data fluctuation analysis, and quantitatively measuring the stability of the cooling effect of the cooling system by using a maximum value and a minimum value of deviation of discrete points from a fittin