﻿ 绝缘横梁压制成型过程温度场模拟与分析

# 绝缘横梁压制成型过程温度场模拟与分析Simulation and Analysis of Temperature Field in the Compression Forming of Insulating Crossbeam

Abstract: Press forming is the main processing method of power insulation components, which has a certain market prospect. In this paper, the pressing and forming technology of the insulating crossbeam component in the vacuum contactor is studied. ANSYS finite element analysis software is used to simulate the heating process of the insulating crossbeam mold in the pressing process, and the numerical calculation software is used to solve the insulation process of the insulating crossbeam. Based on the detailed analysis of the solution results, the process parameters in the forming process are optimized. Two methods of heating improvement are given: one is to enhance the heating in the low temperature area, and to shorten the heating time. The second is to optimize the temperature setting value of the electric heating pipe in the process of heat preservation, so as to solve the product quality defects encountered in the actual production process. Experiments show that the optimization parameters can effectively improve the quality of products and shorten the production cycle.

1. 引言

2. 绝缘横梁的压制成型工艺

Figure 1. Physical drawing of insulated crossbeam products

BMC团状模材料在压制成型的过程中发生复杂的交联固化反应，由于发生化学反应材料本身会释放一定的热量 [6] 。通过分析绝缘横梁的制品缺陷，可以知道影响绝缘横梁压制成型质量的主要工艺参数为在压制成型过程中加热温度和保温时间。

3. 绝缘横梁压制成型的加热过程温度场模拟

3.1. 绝缘横梁模具加热过程的热传递方式

${q}^{\ast }=-{K}_{nn}\frac{dT}{dn}$ (1)

${q}^{\ast }=a\left({T}_{S}-{T}_{B}\right)$ (2)

3.2. 绝缘横梁模具网格划分

3.3. 绝缘横梁模具加热荷载的加载

Figure 2. Mold model of insulating crossbeam pressing

Figure 3. Diagram of model gridding

(a) 动模电热管分布区域 (b) 定模电热管分布区域

Figure 4. Distribution diagram of electric heating pipe in mold

3.4. 加热过程温度场的求解与分析

(a) Time = 15 min (b) Time = 20 min (c) Time = 30 min

Figure 5. Temperature field distribution in cavity with different heating time

Figure 6. Maximum temperature of each area when time = 30 min

Figure 7. Distribution diagram of electric heating pipe after optimization

(a) Time = 20 min(b) Time = 25 min

Figure 8. Temperature field distribution of cavity surface at different times

4. 绝缘横梁压制成型的保温过程温度场模拟

4.1. 绝缘横梁模具保温载荷的加载

4.2. 保温过程温度场的求解与分析

4.2.1. 保温过程电热管温度设定值为145℃

Figure 9. Variation curve of temperature with time in pressing process

4.2.2. 保温过程电热管温度设定值为150℃

(a) Time = 43 min(b) Time = 50 min

Figure 10. Temperature field distribution in cavity with different holding time

Figure 11. Variation curve of temperature with time in pressing process

4.2.3. 保温过程电热管温度设定值为160℃

(a) Time = 38 min(b) Time = 50 min

Figure 12. Temperature field distribution in cavity with different holding time

Figure 13. Variation curve of temperature with time in pressing process

5. 实验验证

(1) 在模具侧抽芯中增加两根电热管并相应地缩短加热时间，根据仿真结果，加热时间为23~25分钟即可达到工艺要求。

(a) Time = 38 min(b) Time = 43 min

Figure 14. Temperature field distribution in cavity with different holding time

(2) 根据仿真结果，设定保温过程加热管的保温温度设定值为150℃ ± 3℃，对BMC团状模材料进行预热，预热温度为50℃~60℃，保温时长为775~785秒即可使绝缘横梁固化度达到0.99以上。

Table 1. Process parameter setting and actual results of electric heating pipe with moving mold

Table 2. Process parameter setting and actual results of electric heating pipe with fixed mold

Figure 15. Actual production layout of electric heating pipe

6. 小结

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