Optimization and Tensile Properties of Composite Insulator at High and Low Temperature
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摘要: 为了探究复合绝缘子的承载力受高低温以及芯棒与端部金具压接工艺的影响规律,得出最后优化的压接方式,对绝缘子芯棒和端部金具的高低温拉伸试验结果进行了有限元模拟分析. 在常温状态对金具与芯棒的受力进行了模拟,结果与实验数据吻合较好;设计出10种压接工况,评估最优的复合绝缘子端部金具的预紧应力工况;进一步对高低温下的绝缘子承载能力进行了仿真. 研究结果表明:当预紧应力沿金具径向均匀分布并预留金具长度的18%~25%无预紧力的工况下,复合绝缘子链接的承载能力最优,最优模型的弹性极限荷载较现有厂家工艺增大8.23%;本文模拟方法能较好地模拟高低温状态下的绝缘子力学性能,但压接优化对其承载能力提升不明显.Abstract: In order to find out the influence of high and low temperature and the crimping process between the core rod and the end fittings on the bearing capacity of composite insulator, and to get the final optimized crimping mode, the finite element simulation analysis was carried out on the high and low temperature tensile test results of the core rod and the end fittings.Firstly, the stress of the fittings and mandrels was simulated at normal temperature, and the results were in good agreement with the experimental data. Then, 10 kinds of crimping conditions were designed to evaluate the optimal preloading conditions of the end fittings of composite insulator. The results show that when the preloading stress is evenly distributed along the radial direction of the fittings and 18% − 25% of the length of the fittings is reserved, the bearing capacity of the composite insulator link is the best, and the elastic limit load of the optimal model is 8.23% higher than that of the existing manufacturers. The simulation method can also be used to simulate the mechanical properties of insulators at high and low temperature, but the compression optimization cannot improve the bearing capacity significantly.
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Key words:
- composite insulators /
- fitting /
- preload /
- tensile properties /
- optimization
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表 1 Q235碳素结构钢金具力学性能
Table 1. Mechanical properties of Q235 carbon steel fittings
屈服强
度/MPa极限强
度/MPa泊松比 弹性模
量/GPa热膨胀系数/K−1 235 400 0.28 210 12.2 × 10−6 表 2 单向玻璃纤维增强环氧树脂力学性能
Table 2. Mechanical properties of unidirectional glass fiber reinforced epoxy resin
屈服强
度/MPa泊松比 径向弹性模量/GPa 轴向弹性模量/GPa 热膨胀系数/K−1 452 0.294 13 72 3.29 × 10−6 -
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