在触角循环负荷下预测复杂设备螺栓结构的预加载放松
Xiaohan Lu1, Min Zhu1, Chao Li1
1College of Nuclear Science and Technology, Naval University of Engineering, Wuhan 430033, China.
Sensors (Basel, Switzerland)
|June 19, 2024
概括
在混合负载下松动螺栓减少了预装载,影响了结构安全. 这项研究分析了影响螺栓松动的因素,并提出了用于提高关键应用中的监控和可靠性的预测模型.
科学领域:
- 机械工程 机械工程
- 材料科学 材料科学 材料科学
- 结构完整性 结构完整性
背景情况:
- 螺栓是航空航天和高速铁路中的关键紧固件,但在混合负载下松动会损害结构安全.
- 目前的监测技术不足以实时检测螺栓预装载量下降,造成重大风险.
- 了解螺栓预装载放松对于确保设备安全和可靠性至关重要.
研究的目的:
- 在各种条件下实验研究8.8级六角螺栓在装载前放松规律.
- 校准扭矩系数并分析表面粗度,负载波形和周期性位移对放松的影响.
- 开发和评估螺栓预加载松动的预测模型.
主要方法:
- 在受控条件下对8.8级六角螺栓进行实验分析.
- 检查参数,包括加载波形,表面粗度,移位频率,螺栓强度,接触面积和初始预加载.
- 放松定律的建模使用全米和九级多项式函数,通过最小平方法确定参数.
主要成果:
- 光滑的表面,高频条件,半正弦波负载和高强度螺栓具有卓越的抗松动性能.
- 螺栓预加载放松发生在两个阶段:快速下降,随后缓慢下降,边界约为5-10个周期.
- 九级多项式函数实现了超过90.4%的预测准确度,超过了全量模型 (71.7%至85.5%).
结论:
- 预测模型,特别是九级多项式函数,可以准确地预测螺栓预加载松动.
- 这些发现为加强螺栓松动监控和延长关键设备使用寿命提供了理论支持.
- 优化的螺栓设计和操作条件可以显著提高抗松动性能和结构安全性.
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