ABSTRACT

The aim of the research presented in this work was to verify the occurrence of the thermoelastic effect in compacted steel wire ropes for future research applications and TSA methods. It was examined using a Testo 890 thermal camera during tests consisting of 10 cycles of loading of rope samples to levels under the yield stress, performed on a tensile strength machine. Average measured changes of temperature caused by a 1000 MPa change of stress were 0.8 K during loading and 1.0 K during unloading. It was found that rapid unloading caused temperature changes that were closer to the theoretical values calculated for an isotropic body and adiabatic conditions. Probable reasons for those differences were investigated. Furthermore, temperatures of samples recorded after each cycle of loading were analysed. Heating of samples during cycles of elastic elongation was observed, pointing to exothermal processes taking place in the internal structure of the ropes. Application of IR cameras to detect dynamic load changes using the thermoelastic effect in steel wire ropes was proposed and evaluated. Usage of described novelty method in inspection of steel wire ropes during the operation was discussed.

摘要

这项工作中提出的研究的目的是验证压实钢丝绳中热弹性效应的发生，以用于未来的研究应用和 TSA 方法。在测试期间使用 Testo 890 热像仪对其进行了检查，该测试包括在拉伸强度机器上进行的 10 个绳索样品循环加载到屈服应力下的水平。由 1000 MPa 应力变化引起的平均温度测量变化在加载期间为 0.8 K，在卸载期间为 1.0 K。发现快速卸载引起的温度变化更接近于为各向同性体和绝热条件计算的理论值。调查了这些差异的可能原因。此外，分析了每个加载循环后记录的样品温度。观察到在弹性伸长循环期间样品的加热，表明绳索的内部结构中发生了放热过程。提出并评估了红外摄像机在利用钢丝绳中的热弹性效应检测动态载荷变化方面的应用。讨论了所描述的新方法在运行过程中钢丝绳检测中的应用。