热轧圆钢直径的在线检测中温度场影响的实验研究

An Experimental Investigation About the Influence of Temperature Field on Hot Bar Diameter On-Line Measurement

本文对在热轧圆钢直径的光学非接触检测方法中、因圆钢周围温度场导致光线偏折而产生的测量误差进行了分析。提出了减小该项误差的方法。用干涉法测量了高温圆钢周围的温度场,给出在自然对流状态下中等尺寸圆钢周围温度场的分布规律;并用数值计算方法得出了光线在该温度场中传播的轨迹;建立了沿不同方向测量圆钢直径时、光线偏折误差的修正函数。最后,对光线偏折的数值计算结果(角偏移)用干涉法进行了精度对比。初步进行了热轧圆钢直径测量的误差修正实验,得出了若干结论。

In the optical measurement of diameter of hot-rolling bar, ligh deflection is produced as a result of the temperature field around the bar. In this article, the authors have analyzed the error caused by the light deflection and presented a new method to reduce it. The temperature field around a hot bar has been measured by using interferometry aad the temperature field distribution patterns for a series of medium-size hot bars are given in the case of natural convection. Furthermore, the traces of the light rays propagating in the temperature field are got by using numerical computing methods. The correction-functions for the light deflection error of bar diameter measurement in several different directions are obtained. Finally, the numerical values of the light deflection (angular deflection) are compared with those obtained by an interferometric system. The error correction experiment for the hot bar diameter measurement has been performed, and several conclusions are obtained.