Juraszek Janusz
Faculty of Materials, Civil and Environmental Engineering, University of Bielsko-Biala; 43-309 Bielsko-Biala, Poland.
Materials (Basel). 2019 Feb 14;12(4):564. doi: 10.3390/ma12040564.
Non-destructive tests of gantry cranes by means of the residual magnetic field (RMF) method were carried out for a duration of 7 years. Distributions of the residual magnetic field tangential and the normal components of their gradients were determined. A database of magnetograms was created. The results show that the gradients of tangential components can be used to identify and localize stress concentration zones in gantry crane beams. Special attention was given to the unsymmetrical distribution of the tangential component gradient on the surface of the crane beam No. 5 (which was the most loaded one). The anomaly was the effect of a slight torsional deflection of the beam as it was loaded. Numerical simulations with the finite element method (FEM) were used to explain this phenomenon. The displacement boundary conditions introduced into the simulations were established experimentally. Validation was carried out using the X-ray diffraction method, which confirmed the location of strain concentration zones (SCZs) identified by means of RMF testing.
采用剩磁场（RMF）法对龙门起重机进行了7年的无损检测。测定了剩磁场切向分量及其梯度的法向分量的分布。创建了磁图数据库。结果表明，切向分量的梯度可用于识别和定位龙门起重机梁中的应力集中区域。特别关注了5号起重机梁（负荷最大的梁）表面切向分量梯度的不对称分布。该异常是梁在加载时轻微扭转挠度的影响。使用有限元法（FEM）进行数值模拟来解释这一现象。模拟中引入的位移边界条件是通过实验确定的。使用X射线衍射法进行了验证，该方法证实了通过RMF测试识别出的应变集中区域（SCZ）的位置。
