Abstract

The work is devoted to a comparative study of magnetoresistive and Hall magnetic field sensors used as primary transducers in multichannel magnetic flaw-detection systems. The principle of operation and application features of anisotropic magnetoresistive (AMR) field sensors are considered. Comparative tests of AMR and Hall sensors were carried out. The main objective of these studies was to select optimum measuring transducers necessary to achieve the required metrological and operational characteristics. We have developed and investigated a multichannel magnetoresistive system for measuring fields due to defects and processing the results of nondestructive testing using a magnetic (MFL—magnetic flux leakage) method. Based on this method, a new small-sized flaw-detection facility has been created and introduced in the industry for automated continuous in-process magnetic inspection and identification of defects in electric-welded small- and medium-diameter pipes over the entire wall thickness, i.e., over the entire product volume. It is shown that the use of computer technologies and high-resolution thin-film matrix transducers made using advanced technology for manufacturing AMR sensors significantly increases the capabilities of the flaw detector and makes it possible to detect not only defects such as violations of metal continuity and edge displacements, but also defects caused by violation of welding conditions such as cracks, fistulas, arc freezings, and sticking edges in the weld area. The system based on new-generation single-chip thin-film matrix transducers is highly sensitive and allows detecting both surface and bulk defects in a noncontact manner with a large gap and at a high speed.

中文翻译：

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应用各向异性磁阻场传感器测试中，小直径管道全部体积的特点和优势

摘要

这项工作致力于对用作多通道磁探伤系统中的主要传感器的磁阻和霍尔磁场传感器进行比较研究。考虑了各向异性磁阻（AMR）场传感器的工作原理和应用特点。进行了AMR和霍尔传感器的对比测试。这些研究的主要目的是选择实现所需的计量和操作特性所需的最佳测量传感器。我们已经开发并研究了一种多通道磁阻系统，用于测量由于缺陷引起的磁场并使用磁（MFL-磁通量泄漏）方法处理无损检测的结果。基于这种方法，建立了一个新的小型探伤设施，并将其引入行业，用于在生产过程中自动连续进行磁检测，并在整个壁厚（即整个壁厚）上识别电焊中小直径管道中的缺陷。整个产品量。结果表明，使用计算机技术和使用先进技术制造的高分辨率薄膜矩阵换能器制造AMR传感器，显着提高了探伤仪的能力，并且不仅能够检测诸如破坏金属连续性和边缘位移，还有由于违反焊接条件而导致的缺陷，例如裂纹，瘘管，电弧冻结以及焊接区域中的粘附边缘。