随着超临界、超超临界燃煤机组的大量应用, 发电设备上“家族性”缺陷随之产生, 堆焊层与基体脱壳缺陷导致司太立合金(Stellite)脱落就是一例。司太立合金是一种耐磨、耐腐蚀及耐高温氧化的硬质合金。介绍了对超临界、超超临界燃煤机组主汽门、调门堆焊层, 采用超声波检测的工作原理、工艺方法、检测仪要求和检测资质。通过案例分析, 解读了司太立合金堆焊层与基体“脱壳”的主要原因及评判结果, 为进一步了解和跟踪司太立合金堆焊层表面裂纹和“脱壳”缺陷, 提供防范措施和技术支撑。

With the wide application of supercritical, ultra supercritical coal-fired units, power generation equipment “familial” defects resulting, overlaying welding layer and matrix shelling defect causes the Stellite shedding is an example. The stellite are hard alloy abrasion resistant, resistant to corrosion and high temperature oxidation. The supercritical, ultra supercritical coal-fired unit main steam valve, valve surfacing layer, working principle, using ultrasonic testing technique, testing instrument and testing qualification requirements. Through the case analysis, the main reason of stellite welding layer and matrix “shelling” and the evaluation results, to further understand and track the stellite surfacing layer and crack “shelling” defect, provide preventive measures and technical support.