火电厂锅炉受热面管弯头在役涡流检测装置研究

针对电厂锅炉受热面管在役检测中所具有的两端封闭、管屏间安装紧密以及检测空间狭小等特点,设计了一种可用于奥氏体不锈钢小径管弯头的外放置式马鞍形涡流检测探头装置,按照涡流检测技术标准要求,采用火电厂备用管材加工制作了对比试样管,通过试样检测和现场应用,结果表明：所研制的马鞍形涡流检测探头装置对0.2 mm深以上线性缺陷和D1.4 mm以上孔状缺陷具有较高的检测灵敏度和可靠度,能针对火电厂锅炉受热面管氧化腐蚀较严重,且应力较集中的奥氏体不锈钢弯头部位,实现其在役无损检测。

Study on Online Eddy Current Detecting of the Boiler Heating Surface Tube Elbow in Thermal Power Plants

According to the characteristics of the closed ends, the tight tube panel layouts and the narrow detecting space in online eddy current detecting of the boiler heating surface tube elbow in thermal power plants, an external placed saddle-shaped eddy current detecting probe is designed, which can be used to test the small diameter austenitic stainless steel tube elbow. The comparative sample tube is made in accordance with the eddy current detecting technical standards. Through the sample testing and the applications in thermal power plants, the results show that the designed saddle-shaped eddy current detecting device has better sensitivity and reliability to the linear defects more than 0.2 mm deep and the hole-like defects larger than D1.4 mm. It can realize the non-destructive online testing of the austenitic stainless steel tube elbow that has serious oxidation and corrosion as well as more concentrated stress.