Mitsubishi Heavy Industries Technical Review
    Vol. 56 No. 1 (2019)   New Products & Technologies
    Technical Papers

    Development of Thickness Trend Monitoring Technology (Thin-Film UT Sensor) and Field Verification of Water Treatment Technology (High-AVT) for HRSG FAC Control

    Naoya Urata,
    Senichi Tsubakizaki,
    Kiyotaka Aoki,
    Yuko Yamamoto,
    Toshifumi Hirasaki,
    Sumiya Iida

    In the combined-cycle heat recovery steam generators (HRSGs) of thermal power plants, tube wall thinning in the economizer occurs because of flow accelerated corrosion (FAC). To verify measures for FAC mitigation such as material change and water treatment optimization, we have developed a heat-resistant thin-film ultrasonic testing (UT) sensor that can be used to measure the wall thickness of high temperature tubes while the unit is in operation. As an assessment of the performance of this technology, we monitored tube wall thinning using our thin-film UT sensor at an actual plant of TEPCO Fuel & Power, Inc., which consequently enabled us to assess the effectiveness of the application of High-AVT water treatment against FAC.