Analysis of superheater tubes degradation at a tangentially fired pulverized coal power plant

Abstract

Thinning of boiler tubing is one of common failure mechanism of coal-based boiler unit. An ultrasonic thickness testing (UT) is typically used to determine the state of boiler tube thickness and is done during a yearly overhaul. The usefulness of thickness data can be problematic due to some fluctuation and irregularities in the data. In the present work, UT data from 4 years inspection will be analyzed with the aim to understand the fundamental mechanism for thinning of the superheater tube. Some part of the UT data is analyzed to obtain the thinning rate of the superheater tube. The thinning trend is the basis for predicting the value of thickness and compared with actual measurement values. The predicted and actual values were tested with statistical operation to observe the significant difference between both values and also the quality of prediction.Thinning of boiler tubing is one of common failure mechanism of coal-based boiler unit. An ultrasonic thickness testing (UT) is typically used to determine the state of boiler tube thickness and is done during a yearly overhaul. The usefulness of thickness data can be problematic due to some fluctuation and irregularities in the data. In the present work, UT data from 4 years inspection will be analyzed with the aim to understand the fundamental mechanism for thinning of the superheater tube. Some part of the UT data is analyzed to obtain the thinning rate of the superheater tube. The thinning trend is the basis for predicting the value of thickness and compared with actual measurement values. The predicted and actual values were tested with statistical operation to observe the significant difference between both values and also the quality of prediction.