High-Temperature Tube Life Prediction with LIFECODE

Typical Output Screen for LIFECODE, Showing UT Signal and Remaining Life Predictions

The Problem: SH/RH tubing is designed with a finite life. As boilers age these tubes fail, causing costly unplanned outages. Wholesale replacements can unnecessary replace tubes with decades of reliable service remaining.

The Solution: Accurately predict the remaining life of individual tube elements by measuring critical tube dimensions .

To implement this solution, SI ultrasonically measures tube wall and internal oxide scale thickness and predicts remaining tube life using LIFECODE software. The ultrasonic field measurements are achieved by use of focused UT technology and TestPro™, a PC-based digital UT system.

SI's system can be purchased, or we can provide the testing service, which includes the following deliverables:

1. Prior to inspection, SI performs a unit review and tabulates unit operating hours and cycles, section design, tubing materials, historical tube failure data, and the results of previous assessments to identify critical inspection areas.
2. After the inspection, SI provides a preliminary report documenting tube dimensional data and remaining life estimates before leaving the site. These results are finalized and all output printouts are provided in the final report.
3. SI also provides the data obtained in the field in electronic format for use as a baseline for future inspections and independent assessment.

LIFECODE contains algorithms that allow the user to make probabilistic, as well as deterministic, estimates of tube remaining life. It also contains algorithms to project the effectiveness of chemical cleaning in extending tube remaining life.

"By using the ID oxide and wall thickness data acquired by SI's TestPro system, we have been able to quickly ascertain the overall condition of our high temperature tube components, and focus repairs on areas that need it, rather than blindly replacing entire components."
Richard A. Coutant, Progress Energy