Nalco Guide To Boiler Failure Analysis -
"Every failure has a fingerprint. The goal is not to replace the tube, but to eliminate the mechanism." The guide categorizes failures not just by appearance, but by the underlying stressor: corrosion, fatigue, creep, or a combination thereof.
This is structured as an internal technical brief or an educational overview for plant engineers and maintenance teams. Introduction Boiler failures remain a leading cause of unplanned outages, safety hazards, and costly repairs in power generation and industrial steam systems. The NALCO Guide to Boiler Failure Analysis (often referenced as the industry standard text by the late James R. ("Dick") Rees and NALCO Chemical Company) provides a systematic, root-cause methodology for diagnosing tube failures. Unlike generic metallurgical reports, the NALCO approach emphasizes the interaction between water chemistry, heat transfer, and material science . nalco guide to boiler failure analysis
| Step | Action | |------|--------| | 1 | – Document fracture orientation, internal deposits, wall thinning. | | 2 | Deposit Analysis – Measure deposit weight density (g/ft²). Identify composition (Fe, Cu, Si, Ca, P). | | 3 | Metallography – Examine cross-section for decarburization, intergranular attack, or spheroidization. | | 4 | Water Chemistry Review – Compare historical pH, conductivity, O₂, and phosphate trends. | | 5 | Operational Correlation – Match failure timeline to startup events, low-water trips, or chemical upsets. | "Every failure has a fingerprint
