GN 012.51 - Corrosion and Leaks in Carbon Steel Roof Tubes in Water Tube Boiler
- Details
- Category: Use & In-Service Inspection
| APEK - AICIP GUIDANCE NOTE |
SIGNS OR INDICATIONS IN IN-SERVICE CORROSION AND LEAKS IN CARBON STEEL ROOF TUBES IN WATER TUBE BOILER |
APEK GN 012.51 Rev 0 |
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1 Figure |
 |
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2 PE involved |
D-Type water tube carbon steel boiler. |
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3 Sign(s) |
Leakage, and local rust stain. |
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4 Location of Signs |
In bottom of horizontal roof tubes – carbon steel (std) mm thick, DN50. |
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5 When & Where occurred |
In approx. 2008; near Australia. |
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6 Detection & Investigation |
Loss of water, excessive make-up, and VT. |
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7 Failure mode(s) (damage mechanisms) |
Corrosion, Chloride and O2 pitting. |
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8 Most probable causes |
Use of sea water for water make-up. Inadequate water quality. High water temperature in roof tube and possible deposits where corrosion worst. |
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9 Outcome |
New boiler or possibly completely re-tube of drums if they are in reasonable condition. |
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10 Most Possible Prevention |
Proper feed water and treatment and management. |
SAA