Visual Inspection of Soot Blowers

Soot blowers can be a root cause for deterioration if they are not operating properly. Therefore, soot-blower parts should be inspected for proper alignment, position, and operability. If soot blowers are out of position or misaligned, the blower blast could impinge on tubes which will eventually cause tube failure due to erosion. Soot blowers can also be a source of liquid water that can promote dew point corrosion of tubes, casing and the blowers themselves. The shut-off valve to the blowers should be checked to ensure it does not leak while in service. Condensate can form in the system when the blower is out of service and if it leaks into the firebox can cause dew point corrosion.

The blower, supporting hangers, and brackets should be examined visually for soundness and for excessive thinning from oxidation. Soot blowers for the high-temperature part of the boiler are sometimes composed of high-chromium alloys that embrittle in service and so they should be handled/inspected appropriately to avoid fracture. Connection welds of supporting elements should be inspected for cracks. If the welds look cracked, a magnetic-particle inspection should be made. Packing glands and all operating parts of the rotating and retracting types of soot blowers should be examined for good working condition. Because of the potential difficulty of repacking soot blowers in service, repacking should be done during down periods if there is any evidence that repacking might be required.

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