KGE-200

Common issues

• Soot accumulation leading to reduced heat transfer efficiency and increased soot fire risk.
• Fin tube erosion, particularly in high gas velocity areas or due to abrasive particles.
• Bypass damper malfunction (sticking, incomplete closing/opening, linkage failure) affecting temperature control.
• Tube leaks on the water side due to erosion, corrosion, or thermal stress.
• Exhaust gas side corrosion, especially low-temperature corrosion if gas temperatures drop below dew point.
• Casing leaks (gas side) leading to heat loss and potential gas ingress into machinery spaces.

Inspection checklist

• Visual inspection of fin tubes for signs of erosion, cracks, deformation, and excessive soot deposits (during internal access).
• Check bypass damper operation, linkages, bearings, and blade sealing effectiveness for smooth and full travel.
• Verify soot blower functionality, nozzle condition, and steam/air supply pressure.
• Inspect the economizer casing for gas leaks, insulation damage, foundation integrity, and access door sealing.
• Monitor exhaust gas inlet and outlet temperature differential to assess heat transfer efficiency.
• Check water side pressure gauges, thermometers, and safety valve for proper function and calibration status.
• Inspect for any signs of water leakage from tubes, headers, or drain lines.
• Verify proper operation of drain lines and soot collection points, ensuring no blockages.

Service intervals

Typical wear limits

Ranges are typical for this design class. Always confirm against the manufacturer documentation for your serial number.

Critical spares

• Soot blower nozzles and lance tubes.
• Bypass damper actuator components (e.g., pneumatic cylinder seals, positioner, linkages).
• Fin tube sections (for emergency repairs, minimum 2-3 lengths).
• Gaskets for access doors, manholes, and critical flanges.
• Safety valve overhaul kit or complete spare valve.
• Pressure gauges and thermometers for critical points (water inlet/outlet, gas inlet/outlet).

Safety

• Soot fire: High risk of ignition of accumulated soot, leading to structural damage and potential fire spread.
• Exhaust gas leakage: Danger of toxic gas release into machinery spaces, leading to asphyxiation or fire hazard.
• Overpressure on water side: Failure of safety valve to lift can lead to catastrophic rupture of pressure parts.
• Hot surfaces: Risk of burns from uninsulated or damaged casing/piping.
• Bypass damper failure: Can lead to uncontrolled heat transfer, potentially damaging downstream exhaust components or causing localized overheating.

Class survey

During annual surveys, surveyors will check external condition, safety valve certification, and operational parameters. For special surveys (typically every 5 years), an internal inspection of the gas side (fin tubes, tube sheets, soot blowers, bypass damper) is mandatory to assess erosion, corrosion, and structural integrity. Water side internal inspection may be required based on water treatment history and operational issues. Verification of soot blowing procedures, exhaust gas temperature monitoring, and safety valve functionality (operational test) is also standard. Documentation of maintenance, repairs, and water treatment logs are thoroughly reviewed.