Dexon TechnologyDexon Technology recently inspected three feedwater heaters at a thermal power plant in Laos, completing their work within the narrow shutdown window.
For those outside the power industry, feedwater heaters are among the quiet workhorses of a thermal power plant. Their job is to recover heat from steam that has already passed through the turbine and is repurposed it to heat incoming water.
By recycling this energy, the plant burns less fuel to produce more electricity.
Inside each heater can be thousands of small tubes carrying water and steam. Together, these tubes can provide a heat-transfer area equivalent to several tennis courts, allowing the recovery of enormous amounts of energy within a compact vessel.
Because these systems contain so many individual tubes, though, a single failed tube can affect the performance of the entire unit.
Identifying issues early allows operators to plug damaged tubes, schedule repairs, and prevent minor defects from becoming a major shutdown.
Our engineers combined several complementary techniques, executed by four teams, to complete the inspection during the shutdown period:
• Remote Field Testing (RFT) for rapid screening of tube condition
• IRIS (Internal Rotating Inspection System) for highly accurate wall thickness measurements
• Remote Visual Inspection (RVI) to identify surface damage and support defect evaluation
The inspection was completed within the allotted time and allowed operators to identify degradation mechanisms, prioritize repairs, and better understand how operating conditions contributed to tube damage.