Recent Completed Project on ‘Risk Based Inspection and Remaining Life Assessment of a Boiler for an Asian Power Plant’

ETD were approached to submit a proposal on ‘Risk Based Inspection (RBI) and Remaining Life Assessment (RLA) of one of the client’s boilers by performing on-site inspection, analysis and assessment on tubes, T-piece nozzles, stub tube weldments and hot reheat pipe weldment for FSOH and ROH.

The work involved performing on-site inspections - ultrasonic measurements (UT) of tube wall & bore oxide scale thickness, replication, hardness measurement, wet fluorescent magnetic particle test and advance UT phased array of selected components from FSOH and ROH. The inspection data was then used to estimate tube metal temperature and identify material degradation. This was then used for damage assessment and predicting the remaining life of outlet headers and tubes of final superheater and reheater. The previous inspection and maintenance data for other pressure parts (i.e. economiser, etc) were also reviewed and analysed to complete remaining life assessment of the boiler.

For more information about ETD’s Remaining Life Assessment services, please click here.

Risk Based Inspection and Remaining Life Assessment of a Boiler for a Power Plant

ETD recently performed Risk Based Inspection and Remaining Life Assessment of a Boiler for a Power Plant in Europe.

The work carried out included: 

  • Reviewing the drawings of FSOH & ROH, tube banks of the boiler to be studied and identifying accessible test locations for on-site inspections.
  • Performing on-site ultrasonic thickness (UT) measurement of tube wall thickness and bore oxide scale considering 50% of total tubes for FSOH & 40% of total tubes for ROH;
  • Performing on-site replication and hardness measurements on straight tubes, T-piece nozzle weldments, stub tube weldments and hot reaheat pipe weldment for FSOH & ROH;
  • Performing on-site wet fluorescent magnetic particle tests on T-piece nozzle weldments and stub tube weldments for FSOH & ROH;
  • Performing on-site advanced UT phased array on T-piece nozzle to main steam pipe weldment for FSOH and hot reaheat pipe weldment for ROH;
  • Assessment of all replicas by using OM (optical microscope) and to confirm the damage condition, further assessment of selected P/T/F91 & T23 replicas by using SEM (Scanning Electron Microscope) and if necessary, to confirm the damage condition, further assessment of selected P/T/F91 replicas by using ETD’s SFM (Scanning Force Microscope) at ETD lab;
  • Assessment of damage and material degradation of outlet headers, tubes, T-piece nozzle weldments, stub tube weldments and hot reaheat pipe weldments for FSOH & ROH based on the replication and hardness measurements data;
  • Review and interpretation of wet fluorescent magnetic particle tests data and UT phased array inspection data to assess any presence of surface and/or internal cracks/ defects;
  • Reviewing & interpretation of UT inspection data and estimation of wall thickness loss & tube metal temperature;
  • Assessment of the remaining life of FSOH & ROH components based on estimated tube metal temperature and other inspection data;
  • Reviewing & analysing previous failures, inspection and maintenance data for other pressure parts (i.e. economiser, etc) of the boiler to complete the life assessment study;
  •  Preparing a full report including the results of on-site inspections, analysis results of damage & life assessment study and make recommendations for any further actions to be taken by the client for safe and reliable operation of the boiler.

For more information about our Risk Based Inspection & Remaining Life Assessment services, please click here.