BOILER FAILURE ANALYSIS & RECOMMENDATION

Trouble starts with the start of a New Boiler and complete elimination is like a daydream. We need to accommodate and survive with best operational & efficiency parameters and minimum failure and downtime

    A LIST of CHRONIC TROUBLES & REASONS
  1. Erosion of Tubes in Bed Coils
    1. Two phase Flow Accelerated Corrosion – FAC in Bed Coils due to improper / disturbed circulation, Tube failed at Upper Half Portion in Bottom Coil
    2. High Bed Fluidization gas velocity (maximum allowed < 2.5m/s)

MAJORITY OF BED COIL FAILURES DUE TO IMPROPER CIRCULATION & FLOW ACCELERATED CORROSION (FAC)

  1. AFBC BOILER - WORKING PRESSURE 87KG/CM2g

    This is not Caustic Gouging, it’s TWO PHASE FAC.

    Boiler Water Chemistry used is All Volatile Treatment

    Bed Coil Failure, Mainly due to Improper/Disturbed Circulation & High Heat Flux by High GCV Imported Coal firing,

    Corrected by RIFLE TUBES. Tube failed location is exactly 12 O’clock position

  2. AFBC BOILER - WORKING PRESSURE 67KG/CM2g

    This is not Caustic Gouging, it’s TWO PHASE FAC.

    Boiler Water Chemistry used is All Volatile Treatment

    Bed Coil Failure, Mainly due to Improper / Disturbed Circulation & High Heat Flux with Rice Husk firing

    3. NOTE: Most of the Improper / Disturbed Circulation Failures are converted to Erosion Failures to avoid design failure highlights.

  3. STOKER FIRED BOILER - WORKING PRESSURE 45 KG/CM2g

    This is not Caustic Gouging, it’s TWO PHASE FAC.

    Boiler Water Chemistry used is All Volatile Treatment

    Riser going to Steam Drum Failure, Mainly due to Improper Circulation, Piping layout with more bends, Corrected by change in Riser Piping Material from Carbon Steel to Alloy Steel.

  4. Erosion of Tubes in Boiler Bank, Evaporator
    1. High Flue gas velocity (maximum allowed <18 m/s)
    2. Improper sealing of Bank tubes & Fin plate with drum
    3. Wrong location & design of Flue gas partition plate
  5. Ash Accumulation in Goose-Neck, Superheater & Gas Outlet Duct
    1. Less Gap in-between Goose-neck tubes & Superheater bottom
    2. Channeling & Improper Gas distribution across Superheater
    3. Secondary combustion in Superheater Zone
  6. High Steam Temperature Superheater Pickup
    1. Fuel carryover & combustion in Superheater Zone
    2. Change in Free board combustion area in AFBC Boiler

M/s Unite Energy Corporation LLP is keen to provide the Spares, Sales & Services, Retrofit & Site Repairs of Boiler & Auxiliaries, Performance Evaluation, Shop & Site Fabrication, Erection & Commissioning, Design Modification & Feasibility Study, Consultancy & troubleshooting support to mitigate the irregularities in the plant, minimize breakdown & downtime and improvise design & system performance to improve the overall plant's health and performance.

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