SHORTFALL IN COMMISSIONING OF BOILER
As a Commissioning professional, lot of unexpected things are experienced during the Commissioning of Boiler, which are never recorded but leave behind a great impact in terms of performance, money and failures.
Commissioning takes own time without bypassing the events, but there is always shortage of time from both end i.e. SELLER & PURCHASER. This shortage of time is always beneficial to SELLER as anyhow activity is completed.
Commissioning of Boiler require a systematic approach in a planned & recorded way to start plant in a perfect manner. Actually, there is a normal tendency to neglect the systematic & sequential approach during commissioning on behalf of urgency.
Defects Noticed during & after Commissioning of Boiler:-
- Piping Supports misalignment & uneven loading in hot condition
- Shifting of Piping / Piping Support from its original position
- Water carryover in PRDS piping after de-superheating section
- High Spray water flow to control Main Steam temperature
- Uneven Thermal Expansion of Pressure Parts / Casing
- Abnormal Vibration in Pressure Parts / Casing / Ducting
- Heavy Fluctuation in Drum level, Furnace Draft
- High back end temperature (Flue Gas Temperature at APH Outlet)
- Maximum Loading of Fans & Blowers
- High Emission/SPM from ESP / Bag Filter
- High Un-burnt Carbon in Fly Ash / Bottom Ash
- Inadequate drain piping of PRDS, Soot Blowers, Control Stations
- Secondary Combustion in Superheater Zone
- Bed Material slippage in Wind box / Bed material shifting on grid floor
- Water carryover from Deaerator Air/Gas Vents
- Water ingress in Insulation
- Improper fixing of Insulation & Cladding
- High insulation cladding surface temperature w.r.t. design
- High sound decibel form equipments / silencer
- High Auxiliary Power Consumption w.r.t. individual equipment
- Less Difference of Pressure in-between Steam Drum & Boiler Feed pump discharge to adjust power consumption
- No Approach for Valves, Dampers, Instruments, O&M Work
- Non availability of Inter-connecting platform, Safe working platform
Mandatory steps for commissioning of Boiler are described in details in attachment (Under mentioned steps are bypassed / clubbed with each other to reduce time span/unavailability of resources and inputs/incompetent personnel/low priority client)
- Pre Commissioning
- Cold commissioning
- Hot Commissioning
Read details in attachment