Start-up Pre-check lists
- Ensure Boiler feed pump is not in permit for maintenance works
- Ensure all the maintenance activities on pumps are completed
- Ensure equipment are normalized from electrical & mechanical side
- Ensure Boiler feed pump is free from obstacles
- Ensure enough lighting or illumination is available there
- Ensure pump coupling is well guarded by robust coupling guard
- Ensure Pumps local field instruments like pressure gauges, switches, vibration sensors, DP gauges are healthy
- Ensure coupling is free to rotate
Start permissive (interlocks)
- Ensure deaerator level is normal
- Ensure feed pumps suction valves is open
- Ensure cooling water line & outlet valves to bearings & mechanical seals are open and also water is circulating through the lines.
- Ensure bearing temperatures are normal
- Ensure bearing vibration showing DCS is zero
- Ensure there is no alarm exists for strainer DP (differential pressure)
- Ensure suction pressure is normal
- Ensure discharge valve of the pump is closed
- Ensure minimum recirculation valve or ARC valve is in open condition
- Ensure balance leak off line valve to deaerator is open (In some valves are not provided to balance leak off line)
- Take clearance from electrical & field person to start the pump
- After getting the clearance from both the team, start the pump by giving minimum set point 80% if it is VFD driven.
- Once the pump started, ensure pump will attain minimum 40% RPM in just 10 seconds (in case of journal bearing pumps).For non-journal bearing pumps speed ramp up time is not recommended specifically.
- During speed ramp up check bearing vibrations & temperatures are normal.
- Ensure pressure in the discharge pressure gauge is increasing slowly & has reached rated pressure at rated speed.
- Then check the vibration, bearing temperatures & sound from pump.
- Check & ensure the correctness of balance leak off line pressure
- Wait for stabilization of the pump, once the pump attained rated parameters, check the motor current, temperature & vibrations & ensure they are within permissive limit.
Also recheck pump bearings vibration, temperatures & any abnormal sound from pump.
Pump normal shutdown procedure
- For VFD driven pumps reduce the pump speed to 80% (for start delta driven pumps speed cannot be reduced)
- Close the pump’s discharge valve
- Then stop the pump
Do not’s for Boiler feed pumps
- Do not rotate the pump in reverse direction, reverse direction leads the seize of pump
- Don not run the pump if its suction water temperature is more than design/required
- Do not operate the pump at less than 80<% load for long time to avoid damage to the bearings
- Do not close the auto recirculation line valve
- Do not close the balance leak off line valve (if provided)
- Do not stop the pump with discharge valve open
- Do not throttle the suction valve of the pump at lower load, can throttle discharge valve
For related articles read
For related articles read