Troubleshooting of common accidents of industrial boiler feed water pump
1. Emergency stop pump regulations:
(1) The bearing temperature of the industrial boiler feedwater pump set or the temperature of the motor housing rises sharply, exceeding the limit value.
(2) The motor and pump body vibrate strongly, or the sound of metal impact or friction is heard clearly.
(3) The indication of the feed water pump ammeter obviously exceeds the rated value or swings greatly.
(4) Smoke or fire from the feed pump motor of the industrial boiler.
(5) The pipe and valve flange of the feedwater pump were broken, the pipe was broken, a lot of water was sprayed, and it could not be operated.
Industrial boiler feed water pump
2, industrial boiler feed water pump bearing temperature rises
Failure phenomenon:
(1) Feeling hot when touching the bearing.
(2) Abnormal bearing sound and increased vibration.
cause of issue:
(1) The bearing oil level is too low.
(2) The oil quality has deteriorated or there is water in the oil.
(3) Insufficient or interrupted bearing cooling water.
(4) Heat transfer effects of other parts.
(5) The bearing is damaged, and the bearing assembly clearance or tightness does not meet the requirements.
Approach:
(1) Strengthen roving inspections and refuel in time.
(2) If the oil quality has deteriorated, analyze the reasons for the oil deterioration and change the oil in time.
(3) Regularly adjust the bearing cooling water volume, dredge the cooling water pipe, and adjust the pump if necessary.
(4) If the bearing temperature rises to the maximum allowable value or is accompanied by abnormal noise and vibration, the pump should be stopped immediately for inspection.
3, give the industrial boiler feed water pump group bearing vibration
Failure phenomenon:
(1) Hand touch and feel the vibration is significantly larger than normal.
(2) There is an abnormal sound.
(3) The measured amplitude of the vibration meter exceeds the specified value.
(4) The bearing temperature has increased.
(5) The ammeter indicates an increase or exceeds the rated value.
cause of issue:
(1) The center of the feed water pump and the motor are not accurate.
(2) The backrest wheel screw is loose or broken, and the foot screw is loose.
(3) Bearing tightness or clearance is not up to the requirements, bearing damage.
(4) The rotating parts are loose or damaged, and the balance plate is worn.
(5) There is debris in the pump impeller.
Approach:
After the vibration exceeds the rated value, the report value is long, and the pump should be adjusted and run immediately.
4, industrial boiler feed water pump motor current increases
Failure phenomenon:
(1) The ammeter indicates an increase and exceeds the rated value.
(2) The ammeter indication rises and swings greatly.
(3) There is abnormal sound from the pump unit.
(4) The vibration of the pump set increases.
(5) The feed water pressure is reduced.
cause of issue:
(1) The pressure of the feedwater pipe decreases, the flow rate of the feedwater pump increases, and the operation exceeds the force.
(2) Packing is too tight after overhaul, bearing failure and damage.
(3) The motor is running under phase loss.
(4) The voltage is too low and the frequency is too high.
(5) The inside of the pump unit is rubbed, sundries are dropped, and the balance plate is worn.
Approach:
(1) If the motor current exceeds the rated value due to excessive operation, a standby pump should be added.
(2) If the operation is due to an overcurrent failure or the safety of the equipment may be affected, the standby pump should be opened and the failed pump should be stopped.
5. Industrial boiler feed water pump vaporization
Failure phenomenon:
(1) The ammeter indication decreases.
(2) The feed water pressure is reduced.
(3) There is noise or water hammer in the pump or water inlet pipe.
cause of issue:
(1) The water level of the deaerator is too low, and the water temperature of the deaerator is too high.
(2) A sudden drop in the internal pressure of the deaerator (the inlet valve closes by mistake, improper adjustment or unit load rejection).
(3) The running time of the feed water pump at no load or low load is too long, and the recirculation door is not opened or the opening is small.
(4) The feed water pump inlet is too small or the inlet filter screen of the feed water pump is blocked, and the valve core of the feed water pump inlet line valve falls off.
(5) The parallel pump operation is improper.
Approach:
(1) Ensure that the temperature, pressure and water level of the deaerator water tank are within the normal range.
(2) Open the recirculation door and adjust its opening to a suitable position when the test pump or parallel pump is running.
(3) If the pressure of the feedwater pipe is found to be too high during operation, the recirculation door should be opened appropriately.
(4) If the inlet filter of the pump is blocked, adjust the pump immediately.
(5) If the valve core of the feedwater pump inlet pipe falls off, adjust the pump immediately.
6, the feed water pressure of the industrial boiler feed pump is reduced
Failure phenomenon:
(1) The pressure in the feed jellyfish pipe is reduced.
(2) The boiler drum water level is low.
(3) Increase or swing to the pump current.
cause of issue:
(1) Boiler steam pressure changes.
(2) Improper adjustment of the boiler.
(3) Boiler blowdown is too large.
(4) A large amount of water leaks in the water supply system.
(5) Feed water pump failure, motor trip switch or power supply interruption.
(6) System misoperation.
Approach:
(1) When the pressure of the water supply pipe drops to about 6.5MPa, immediately report to the shift leader, contact the boiler, and prepare to activate the standby pump.
(2) When the pressure of the main pipe drops to 6.0 MPa, the low water pressure interlock should act, and the standby pump should be able to switch on automatically. If the low water pressure interlock does not work, the standby pump should be closed immediately. And report to the shift leader, and find the cause together with the boiler.
(3) Turn on the standby pump and stop the failed pump.
7, the power supply of the industrial boiler feed water pump is interrupted
Failure phenomenon:
(1) The running sound of the feed water pump changes suddenly, and there is no obvious impact sound under normal circumstances.
(2) All or part of the AC lighting is off.
(3) The pressure of the feed jellyfish pipe is reduced.
(4) The pressure and current of the feed water pump reach zero.
cause of issue:
(1) All plant power supply was interrupted.
(2) Some plant changes, plant failures or AC power failure of a single pump.
(3) Improper switching operations by electrical operators.
Approach:
(1) Put in the standby pump immediately and try to ensure normal water supply.
(2) It is not necessary to open the switch of the original operation pump within a few minutes.
(3) When the standby pump switches are all closed and still invalid, keep the pump in the closed position and wait for the power to recover.
(4) Report to the chief officer and contact relevant personnel for emergency treatment.
