canned motor pump operating recommendations and precautions
(1) Pre-start inspection
1, check the insulation resistance must be more than 2M.
2, check whether the direction of rotation of the motor and the direction of the arrow on the pump shell is the same.
3, check whether the bearing monitor points to the specified area, the pointer points to the red indicator band is abnormal.
4, check whether the fastening parts are secure, pressure meter, coolant is good to use, the outlet valve and pump exhaust valve is closed and leakage.
5, check that the coolant is on.
(2) The start of the pump
1, the media temperature should be warmed up, the heating rate is 50 degrees C/h, to ensure that all parts of the heat is uniform.
2, fully open the in-in valve, remove the gas inside the pump, so that the line is full of liquid.
3, start the pump, fully discharge the gas inside the pump.
4, after the exhaust, check whether the outlet pressure meter is on the specified pressure, and slowly open the outlet valve, so that the discharge amount to reach the working point flow.
5, check the motor temperature < 70 degrees C.
6, the operation process should pay attention to the pressure difference before and after the coarse filter, if the pressure difference increases too much, to reverse the pump.
(iii) Stop the pump or switch the pump
1, when the media temperature is high, should first cool down, cooling speed of <10 degrees C/min, should be reduced to the liquid temperature below 80 degrees C, before parking.
2, the backup pump according to the open pump procedure, and then slowly close the exit valve, while observing the operation of the backup pump, confirm that there are no abnormalities, shut down the exit valve.
3, press the stop button, stop the pump.
4, close the exit valve.
5, stop coolant.
(4) Precautions for the safe operation of the canned pump
1, in the normal operation process, the closure of the outlet valve is not allowed to shut down, to maintain a micro-open state, in order to prevent air resistance in the pump.
2, strictly prohibited liquid-free operation and more than 30 seconds of off-flow operation, in order to prevent damage to motors and bearings.
3, strictly prohibited reverse operation for more than 30 seconds, reverse operation may lead to abnormal bearing wear.
4, strictly prohibited in the air corrosion state of operation, pump in the air erosion state, will lead to early wear of bearings.
(5) Daily maintenance
1, to often check the smooth flow of coolant, to ensure that the surface temperature of the pump does not exceed the specified value, but also pay attention to water conservation.
2, to often check the TRG instructions, such as the occurrence of exceptions to deal with decisively.
3, check the pressure indication, the inlet filter blockage, if necessary to clean.
4, check the operation of sound, vibration, leakage and other abnormal conditions and to deal with.
5, to adjust the outlet valve to ensure that it is not overloaded operation.
6, canned motor pump fault treatment reference TRG instructions and canned pump failure and its causes and solutions.
7, long-term deactivation should be pump coolant, media blow clean to ensure that it does not rust and freeze.
(6) The common faults and treatment of canned pumps
1, graphite bearing damage
Cause: cavitation, shaft movement, graphite cracking.
Handling: Switch pumps and replace bearings.
2, the pump can not start
Cause: Media crystallization or low temperature viscosity.
Treatment: Switch pumps to increase pump body temperature.
3, the pump body overheating
Cause: The cavitation or cooling water is interrupted.
Treatment: Identify the cause of the elimination of cavitation;
4. Vibration or noise
Cause: cavitation or bearing wear.
Treatment: identify the cause of the elimination of cavitation, switch pump replacement bearings.
5, export pressure is low
Cause: cavitation, impurity damage, impurities blocked at the entrance.