Centrifugal pump start step should be: first, all the imported valve to open, close the outlet valve, start the motor, after the normal speed, can gradually open the outlet valve, adjust to the required conditions.
Correct operation method of centrifugal pump
The operation of the centrifugal pump can be divided into three steps, namely, start, run, stop.
Start: before the start should be prepared to do the following:
(1) check the water pump equipment in good condition.
(2) bearing oil, the oil level is normal, oil quality
(3) the inlet valve of the centrifugal pump is fully opened.
(4) filling water in the pump or vacuum pump (except water intrusion) open exhaust valve.
(5) check the seal Water Leakage, packing a little drop of water is appropriate.
(6) the motor rotation direction is correct.
After the above preparations are completed, the motor can be started, after the speed is normal, check the pressure, current and pay attention to whether there is no vibration and noise. Everything is normal, and gradually open the valve, the required conditions to adjust the valve clearance, note idling time should not exceed 3 minutes.
Run: during the operation, the main circuit inspection, check the contents of four aspects:
1, check the bearing
(1) the bearing temperature is less than 75 DEG C.
(2) the bearing chamber can not influent the impurities, oil can not be emulsified or black.
(3) rolling thin oil lubrication, the oil should not be less than the center line.
(4) if there is abnormal sound, bearing damage generally appear abnormal sound.
2, vacuum gauge, pressure gauge, ammeter reading is normal
(1) vacuum gauge can not swing too large, too large may make the pump entrance vaporization occurs, another vacuum meter reading can not be too high, too high may block the entrance valve, stuck or pool water absorption decreased.
(2) the export pressure gauge reading is too low, may be the sealing ring and the guide vane sleeve wear. The stator and rotor clearance is too large, or the outlet valve to open too large, large flow and low lift.
(3) the current meter reading is too large, may be traffic, or between the stator and rotor friction.
3, whether the pump units produce greater vibration and vibration causes are:
(1) pump and motor axis misalignment.
(2) the pump or motor foot bolt loose, or without a solid foundation.
(3) unbalance.
(4) pump operation in small flow, radial force, reflux, cavitation.
4, the sealing work is normal
(1) no K shape dynamic seal leakage during normal operation.
(2) a cooling water device, to check whether the normal flow.
Stop pump
(1) centrifugal pump to stop should first close the outlet valve, to prevent the non-return valve failure cause the outlet pressure water intrusion into the pump, causing impeller reversal and cause damage to the pump.
(2) when the pump stops if the inertia is small, i.e. when the power pump stopped quickly, that in Mocha or the phenomenon of eccentric pump.
Conclusion: centrifugal pump start and stop running, three steps are very important, but the most important thing is to adjust the outlet valve. If the ceiling on state, the outlet valve open degree is relatively large, if the state intrusion, outlet valve of a relatively small number. Design of outlet valve adjustment work point is close to the pump as possible, so that the actual flow and design theory to coincide, the operation efficiency of pump, saving resources. Because of the high point of the pump in the vicinity of the design point and design point of course, ultimately to a current overload as a precondition.
Due to the centrifugal pump to start when, in the outlet pipe of the pump is not water, so there is no pipeline drag and lift a high degree of resistance, after starting the pump, the pump head is very low, the flow is very big, this time pump motor shaft power output (according to the pump performance curve), it is easy to overload, will make pump motor and circuit damage, therefore starts to close the outlet valve, in order to make the normal operation of the pump.
