Steps to start a canned motor pump

Operating Procedures for Shielded Pumps I. Operating Procedures 1. Pre-startup inspections 1) Check whether the pump’s foot bolts are tightened properly. 2) Check whether the flange gaskets at the pump’s inlet and outlet are appropriate, and whether the flanges are properly tightened. 3) Check whether the pressure gauge of the pump is installed, and whether its installation location and pressure rating meet the requirements. 4) Check that the motor’s grounding wire is connected and tightened properly. 5) Check whether the pump’s flushing line is loose and whether it is easy to operate for installation. 6) Check whether the area around the pump is clean, free of debris and oil stains; if so, it must be cleaned thoroughly to avoid affecting operation. 2. Preparatory work before startup: 1) Ensure that the process conditions are met – open the pump inlet valve, as well as the pump outlet vent valve and the minimum reflux line; fill the pump with liquid, and open the two drain hand valves at the end of the cooling and flushing pipeline of the shield to release air. 2) Open the motor cooling water jacket and the water used to flush it, establish a cooling water circulation, and ensure that the temperature of the cooling water inlet is no higher than 35°C. 3) Confirm that the motor is powered on and the TRG gauge is in good condition. 4) Install the pressure gauge and check whether it shows normal readings. 3. Test run of the pump: 1) Ensure that the inlet valve is open, the outlet valve is closed, and the minimum return line is open. 2) Press the motor button to start the motor. 3) Slightly open the outlet valve. 4) Check the pump outlet pressure indicator. 5) Check whether the TRG table indications are normal (refer to the TRG table indication instructions). ①If the TRG table pointer is outside the range, it indicates that the motor is rotating in reverse; please power off and correct the wiring. ②If the TRG table pointer is in the yellow or red area, it indicates that there is a fault with the motor; please identify the cause, resolve the fault, and then operate the machine. ③The TRG table pointer is in the green area, indicating that the motor is operating normally. 6) Keep the outlet valve open, run the pump for 2 minutes, then stop it, and bleed air from all parts of the pump again. 4. Operation of the pump: 1) Confirm it is ready, then start the motor. 2) Slowly open the pump outlet valve and the minimum return line valve, and adjust the outlet flow to the specified value. 3) Check whether the motor current is within limits. 4) Check whether the outlet pressure gauge is within the specified range. 5) Check whether the TRG table readings are normal. 6) Are there any abnormalities in the operating noise and vibration? II. Instructions for the TRG table. TRG gauge indication and electric pump status, possible faults, inspection or troubleshooting methods: The gauge pointer increases gradually, the pointer does not move, or the operation condition is poor. The supply voltage increases or bearing wear increases. First, check whether the terminal voltage is normal, then check for bearing wear; if the values are beyond the acceptable range, replace the bearings. The hand of the clock moves irregularly, the flow rate and pressure of the electric pump are unstable, abnormal noises are heard from within, or the motor heats up in certain areas. The circulatory system is abnormal, with insufficient flow or bubbles present. Inspect the circulating fluid pipeline and check whether the type of electric pump meets the process requirements. The hand suddenly rises into the red area, its amplitude of movement increases, with regular fluctuations; sometimes the problem disappears after the machine is shut down and restarted. The expansion of the rotor cage bars causes localized bar breaks. Replace with a rotor of the same model. The gauge needle suddenly rose into the red area; its oscillation amplitude increased, with regular fluctuations, accompanied by abnormal noises from the pump. Impeller shaking, shaft bending, wear of the mouth ring. Disassemble for inspection. When the pointer reading is greater than 0.75, operation is not smooth, and flow rate and pressure are low. The power supply phase sequence is reversed. Check the power supply phase sequence and reconnect the power supply. The hand moves normally, but not smoothly; flow and pressure are low ； Or it is operating normally, with the needle value exceeding 0.75. The phase sequence of the module’s three-phase power supply does not match that of the motor terminals. The TRG is connected incorrectly to the heating element circuit. Check whether the phase sequence of the three-phase power cable of the module matches that of the motor’s power cable, and connect them in the correct phase sequence. The hand indicates 0.5, meaning the voltage of one phase is zero. Open phase. Check the power cable. The hand movement indicates values that fluctuate greatly ； Or it sways, and this phenomenon is brief. Foreign objects have mixed into the pipeline, or the medium contains crystals and precipitates. Check the condition of the medium as well as the heat tracing. The electric pump is working properly; the power cable is connected reversely, and the gauge pointer remains above 0.75 at all times. Sometimes it stops running for a while, after which it starts up again and the fault disappears. The module or TRG table is damaged, or there is a ground fault in the TRG system circuit. Check the input and output electrical parameters of the module, check the meter setting parameters, and verify whether the module and the TRG meter are grounded. The hand does not indicate anything or indicates in the opposite direction. The module polarity is reversed ； Instrument damage, incorrect module selection. Check the selection of instrument module types, as well as the correspondence between the module mounting holes and the polarity of the instruments. The hand of the clock stays still at a certain position. Pin repair: The insulation of the main circuit terminals with respect to ground is zero, or the pump trips when started. The terminal block is damaged, the module is damaged, the main winding is damaged, and there are wiring errors in the TRG meter and the thermal element. Remove the module and the main winding from the terminal block and inspect them separately. III. Precautions for Use 1. Operation without load is strictly prohibited. 2. Ensure thorough exhaust before starting the pump. 3. The flow interruption rotation shall not exceed 30 seconds. 4. It shall not be operated in reverse continuously. 5. The pump must not be started before the cooling water is put into use. 6. If any abnormal phenomena occur during operation, the pump should be stopped immediately for handling. 7. If the TRG gauge is in the red area, operation is prohibited. 8. Operation is not allowed when the flow rate is below the minimum value. 9. The pump is not allowed to be started when the cooling water flow rate is below the required value. 10. The ambient temperature should be between -20°C and 40°C, with humidity not exceeding 85% (25), along with the specified explosion-proof marking. 11. Be sure to prevent pressure from being released when the pump is venting. 12. The temperature of the electric pump rises during operation; do not touch it with your hands. 13. When the overcurrent relay and thermal element activate, it is necessary to find the cause before restarting.

The second floor is very detailed; it’s just like our method of operation!

A new system is about to be put into use, with over 100 shielded pumps – it would be useful to draw lessons from that

For vertical LPG shielded pumps, one additional requirement is to activate the reverse circulation line before starting the pump; if this line is equipped with a flow control orifice plate, the valve must be fully open； If this line is a flow meter, the opening of the flow control valve shall be adjusted according to the specified flow rate.

Thank you for what was provided on the second floor; it’s perfect for reference.

I have a question: is this minimum return path necessary?