Requirements for the first operation of a centrifugal pump

1. Follow the flowchart to install the pipelines and fittings in place; measure the absolute value of the motor’s parameters, and supply power once they are within acceptable limits; complete the individual testing of the new pump (the individual testing is organized by the general contractor, who forms a testing team, develops a testing plan, and carries out the tests, with the cooperation of the production unit as well as units involved in design, supply, and quality control).
2. The operators must wear appropriate personal protective equipment and prepare all necessary tools and equipment; conduct a thorough inspection of the pump before starting it up.
3. In accordance with the lubrication management procedures, add lubricant to a level of 1/3 to 2/3 of the gauge’s capacity.
4. Open the pressure gauge valve and the pump’s cooling water valve, and check to ensure everything is functioning properly.
5. Close the pump’s outlet valve and the discharge valve, and make sure the inlet valve is fully open before filling the pump.
6. According to the mechanical seal flushing instructions, supply an appropriate amount of flushing fluid for the mechanical seal.
7. Remove the vent plug on the pump body, release any gas from the inlet and within the pump body, then close the vent plug again.
8. Remove the coupling cover and manually rotate the pump shaft in the direction of rotation; check whether the shaft rotates smoothly. For new pumps or pumps that have been overhauled, verify that the concentricity and parallelism of the two couplings are within the specified ranges.
9. Start the motor in intermittent mode to confirm that the rotation direction is correct, then reinstall the coupling cover.
10. Start the centrifugal pump. Once it reaches its rated speed and the pressure stabilizes, slowly open the pump’s outlet valve. Adjust the valve opening so that the pressure and current values remain within the specified range. Note: ① While gradually opening the pump’s outlet valve, pay attention to the motor current, as well as changes in pump outlet pressure and flow rate. If the pressure reading drops suddenly, close the outlet valve immediately and reopen it slowly once the pressure returns to normal levels. ② If a control valve is used to regulate the flow rate at the pump outlet, the outlet stop valve should be fully open. ③ Operating for an extended period with the stop valve closed should be avoided (not exceeding 3 minutes). ④ When starting a new pump for the first time, it is not necessary to increase its speed to the rated level right away; instead, after starting it two or three times, the speed can be gradually increased to the rated level ； ⑤ While the pump is in operation, the inlet valve must be fully open; it is absolutely not allowed to use the suction valve to regulate the pump’s flow rate in order to avoid cavitation. 11. Check the vibration of the front and rear bearings ； 12. Check the packing compression level ； 13. Check whether the pump body and motor produce any abnormal noises ； 14. Check the pump bearing temperature and the motor bearing temperature ； 15. Check the cooling water and lubricating oil systems to ensure there are no leaks ； 16. Check whether the bolts at all connection points are loose, whether the parts that do not rotate are too loose, and whether the temperature is too high ； 17. Are there any unusual smells in or around the pump room or pump? ； 18. No cavitation phenomenon. 19. During pump operation, regularly check the pressure, flow rate, current values, as well as the parameters listed from 11 to 18 above; if any abnormalities are detected, stop the pump immediately, identify the cause, and then resolve it ； 20. Ordinary centrifugal pumps should also be started according to the above procedure in normal operation.

What was said upstairs makes sense! Another point is that the pipes must be purged before starting the pump, to prevent weld slag or metal shavings from entering the pump during pipe welding; additionally, it is advisable to install a filter in front of the pump when starting it up for the first time. I hope it helps a little!

What was said on the first floor is quite accurate and covers most of the points; here are a few additional suggestions that I hope will be helpful to you. 1. Disconnect the coupling and run the motor without a load for more than 2 hours, then check the motor bearings as well as the temperatures of the rotor and stator. 2. For high-temperature pumps, open the preheating valve before starting the pump in order to preheat it, with a preheating rate of less than 50 degrees per hour, until the inlet temperature is at least 50 degrees higher than the temperature of the medium. Before starting the pump, tighten all the bolts in the high-temperature areas at the inlet and outlet of the pump’s cover; after the pump starts operating normally, tighten those bolts again. 3. For shielded centrifugal pumps, if there is a circulation line, it must be opened. 4. For centrifugal pumps driven by turbines, check each item according to the inspection items prior to starting the turbine; after it starts up, check each item according to the inspection items during its operation

May I ask, what is the purpose of running the motor without a load after disconnecting the coupling for over 2 hours, in order to check the motor bearings and the temperatures of the rotor and stator?

First, it is necessary to check whether the direction of rotation of the motor matches that of the pump. The motors are tested before leaving the manufacturer’s facility; they are then sent to the pump factory where they are assembled with the pump on its base, and subsequently delivered to your company for installation in their final location. During these stages, the lubricant inside the bearings can become unevenly distributed due to factors such as gravity and temperature, or certain areas may not be adequately lubricated. This can lead to problems such as motor vibration, abnormal noises, and elevated bearing temperatures. If the motor is tested under load along with the pump, it may cause wear on the bearings and reduce their service life. During transportation and installation, it is possible for the screws securing various components to loosen; if this happens, issues such as vibration and machine shutdowns may occur during idle operation. The main thing to check is whether there are any problems when the motor is operated after installation. It is also important to check the no-load current to ensure that there are no issues such as overcurrent, unbalanced three-phase currents, or missing phases