Installation Precautions for Light Horizontal Multistage Pumps
Light horizontal multistage pumps are a type of multistage centrifugal pump. The structure of multistage centrifugal pumps generally includes vertical multistage centrifugal pumps and horizontal multistage centrifugal pumps. When installing horizontal multistage centrifugal pumps, there are some precautions that need special attention. Before installing a light horizontal multistage centrifugal pump, carefully inspect the exterior of the pump body for any obvious defects or damage. During the installation of multistage pumps, the weight of the pipeline should not be forcibly applied to the pump body, and separate supports are required (which need to be purchased separately).
1. Before installing a light horizontal multistage pump, carefully check the pump passages for any hard objects that may affect the operation of the multistage pump, such as iron sand or stones, and remove them immediately if found.
2. The weight of the pipeline during installation should not be borne by the horizontal multistage centrifugal pump, as this can easily lead to damage to the pump.
3. When installing, tighten the anchor bolts, and check them at regular intervals to prevent loosening, which can prevent severe vibration during startup and affect its performance.
4. When a horizontal multistage centrifugal pump is used in a suction-lift application, a foot valve should be installed, and the inlet and outlet pipelines should not have too many bends. Air and water leakage should be avoided during operation to prevent affecting the performance of the light horizontal multistage pump.
5. Before installing the pipeline, gently rotate the rotor components of the multistage centrifugal pump. There should be no obvious jamming or friction. Otherwise, the pump should be removed for inspection and troubleshooting.
6. To prevent foreign objects from blocking the flow passages and affecting the performance of the multistage pump, a filter device should be installed in front of the multistage centrifugal pump.
7. For safety and easy maintenance, a regulating valve can be installed on the inlet and outlet pipelines of the light horizontal multistage pump, and a pressure gauge can be installed near the inlet and outlet of the multistage pump. For high-head pumps, to prevent water hammering in the event of sudden power failure, a check valve should be installed before the outlet valve to handle sudden emergencies, ensuring that the horizontal multistage centrifugal pump operates under ideal conditions.
The impeller of a multistage centrifugal pump consists of two or more components, while a single-stage centrifugal pump has only one impeller. The main components of a vertical multistage centrifugal pump include multiple impellers, inlet and outlet sections, and discharge sections.
Operating Precautions for Multistage Centrifugal Pumps
Light horizontal multistage centrifugal pumps should not be operated without water, as this can adversely affect their performance. Before operating a horizontal multistage centrifugal pump, ensure that the pump is filled with sufficient liquid, and expel any air through the exhaust vent. Pay attention to the rotation direction of the motor, ensuring it aligns with the direction indicated by the arrow.
The operation procedures for a horizontal multistage centrifugal pump include startup, operation, and shutdown. Below are precautions for each phase:
Startup Precautions:
1. Before starting the multistage centrifugal pump, manually rotate the rotor to ensure smooth movement without any obstruction.
2. Check if the rotation direction of the motor matches that of the pump.
3. Verify the tightness of the connection bolts between the multistage pump and the motor, ensuring the safety of the surroundings, and prepare for pump startup.
Operating Precautions:
1. Regularly check for leaks in the packing seal or mechanical seal. If using a packing seal, consider using oil-immersed graphite packing. For high-pressure pumping, reinforced packing may be necessary. Monitor the temperature of the sealing surface and check the oil level and condition of the oil ring. Multistage centrifugal pumps can have either roller bearings or sliding bearings, which require lubrication with either oil or grease. Operators should monitor bearing temperatures to ensure normal operation.
2. Multistage centrifugal pumps may experience axial movement during operation. Maintain proper clearance between the motor and pump coupling faces. Regularly check the coupling opening distance and assess the wear of the balance disc. Monitor the tightness of anchor bolts, and observe consistency between the temperature of the pump body and the suction port. Check for fluctuations and vibrations in the outlet pressure gauge.
Shutdown Precautions:
Before shutting down the multistage centrifugal pump, close the pressure gauge valve gradually, then gradually close the outlet gate valve. Only stop the motor rotation after the outlet gate valve is fully closed.
These precautions ensure the safe and efficient operation of light horizontal multistage centrifugal pumps.
