Installation, use, debugging, and common problem handling of multi-stage pumps

Installation plan for multi-stage pumps:

1. Before installation, carefully check the flow channel for any hard or foreign objects to avoid damage to the impeller and pump body during operation;

2. Carefully inspect the water pump unit to ensure that there is no damage during transportation and ensure that all components of the unit are intact;

3. During installation, the weight of the pipeline is not allowed to be added to the pump to avoid deformation and affecting normal operation; (If conditions permit, isolation measures should generally be taken for the water pump unit to minimize the vibration of the unit and pipeline system and the possibility of low-frequency resonance.)

4. Tighten the anchor bolts to prevent vibration from affecting the performance of the water pump unit or causing damage during startup;

5. Install regulating valves on the near and outlet pipelines of the pump, and a pressure gauge near the pump outlet. The pressure gauge should be installed in the middle of the straight pipe section far from the valve to ensure the accuracy of the gauge value, to control the operation of the pump in the rated or user required industrial and mining areas, and to ensure the normal use of the pump;

6. If there is a suction head at the working position of the water pump unit, a bottom valve should be installed at the suction inlet of the suction pipeline;

7. If a check valve is installed in the discharge pipeline, it should be installed outside the gate valve;

8. The installation methods of pumps are divided into rigid connection installation and flexible connection installation. (depending on the situation)

Debugging of multi-stage pumps:

After the installation of the water pump unit and accessories, a single machine test is required. The water pump operates for 2 hours on a single machine, and if conditions permit, a load test is carried out.

The single machine test of the water pump shall be carried out according to the following methods and steps:

1. Check whether the distribution cabinet meets the requirements and whether the motor wiring terminals meet the product requirements.

2. Remove the key from the motor and water pump coupling to separate the motor from the water pump.

3. Perform a spot test on the motor to check if the steering and sound are normal.

4. Connect the motor and water pump with a key, manually turn the gear, and check if there is any noise when the water pump rotates.

5. Conduct spot testing of the water pump unit. It is not easy to start the water pump for a long time without water, in order to avoid damaging the bearings of the water pump.

6. Close the outlet valve of the water pump, open the inlet valve, and exhaust the air inside the pump. Start the water pump unit, observe the pressure gauge value on the pipeline, and adjust the gate valve of the test pipeline to control the pipeline pressure, so that the pipeline pressure reaches the normal working pressure value of the water pump.

7. Observe the starting pressure value of the safety valve and adjust it so that the starting pressure value of the safety valve is 1.1 times the working pressure value of the water pump.

8. Check whether there is any leakage in the valves, fittings, and welding junctions.

The multi-stage pump should meet the following requirements during trial operation:

1. Each fixed connection part should not be loose.

2. The rotor and all moving components operate normally without any abnormal noise or friction.

3. The operation of the auxiliary system should be normal; The pipeline connection should be firm and leak free.

4. The temperature of sliding bearings should not exceed 70 ℃; The temperature of rolling bearings should not exceed 80 ℃; The temperature of special bearings should comply with the provisions of the equipment technical documents.

5. The safety protection and electrical control device of the pump, as well as various instruments, should be sensitive, correct, and reliable.