Cautions for Use of Centrifugal Pump in Kehai Mechanochemical Industry

The working principle of chemical centrifugal pump is that when the pump is filled with water, the impeller rotates to produce centrifugal force, and the water in the impeller channel is thrown outward under the action of centrifugal force to flow into the pump shell, so the centrifugal pressure of the impeller decreases, which is lower than the pressure in the intake pipe. Under the action of this pressure difference, water flows into the suction tank. Impeller. In this way, the pump can continuously absorb water and continuously supply water. In addition to the role of impeller, the role of spiral pump shell is also very important. The liquid obtained energy from the impeller has a greater function when it flows out of the impeller. These liquids are collected in the spiral pump shell and transformed kinetic energy into pressure energy in the back diffuser.

Compared with other kinds of pumps, chemical centrifugal pumps have many advantages, such as simple structure, not easy to wear, stable operation, low noise, uniform water, convenient adjustment and high efficiency, so chemical centrifugal pumps have been widely used.

Notes for the use of chemical centrifugal pumps:

Installation instructions for chemical centrifugal pumps

1. Pipeline weight should not be added to the pump during installation. Each supporting body should be provided to avoid deformation affecting operation performance and service life.

2. Pumps and motors are integral structures, which need not be aligned during installation, so they are very convenient to install. Kehai Machinery

3. The anchor bolt must be tightened during installation so as to avoid the influence of vibration on pump performance during starting.

4. Before installing the pump, carefully check whether there are hard substances (such as stones, iron particles) in the pump runner that affect the operation of the pump, so as to avoid damaging the impeller and pump body during the operation of the pump.

5. In order to maintain conveniently and use safely, a regulating valve is installed on the inlet and outlet pipelines of the pump and a pressure gauge is installed near the outlet of the pump to ensure the normal operation of the pump and increase the service life of the pump.

6. Pump for suction range occasions, should be equipped with bottom valves, and the inlet pipeline should not have too many bends, at the same time, there should be no leakage, leakage phenomenon.

7. The discharge pipeline, such as the check valve, should be installed outside the gate valve.

8. When the pump shaft is moved after installation, the impeller should be frictional or stuck. Otherwise, the pump should be disassembled to check the cause.

9. Pump installation is divided into rigid connection and flexible connection.

Starting and stopping of chemical centrifugal pumps:

(1) Pre-start preparation

1. Hand-operated rotor blade, impeller should be free of grinding phenomenon, flexible rotation.

2. Open the inlet valve, open the exhaust valve to fill the whole pump chamber, and then close the exhaust valve.

3. Manual disc pump is used to make lubricant enter the mechanical seal face.

4. Point the motor to determine whether the steering is correct.

(2) Starting and operation

1. Open all the inlet valves and close the vomiting pipeline valves.

2. Turn on the power supply, when the pump reaches the normal speed, then gradually open the valve in the exhaust pipeline, and adjust to the required working conditions.

3. Pay attention to the reading of the instrument, check the leakage of the shaft seal, the leakage of the mechanical seal in normal time, <3 drops/minute, check the temperature rise of the motor and bearing <70 degrees C, if abnormal situation is found, it should be handled in time.

Parking

1. Close the vomiting valve gradually and cut off the power supply.

2. Close the inlet valve.

3. If the ambient temperature is below 0 C, the liquid in the pump should be exhausted to avoid freezing cracking.

4. If long-term shutdown, the pump should be disassembled, cleaned, packaged and kept.

3. Maintenance and maintenance of chemical centrifugal pumps:

(1) Maintenance and maintenance in operation

1. Water pipes must be highly sealed.

2. Prohibit long-term operation of pump under cavitation condition.

3. It is forbidden for the motor to run over current for a long time when the pump is running at the flow rate.

4. Check the running of the pump regularly, and the motor overcurrent runs for a long time.

5. Pumps should be supervised by special persons during operation to avoid accidents.

6. The pump should refuel the bearing every 500 hours. The motor power is greater than 11KW with refueling device, which can be directly injected with high-pressure oil gun to ensure good lubrication of bearings.

7. After long-term operation of the pump, when the noise and vibration of the unit increase due to mechanical wear, stop and check, and replace the fragile parts and bearings if necessary. The overhaul period of the unit is generally one year.

(2) Maintenance and maintenance of mechanical seals

1. Mechanical seal lubrication should be clean without solid particles.

2. It is strictly forbidden for mechanical seals to work under dry grinding conditions.

3. Before starting, the disc-driven pump (motor) should be several turns, so as to avoid the damage of sealing ring caused by sudden starting. Kehai Machinery