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What are the installation requirements of diesel engine self

Article provenance:Hai Rui ZhonglianPopularity:Publication time:2020-03-25 10:34

What are the installation requirements of diesel engine self-priming pump

Installation of diesel engine fire pump

1. When driving diesel engine fire pump, pay attention to the coaxiality of pump shaft and motor output. The installation accuracy of diesel engine fire pump has a great influence on the stability and service life of the pump, so it must be carefully installed and corrected.

2. The coupling of diesel engine fire pump must be firm with nuts, and the nuts must be locked. Be careful that the nuts are loose, otherwise it is easy to cause impeller movement and mechanical failure.

3. In order to maintain a certain amount of liquid storage in the diesel engine fire pump, to achieve better self-priming capacity and prevent dry friction of mechanical seal, the inlet of the diesel engine fire pump must be higher than the center line of the pump shaft.

4. Pay attention to the installation of diesel engine fire pump suction pipe

Self priming pump

1. The installation height of suction port shall not exceed 5m. If conditions permit, the installation height of the suction inlet shall be lower than the minimum storage level of the pool as far as possible, and the length of the suction pipe shall be shortened as far as possible, and fewer elbows shall be installed, which is conducive to shortening the self-priming time and improving the self-priming function.

2. The valve and flange in the suction pipeline shall be strictly protected to prevent liquid leakage or leakage, that is, no leakage is allowed in the suction pipeline.

3. Prevent solid and other impurities from inhaling into the pump body. Therefore, a filter should be installed in the suction line. The effective water passing area of the filter shall be 2-3 times of the suction pipe section, and the filter shall be checked regularly.

4. The suction pipe and nozzle shall have their own support, and the pump body itself is not allowed to bear the load of the pipe.

5. When installing the pump, the static grounding resistance of the pump and pipeline shall meet the specified requirements.

6. Strictly check whether there are stones, iron sand and other sundries in the pump casing and pipeline.

7. Correct the installation clearance and coaxiality of pump coupling and motor coupling. The tolerance of different axiality is 0.1mm. The height difference between the pump shaft and the motor shaft can be adjusted by copper or iron on the feet.

8. The final inspection shall be conducted after the actual operation of the unit for 3-4 hours. If there are no defects, the installation shall be completed and the shaft shall be checked during commissioning.

9. The pump bearing body is equipped with cooling water connector of cooling chamber device, which is used for the inner hole of 12 rubber pipes or plastic pipes, with the size of thread m12x1.75.

10. If a one-way valve is installed on the outlet pipeline of the pump, and the pump cannot discharge gas smoothly during self-priming, the exhaust pipe and valve shall be connected at the outlet of the pump.

Preparation and inspection before start

1. The series of self-priming pumps are lubricated with high-quality calcium base grease and No. 10 oil according to the working state of the pump. If the pump is lubricated with grease, the grease should be added to the bearing housing regularly and the pump should be lubricated with oil. If the oil level is insufficient, add.

2. Check whether the liquid storage in the pump housing is higher than the upper edge of the impeller. If the storage capacity is insufficient, fill the pump body directly from the filling port on the pump housing. In case of insufficient liquid storage, the operation shall not be started. Otherwise, it can not work normally, and it is easy to damage the mechanical seal.

3. Check whether the rotating part of diesel engine fire pump is stuck.

4. Check whether the nuts at the bottom foot of diesel fire pump body and each connection are loose.

5. Check the coaxiality and operation of the pump shaft and the electric spindle of the diesel engine fire pump.

6. Check whether there is leakage in the water inlet pipe. If there is leakage, try to eliminate it.

7. Open the valve of suction pipe and slightly (not fully) open the outlet control valve.

Starting and operation

1. Start the self-priming pump, and pay attention to whether the rotation direction of the pump shaft is correct.

2. Pay attention to whether there is abnormal sound and vibration during rotation.

3. Pay attention to the readings of pressure gauge and vacuum gauge. When the readings of pressure gauge and vacuum gauge keep stable after a period of fluctuation, it means that the pump is full of liquid and enters into normal infusion operation.

4. During the self-priming process before the pump enters the normal infusion operation, special attention shall be paid to the rise of water temperature in the pump. If the process is too long and the water temperature in the pump is too high, stop the pump and check the cause.

5. If the temperature of the liquid in the pump is too high and it is difficult to self-priming, the pump can be temporarily stopped, and the liquid in the discharge pipeline can be used to flow back to the pump or a liquid storage port is added on the pump body to directly supplement the liquid in the pump, so that the liquid in the pump can be started after cooling.

6. If there is strong vibration and noise during the operation of the pump, it may be caused by the cavitation of the pump. There are two reasons for cavitation: one is that the inlet velocity is too high, the other is that the suction distance is too high. When the flow is too large, the outlet control valve can be adjusted to increase the reading of the pressure gauge. When the inlet pipe is blocked, it shall be removed in time. When the suction is too high, the installation height of the pump can be properly reduced.

7. When the diesel engine fire pump is out of service for some reason in the process of operation, when the pump needs to be restarted, the outlet regulating valve shall be slightly opened (not completely closed), which is not only conducive to the discharge of outlet gas in the process of self-priming, but also can ensure that the pump is started under light load.

Pay attention to the leakage inspection of the piping system.

Pump stop

1. First, the gate valve on the discharge line must be closed.

2. Stop the diesel engine fire pump.

3. In cold season, drain the water in the storage tank in the diesel engine fire pump body and the cooling chamber in the bearing body to prevent the machine parts from freezing and cracking.