Assembly of DG type electric feed water pump
The assembly quality of the electric feed water pump directly affects the normal operation of the pump, and affects the service life and performance parameters of the pump; the vibration and noise of the unit are affected, and the following points should be paid attention to during assembly:
a. The concentricity of the combined parts of the fixed part is guaranteed by the manufacturing accuracy and assembly quality of the parts. The machining accuracy and surface roughness of the parts should be guaranteed, and no bumps or scratches are allowed. Molybdenum disulfide used as a sealant should be clean. The screws and bolts used for fastening should be evenly stressed.
b. The alignment between the outlet channel of the impeller and the inlet channel of the guide vane is ensured by the axial dimensions of each part. The quality of the flow channel to the neutral directly affects the performance of the pump, so the size of the pump cannot be adjusted at will.
c. After the pump is assembled and before the packing is installed, turn the pump rotor by hand to check whether the pump rotor rotates flexibly in the housing and whether the axial movement meets the specified requirements.
d. After the above inspection meets the requirements, add packing at the shaft seals at both ends of the pump. Pay attention to the relative position of the packing ring in the packing chamber.
Disassembly of DG type electric feed water pump
a. The disassembly should be carried out in the reverse order of the assembly, and the manufacturing accuracy of the parts should be strictly protected from damage during disassembly.
b. When disassembling the through rods, each middle section should be cushioned first to prevent the middle section from loosening and then sinking and bending the shaft.
Installation of DG type electric feed water pump
In addition to meeting the general technical requirements for installation, the following points should be noted when installing this type of pump:
1. When the motor and water pump are combined and installed, the shaft of the pump coupling end should be pulled out, and 3-5mm end face clearance value should be left to ensure the axial clearance value between the pump and the motor coupling.
Note: Make sure the bottom plate is leveled and the equipment level is good before grouting
Caution: In order for the installation to be successful, the coupling must be adjusted correctly. The flexible coupling cannot compensate for any obvious misalignment. Misalignment can cause rapid wear, noise, vibration, and damage to equipment. Therefore, the coupling must be adjusted within the given limits. Caution: Measures must be taken to support the inlet and outlet pipes of the pump to prevent excessive load on the inlet and outlet of the pump
2. The center lines of the pump and motor shafts should be on the same horizontal line.
3. The pump can only bear its own internal force, not any external force.
DG type electric feed water pump installation sequence
(1) When the unit is transported to the site, the motor has been installed for those with the base, and it is not necessary to remove the pump and motor when leveling the base.
(2) Put the base on the foundation, put a wedge-shaped horn near the anchor bolts, and pad the base by 20-40 mm, and prepare it for leveling and filling with grout.
(3) Use a spirit level to check the levelness of the base. After leveling, tighten the anchor nut and fill the base with cement slurry. After the cement dries, check the levelness again.
(4) When the power of the unit is high, the pump, motor and base may be packaged separately for the convenience of transportation. At this time, the user needs to install and calibrate the pump unit by itself. The method is as follows:
a. Wash the dirt on the support plane of the base, the feet of the water pump and the feet of the motor, and put the water pump and the motor on the base.
b. Adjust the level of the pump shaft, and tighten the nut properly after leveling to prevent it from moving.
c. Lift the motor, make the pump coupling and the motor coupling match, and lower the motor to the bottom to make the corresponding position;
d. Adjust the gap between the two couplings to about 5mm, and correct whether the axis of the motor shaft and the pump shaft coincide. The method is to put a flat ruler on the coupling, and the outer circle of the two couplings is level with the flat ruler. If they do not coincide, the relative position of the motor or pump should be adjusted, or the pad should be adjusted with a sheet;
e. In order to check the accuracy of the installation, the gap between the two coupling planes should be measured with a feeler gauge at several different positions on the circumference of the coupling, and the gap difference in one circle of the coupling plane must not exceed 0.3 mm. The difference between the top and bottom or left and right of the center line at both ends must not exceed 0.1 mm.
(5) When the unit does not have a base, it needs to be installed directly on the foundation. The method is similar to 4, but more attention should be paid to correction.
Precautions for installation of DG type electric feed water pump
1. The weight of the pipeline should not be borne on the pump during installation, otherwise the pump will be easily damaged;
2. The anchor bolts must be tightened during installation, and the pump should be checked every certain period of time to prevent it from loosening, so as to avoid severe vibration when the pump is started and affect the performance of the pump;
3. Before installing the pump, carefully check whether there are hard objects (such as rocks, iron sand, etc.) in the pump flow path that affect the operation of the pump to avoid damaging the flow components during the operation of the pump:
4. For easy maintenance and safe use, install a regulating valve on the inlet and outlet pipelines of the pump and a pressure gauge near the inlet and outlet of the pump. For high-lift pumps, to prevent water hammer, it should be installed before the outlet gate valve. A check valve to deal with accidents caused by power loss such as sudden power failure, so as to ensure that the pump runs under suitable working conditions and prolong the service life of the pump;
5. When the pump is used for suction lift occasions, it should be equipped with a bottom valve, and the inlet pipeline should not have too many bends, and there should be no water leakage or air leakage, so as not to affect the suction performance of the pump;
6. In order to prevent impurities from entering the pump and clogging the flow path to affect performance, a filter should be installed in front of the pump inlet;
7. Rotate the rotor parts of the water pump before installing the pipeline. There should be no friction or jamming. Otherwise, the pump should be disassembled to check the cause.
