Can a double-suction pump and motor be connected directly?
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As the title suggests, I’ve noticed that in our factory, everything is connected using couplings; wouldn’t it be more effective to connect the motors directly?
If the motor is connected directly, it’s very troublesome to assemble the pump.
If you have the means, go ahead and make one; don’t forget to share it here.
This post was last edited by 3983596_FPPZ on 2019-2-22 16:41. What does it mean to have a pump directly connected to a motor? Can I have a motor with a shaft that combines the pump shaft and the motor shaft into one? Could you be more specific? Why do we need to do this?
In the direct connection type, the motor shaft is a specially designed extended shaft that is connected directly to the pump; this results in a higher overall efficiency for both the pump and the motor.
1. The motor shaft is made of carbon steel, while the pump shaft’s material depends on the corrosiveness of the medium (unless the shaft does not come into contact with the medium); it is very likely that the materials of these two shafts will be different. 2. A shared shaft for the pump and the motor requires special customization. Unless the pipeline pump manufacturer can produce large quantities, which allows for lower prices, customizing such a shaft in small batches comes at a high cost. 3. The pump shaft is subject to frequent disassembly and assembly, as well as corrosion from the medium, making it a vulnerable component. If it needs to be replaced, the shared shaft must also be replaced, and the rotor of the motor mounted on that shaft has to be removed and reinstalled (via press fitting). This results in high maintenance costs and inconvenience, especially given the rising cost of labor. 4. Couplings generally have high transmission efficiencies, usually above 95%. Calculate whether the cost savings resulting from improved efficiency are greater than the costs associated with maintenance and repairs mentioned above. 5. If it is necessary to improve the efficiency of the coupling, a rigid coupling can be installed between the motor shaft and the pump shaft to address this issue.
In the case of a direct connection, if the pump shaft corrodes or gets damaged and needs to be welded, it is necessary to remove the motor rotor as well
Direct connection makes it difficult to maintain and repair the pump
Diaphragm couplings have a very high transmission efficiency, reaching 99.86%; you should consider ways to improve the efficiency of the pump as well as that of the motor