Can the head of a centrifugal fan be changed?
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The pressure head of the boiler exhaust fan is 3500 Pa; in order to meet the requirements of the newly installed desulfurization tower, this pressure head needs to be increased to 5000 Pa, while the air volume remains unchanged. Questions: 1. Is it possible to modify the fan? 2. Should the size of the motor be changed, or the size of the blades? 3. Are the costs high?
I think to address this issue, one can first check the performance curve of that fan; generally speaking, as the head pressure increases, the flow rate definitely decreases. Moreover, the size of the fan blades is determined through balance calculations; making changes to it will accelerate the wear and damage of the fan. Changing the motor is relatively feasible.
In this case, it’s best to consult the fan manufacturer to find out which components of the old unit can still be used. However, personally, I think the value of those components that can still be utilized (such as the casing) is not high; the best option is to purchase a new one. :lol
I agree with choosing a new model. For the old fan, just replacing the motor means that various other components such as shafts and couplings also need to be replaced, which is costly. Why not spend the money on a device that meets our requirements?
It’s very simple – just cut the impeller a little smaller, but make sure it’s balanced
Modification is certainly possible. The impeller can be redesigned and the motor replaced. The air volume should remain the same, while the pressure needs to be increased by nearly 50% of the original value. The power of the motor definitely needs to be increased, so it will have to be replaced. The main shaft and bearings are likely to need to be replaced as well. Therefore, the cost might be similar to that of replacing everything with new parts
Check the performance curve of the fan to see if it falls within its operating range. If it is an inverter-driven motor, the speed of the motor can be increased automatically in order to raise the head pressure; however, if the motor power doubles, it is likely necessary to replace the motor. In typical designs, the motor is selected to have a capacity of 120%