Change pump flow rate
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【When the discharge flow rate of the fire pump is 150% of the flow rate at the selected operating point, its head shall be not less than 65% of the head at that selected operating point; when the pump is turned off, its head shall not exceed 140% of the head at the selected operating point.】 】 I would like to ask: Can the flow rate be increased from the rated value to 1.5 or 1.5 times the rated value on one’s own, or is it necessary to have someone modify the pump? The shaft power is 665 kW at the rated flow rate, and it rises to 749 kW at 1.5 times the rated flow rate; a 800 kW motor isn’t sufficient, right?
I don’t understand this question; what exactly are your requirements and goals? With such a large deviation, it’s unlikely that the pump manufacturer can achieve it
Pump manufacturers should be able to do this; it is a mandatory requirement for fire pumps. I don’t know much about how pumps work; it seems that to increase the flow rate of a pump, the impeller would need to be changed.
It is recommended to use an inverter-driven motor; that will solve everything
This post was last edited by henglinkou on 2021-1-13 at 11:16. During actual operation, the actual flow rate of the pump is related to the total resistance loss downstream of the pump; if the total resistance loss is less than the inlet pressure of the pump plus its rated head, then the actual flow rate will be greater than the rated flow rate, and the actual head will be less than the rated head. The same principle applies in reverse. This is the pump’s own performance
This is a fire pump; unlike ordinary pumps, the motor power must be chosen to cover the entire performance curve
It is a characteristic of the fire pump itself, and there is no need to manually adjust the pump outlet valve to make changes. 800KW is enough.
Provide the parameters to the manufacturer for selection
An 800kw motor will be sufficient; using an inverter-driven motor is perfectly fine
It’s the parameters provided by the manufacturer, and we think they’re unreasonable
If 800 kW is sufficient, the motor efficiency needs to be very high; a safety factor of 1.05~1.08 also needs to be taken into account for the motor