Do You Know The Seven Selection Methods For Fire Pumps?

Aug 27, 2024

1. Choose high-efficiency, low-noise, and energy-saving centrifugal pumps. It is strictly prohibited to use obsolete products.
2. Select the pump based on the design flow rate and required head. Considering that the wear and tear of the fire pump leads to a decrease in pump output, the calculated head h can be multiplied by a coefficient of 1.05-1.10 to select the mud pump. The characteristic curve should be selected with a pump whose pressure head gradually decreases with increasing flow rate, so that the pump can run smoothly and reliably in parallel, and the working point of the pump can be maintained at a high level. Efficient intermittent operation, energy-saving, and less prone to damage to components.
When there are no regulating facilities in the water supply network, it is advisable to use speed regulating pump sets or rated speed regulating pump sets to operate the water supply in groups. The larger water output of the pump unit should not be less than the design flow rate of the regional water supply, and should be inspected under fire conditions.
4. When selecting lifting pumps for water tanks and towers, the number of pumps should be minimized as much as possible, and one unit should be configured as much as possible; When a pump can meet the requirements, multiple pumps should not be connected in parallel; If multiple parallel or large/small pump configurations are necessary, centrifugal pumps should be used. The model and quantity of pumps should not be too many, generally not exceeding two models, and the lifting range of single-stage clear water centrifugal pumps should be similar; During operation, each pump should still operate in the high-efficiency zone.
5. The design water supply flow rate of the variable frequency speed regulating pump should meet the requirements of the larger design secondary flow rate of the domestic water supply system. The power supply of the mud pump must be reliable, and the working point of the pump should be selected in the efficient working area of the pump characteristic curve, rather than the extension line of the Q-H curve. The unfavorable operating point should be located at the right end of the high-efficiency section of the pump characteristic curve, that is, the low point of the high-efficiency section of the pump characteristic curve and the pipeline characteristics, which can meet the requirements of high pump output and low head. Intersection of sexual curves. The speed regulation range of the pump should be within the high-efficiency range of the pump as much as possible, and the speed regulation range should be between 25% and 100% of the pump's water supply. The equipment should have automatic water level control function.
6. The multi-stage pump unit of the domestic pressurized water supply system should be equipped with a backup pump. The water supply capacity of the standby pump should be greater than that of the operating pump. The pump should automatically switch and operate alternately.
7. The voltage of the centrifugal pump should be the same, and the power supply method should be the same as that of the State Grid.