The function of the pressure-stabilizing pump is to stabilize the most unfavorable water pressure in the fire water supply system. For high-rise or multi-storey buildings using temporary high-pressure fire-fighting water supply systems, when the height of the fire-fighting water tank cannot meet the water pressure requirements of the system's most unfavorable point fire-extinguishing equipment, a pressure-stabilizing pump should be installed.
I. Setting requirements
1. Flow requirements
1) The planned flow of the pressure-stabilizing pump should not be less than the normal leakage of the fire water supply system pipe network and the system's initiative to start the flow.
2) The normal leakage of the fire water supply system pipe network should be confirmed according to the pipeline materials, interface methods, etc. When there is no leakage data of the pipe network, the planned flow rate of the stabilized pump should be calculated as 1% ~ 3% of the planned fire water supply flow rate. It should not be less than 1L / s.
3) The active starting flow rate of the alarm valve pressure switch used in the fire water supply system should be confirmed according to the product.
2. Pressure requirements
1) The planned pressure of the pressure-stabilizing pump should meet the requirements of the system's active start and flooding of the pipe network.
2) The planned pressure of the pressure-stabilizing pump should adhere to that the pressure at the system active starting pump pressure setting point is greater than the system setting active starting pump pressure value in the quasi-operation state, and the added value should be 0.07 ～ 0.10MPa.
3) The planned pressure of the pressure-stabilizing pump should adhere to the hydrostatic pressure of the water fire extinguishing facility at the most obscure gas point of the system in the quasi-operating state should be greater than 0.15MPa.
3. Generally, the pump with low flow rate and high head is used for the pressure-stabilizing pump, and a spare pump should be set up, generally based on the principle of "use one for one".
4. The self-priming water absorption method should be used for the regulator pump. When selecting a natural water source, take measures to avoid clogging of debris at the suction port of the pump.
5. The centrifugal pump should be used for the pressure-stabilizing pump, and the single-suction single-stage or single-suction multi-stage centrifugal pump should be used; the raw materials of the pump casing and impeller should be stainless steel.
6. The temporary high-pressure fire-fighting water supply system where the pressure-stabilizing pump is installed shall be provided with technical measures to avoid frequent starting and stopping of the pressure-stabilizing pump. When a pneumatic water tank is selected, its conditioning volume shall be calculated based on the number of times that the pressure-stabilizing pump is started and not more than 15 times / h Confirmed, but the effective storage volume should not be less than 150L.