No negative pressure water supply unit

No negative pressure water supply equipment

Non-negative pressure water supply equipment is a secondary pressurized water supply equipment that directly connects the pressurized water supply unit with the municipal water supply network and provides water supply in series on the basis of the residual pressure of the municipal water network to ensure that the pressure of the municipal pipe network is not less than the set protection pressure (the set pressure must be higher than the pressure demand of the direct supply area of the community, generally not less than 1.2Kg).

The core of pipe network superposition (no negative pressure) water supply equipment is how to prevent negative pressure during the operation of the secondary pressure water supply system, eliminate the impact of unit operation on the municipal pipe network, and achieve reliable, stable and continuous water supply without affecting the water consumption of nearby users.

Non-negative pressure water supply equipment is also known as pipe network superimposed pressure water supply equipment, at present, there are mainly tank type non-negative pressure water supply equipment and box type non-negative pressure water supply equipment.

Working principle

The stable flow tank type non-negative pressure water supply equipment is directly connected with the municipal pipe network, and the water supply is connected in series and superimposed on the basis of the residual pressure of the municipal pipe network.

(1) Variable frequency constant pressure water supply: when the water supply of the municipal pipe network is greater than the water consumption of the user, the stable flow tank without negative pressure water supply equipment is variable frequency constant pressure water supply, and a certain amount of pressurized water is stored in the stable flow tank.

(2) Eliminate negative pressure: When the increase in user water consumption causes the pressure to drop at the connection between the municipal pipe network and the steady flow tank, when the pressure is reduced to below the relative pressure 0, negative pressure is formed in the steady flow tank, the intake valve of the vacuum suppressor is opened, and the atmosphere enters the steady flow tank. At this time, the steady flow tank is equivalent to an open water tank with a free liquid surface, the pressure is the same as the atmosphere, and the negative pressure is eliminated. When the water level drops to the set value, the level controller transmits the control signal to the control system in the frequency conversion control cabinet, controls the pressurizing unit to stop working, and the user stops the water; When the user's water consumption is reduced, the water level in the steady flow tank rises, the gas is removed from the vacuum suppressor exhaust valve, and the pressure returns to normal, the pressurizing unit restarts automatically to restore the water supply.

(3) Water shutdown function: When the municipal pipe network stops water, the pressurizing unit automatically stops operation under the control of the liquid level controller, and the municipal pipe network water supply is restored, and the normal water supply is resumed automatically.

(4) Small flow hibernation function: when the user does not use water or the water consumption is very small, the device automatically enters the hibernation state (shutdown) and maintains the water supply pressure, and the system automatically wakes up when the user recovers water and restores the normal water supply.

(5) Power failure continues to supply water: when the community power failure, the municipal pipe network continues to supply water to users in low areas, power failure does not stop water. After the power supply is restored, the device automatically starts to restore normal water supply.

Installation instructions

1. the equipment should be installed on the basis of strength not less than C20 and surrounded by drainage facilities and maintenance channels;

2. the equipment installation location should be selected in a dry environment, avoid in the open environment, so as to avoid damage to electrical components;

3. before installation should carefully check the pump body abortion there is no hard objects, so as to avoid damage to the impeller and pump body during operation;

4. the pipeline is not allowed to be added to the pump during installation, so as not to deform the pump and affect normal operation;

5. according to the sequence of installation drawings, the connection is sealed, not forced installation, the main pipe should be supported when the diameter is large, so as to avoid stress;

6. tighten the anchor bolt, so as not to start the vibration on the pump performance;

7. Install regulating valves on the inlet and outlet pipes of the pump, and install pressure gauges near the pump outlet to control the operation of the pump in rated working conditions and ensure the normal use of the pump;

8. the pipeline system test pressure is 1.5 times the rated pressure, and continue to maintain more than 5 minutes. In the process of pressure test, the pipeline system must not have cracks, dripping, leakage, seepage phenomenon;

9. If the discharge pipe is installed with a check valve, it should be installed outside the gate valve;

10. the installation of the pump is divided into hard connection installation and flexible connection installation.