The water tank overflow tube can be from the side wall or the bottom, its diameter blood according to the discharge tank maximum into the flow determined, and should be better than the intake of the main L 12th. No valves shall be installed on overflow tubes. Overflow pipe must not be directly connected with the drainage system, the use of indirect drainage, overflow tubes should be in the dust, insects, flies and other measures, such as water seal, filter nets, and so on.
Drain pipes of water tanks shall be picked up at the lowest bottom. Water drain diagram 2-2n fire and life table water tanks fitted with gate valves (should not mount the valve), can be connected with the overflow pipe, but not directly with the drainage system. The pipe diameter is generally adopted by DN50 without special requirements.
The water tanks for potable water shall be provided with a sealed lid and a manhole cover and a vent pipe shall be provided. Ventilation tubes can be stretched indoors or outdoors, but not to reach harmful gases, the pipe should be prevented from dust, insects and mosquitoes into the filter, generally should be set down the mouth. The ventilation tube shall not be fitted with valves, water seals and other obstructing devices. Ventilation tubes shall not be connected with drainage systems and ventilation lanes. Ventilation tubes generally adopt DN50 diameter.