【 Weak current College 】 community water supply and sewerage and water heating, water supply-section II-Community water system

This section on the selection of community water supply, a different type of community water supply system of water-supply design, the community of a simple calculation, water supply pipe layout and laying, community water supply design flow to determine principles and booster stations, and other content for more system. 　　In the learning section, it should be noted that the distinction between different water ways and characteristics, different types of community water system determines the basis and method, water supply pipe alignment principles and layout requirements should consider laying, design for community water supply and water use of calculation, community water supply design flow to determine the principles and content of the booster station requires only for general understanding. First, choose the style and the community water supply and water supply in the community there are urban water supply direct water ways and community focus or diversify feedwater way two types. 1. urban water supply direct water way
Direct water in two situations: ① water pressure to meet the requirements, use feedwater supply directly; ② pressure does not meet the requirements, by setting the roof storage water supply.

2. Community centralized or decentralized way pressurized water
Urban supply pressure does not meet the requirements of community water supply pressure, you should use feedwater community. Community feedwater method is divided into set compression mode and distributed compression. Life, the production of common water there are several ways.
① pool-water pump.
② pool-water pump-water tower.
③ pool-water pump-water tanks.
④ pipeline pump directly pumped water tanks.
⑤ pool-water pump-pressure tank.
⑥ pool — variable speed pump.
⑦ pool — variable speed pump and pressure tank mix.
Different water ways have different advantages and disadvantages.

3. community water supply mode selection method
① According to city (town) water supply conditions, community size and water requirements, technical and economical comparison, social and environmental benefits, and so on comprehensive evaluation.
② the way to the water supply in the community, make a selection, you should make full use of the cities (town), water supply network pressure, direct water takes precedence. 　　Use feedwater manner, on the water supply network pressure meets the floor General or direct water supply. Second, different types of community water supply system of the community water supply system and city (town), and adapted to the water supply system, water supply systems is generally divided into life and fire water system. ① low layer and multilayer construction of residential, General not set indoor fire water system, the use of life and fire water supply system. 　　② multilayer, high-mix of residential district water supply system should be adopted, with some tall buildings shall be based on the number of high-rise construction, distribution, height, properties, management, and security, through technical and economical comparison, determine the dispersion, partitioning set or centralized storage pressure water supply system. Several concepts: ① dispersed storage Booster system: refers to the number of high-rise buildings have only one building or building number, but the building supply pressure requires larger differences, each building separate set pool and water pump of pressurized water supply system. ② piecewise centralized storage Booster system: refers to the community some similar high-rise buildings fragment with a water tank and pump pressure water supply system. 　　③ centralized storage Booster system: refers to the community of all high-rise building with a water tank and pump pressure water supply system.　　Partitioning set and centralized storage booster water pressure system, a total investment of a province, ease of administration, but in the earthquake area less secure. Third, community water supply design calculation of water use feedwater design water consumption in the living area includes residential water consumption, water consumption, public buildings, fire-fighting water poured roads and green water, the water pipe leakage and the water is not foreseen. Its water quota and coefficient of variation of hours under the property equipment facilities management (Liu, Wang Wei yan editor-in-Chief, telecommunications press) Schedule 2; public building of domestic water consumption coefficient of variation of fixed and hours as the building code for water supply and sewerage; residential outdoor fire water consumption according to the different building types and uses of the property, equipment and facilities management, schedule 6, 7; residential community poured road, green water and pouring times provided in the following table. The project water consumption/
Pouring times/
Pouring road and venues
Green water 1.0 ~ 1.5
1.5 ~ 2.02 ~ 3
L-2 (4) water supply piping layout and installation of water supply pipeline includes the entire community of water supply pipes as well as the community of pipes and households. Alignment principles: first by arrangement drinking water community road network, and then dry living group layout community branch pipe and households. Community water supply main pipe layout can refer to urban water supply requirements and forms.　　Layout of the pipeline network to spread throughout the entire community to ensure that each living group has the appropriate water points. In order to guarantee the water supply, water supply piping layout and installation should meet the following requirements. ① the community dry pipe should be arranged circular or and municipal water supply pipe in a ring network. ② Community branch pipe and tube received household, usually branched. ③ Community branch pipes should be of total length. ④ high-rise buildings and water demands high, the use of ring-shaped layout, from different sides of two community sewer pipe connecting community and household pipe to ensure water supply security and meet the fire requirements. ⑤ water supply pipeline and other pipe parallel or cross-laying of the net margin, according to the pipeline type, depth, construction and maintenance of interaction, pipeline subsidiary structure size and local codes, and other conditions. ⑥ living water pipeline and sewerage pipeline cross, water supply pipe should be laying in the sewers, and should not have the interface overlap; when water supply pipeline laying in the sewers below, water supply pipe interface from sewer pipe level spacing should not be less than 1m. ⑦ frozen in northern regions need to consider the impact of frozen soil, the community water supply pipe diameter not greater than the tube bottom 300mm buried deep below the frost line (d + 200mm). 　　⑧ water pipes and household pipe layout, you should be aware of and other pipeline comprehensive coordination problems. 5. community water supply design flow determination principle ① received household and community branch, design flow according to the burden ofTotal health apparatus. 　　② community living water supply main pipe, design flow according to the maximum hourly flow-rate calculation. 6. Community booster station 1. community water supply pressure station
Pressure station by pumping stations, reservoirs, water towers and auxiliary structures, etc. According to the function can be divided into booster station and water storage compression station. Booster station press pressure technology can be divided into a tower of pressurization station, pressure booster station and variable speed booster station. The latter two compression station can not set a water tower.

2. pump room type, composition and water pump selection
(1) pump room types and composition
Pump types have a circle, rectangle, surface, semi-underground, underground, since irrigation and non-self-and other types of irrigation. General community select semi-underground, rectangles, and since irrigation-pumping station.
The composition of the pump house in the community including pump, power equipment, water and pressure pipe and ancillary equipment.
(2) pump selection
Community selection horizontal centrifugal pump water pump more, lift high the optional multi-stage centrifugal pumps. Pump house isolated noise requirements high, vertical centrifugal pump can also be selected.
There are also responsible for pressurization station fire water pump flow when the task should take into account the living water flows and fire water flow. Select pump, pump lift should generally be and the same compression station design lift.

3. water tank
Set the pool is designed for storage tank volume, to guarantee the time of consumption, the effective volume of the tank under community living water storage capacity of storage, security, and fire water storage capacity.