Common materials of fire water system

1、 Type of fire water supply pipe

1. Ductile iron pipe: mainly used for buried pipeline in front of alarm valve of automatic sprinkler system and buried pipeline of fire hydrant system.

2. Welded steel pipe: mainly used for buried and overhead pipelines of fire hydrant system and buried and overhead pipelines in front of alarm valve of full-automatic sprinkler system and water spray system to transport low-pressure fluid. According to the wall thickness, it can also be divided into ordinary steel pipes and thickened steel pipes. According to the difference of processing technology, it can also be divided into ordinary welded steel pipe and hot-dip galvanized welded steel pipe.

3. Seamless steel pipe: it is mainly used for the main pipe or the pipe at the lower part of the system where the pressure is higher. According to the difference of processing technology, it can also be divided into hot rolling and cold rolling.

2、 Selection of fire water supply pipes

1. Outdoor fire hydrant water supply system

(1) When the outdoor fire protection is a domestic and fire protection pipe system or a low-pressure fire protection water supply system, ductile iron pipes, welded steel pipes, hot-dip galvanized welded steel pipes on the inner and outer walls, and PE water supply pipes of socket branch pipes with lower allowable pressure can be selected.

(2) When the outdoor fire water supply system is a temporary high-pressure or normal high-pressure water supply system, and the working pressure of the system is low, the pipes in the above (1) can be selected within the allowable pressure range of the pipes; When the working pressure of the system is very high, flange ductile iron pipe, welded steel pipe, internal and external hot-dip galvanized ordinary steel pipe or thickened steel pipe and seamless steel pipe shall be selected according to the specific conditions of the working pressure of the system.

2. Indoor hydrant water supply system

(1) When the working pressure of indoor fire hydrant system is ≤ 1.0Mpa, ordinary welded steel pipes and hot-dip galvanized ordinary welded steel pipes on inner and outer walls can be selected.

(2) When the working pressure of indoor fire hydrant system is 1.0~1.6Mpa, thickened welded steel pipe, hot-dip galvanized thickened welded steel pipe and seamless steel pipe can be selected.

3. Full automatic sprinkler system

The internal and external hot-dip galvanized steel pipes shall be selected for the water distribution pipeline. When the pipeline before the inlet of the alarm valve is made of non anti-corrosion steel pipes, a filter shall be designed at the end of the pipeline