Classification of gas pipelines in long distance and urban

1.4. Reasons for gas pipeline classification based on pressure: Gas leakage may lead to accidents such as fire, explosion, poisoning, etc. Compared with other pipelines, gas pipelines have higher airtightness requirements. The gas pressure inside the pipeline is different, and the requirements for pipeline material, installation quality, inspection standards, etc. are different. Generally speaking, the higher the pressure inside the pipeline, the greater the possibility of pipeline leakage, and the higher the quality requirements for the pipeline; But using pipelines with higher pressure can reduce the investment of the entire pipeline network.

Urban gas pipeline network system

2.1 Composition of Urban Gas Transmission and Distribution System

Gas pipeline networks and ancillary facilities with different pressure levels such as low pressure, medium pressure, and high pressure

Gas pressure regulating stations, pressure regulating boxes, and other pressure regulating facilities

Gas storage facilities

Monitoring and Scheduling Center

City Gate Station

2.2 Classification of urban gas pipeline network systems

According to the pressure mechanism of the pipeline network, it can be divided into:

First level system: A pipeline with only one pressure level, including medium pressure first level system and low pressure first level system

Secondary system: Gas pipeline with two pressure levels

Triple level system: Gas pipeline with three pressure levels

Multi level system: Gas pipelines with three or more pressure levels

2.3. When selecting a gas pipeline network system, the following factors should be considered:

Gas source situation: gas type, gas supply pressure, etc

Urban nature, scale, and geographical conditions

Existing urban gas facilities

User types and distribution

Situation of gas storage facilities

Gas pipelines crossing obstacles such as railways and rivers

（1） Gas pipelines crossing railways, highways, and urban main roads

Additional casing or trench needs to be installed and approved by relevant departments

Vertical crossing and pipe jacking construction are recommended.

（2） Gas pipelines passing through rivers

Crossing the riverbed: direct excavation, commonly used in the north; Top pipe construction

Laid along with the bridge

Install a pipe bridge

HDD Heat Shrink Wrap Sleeves is popular be used for crossing pipe project.

Heat Shrinkable Sleeves such as 3LPE Heat Shrink Sleeves，2PE Heat Shrink，Cold-Applied Polymeric Tape ,which is also popular be used for gas pipeline coating.