Know The Three Types Of Pipelines-Functional Use, Pressure Level And Material Type – PandaPipe

Know The Three Types Of Pipelines-Classification By Material

Pipes can also be divided into three categories according to material classification: metal pipes, plastic pipes and composite pipes.

Know The Three Types Of Pipelines-Metal pipes

Metal pipes are the oldest and most widely used of the three types of pipes.

• Common metal materials: carbon steel, stainless steel, copper, etc.
• Core features: high strength, high pressure resistance, and high temperature resistance.
• Common processes: seamless steel pipes and welded steel pipes.
• Application scenarios: Metal pipes are the most widely used material, mainly used in industrial production lines, energy transportation, and construction projects.

Plastic pipes

Although plastic pipes are the latest to appear, they are indeed the fastest growing.

• Main materials: PVC (polyvinyl chloride), PE (polyethylene), PPR (random copolymer polypropylene) and other polymers.
• Core advantages: light weight, easy transportation, convenient installation, corrosion resistance.
• Application scenarios: mainly used in civil buildings (toilet drainage, residential drainage), agricultural irrigation and chemical industry (corrosive liquid transportation).

Composite pipe

The new type of pipe composed of metal matrix and polymer material/reinforced fiber is called composite pipe. Its market share in the field of high-pressure transportation has reached 28%, and it is growing steadily at an annual rate of 9.7%.

• Core advantages: high strength and pressure resistance, best corrosion resistance, oxygen barrier and anti-permeability
• Common types: aluminum-plastic composite pipe, steel-plastic composite pipe, plastic-coated composite pipe, fiber-reinforced pipe
• Application scenarios: municipal livelihood field (water supply system, gas transportation), energy industry scenario (oil and gas gathering and transportation, hydrogen transportation), high-end industry and environmental protection.

Know The Three Types Of Pipelines-Classification by pressure level

According to the pressure level and temperature, it is divided into two categories: GD1 and GD2 pipelines.

Know The Three Types Of Pipelines-GD1

• Conditions: Design pressure ≥6.3 MPa or temperature ≥400℃
• Core scenarios: Main steam pipelines of thermal power plants (such as supercritical units), high-temperature reheat steam pipelines.
• ‌Material requirements: 15CrMoG alloy steel, INCONEL 625
• Safety control: 100% radiographic detection + high-temperature creep monitoring
• Typical wall thickness: ≥25 mm (DN300 pipeline example)

GD2

• Conditions: Design pressure <6.3 MPa and temperature <400℃
• Core scenarios: Medium and low pressure steam transmission pipelines (such as heating systems), steam turbine extraction pipelines
• ‌Material requirements: 20# steel, Q235B carbon steel
• Safety control: weld sampling rate ≥20%
• Typical wall thickness: 8~15 mm (DN300 pipeline example)

Know The Three Types Of Pipelines-Classification by purpose

According to their uses, they can be divided into two categories: process pipelines and power pipelines.

Process pipeline (material pipeline)

Function: Directly participate in the production process, transport materials
Design standard: ASME B31.3 “Process Piping” specification
Transport medium characteristics: Toxic/flammable/corrosive and other dangerous goods, high temperature and high pressure of P≥10MPa or T≥400℃

‌Power pipeline (media pipeline)

Function: Provide power support for equipment and transport auxiliary media.
Design standard: ASME B31.1 “Power Pipeline” specification
Transport medium characteristics: Steam/hot water/compressed air conventional media, P < 10MPa, T < 400℃ temperature and pressure conditions are relatively mild