Selecting the Right Seamless Steel Pipes

When choosing seamless steel pipes, the GB/T8163 standard is typically suitable for applications where the design temperature is under 350°C and the pressure is below 10.0MPa, covering oil, oil-gas, and utility media.

For oil and oil-gas media exceeding 350°C or 10.0MPa, the GB9948 or GB6479 standards are recommended. Similarly, for pipelines in hydrogen environments or stress corrosion-prone conditions, GB9948 or GB6479 should be selected.

In cases where carbon steel pipes are used at temperatures lower than -20°C, the GB6479 standard is necessary as it defines requirements for low-temperature impact toughness.

The GB3087 and GB5310 standards are dedicated to boiler steel pipes. According to the "Boiler Safety Supervision Regulations," all pipes connected to boilers must comply with these standards. Thus, steam pipes in boilers, power plants, heating systems, and petrochemical production must use GB3087 or GB5310 standards.

High-quality steel pipes, such as those conforming to GB9948, are more expensive—approximately 20% more than GB8163 materials. Hence, selecting steel pipe standards requires balancing reliability and cost. Additionally, per GB/T20801 and TSG D0001, GB3087 and GB8163 pipes are not suitable for GC1 pipelines unless they pass ultrasonic testing and meet L2.5 grade or higher, for design pressures up to 4.0MPa.