The L415Q seamless steel pipes developed by Bao Gang United Steel Group's pipe company. [Photo/Inner Mongolia Daily]

Bao Gang United Steel Group's pipe company in North China's Inner Mongolia autonomous region has supplied its independently developed L415Q seamless steel pipes for a carbon capture, utilization, and storage (CCUS) demonstration project in Xinjiang Uygur autonomous region. The delivery marks a breakthrough in the application of high-grade pipes for carbon dioxide transportation in China.

The pipes are currently the highest-grade seamless steel pipes used in China's supercritical CO₂ transportation projects.

Supercritical CO₂ pipelines face extreme operating conditions. During pressure release, rapid CO₂ expansion can cause local temperatures to drop below −60 C, posing a risk of brittle fracture. This requires pipes to have exceptional strength, low-temperature toughness, and weldability.

To meet these requirements, the company optimized its production processes, from rare-earth microalloying and precision rolling to heat treatment. The delivered pipes met all mechanical performance standards and earned positive feedback from the construction team on their weldability.

The company also provides on-site technical support during storage, welding, and installation, using project feedback to improve its products and manufacturing processes.