First Application of China’s Self-Developed CMT Fully Automatic Welding Equipment Builds “Long-Life” Subsea Pipelines

On August 14, Offshore Oil Engineering announced that China’s independently developed offshore engineering CMT (Cold Metal Transfer) fully automatic welding equipment had been put into use for the first time in the Qatar ISND5-2 project. This helps enhance the intelligence level of offshore engineering equipment and accelerates offshore oil and gas development.

This time, the equipment was used for welding 13 kilometers of strongly acidic, sulfur‑corrosion‑resistant subsea pipelines, with the main construction vessel being “Offshore Oil 201.” The equipment has accumulated more than 1,200 hours of operation, completed over 1,000 weld joints (with a total weld length of about 1,000 meters), and achieved a one‑time pass rate of over 97%. Key indicators have met the targets, verifying its reliability under complex working conditions. Leveraging CMT technology, the equipment achieves low heat input and spatter‑free welding, reducing weld defects. It also uses AI algorithms to optimize parameters for precise control of temperature and deposition; the team has additionally developed a self‑designed backing‑free welding process to improve weld corrosion resistance.

Previously, R&D of this type of equipment in China faced technical bottlenecks. Offshore Oil Engineering, together with universities and manufacturers, overcame more than 20 technical challenges and optimized the system through hundreds of tests. The team is currently building an equipment management system to promote large‑scale application.