DN400 LSAW Pipes

LSAW: "Customized" Molding, Adapted to High Pressure but Slightly Inefficient

The core advantage of LSAW is customization, because the specifications of a single steel plate can be flexibly adjusted to meet the special needs of thick wall and high pressure, but it also leads to its relatively discrete production process. In the LSAW workshop in Huayang, to produce a X70 steel pipe with DN800 and a wall thickness of 20mm, it takes 12 processes from the steel plate entering the factory to the finished product leaving the factory, in which "U-O forming" only takes 30 minutes, plus welding, subsequent water pressure test and ultrasonic flaw detection, the production cycle of a single finished product is about 2 hours, and the daily production capacity of a production line is about 120 tons.

This "slow work and fine work" process makes the weld quality of LSAW pipe extremely stable. In a deep-sea project in Bohai Oilfield in 2023, the DN600 LSAW pipe provided by Huayang had to withstand a high pressure of 10MPa. By optimizing the welding parameters (current 600A, voltage 32V), the impact toughness of the weld reached 42J at -20℃, far exceeding the 30J required by the project, and finally passed the rigorous verification by a third-party testing organization.