Until now, X70 has been the most common steel grade used for onshore long-distance pipelines. Use of X100 will enable wall thickness of the pipe to be reduced for transmission of natural gas at higher pressures, leading to significant cost savings, improved pipeline construction costs and overall operational efficiency, fuelling expectations at NKK of widespread application for the new product.
Since beginning development of the X100 pipe manufacturing technology in 1987, NKK has developed a number of important technologies, among which are:
Steel plate production technology based on the Super-OLAC (on-line accelerated cooling)
process, which allows rapid, uniform, cooling throughout the plate immediately after hot
rolling. The resulting plate gives X100 linepipe superior strength without deteriorating toughness, and improved weldability.
Highly-accurate UOE pipe forming and high-quality seam-welding technologies, effectively controlling the spring-back and peaking peculiar to higher-strength steels.
These, and other issues concerning X100 and X120 pipe, will be discussed at a major conference being held in Yokohama on 7-8 Novenber. The Pipe Dreamer conference, organized by Professors Masao Toyoda of Osaka University, and Rudi Denys of the University of Gent, will explore a wide range of issues concerning this critically-important development for pipelines in hazardous and environmentally-challenging areas.