NKK Corporation announced today that it has secured an order to supply its newly developed high-alloy laser-welded pipe to NAM, a Dutch joint venture between Shell and Exxon. NKK's original product has drawn high praise from Shell, which led to its application for the first time in the world as an anti-corrosion line pipe.

   The order represents approximately 1,100 metric tons of weldable martensitic stainless steel laser-welded pipe containing 13% chromium (product name: "NK-W13Cr"), which will be used in an onshore pipeline being built in the northern part of the Netherlands.

   Costly stainless steel pipes, such as duplex stainless and clad steel pipes, or carbon steel pipes with a special corrosion inhibitor, have been commonly used for line pipes in a CO2 corrosive environment. Recently, however, demand for less expensive stainless steel, such as weldable 13%-chromium steel, has increased due to the high cost of line pipe. Moreover, the use of inhibitors has become a matter of great concern since it entails the disposal of chemical material into the environment.

   The 13%-chromium steel features excellent corrosion resistance under a CO2 corrosive environment. While the steel has been widely supplied to a number of customers for OCTG (oil country tubular goods) applications, it had shortcomings relevant to weldability when used as line pipe: the steel required pre and/or post heat treatment after girth welding at the construction site.

   To overcome such problems, NKK successfully developed NK-W13Cr steel featuring improved weldability and good workability for both laser-welded pipe manufacturing and onsite construction, with excellent CO2 corrosion resistance.

   Moreover, until recently, customers were required to use thick-wall seamless pipes for certain onshore pipelines, even though they preferred thin-wall pipes. NKK is now able to satisfy the needs of its customers by providing thin-wall laser-welded pipes.

   NKK has been actively promoting its high-alloy pipes, including weldable 13%-chromium steel pipe, for seamless, UOE, and laser-welded pipe applications. The all-new laser-welded pipe will enable NKK to meet the versatile needs of its customers by providing a full range of dimensions, from small-to-large diameters and thin-to-thick walls.