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Automatic welding of a 30" diameter, 33 mm wall thickness pipeline onshore the Shetland Islands UK, has been carried out recently by the contractor SICIM for the TOTAL Laggan-Tormore project. The base material was L450MB grade pipe steel. Such a heavy wall thickness is unusual for onshore pipe lines. The mechanical property requirements include the cri-teria that the strength of the weld metal must over-match the base material and to generate high toughness weld metal at low temperatures. Additional toughness requirements derived from an Engineering Critical Assessment (ECA), implemen-ted by SICIM to ensure that a post weld heat treatment was not required. SICIM has qualified a downhill mechanised orbital welding procedure with a narrow-gap bevel using an automatic welding system of its own design and manufacture using a low cdloyed l%Ni MAG welding consumable. This MAG welding wire was developed recently by Air Li-quide Welding and has been specifically designed for these demanding pipeline welding applications. Mechanical pro-perties achieved in the weld procedure qualification testing programme were excellent, with high levels of toughness in both the weld metal and HAZ at a high level of weld metal strength. Due to the performance of the automatic welding system and the expertise of the contractor, combined with a specifically designed procedure and welding consumable, this pipeline has been completed with high quality and at a high level of productivity. [ABSTRACT FROM AUTHOR]