Method for the manufacture of tubes from steel having high ductility at low temperature

摘要

Tubes and method of manufacturing tubes from alloyed steel adapted to be welded for underwater hydrocarbon pipelines having high ductility at low temperatures. A low carbon alloyed steel containing less than 0.08% carbon and with at the most 0.30% silicon, also containing manganese and a metal generating special carbides such as molybdenum, niobium, vanadium and like-acting substances, is cast in a centrifugal casting mould after which the centrifugally cast tube is subjected to controlled cooling and a thermal treatment. Tubes so constructed may be used for drilling tubes, tubes for underwater pipelines and tubes for the construction of drilling platforms at sea in cold regions and applications requiring high ductility at low temperature.